Inflammatory Back Pain Known or Suspected Axial Spondyloarthropathy PCAs. MRI can also detect chronic structural changes on axSpA in the sacroiliac joints and spine, although the clinical utility of follow-up for that purpose is not Inflammatory Back Pain established [110,137]. Noncontrast and contrast-enhanced MRI have overall similar diagnostic utility for evaluation of the sacroiliac joints and spine in axSpA [9,107-111,125-129]. The Spondyloarthritis Research Consortium of Canada and Berlin methods have been used as scoring systems for quantification and follow-up of lesions in the sacroiliac joints and spine on MRI [138-140]. Radiography Sacroiliac Joints There is no standard method of following patients with radiographs to evaluate for progression of structural changes [22], and the American College of Rheumatology recommends against routine radiographic follow-up given the lack of proven benefit [30]. Repeat radiographs can be obtained as necessary for counseling patients on the status and prognosis of their disease, although radiographs are more typically performed to evaluate the spine rather than the sacroiliac joints [30]. This is because of the low utility of sacroiliac joint radiographs for detecting disease progression based on the relatively poor intra- and interreader reliability of interpretation [141]. Radiographs can demonstrate evolving structural changes or bone formation, although these changes occur slowly over time at the sacroiliac joints, often requiring years to detect a change and prompting many authors to suggest a radiographic imaging interval of axSpA patients of no less than 2 years for assessment of disease progression [141-146]. There is evidence that patients on TNF-inhibitors may have slower progression of structural damage at the sacroiliac joints [147,148], although there is some disagreement in the literature [149].


Inflammatory Back Pain Known or Suspected Axial Spondyloarthropathy PCAs. Radiographic scoring systems, such as the Bath Ankylosing Spondylitis Radiology Index for the sacroiliac joints, have been utilized for quantification and follow-up of radiographic progression in patients over time [29,150]. Radiography Sacroiliac Joints and Spine Area of Interest There is no standard method of following patients with radiographs to evaluate for progression of structural changes [22], and the American College of Rheumatology recommends against routine follow-up given the lack of proven benefit [30]. Repeat radiographs can be obtained for counseling patients on the status and prognosis of their disease, although radiographs are more typically performed to evaluate the spine rather than the sacroiliac joints [30]. This is because of the low utility of sacroiliac joint radiographs for detecting disease progression based on the relatively poor intra- and interreader reliability of interpretation [141]. Radiographic follow-up can demonstrate evolving structural changes or bone formation, although these changes occur slowly over time at the sacroiliac joints and spine, often requiring years to detect a change and prompting some authors to suggest a radiographic imaging interval of axSpA patients of no less than 2 years for assessment of disease progression [141,143-145,151-153]. There is evidence that patients on TNF-inhibitors may have slower progression of structural damage at the sacroiliac joints and spine [148,154-156], although there is some disagreement in the literature [149]. Radiographic scoring systems, such as the Bath Ankylosing Spondylitis Radiology Index for the sacroiliac joints and the modified Stoke Ankylosing Spondylitis Spine Score for the spine, have been utilized for quantification and follow-up of radiographic progression over time [29,150,157]. US Sacroiliac Joints US of the sacroiliac joints is not utilized as a routine diagnostic tool in the assessment of treatment response or disease progression.


Inflammatory Back Pain Known or Suspected Axial Spondyloarthropathy PCAs. Importantly, a US evaluation is limited to the superficial posterior margins of the sacroiliac joints and spine, and therefore many structural details are not demonstrated. Many of the available studies examine the utility of Doppler evaluation. There is evidence in small studies that Doppler resistive indices at the sacroiliac joints increase following treatment with TNF-inhibitors [132,158,159], although more data are necessary to justify the routine use of US in this setting. US Sacroiliac Joints and Spine Area of Interest US of the sacroiliac joints is not utilized as a routine diagnostic tool in the assessment of treatment response or disease progression. Importantly, an US evaluation is limited to the superficial posterior margins of the sacroiliac joints and spine, and therefore many structural details are not demonstrated. Many of the available studies examine the utility of Doppler evaluation. There is evidence in small studies that Doppler-resistive indices at the sacroiliac joints increase following treatment with TNF-inhibitors [132,158,159], and there is limited data showing potentially similar findings in thoracolumbar paraspinal spondylitis [132], although more data are necessary to justify routine use of US in this setting. Variant 5: Axial spondyloarthritis with spine ankylosis. Suspected fracture. Initial imaging. The body regions covered in this clinical scenario are the cervical, thoracic, and lumbar spine. These body regions might be evaluated separately or in combination as guided by physical examination findings, patient history, and other available information. Inflammatory Back Pain Bone Scan with SPECT or SPECT/CT Spine Area of Interest Bone scintigraphy is not routinely obtained to evaluate for suspected fracture in axSpA patients with spine ankylosis, and there is no relevant literature supporting its use in this setting.


Inflammatory Back Pain Known or Suspected Axial Spondyloarthropathy PCAs. CT Spine Area of Interest CT and MRI are the imaging techniques of choice for definitive evaluation of the patient with ankylosis and suspected fracture [22,32]. CT can be performed rapidly in trauma patients and excellently depicts the complex structures of each vertebral column that can injured in this setting [31] and therefore is typically the preferred modality [22]. The sensitivities of CT and MRI for fracture detection are similar in the available small case series, notably with some fractures better detected on CT and some better detected on MRI, suggesting these modalities have a degree of complementary diagnostic utility [34,160,161]. CT, similar to MRI, has higher sensitivity for detection of fracture in the setting of ankylosis than radiographs [31,32,34,161]. The cervical spine is most frequently involved in a fracture [32,33,35]. The presence of two or more fractures is common [160], and therefore, the entire spine should be imaged to both ensure detection of the potential fracture(s) and to detect multilevel involvement [32]. Fluoride PET/CT Skull Base to Mid-Thigh F-18-fluoride PET/CT is not routinely obtained to evaluate for suspected fracture in axSpA patients with spine ankylosis, and there is no relevant literature supporting its use in this setting. MRI Spine Area of Interest CT and MRI are the imaging techniques of choice for definitive evaluation of the patient with ankylosis and suspected fracture [22,32]. Technical difficulties can be encountered during an MRI of some patients with spine ankylosis in the acute posttraumatic setting, including inability of patients to remain immobile during the examination, difficulty with coil selection, and motion artifact. These factors combined with varying degrees of spinal deformity and occasional lack of associated bone marrow edema at fracture sites can result in challenging interpretation [160]. Therefore, CT is typically the preferred modality in this setting [22].


Inflammatory Back Pain Known or Suspected Axial Spondyloarthropathy PCAs. The sensitivities of CT and MRI for fracture detection are similar in the available small case series, notably with some fractures better detected on CT and some better detected on MRI, suggesting these modalities have a degree of complementary diagnostic utility [34,160,161]. MRI, similar to CT, has higher sensitivity for detection of fracture in the setting of ankylosis than radiographs [32,34,161]. MRI can detect both osseous fractures as well as soft tissue injuries such as ligamentous disruption or spinal cord injury [31,34,160]. In the setting of neurologic deficit, MRI should be performed, either as the sole cross-sectional imaging modality or in addition to CT [22,162]. The cervical spine is most frequently involved by fracture [32,33,35]. The presence of two or more fractures is common [160], and therefore the entire spine should be imaged to both ensure detection of the potential fracture(s) and to detect multilevel involvement [32]. Radiography Spine Area of Interest Radiography of the spine can be considered as an initial imaging modality in patients with axSpA and suspected fracture [22], although fractures can be difficult to detect on radiographs in axSpA patients, especially in the setting of structural abnormalities and osteopenia, contributing further to an already inherent lower sensitivity of radiography for fracture detection compared with CT or MRI [31,32,34,160,161]. Negative radiographs in these patients should be followed by cross-sectional imaging. If obtained, radiographs should cover the entire spine in patients with ankylosis and suspected fracture because of the potential for multilevel fractures [32,160].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant.  Introduction/Background Antenatal hydronephrosis is the most frequent urinary tract anomaly detected on prenatal screening by ultrasonography (US). Antenatal hydronephrosis occurs approximately twice as often in males as in females [1-4]. With an estimated 4 million births per year in the United States, up to 80,000 fetal studies may detect antenatal hydronephrosis. Most antenatal hydronephrosis is transient with little long-term significance [5-8]. Few children with antenatal hydronephrosis, including some with ureteropelvic junction obstruction (UPJO), vesicoureteral reflux (VUR), and primary megaureter will have significant obstruction, develop symptoms or complications, which requires surgical intervention. Some male children will be diagnosed with more serious conditions, such as posterior urethral valves (PUV), which may require intervention. Early detection and treatment of obstructive uropathy is necessary to mitigate the potential morbidity from loss of renal function. During prenatal evaluation, most antenatal hydronephrosis is mild, and the cause cannot always be determined with certainty. As a result, postnatal evaluation of these children is frequently performed. In an effort to standardize grading of antenatal hydronephrosis, the Society for Fetal Urology (SFU) introduced a five point grading system in 1988, based on degree of pelvic and calyceal dilation and the thickness of the parenchyma overlying the calices [9]. Since its introduction, the SFU grading system has become the most widely used method to grade pediatric hydronephrosis [10]. Subsequently, several alternative classification schemes have also been devised [3,4,11,12].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Adherence to standardized reporting models is not well adopted according to a recent survey of pediatric radiologists [13,14], In order to increase standardization of reporting and care, a consensus group from many separate organizations recommended adoption of the urinary tract dilation (UTD) classification system which incorporates prenatal and postnatal imaging findings based on: 1) anterior-posterior renal pelvic diameter (APRPD); 2) calyceal dilation with distinction between central and peripheral calyceal dilation postnatally; 3) renal parenchymal thickness; 4) renal parenchymal appearance; 5) bladder abnormalities; and 6) ureteral abnormalities. For antenatal studies, the seventh US finding to report is the quantity of amniotic fluid [3]. This recently proposed grading classification system, as with any system, will require extensive evaluation to assess and confirm its usefulness in predicting clinical outcomes [3]. For the purposes of the current evaluation, degree of hydronephrosis is based on the SFU grading. The SFU system has been in use for a longer period of time and has good inter-rater reliability [3,15,16]. There are studies that have shown increased accuracy of hydronephrosis grading system if APRPD is measured [17,18]. We therefore have included an APRPD of >15 mm on postnatal imaging as a sign of severe hydronephrosis. Over time, the UTD classification system may predominate, but at present, familiarity with the SFU system is more widespread. Inclusion of the APRPD >15 mm conforms to the intermediate- to high-risk urinary tract dilation stratification [3]. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document. Reprint requests to: publications@acr.org


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. OR Discussion of Procedures by Variant Variant 1: Antenatal diagnosis of hydronephrosis. Initial neonatal imaging. US Kidneys and Bladder Retroperitoneal US in the immediate postnatal period evaluates for the presence and severity of underlying urologic abnormalities and therefore has a role in guiding management [3,6,12,19-25]. Because of the relative low urine production in newborns, initial imaging should be delayed at least 48 to 72 hours after birth [3,26-29]. Exceptions include newborns with severe, bilateral hydronephrosis and bladder abnormalities, oligohydramnios, or situations in which follow-up studies may be difficult to obtain. In these infants, earlier imaging is indicated [20,27,29,30]. Fluoroscopic Voiding Cystourethrography There is controversy regarding whether all children with antenatal hydronephrosis should undergo voiding cystourethrography (VCUG). A meta-analysis by the American Urology Association found that, on average, approximately 16% of neonates and infants with antenatal hydronephrosis will have VUR. The incidence of VUR was independent of degree of antenatal hydronephrosis, and a quarter of these were found to have no hydronephrosis on postnatal US [31]. There is disagreement over whether this VUR is clinically significant and therefore over the need for diagnosis. Some authors advocate VCUG for all infants with antenatal hydronephrosis, to guide treatment with prophylactic antibiotics [20,27,32,33]. However, currently, most authors (including the 2010 SFU consensus statement) recommend against routine VCUG for antenatal hydronephrosis [2,12,29,34,35]. This is largely because the benefit of prophylactic antibiotics in children with urinary tract infection (UTI) has not been clearly demonstrated and remains controversial. Some studies have suggested that prophylactic antibiotics may be beneficial in patients with VUR [36-38].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. The efficacy of prophylactic antibiotics in preventing UTIs or renal damage in patients with antenatal hydronephrosis, with or without VUR, is difficult to determine because of variability in methods and results [39]. In addition, most of the VUR spontaneously resolves [40]. One of the potential risks of VCUG is iatrogenic UTI. This was reported in about 2% of VCUG studies performed for evaluation of antenatal hydronephrosis [39]. Voiding Urosonography Multiple recent investigations evaluating real-time contrast-enhanced US techniques have demonstrated a high degree of diagnostic accuracy, and some demonstrated increased sensitivity as compared to fluoroscopic VCUG in the detection of VUR [41-45]. The main potential disadvantage of voiding urosonography is a lower anatomical detail of the bladder and urethra, and therefore it should not be used as the first study for male patients. Therefore, arguments for and against using voiding urosonography are similar to that of VCUG with the exception of male patients. Nuclear Medicine Cystography Some studies have suggested equal sensitivity for Tc-99m pertechnetate radionuclide cystography and VCUG [46], whereas others have indicated that radionuclide cystography has improved sensitivity for VUR in infants up to 1 year of age [47]. The main disadvantage of radionuclide cystography is that it does not provide anatomical details of the bladder and urethra and therefore should not be used as the first study for male patients. Therefore, arguments for and against using radionuclide cystography are similar to that of VCUG with the exception of male patients. DTPA Renal Scan There is no relevant literature to support the routine use of Tc-99m diethylenetriamine pentaacetic acid (DTPA) renal scan in the initial postnatal evaluation of antenatal hydronephrosis.


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. MAG3 Renal Scan There is no relevant literature to support the routine use of Tc-99m mercaptoacetyltriglycine (MAG3) diuretic renal scan in the initial postnatal evaluation of antenatal hydronephrosis. MRI Abdomen and Pelvis There is no relevant literature to support the routine use of MR urography (MRU) in the initial postnatal evaluation of antenatal hydronephrosis. Fluoroscopic Voiding Cystourethrography There is controversy regarding whether all children with antenatal hydronephrosis should undergo VCUG. A meta- analysis by the American Urology Association found that on average, approximately 16% of neonates and infants with antenatal hydronephrosis will have VUR. The incidence of VUR was independent of degree of antenatal hydronephrosis, and a quarter of these were found to have no hydronephrosis on postnatal US [31]. There is disagreement over whether this VUR is clinically significant and therefore over the need for diagnosis. Some authors advocate VCUG for all infants with antenatal hydronephrosis, to guide treatment with prophylactic antibiotics [20,27,32,33]. However, currently, most authors (including the 2010 SFU consensus statement) recommend against routine VCUG for antenatal hydronephrosis [2,12,29,34,35]. This is largely because the benefit of prophylactic antibiotic in children with UTI has not been clearly demonstrated [36]. The efficacy of prophylactic antibiotics in preventing UTIs or renal damage in patients with antenatal hydronephrosis, with or without VUR, is difficult to determine because of variability in methods and results [39]. In addition, most of the VUR spontaneously resolves [40]. One of the potential risks of VCUG is iatrogenic UTI. This was reported in about 2% of VCUG studies performed for evaluation of antenatal hydronephrosis [39].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Voiding Urosonography Multiple recent investigations evaluating real-time contrast-enhanced US techniques have demonstrated a high degree of diagnostic accuracy, and some demonstrated increased sensitivity as compared to fluoroscopic VCUG in the detection of VUR [41-45]. The main potential disadvantage of voiding urosonography is a lower anatomical detail of the bladder and urethra, and therefore it should not be used as the first study for male patients. Therefore, arguments for and against using voiding urosonography are similar to that of VCUG with the exception of male patients. Nuclear Medicine Cystography Some studies have suggested equal sensitivity for Tc-99m pertechnetate radionuclide cystography and VCUG [46], whereas others have indicated that radionuclide cystography has improved sensitivity for VUR in infants up to 1 year of age [47]. The main disadvantage of radionuclide cystography is that it does not provide anatomical details of the bladder and urethra and therefore should not be used as the first study for male patients. Therefore, arguments for and against using radionuclide cystography are similar to that of VCUG with the exception of male patients. DTPA Renal Scan There is no relevant literature to support the routine use of Tc-99m DTPA renal scan in the setting of a normal neonatal US. MAG3 Renal Scan There is no relevant literature to support the routine use of Tc-99m MAG3 diuretic renal scan in the setting of a normal neonatal US. MRI Abdomen and Pelvis There is no relevant literature to support the routine use of MRU in the in the setting of a normal neonatal US. Fluoroscopic Voiding Cystourethrography There is controversy regarding whether all children with antenatal hydronephrosis should undergo VCUG. A meta- analysis by the American Urology Association found that, on average, approximately 16% of neonates and infants with antenatal hydronephrosis will have VUR.


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. The incidence of VUR was independent of degree of antenatal hydronephrosis, and a quarter of these were found to have no hydronephrosis on postnatal US [31]. There is disagreement over whether this VUR is clinically significant and therefore over the need for diagnosis. Some authors advocate VCUG for all infants with antenatal hydronephrosis, to guide treatment with prophylactic antibiotics [20,27,32,33]. However, currently, most authors (including the 2010 SFU consensus statement) recommend against routine VCUG for antenatal hydronephrosis [2,12,29,34,35]. This is largely because the benefit of prophylactic antibiotic in children with UTI has not been clearly demonstrated [36]. The efficacy of prophylactic antibiotics in preventing UTIs or renal damage in patients with antenatal hydronephrosis, with or without VUR, is difficult to determine because of variability in methods and results [39]. In addition, most of the VUR spontaneously resolves [40]. One of the potential risks of VCUG is iatrogenic UTI. This was reported in about 2% of VCUG studies performed for evaluation of antenatal hydronephrosis [39]. Voiding Urosonography Multiple recent investigations evaluating real-time contrast-enhanced US techniques have demonstrated a high degree of diagnostic accuracy, and some demonstrated increased sensitivity as compared to fluoroscopic VCUG in the detection of VUR [41-45]. The main potential disadvantage of voiding urosonography is a lower anatomical detail of the bladder and urethra, and therefore it should not be used as the first study for male patients. Therefore, arguments for and against using voiding urosonography are similar to that of VCUG with the exception of male patients. Nuclear Medicine Cystography Some studies have suggested equal sensitivity for Tc-99m pertechnetate radionuclide cystography and VCUG [46], whereas others have indicated that radionuclide cystography has improved sensitivity for VUR in infants up to 1 year of age [47].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. The main disadvantage of radionuclide cystography is that it does not provide anatomical details of the bladder and urethra and therefore should not be used as the first study for male patients. Therefore, arguments for and against using radionuclide cystography are similar to that of VCUG with the exception of male patients. DTPA Renal Scan There is no relevant literature to support the routine use of Tc-99m DTPA renal scan as the first imaging in the evaluation of mild antenatal hydronephrosis, because there is low risk of underlying anatomic abnormality such as UPJO in the setting of mild hydronephrosis. MAG3 Renal Scan There is no relevant literature to support the routine use of Tc-99m MAG3 diuretic renal scan as the first imaging in the evaluation of mild antenatal hydronephrosis, because there is low risk of underlying anatomic abnormality such as UPJO in the setting of mild hydronephrosis. MRI abdomen and pelvis There is no relevant literature to support the routine use of MRU in the initial evaluation of mild antenatal hydronephrosis. VUR can be either primary or secondary to other urologic abnormalities. In male patients with moderate or severe hydronephrosis found on neonatal US, VCUG has a role in the evaluation of urologic abnormalities that may need immediate care, and bladder outlet obstruction from PUV must be excluded [12,20,28,29,50,57]. The catheter placed for initial bladder decompression can be used for this study. There is no need to remove the bladder catheter to assess for PUV [58]. Frequently, the study will show VUR in addition to bladder wall thickening and the dilated posterior urethra. When the diagnosis of PUV is made, immediate referral to urology is needed. Furthermore, it can reveal other anomalies such as a duplex collecting system, which helps to determine whether the reflux is primary or secondary. Other infants with severe or bilateral moderate antenatal hydronephrosis may have VUR in isolation.


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. There is higher risk for UTI in children with VUR [59]. Although the benefit of prophylactic antibiotics in this population is unknown, some authors recommend beginning antibiotics on these patients [26,60]. Voiding Urosonography Multiple recent investigations evaluating real-time contrast-enhanced US techniques have demonstrated a high degree of diagnostic accuracy, and some demonstrated increased sensitivity compared to fluoroscopic VCUG in the detection of VUR [41-45]. However, given the significant disadvantage of voiding urosonography in providing lower anatomical detail of the bladder and urethra, it should not be used as the first study for male patients. Nuclear Medicine Cystography Although some studies have suggested equal sensitivity for Tc-99m pertechnetate radionuclide cystography and VCUG [46], it does not provide sufficient anatomical detail of the bladder and urethra and therefore should not be used as the first study for male patients. DTPA Renal Scan Tc-99m DTPA is excreted primarily by glomerular filtration. Its extraction fraction is approximately 20% accounting for greater background, versus renal, activity compared to MAG3 [61]. Tc-99m DTPA renal scan provides information on renal function and urinary tract drainage based on split renal function and renal washout curves and can be useful for the evaluation of severe grade 3 and 4 hydronephrosis in concert with VCUG [20,29,53,62,63]. Given the lower glomerular filtration rate in newborns, these examinations are frequently delayed until at least 2 months of age [29,63-65]. However, because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc-99m MAG3 is preferred over Tc-99m DTPA in patients with suspected obstruction or impaired renal function [61]. MAG3 Renal Scan Tc-99m MAG3 is primarily excreted through active renal tubular transport, and its extraction fraction is 40% to 50% [61].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. This greater extraction fraction, versus DTPA, accounts for less background, versus renal, activity compared to DTPA. Because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc-99m MAG3 is preferred over Tc-99m DTPA in patients with suspected obstruction or impaired renal function [61]. Tc-99m MAG3 renal scan is useful for the evaluation of severe grade 3 and 4 hydronephrosis and may be performed in concert with a VCUG study [20,29,53,62,63]. Tc-99m MAG3 renal scan provides information on renal function and urinary tract drainage based on split renal function [61]. Diuretic renal scan is used for diagnosis of multiple causes of obstruction, including primary obstructing megaureter [52,66-68]. Approximately 5% to 10% of antenatal hydronephrosis is attributable to primary megaureter [4,69] diagnosed by persistent ureteral dilation (>7 mm). Primary megaureter is classified according to the presence or absence of reflux and obstruction. Most will resolve spontaneously [20,70-72]. Surgical intervention is decided based on evidence of obstruction and depends upon T1/2 of time activity curve (T1/2 >20 minutes), decreased renal function (<40% differential renal function), deteriorating function (>5% change on consecutive renal scans), or worsening drainage on serial imaging. Tc-99m MAG3 renal scan can be used to monitor function over time, with a decrease in differential renal function on the affected side often serving as an indicator of a need for intervention [55,73]. MRI Abdomen and Pelvis There is no consensus on the role of MRU, performed without and with intravenous (IV) contrast, in patients with moderate to severe postnatal hydronephrosis especially before VCUG is performed.


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Although MRU is not routinely recommended in the initial workup of antenatal hydronephrosis, some authors have argued that it can add value through improved anatomical imaging, for example, in the evaluation of hydronephrosis in the setting of atypical urinary tract anatomy, such as certain duplicated collecting systems or renal dysgenesis [74]. MRU can also adequately assess degree of obstruction [75]. One potential limitation of MRU is that there are systematic differences in estimation of split renal function compared with the gold standard MAG-3 renal scan in kidneys with severely diminished renal function [75] and kidneys with severe hydronephrosis [76]. VUR can be either primary or secondary to other urologic abnormalities. In patients with moderate or severe hydronephrosis found on neonatal US, VCUG has a role in the evaluation of urologic abnormalities that may need immediate care [12,20,28,29,50,57]. Furthermore, it can reveal other anomalies, such as a duplex collecting system, which help to determine whether the reflux is primary or secondary. Other infants with severe or bilateral moderate antenatal hydronephrosis may have VUR in isolation. There is higher risk for UTI in children with VUR [59]. Although the benefit of prophylactic antibiotics in this population is unknown, some authors recommend beginning antibiotics on these patients [26,60]. Nuclear Medicine Cystography Some studies have suggested equal sensitivity for Tc-99m pertechnetate radionuclide cystography and VCUG [46], whereas others have indicated that radionuclide cystography has improved sensitivity for VUR in infants up to 1 year of age [47]. Arguments for and against using radionuclide cystography are similar to that of VCUG for the female patient. DTPA Renal Scan Tc-99m DTPA is excreted primarily by glomerular filtration. Its extraction fraction is approximately 20% accounting for greater background, versus renal, activity compared to MAG3 [61].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Tc-99m DTPA renal scan provides information on renal function and urinary tract drainage based on split renal function and renal washout curves and can be useful for the evaluation of severe grade 3 and 4 hydronephrosis in concert with VCUG [20,29,53,62,63]. Given the lower glomerular filtration rate in newborns, these examinations are frequently delayed until at least 2 months of age [29,63-65]. However, because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc-99m MAG3 is preferred over Tc-99m DTPA in patients with suspected obstruction or impaired renal function [61]. MAG3 Renal Scan Tc-99m MAG3 is primarily excreted through active renal tubular transport, and its extraction fraction is 40% to 50% [61]. This greater extraction fraction, versus DTPA, accounts for less background, versus renal, activity compared to DTPA. Because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc-99m MAG3 is preferred over Tc-99m DTPA in patients with suspected obstruction or impaired renal function [61]. Tc-99m MAG3 renal scan is useful for the evaluation of severe grade 3 and 4 hydronephrosis and may be performed in concert with a VCUG study [20,29,53,62,63]. Tc-99m MAG3 renal scan provides information on renal function and urinary tract drainage based on split renal function [61]. Diuretic renal scan is used for diagnosis of multiple causes of obstruction, including primary obstructing megaureter [52,66-68]. Approximately 5% to 10% of antenatal hydronephrosis is attributable to primary megaureter [4,69] diagnosed by persistent ureteral dilation (>7 mm). Primary megaureter is classified according to the presence or absence of reflux and obstruction. Most will resolve spontaneously [20,70-72].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Surgical intervention is decided based on evidence of obstruction and depends upon T1/2 of time activity curve (T1/2 >20 minutes), decreased renal function (<40% differential renal function), deteriorating function (>5% change on consecutive renal scans), or worsening drainage on serial imaging. Tc-99m MAG3 renal scan can be used to monitor function over time, with a decrease in differential renal function on the affected side often serving as an indicator of a need for intervention [55,73]. MRI Abdomen and Pelvis There is no consensus on the role of MRU, performed without and with IV contrast, in patients with moderate to severe postnatal hydronephrosis especially before VCUG is performed. Although MRU is not routinely recommended in the initial workup of antenatal hydronephrosis, some authors have argued that it can add value through improved anatomical imaging, for example, in the evaluation of hydronephrosis in the setting of atypical urinary tract anatomy, such as certain duplicated collecting systems or renal dysgenesis [74]. MRU can also adequately assess degree of obstruction [75]. One potential limitation of MRU is inaccurate estimation of split renal function compared with renal scan in kidneys with severely diminished renal function [75] and kidneys with severe hydronephrosis [76]. should be considered [6,29,53,77]. Of the causes of hydronephrosis, UPJO accounts for approximately 10% to 65% of cases and in 90% of cases the obstruction is unilateral [2,4,22,48]. As the severity of hydronephrosis increases, the risk of UPJO also increases, and as much as 35% of significant hydronephrosis (>10 mm APRPD postnatally) was attributable to UPJO in one study. Lee et al [51] showed a 54% risk of UPJO in severe (>15 mm APRPD postnatally) urinary tract dilation. Even in the setting of abnormal findings on initial neonatal US, further follow- up US between 1 and 6 months may be useful to re-evaluate a dilated urinary tract after bladder catheterization [1,21,23,53-55].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. DTPA Renal Scan Tc-99m DTPA is excreted primarily by glomerular filtration. Its extraction fraction is approximately 20% accounting for greater background, versus renal, activity compared to MAG3 [61]. Tc-99m DTPA renal scan provides information on renal function and urinary tract drainage based on split renal function and renal washout curves and can be useful for the evaluation of severe grade 3 and 4 hydronephrosis [20,29,53,62,63]. Given the lower glomerular filtration rate in newborns, these examinations are frequently delayed until at least 2 months of age [29,63-65]. However, because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc-99m MAG3 is preferred over Tc-99m DTPA in patients with suspected obstruction or impaired renal function [61]. MAG3 Renal Scan Tc-99m MAG3 is primarily excreted through active renal tubular transport, and its extraction fraction is 40% to 50%. This greater extraction fraction, versus DTPA, accounts for less background, versus renal, activity compared to DTPA. Because of its rapid renal clearance and primary excretion by the tubules on which furosemide acts, Tc- 99m MAG3 is preferred over Tc-99m DTPA in patient with suspected obstruction or impaired renal function [61]. Tc-99m MAG3 renal scan provides information on split renal function and urinary tract drainage based on renal washout curve [3,22,27,28]. Diuretic renal scan is used for diagnosis of multiple causes of obstruction, including primary obstructing megaureter [52,66-68]. Approximately 5% to 10% of antenatal hydronephrosis is attributable to primary megaureter [4,69] diagnosed by persistent ureteral dilation (>7 mm). Primary megaureter is classified according to the presence or absence of reflux and obstruction. Most will resolve spontaneously [20,70-72].


Antenatal Hydronephrosis Infant

Antenatal Hydronephrosis Infant. Surgical intervention is decided based on evidence of obstruction based on T1/2 of time activity curve (T1/2 >20 minutes), decreased renal function (<40% differential renal function), deteriorating function (>5% change on consecutive renal scans), or worsening drainage on serial imaging [55,73]. Tc-99m MAG3 renal scan can be used to monitor function over time, with a decrease in differential renal function on the affected side often serving as an indicator of a need for intervention [55,73]. MRI Abdomen and Pelvis There is no consensus on the role of MRU, performed without and with IV contrast, in patients with moderate to severe postnatal hydronephrosis. Although MRU is not routinely recommended in the initial workup of antenatal hydronephrosis, some authors have argued that it can add value through improved anatomical imaging, for example, in the evaluation of hydronephrosis in the setting of atypical urinary tract anatomy, such as certain duplicated collecting systems or renal dysgenesis [74]. MRU can also adequately assess degree of obstruction [75]. One potential limitation of MRU is that there are systematic differences in estimation of split renal function compared with renal scan in kidneys with severely diminished renal function and kidneys with severe hydronephrosis [76]. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch. acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation. For additional information on the Appropriateness Criteria methodology and other supporting documents go to www. acr.org/ac. Appropriateness Category Names and Definitions Relative Radiation Level Information Potential adverse health effects associated with radiation exposure are an important factor to consider when selecting the appropriate imaging procedure.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge.  Special Imaging Considerations In 2018, Schulz-Wendtland et al [25] first described a technique combining digital breast tomosynthesis (DBT) and ductography and evaluated 5 women with pathologic nipple discharge. They found that DBT-ductography performed comparably to high-resolution ultrasound (US) in identifying suspicious imaging lesions. In 2020 Moschetta et al [26] used this nascent technique on 49 consecutive patients with spontaneous, unilateral, single- pore discharge and inconclusive conventional digital mammography and US. In this series, they compared DBT- Reprint requests to: publications@acr.org Evaluation of Nipple Discharge ductography with conventional full-field galactography and found improved sensitivity (95% versus 77%) and accuracy (96% versus 80%) with identical specificity (80%). OR Discussion of Procedures by Variant Variant 1: Adult female or male or transfeminine (male-to-female) or transmasculine (female-to-male). Physiologic nipple discharge. Initial imaging. Physiologic nipple discharge is defined as bilateral, originating from multiple ducts, white/green/yellow in color, or milky in appearance [27]. It tends to occur only when provoked [8]. Many studies have shown physiologic nipple discharge to be benign, with no association within situ or invasive carcinoma [9,28,29]. Mammography Diagnostic If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. Digital Breast Tomosynthesis Diagnostic If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. US Breast If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Ductography If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. MRI Breast If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. FDG-PET Breast Dedicated If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. Image-guided Core Biopsy Breast Image-guided core biopsy is not required for the evaluation of physiologic nipple discharge in the female patient. Image-Guided Fine Needle Aspiration Breast Image-guided fine-needle aspiration (FNA) is not required for the evaluation of physiologic nipple discharge in the female patient. Sestamibi MBI If patient history and physical examination demonstrate physiologic nipple discharge and routine screening mammography is up to date, no further radiologic investigation is needed [28,29]. Evaluation of Nipple Discharge Variant 2: Adult male or female 40 years of age or older. Pathologic nipple discharge. Initial imaging. Mammography Diagnostic Mammography is the first-line imaging modality for evaluation of pathologic nipple discharge in male and female patients in this age group [30]. Although 3% to 29% of pathologic nipple discharge is due to an underlying breast cancer, full-field mammography often does not demonstrate these lesions because they may be very small, contain no calcifications, or are completely intraductal [1-3]. To better evaluate the subareolar breast in patients with an asymmetry/focal asymmetry or suspicious microcalcifications, additional mammographic views with spot compression and magnification may be needed [31]. Most cases of pathologic nipple discharge are due to a benign intraductal papilloma [32].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. When visible on mammography, imaging findings of papilloma include asymmetrically dilated ducts, a circumscribed benign- appearing subareolar mass, or grouped microcalcifications [1]. Up to 12% of patients with ductal carcinoma in situ (DCIS) present with nipple discharge [33]. DCIS is usually detected mammographically as fine, linear, discontinuous, and branching microcalcifications in linear, ductal, or segmental distribution and less often as a mass, asymmetry/focal asymmetry, or architectural distortion on mammography [11]. The mammographic features of invasive carcinomas are well known, including a mass of various margin characteristics with or without microcalcifications or an asymmetry, focal asymmetry, or architectural distortion [34]. For detection of malignancy (DCIS and invasive cancer), the reported sensitivity of mammography varies widely between 15% and 68%, with a specificity between 38% and 98% [3,9,23,28]. In one study, the positive predictive value (PPV) was 42%, and the negative predictive value (NPV) was 90% [23]. Malignant and high-risk lesions are identified by mammography with a reported sensitivity of 10% to 26%, specificity of 94% to 95%, PPV of 18%, and NPV of 88% [3,16]. The possible causes of the wide variation in reported sensitivity include differences in imaging technology (digital versus film-screen mammography) and varied breast density among different cohorts of patients. In a study of 106 patients >30 years of age with pathologic nipple discharge, Gray et al [28] showed the risk of carcinoma to be 3% with a negative mammogram and 0% when both mammogram and subareolar US were negative. Although low in sensitivity and PPV, mammography remains useful in the evaluation of pathologic nipple discharge because of its high specificity and high NPV.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise is assessing the symptomatic breast [35,36]. US Breast US is useful in identifying invasive cancer and assessing extent of disease but has a diminished sensitivity for detecting DCIS [9,12,37,38]. In patients with pathologic nipple discharge, US identifies lesions not visible on mammography 63% to 69% of the time [30,39]. US adds specificity for some lesions when compared with mammography if it identifies the mammographic finding as a simple cyst or duct ectasia. US expands on ductography in its ability to visualize and detect abnormalities in multiple rather than single ducts [24]. Although more sensitive than mammography, US suffers from lower specificity in differentiating benign versus malignant lesions [9]. False-positive US results may be due to volume averaging with the ductal wall in a tortuous duct, intraductal and periductal fibrosis, adherent blood clots, or inspissated debris [31]. Previous studies have also reported mammography and US to be unreliable in predicting histology in patients with pathologic nipple discharge, which underscores the necessity of histological diagnosis [17,23]. In male and female patients, US is useful in identifying and assessing lesions and for biopsy guidance [40]. Ductography Ductography may demonstrate small lesions and localize the duct responsible for the nipple discharge. Ductography is minimally invasive, may be uncomfortable, and can be time-consuming. The procedure is technically challenging with 10% to 15% of cases resulting in inadequate or incomplete results [41,42]. The discharge must be present on Evaluation of Nipple Discharge the day of ductography so that a cannula can be placed in the appropriate duct.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Failure to cannulate the discharging duct may lead to a false negative [43]. Ductography is not recommended in lactating women or patients with active mastitis. Known hypersensitivity to iodinated contrast agents is a relative contraindication. Findings on ductography suggestive of malignant or papillary lesions include intraductal filling defect, partial or complete obstruction of a duct, duct expansion or distortion, and duct wall irregularity [1]. In patients with pathologic nipple discharge and a negative mammogram and US, Morrogh et al [44] reported the PPV and NPV of ductography for detection of cancer and high-risk lesions to be 19% and 63%, respectively. In the setting of negative standard evaluations, ductography localized 76% of otherwise occult malignant/high-risk lesions and 91% of benign lesions [39]. When the standard evaluation is positive, ductography facilitated preoperative localization of the causative lesion in 78% of cases [39]. For detection of cancer in patients with pathologic nipple discharge, 2 studies showed the sensitivity, specificity, PPV, and NPV of ductography to be 75% to 100%, 6% to 49%, 16% to 18%, and 93% to 100%, respectively [16,23]. For detection of high-risk lesions, Adepoju et al [16] reported the sensitivity, specificity, PPV, and NPV of ductography to be 75%, 53%, 22%, and 92%, respectively. Ductography is more sensitive than mammography and US but has lower specificity than both modalities. A negative ductogram does not reliably exclude an underlying cancer or high-risk lesion, with the false-negative rate reported to be as high as 20% to 30% [44]. As such, the primary value of ductography is to localize intraductal lesions and assist in surgery [45]. A study found that patients who underwent ductography-guided operations or any other surgical procedure with image guidance of the lesion were significantly more likely to have a specific underlying lesion identified than patients who underwent central duct excision alone [23,42].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Contrast-enhanced breast MRI has high sensitivity for detecting benign papillary lesions as well as in situ and invasive carcinoma [3]. Furthermore, MRI allows identification of index lesions in peripheral ducts that are beyond the area normally encompassed by terminal duct excision, ductography, or targeted US [44]. Index or synchronous lesions found on MRI alone can be percutaneously biopsied with MRI guidance to allow for single-stage definitive surgical management (if malignant) or potentially to avoid unnecessary surgical excision for some benign lesions. In general, MRI may be considered in cases in which mammography and US have failed to identify an underlying cause of pathologic nipple discharge [3,44,48-50]. The sensitivities of breast MRI for detecting the cause of the pathologic nipple discharge are 86% to 100% for invasive cancer and 40% to 100% for noninvasive disease [3,12,44,49,51,52]. Bahl et al [52] reported the sensitivity, specificity, PPV, and NPV of MRI for detecting malignancy in patients with pathologic nipple discharge to be 100%, 68%, 37%, and 100%, respectively. Several studies have shown that MRI has higher sensitivity and specificity than US and ductography for lesion detection and may be an alternative to ductography [12,32,48,49]. However, a study by van Gelder et al [51] asserted that MRI has limited added value in patients with unilateral bloody nipple discharge who showed no signs of a malignancy on conventional diagnostic examinations, because malignancy was demonstrated in <2% of their cases. Despite the high sensitivity of breast MRI, it is not indicated as initial imaging in a patient with pathologic nipple discharge. FDG-PET Breast Dedicated High-resolution cameras specifically designed for breast imaging have improved detection of small and noninvasive carcinomas. However, specific research evaluating women with nipple discharge is lacking [41,53].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Currently, there is no relevant literature for the use of fluorine-18-2-fluoro-2-deoxy-D-glucose (FDG)-PET in the evaluation of a male or female patient with pathologic nipple discharge. Image-Guided Core Biopsy Breast Previous studies showed that mammography, US, and ductography are unreliable in predicting histology in patients with pathologic nipple discharge [17,23,44], which underscores the importance of histological diagnosis of lesions identified on imaging. The biopsy procedures may be guided by stereotactic mammography, US, ductography, or MRI, depending on the imaging modality that best depicts the lesion. CNB is preferred over FNA because the larger gauge needle improves sampling [54,55]. Placement of a tissue marker at the end of the biopsy allows for needle Evaluation of Nipple Discharge localization and excision if the biopsied lesion yields malignant or high-risk histology. Vacuum-assisted CNB is particularly useful in assuring complete sampling of small intraductal papillary lesions [24]. Although biopsy is a diagnostic procedure, the process of removing enough of the intraductal papillary lesion during vacuum-assisted core biopsy may be therapeutic and will lead to permanent cessation of nipple discharge in 90% to 97.2% of patients [24,56]. However, Reiner et al [57] cautioned that ductography-guided 11-gauge vacuum-assisted stereotactic biopsy should not be used as a substitute for surgical duct excision in cases of pathologic nipple discharge with abnormalities on ductography because of the high underestimation rate (50%) for high-risk lesions and DCIS, false- negative rate (7%), and histopathological detection of lesion remnants in every case. Papillomas are historically considered high-risk lesions, with reported rates of upgrade to malignancy between 3% and 14% [58,59]. The management of papillomas diagnosed on CNB is controversial and varies by institution [60].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Because papillomas diagnosed on CNB are often excised, excisional biopsy instead of CNB may be useful when a papillary lesion is anticipated based on imaging findings. A recent study suggests that patients with nonbloody pathologic nipple discharge, a benign CNB, or normal imaging (cancer risk <2%) may be considered for nonoperative management if they do not have risk factors such as prior ipsilateral breast cancer, BRCA mutation, or atypia on CNB [61]. In addition, US does not reliably distinguish between benign and malignant small intraductal lesions [9]. Therefore, the decision to perform percutaneous biopsy versus major duct excision should involve the patient and their health care provider. Image-guided CNB is equally useful in male patients for obtaining tissue diagnosis and assisting in patient management [40]. Image-guided CNB is not indicated as the initial examination to evaluate pathologic nipple discharge. Image-Guided Fine Needle Aspiration Breast Once a suspicious lesion that is likely responsible for the pathologic nipple discharge is identified on imaging, image-guided FNA or CNB can be performed for histological diagnosis. Although some institutions demonstrate good results using FNA, larger series have shown that core biopsy is superior to FNA in terms of sensitivity, specificity, and correct histological grading of a lesion [54,55]. Image-guided FNA is not indicated as the initial examination to evaluate pathologic nipple discharge. Sestamibi MBI There is no relevant literature to support the use of molecular breast imaging (MBI) in the evaluation of a male or female patient with pathologic nipple discharge. Mammography Diagnostic The sensitivity of US for palpable or nonpalpable breast cancer is higher than that of mammography (95.7% versus 60.9%) for women 30 to 39 years of age [63,64]. Either mammography or US may be used as the initial imaging modality, on the basis of institutional preference and case-by-case consideration.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. However, mammography has its value in detecting suspicious microcalcifications, given the high incidence of patients with DCIS presenting with nipple discharge. Evaluation of Nipple Discharge Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise is assessing the symptomatic breast [35,36]. US Breast The sensitivity of US for palpable or nonpalpable breast cancer is higher than that of mammography (95.7% versus 60.9%) for women 30 to 39 years of age [63,64]. Hence, US may be useful as the initial imaging modality, with mammography added when necessary. Ductography Ductography may demonstrate small lesions and localize the duct responsible for the nipple discharge. Ductography is minimally invasive, may be uncomfortable, and can be time-consuming. The procedure is technically challenging with 10% to 15% of cases resulting in inadequate or incomplete results [41,42]. The discharge must be present on the day of ductography so that a cannula can be placed in the appropriate duct. Failure to cannulate the discharging duct may lead to a false negative [43]. Ductography is not recommended in lactating women or patients with active mastitis. Known hypersensitivity to iodinated contrast agents is a relative contraindication. Findings on ductography suggestive of malignant or papillary lesions include intraductal filling defect, partial or complete obstruction of a duct, duct expansion or distortion, and duct wall irregularity [1]. In patients with pathologic nipple discharge and a negative mammogram and US, Morrogh et al [44] reported the PPV and NPV of ductography for the detection of cancer and high-risk lesions to be 19% and 63%, respectively.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. In the setting of negative standard evaluations, ductography localized 76% of otherwise occult malignant/high-risk lesions and 91% of benign lesions [39]. When the standard evaluation is positive, ductography facilitated preoperative localization of the causative lesion in 78% of cases [39]. For detection of cancer in patients with pathologic nipple discharge, 2 studies showed the sensitivity, specificity, PPV, and NPV of ductography to be 75% to 100%, 6% to 49%, 16% to 18%, and 93% to 100%, respectively [16,23]. For detection of high-risk lesions, Adepoju et al [16] reported the sensitivity, specificity, PPV, and NPV of ductography to be 75%, 53%, 22%, and 92%, respectively. Ductography is more sensitive than mammography and US but has a lower specificity than both modalities. A negative ductogram does not reliably exclude an underlying cancer or high-risk lesion, with the false-negative rate reported to be as high as 20% to 30% [44]. As such, the primary value of ductography is to localize intraductal lesions and assist in surgery [45]. A study found that patients who underwent ductography-guided operations or any other surgical procedure with image guidance of the lesion were significantly more likely to have a specific underlying lesion identified than patients who underwent central duct excision alone [23,42]. At this time, there is no relevant literature available for use of ductography for evaluation of a male patient with nipple discharge. Contrast-enhanced breast MRI has a high sensitivity for detecting benign papillary lesions as well as in situ and invasive carcinoma [3]. Furthermore, MRI allows for the identification of index lesions in peripheral ducts that are beyond the area normally encompassed by terminal duct excision, ductography, or targeted US [44].


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Index or synchronous lesions found on MRI alone can be percutaneously biopsied with MRI guidance to allow for single- stage definitive surgical management (if malignant) or potentially to avoid unnecessary surgical excision for some benign lesions. In general, MRI should be considered in cases in which mammography and US have failed to identify an underlying cause of pathologic nipple discharge [3,44,48-50]. The sensitivities of breast MRI for detecting the cause of the pathologic nipple discharge are 86% to 100% for invasive cancer and 40% to 100% for noninvasive disease [3,12,44,49,51,52]. Bahl et al [52] reported the sensitivity, specificity, PPV, and NPV of MRI for detecting malignancy in patients with pathologic nipple discharge to be 100%, 68%, 37%, and 100%, respectively. Several Evaluation of Nipple Discharge studies have shown that MRI has a higher sensitivity and specificity than US and ductography for lesion detection and may be an alternative to ductography [12,32,48,49]. However, a study by van Gelder et al [51] asserted that MRI has limited added value in patients with unilateral bloody nipple discharge who showed no signs of a malignancy on conventional diagnostic examinations, because malignancy was demonstrated in <2% of their cases. At this time, there is no relevant literature available for use of MRI for evaluation of a male patient with nipple discharge. FDG-PET Breast Dedicated High-resolution cameras specifically designed for breast imaging have improved detection of small and noninvasive carcinomas. However, specific research evaluating women with nipple discharge is lacking [41,53]. Currently, there is no relevant literature for the use of FDG-PET in the evaluation of a male or female patient with pathologic nipple discharge.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Image-Guided Core Biopsy Breast Previous studies showed that mammography, US, and ductography are unreliable in predicting histology in patients with pathologic nipple discharge [17,23,44], which underscores the importance of histological diagnosis of lesions identified on imaging. The biopsy procedures may be guided by stereotactic mammography, US, ductography, or MRI, depending on the imaging modality that best depicts the lesion. CNB is preferred over FNA because the larger gauge needle improves sampling [54,55]. Placement of a tissue marker at the end of the biopsy allows for needle localization and excision if the biopsied lesion yields malignant or high-risk histology. Vacuum-assisted CNB is particularly useful in assuring complete sampling of small intraductal papillary lesions [24]. Although biopsy is a diagnostic procedure, the process of removing enough of the intraductal papillary lesion during vacuum-assisted core biopsy may be therapeutic and will lead to permanent cessation of nipple discharge in 90% to 97.2% of patients [24,56]. However, Reiner et al [57] cautioned that ductography-guided 11-gauge vacuum-assisted stereotactic biopsy should not be used as a substitute for surgical duct excision in cases of pathologic nipple discharge with abnormalities on ductography because of the high underestimation rate (50%) for high-risk lesions and DCIS, false- negative rate (7%), and histopathological detection of lesion remnants in every case. Papillomas are historically considered high-risk lesions, with reported rates of upgrade to malignancy between 3% and 14% [58,59]. The management of papillomas diagnosed on CNB is controversial and varies by institution [60]. Because papillomas diagnosed on CNB are often excised, excisional biopsy instead of CNB may be useful when a papillary lesion is anticipated based on imaging findings.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. A recent study suggests that patients with nonbloody pathologic nipple discharge, a benign CNB, or normal imaging (cancer risk <2%) may be considered for nonoperative management if they do not have risk factors such as prior ipsilateral breast cancer, BRCA mutation, or atypia on CNB [61]. In addition, US does not reliably distinguish between benign and malignant small intraductal lesions [9]. Therefore, the decision to perform percutaneous biopsy versus major duct excision should involve the patient and their health care provider. Image-guided CNB is equally useful in male patients for obtaining tissue diagnosis and assisting in patient management [40]. Image-guided CNB is not indicated as the initial examination to evaluate pathological nipple discharge. Image-Guided Fine Needle Aspiration Breast Once a suspicious lesion that is likely responsible for the pathologic nipple discharge is identified on imaging, image-guided FNA or CNB can be performed for histological diagnosis. Although some institutions demonstrate good results using FNA, larger series have shown that core biopsy is superior to FNA in terms of sensitivity, specificity, and correct histological grading of a lesion [54,55]. Image-guided FNA is not indicated as the initial examination to evaluate pathological nipple discharge. Sestamibi MBI There is no relevant literature to support the use of MBI in the evaluation of a male or female patient with pathologic nipple discharge. Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise in assessing the symptomatic breast [35,36]. Ductography There is no relevant literature to support the use of ductography for the evaluation of male patients with nipple discharge.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. MRI Breast There is no relevant literature to support the use of MRI for the evaluation of male patients with nipple discharge. FDG-PET Breast Dedicated There is no relevant literature to support the use of FDG-PET for the evaluation of male patients with nipple discharge. Image-guided Core Biopsy Breast There is no relevant literature to support the use of core biopsy for the evaluation of male patients with nipple discharge. However, if an imaging abnormality is identified, US may be used to direct biopsy. Image-Guided Fine Needle Aspiration Breast There is no relevant literature to support the use of image-guided FNA for the evaluation of male patients with nipple discharge. Sestamibi MBI There is no relevant literature to support the use of MBI for the evaluation of male patients with nipple discharge. Variant 5: Adult female younger than 30 years of age. Pathologic nipple discharge. Initial imaging. The probability of a woman developing breast cancer over the next decade increases with age; the risk is 1 in 1,681 at 20 years of age, 1 in 232 at 30 years of age, and 1 in 69 at 40 years of age [62]. Breast cancer is rare in women <30 years of age, with the exception of those with a genetic predisposition or prior mantle radiation to the chest. In a study by Seltzer et al [66] on the significance of age in patients with nipple discharge, malignancy was found in 1 of 10 patients <30 years of age. However, caution should be exercised interpreting these results given a very small sample size and the possible inclusion of high-risk patients. Mammography Diagnostic Most breast lesions in young women are not visualized on mammography [67,68] because of the low incidence of breast cancer (0.4% or lower) in women <30 years of age. US is most useful for initial imaging in this population; however, diagnostic mammography may be useful when US shows a suspicious finding.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise in assessing the symptomatic breast [35,36]. Evaluation of Nipple Discharge US Breast Yue et al [69] studied 955 women <25 years of age who presented with breast symptoms including palpable mass, pain, and nipple discharge. US was performed in 692 patients and was normal/negative in 671 patients and indeterminate in 21 patients. No cancer was found in this group via biopsy or clinical follow-up. However, it is unknown how many of these patients had pathologic or physiologic discharge. Ductography There is no relevant literature to support the use of ductography in women <30 years of age with symptoms of pathologic nipple discharge. MRI Breast There is no relevant literature to support the use of MRI in women <30 years of age with symptoms of pathologic nipple discharge. FDG-PET Breast Dedicated There is no relevant literature to support the use of FDG-PET in women <30 years of age with symptoms of pathologic nipple discharge. Image-guided Core Biopsy Breast There is no relevant literature to support the use of image-guided core biopsy in women <30 years of age with symptoms of pathologic nipple discharge. However, if an imaging abnormality is identified, US may be used to direct biopsy. Image-Guided Fine Needle Aspiration Breast There is no relevant literature to support the use of image-guided FNA in women <30 years of age with symptoms of pathologic nipple discharge. Sestamibi MBI There is no relevant literature to support the use of MBI in women <30 years of age with symptoms of pathologic nipple discharge.


Evaluation of Nipple Discharge

Evaluation of Nipple Discharge. Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise is assessing the symptomatic breast [35,36]. Ductography There is no relevant literature to support the use of ductography for evaluation of transgender patients with nipple discharge. MRI Breast There is no relevant literature to support the use of MRI for evaluation of transgender patients with nipple discharge. Evaluation of Nipple Discharge FDG-PET Breast Dedicated There is no relevant literature to support the use of FDG-PET for evaluation of transgender patients with nipple discharge. Image-guided Core Biopsy Breast There is no relevant literature to support the use of image-guided core biopsy for evaluation of transgender patients with nipple discharge. However, if an imaging abnormality is identified, US may be used to direct biopsy. Image-Guided Fine Needle Aspiration Breast There is no relevant literature to support the use of image-guided FNA for evaluation of transgender patients with nipple discharge. Sestamibi MBI There is no relevant literature to support the use of MBI for evaluation of transgender patients with nipple discharge. Digital Breast Tomosynthesis Diagnostic Although there is no relevant literature to support the use of DBT alone in assessing nipple discharge, mammography is useful for evaluating pathologic nipple discharge in male and female patients in this age group [30]. Early studies with DBT demonstrate promise is assessing the symptomatic breast [35,36]. Ductography There is no relevant literature to support the use of ductography for evaluation of transgender patients with nipple discharge. MRI Breast There is no relevant literature to support the use of MRI for evaluation of transgender patients with nipple discharge.


Assessment of Gravid Cervix

Assessment of Gravid Cervix.  In addition to CL screening for those at risk for PTB, other clinical scenarios may arise in which imaging assessment of the gravid cervix may be of interest. These include suspected preterm labor, induction of labor, and active term labor. Additional clinical scenarios, which may require a focused assessment of the gravid cervix, include suspected abnormal placentation including placenta previa, vasa previa, and lower uterine segment and/or cervical fibroids that may impede progression of labor and potential umbilical cord prolapse. 3-D Transvaginal US Three-dimensional TVUS acquires a volumetric data set that can be reformatted and analyzed in any plane. Three- dimensional TVUS may eventually be of benefit for certain clinical scenarios; however, there is currently insufficient data to recommend its routine use. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document. Reprint requests to: publications@acr.org Assessment of Gravid Cervix US Elastography Cervix US elastography is an imaging technique that assesses tissue stiffness. Although the available data suggest that US elastography may be beneficial in evaluating the gravid cervix [14-17], technical standards and normal reference values are lacking, and the technique remains investigational. As such, there is currently insufficient data to recommend its use in routine screening for PTB in low-risk and high-risk women, suspected preterm labor, and predicting successful induction of labor [18-22].


Assessment of Gravid Cervix

Assessment of Gravid Cervix. US Cervix Transperineal Transperineal US is an alternate approach to transvaginal evaluation of the gravid cervix and may be a complementary method to transabdominal US in certain clinical situations, such as large body habitus or when incomplete distention of the bladder limits transabdominal cervical assessment. The transperineal approach is superior to transabdominal US, although inadequate visualization of the cervix has been reported in up to 22% of patients [26]. An inability to adequately assess the cervix via the transperineal approach may result from shadowing from the symphysis pubis and rectal gas and stool. Adequate assessment by transperineal US is also dependent on sonographer experience. Transperineal assessment of the gravid cervix has been shown to be comparable to TVUS by several studies. Good correlation between CL measurements obtained transperineally and transvaginally have been reported in normal gravid cervix patients at each trimester, and the accuracy improves as the pregnancy progresses [27]. In a study by Hertzberg et al [28], similar levels of diagnostic confidence were achieved via the transperineal and transvaginal approaches, although there was a clear preference expressed by the interpreting physician for the latter. CLs were found to be comparable after 20 weeks gestational age, and CL measured between 14 and 20 weeks gestational age were statistically shorter via the transperineal approach. In a study of women between 22 and 24 weeks gestational age, Cicero et al [26] reported transperineal CL comparable to those obtained transvaginally. Standard second and third trimester transabdominal US evaluation may inadequately visualize the cervix or demonstrate findings suspicious for shortening. In such cases, transvaginal or transperineal US have been recommended for further evaluation [23].


Assessment of Gravid Cervix

Assessment of Gravid Cervix. If TVUS is declined by the patient or if the risk of TVUS is deemed too high (eg, placenta previa, suspected preterm premature rupture of membranes), transperineal US is a suitable alternative. If transperineal US is performed, the above caveats regarding CL in the early second trimester should be noted. US Cervix Transvaginal TVUS allows for the most complete assessment of the cervix, yet its use in universal screening of low-risk women remains controversial. Supportive evidence for universal screening comes from two studies evaluating the rates of PTB before and after implementation of a universal transvaginal cervical screening program [29,30]. Following implementation of their screening program, Son et al [29] demonstrated statistically significant decreases in the rates of spontaneous PTB <37 weeks (4.8% versus 4.0%), <34 weeks (1.3% versus 1.0%), and <32 weeks (0.7% versus 0.5%). Temming et al [30] demonstrated similar findings following implementation of their screening program; however, statistically significant decreases only were observed in the rates of spontaneous PTB <28 weeks (2.0% versus 0.7%) and <24 weeks (1.5% versus 0.35%). Other studies demonstrate no clear benefit to transvaginal screening, thereby calling into question its appropriateness. In one study evaluating a CL screening program in nulliparous women, no statistical difference was observed in the rate of spontaneous PTB in patients who underwent screening compared with those who did not [31]. In a separate study of nulliparous women, the predictive accuracy of serial TVUS for spontaneous PTB Although TVUS is not contraindicated in the setting of placenta previa, it should be performed using real-time imaging as the probe is advanced.


Assessment of Gravid Cervix

Assessment of Gravid Cervix. The safety in this setting is based on the presumption that the angle between the cervix and the vaginal probe is sufficient to prevent the probe from inadvertently slipping into the cervix and that real-time imaging is used throughout the procedure to assess the relationship between the probe tip and the cervix [33]. US Cervix Transperineal Transperineal US is an alternate approach to transvaginal evaluation of the gravid cervix and may be useful in certain clinical scenarios, such as large body habitus or when incomplete distention of the bladder limits the transabdominal cervical assessment. The transperineal approach is superior to transabdominal US, and transperineal assessment of the gravid cervix has been shown to be comparable to TVUS [27]. Good correlation between CL measurements obtained transperineally and transvaginally have been reported in normal gravid patients at each trimester [26-28]. In a study by Hertzberg et al [28], similar levels of diagnostic confidence were achieved with both transperineal and transvaginal approaches, noting a clear preference expressed for the latter. CL was found to be comparable after 20 weeks gestational age; however, CL measured between 14 and 20 weeks gestational age was statistically shorter via the transperineal approach. Given the apparent difference in accuracy of transperineal CL in the early second trimester, the authors suggested performing transvaginal imaging when short CL are obtained transperineally in the early second trimester. In a study of women between 22 and 24 weeks gestational age, Cicero et al [26] reported satisfactory transperineal visualization of the cervix in approximately 80% of cases. CLs obtained by the transperineal approach during this gestational age were also comparable to those obtained transvaginally. TVUS is the preferred approach for assessment of the gravid cervix in high-risk patients, but there may be instances in which TVUS is not possible because of patient discomfort or preference.


Assessment of Gravid Cervix

Assessment of Gravid Cervix. If TVUS is declined by the patient or if the risk of TVUS is deemed too high (eg, placenta previa, suspected preterm premature rupture of membranes), transperineal US is a suitable alternative. In such instances, transperineal US would be indicated, noting the above caveats regarding CL in the early second trimester. Assessment of Gravid Cervix US Cervix Transvaginal TVUS is the reference standard of imaging modalities used for assessment of the gravid cervix. The transvaginal approach affords the shortest distance between transducer and cervix, and TVUS transducers typically offer higher frequency evaluation and greater detailed evaluation. The combination of these features allows for complete visualization of the cervix, including the internal os where changes increasing the risk of PTB first occur. Lastly, transvaginal imaging is a highly reproducible test. Several studies have demonstrated that identification of a short CL by TVUS decreases the rate of PTB by directing patients to appropriate interventions. In a randomized placebo-controlled study by Fonseca et al [6], women with a sonographically short cervix who received progesterone demonstrated a 44% reduction in the rate of PTB <34 weeks, as well as a 41% decrease in neonatal morbidity. A separate randomized placebo-controlled study confirmed the benefit of progesterone administration and found a 45% decrease in PTB <33 weeks and a 50% decrease in PTB <28 weeks [8]. Reduction in PTB rates was also observed in patients undergoing cervical pessary placement [7]. When compared with patients undergoing expectant management, pessary placement was associated with a 78% reduction of PTB <34 weeks. Lastly, short CL treated by cerclage has been found to decrease PTB. In a meta- analysis of 5 trials of high-risk patients with short CL, cerclage placement resulted in a 30% decrease in PTB <35 weeks with significantly decreased rates of PTB seen before 37, 32, 28, and 24 weeks [5].


Assessment of Gravid Cervix

Assessment of Gravid Cervix. Given the availability of several effective interventions for the prevention of PTB, TVUS cervical screening for high-risk patients is recommended. Routine TVUS screening is also supported by the American College of Obstetricians and Gynecologists and Society for Maternal-Fetal Medicine [36,37]. Although TVUS is not contraindicated in the setting of placenta previa, it should be performed using real-time imaging as the probe is advanced. The safety in this setting is based on the presumption that the angle between the cervix and the vaginal probe is sufficient to prevent the probe from inadvertently slipping into the cervix and that real-time imaging is used throughout the procedure to assess the relationship between the probe tip and the cervix [33]. Cervical Cerclage Patients who have undergone history-indicated cerclage for cervical insufficiency represent a subset of high-risk patients. In these patients with a history of one or more second trimester losses, cerclage placement may be offered during the early second trimester. In one recent study screening cerclage patients by TVUS until 26 weeks, a shorter CL below the cerclage and cervical funneling were shown to be associated with a higher rate of PTB [38]. In a separate study evaluating postcerclage patients between 18 and 24 weeks, cervical funneling was the only variable independently associated with increased risk of PTB before 34 weeks [39]. Although these and other studies suggest that short CL and cervical funneling are associated with higher rates of PTB in patients with cerclage, the Society for Maternal-Fetal Medicine does not recommend routine surveillance for this subset of high-risk patients because there is insufficient data supporting a clinical benefit to screening [37].


Assessment of Gravid Cervix

Assessment of Gravid Cervix. If assessment of the cerclage is performed, additional measurements irrespective of approach (eg, transabdominal, transvaginal, or transperineal) may include the total length of closed cervix regardless of cerclage sutures, and if funneling is present, the length of closed cervix from the level of cervical funneling to the level of the cerclage sutures. Variant 3: Assessment of gravid cervix. Suspected preterm labor. Initial imaging. US Cervix Transabdominal To our knowledge, there is no relevant literature regarding the use of transabdominal US in the evaluation of the cervix for suspected preterm labor. US Cervix Transperineal Transperineal US is an alternate approach to transvaginal evaluation of the gravid cervix. In one study, adequate visualization of the cervix was achieved in 82% of patients in preterm labor with good agreement of transperineal and transvaginal measurements with an intraclass correlation coefficient of 0.83 [40]. The mean difference in cervical measurements between transperineal and transvaginal approaches was 1.5 mm, with transperineal US underestimating CL in most cases. No significant disagreement between both methods was observed above or below a length of 25 mm. A study by Dimassi et al [41] also reported a strong correlation in CL obtained by both methods as well as a low mean difference in cervical measurements (0.38 mm). TVUS would be preferred for assessment of the cervix in cases of suspected preterm labor. Nevertheless, transperineal US would be an adequate alternative in the event that TVUS is declined by the patient or if the risk of TVUS is deemed too high (eg, placenta previa, suspected preterm premature rupture of membranes). Assessment of Gravid Cervix US Cervix Transvaginal TVUS is the reference standard of imaging modalities used for assessment of the gravid cervix because it allows for complete visualization of the cervix, including the internal os where changes of PTB first occur. Transvaginal imaging is highly reproducible.


Assessment of Gravid Cervix

Assessment of Gravid Cervix. Taken together, the data demonstrate that although TVUS has limitations in its predictive ability in identifying those who will progress to PTB, its greatest value is its high negative predicative value. As such, transvaginal assessment of the gravid cervix would be the preferred approach in cases of suspected preterm labor. Although TVUS is not contraindicated in the setting of placenta previa, it should be performed using real-time imaging as the probe is advanced. The safety in this setting is based on the presumption that the angle between the cervix and the vaginal probe is sufficient to prevent the probe from inadvertently slipping into the cervix and that real-time imaging is used throughout the procedure to assess the relationship between the probe tip and the cervix [33]. Variant 4: Assessment of gravid cervix. Induction of labor or active term labor. Initial imaging. US Cervix Transabdominal To our knowledge, there is no relevant literature regarding the use of transabdominal US in the evaluation of the cervix prior to induction of labor or during active term labor. However, a meta-analysis of 31 studies demonstrated limited value in predicting the outcome of induced labor [49]. Studies that are more recent also report conflicting data. In one study, a shorter CL prior to induction was associated Although TVUS is not contraindicated in the setting of placenta previa, it should be performed using real-time imaging as the probe is advanced. The safety in this setting is based on the presumption that the angle between the cervix and the vaginal probe is sufficient to prevent the probe from inadvertently slipping into the cervix and that real-time imaging is used throughout the procedure to assess the relationship between the probe tip and the cervix [33]. Supporting Documents The evidence table, literature search, and appendix for this topic are available at https://acsearch. acr.org/list.


Major Blunt Trauma

Major Blunt Trauma.  Trauma is the leading cause of mortality for people in the United States who are <45 years of age, and it is the fourth leading cause of death overall [3]. Polytrauma can be defined as an injury to at least two body parts, including the head, neck, chest, abdomen, pelvis, and at least one extremity, with any one or a combination of these injuries being potentially fatal. MR urography (MRU) is also tailored to improve imaging of the urinary tract system. Unenhanced MRU relies upon heavily T2-weighted imaging of the intrinsic signal from urine for evaluation of the urinary tract. IV contrast is administered to provide additional information regarding obstruction, urothelial thickening, focal lesions, and stones. A contrast-enhanced T1-weighted series should include corticomedullary, nephrographic, and excretory Reprint requests to: publications@acr.org Major Blunt Trauma phase. Similar to CTU, hydration or low-dose furosemide can improve urinary tract distension and study quality. Thin slice acquisition and multiplanar imaging should be obtained. MRU is most commonly performed at 1.5T, but imaging at 3T has become more widely used; however, comparison of 3T MRU and CTU has not been published in the literature. Discussion of Procedures by Variant Variant 1: Major blunt trauma. Hemodynamically unstable. Initial imaging. CT Whole Body There is limited literature to support the use of WBCT in patients who are hemodynamically unstable [6,7]. Patients who remain hemodynamically unstable despite initial attempts at resuscitation and who have positive signs for abdominal trauma (eg, a positive FAST) should proceed directly to exploratory laparotomy, with CT imaging deferred until after operative intervention. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8].


Major Blunt Trauma

Major Blunt Trauma. US FAST Scan Chest Abdomen Pelvis The role of FAST (or extended-FAST or chest abdominal-FAST in evaluating chest injury) is primarily one of triage; a positive FAST and signs of hemodynamic instability may lead to immediate surgical intervention rather than CT [9,10]. Extended-FAST has been found to be effective in ruling out pneumothorax [11]. Although ultrasound (US) may be able to diagnose certain thoracic and abdominal injuries, its relatively lower specificity compared with CT does not make it a sufficient test to exclude injuries to these areas [5]. FAST has been found to have a high false-negative rate in patients with pelvic fractures [12]. Radiography Trauma Series Trauma series radiographs in the unstable patient typically consist of portable radiographs of the chest and pelvis. A portable anteroposterior (AP) chest radiograph helps screen for immediately life-threatening findings, such as tension pneumothorax and significant mediastinal injury, as well as confirms line placement [13]. A portable radiograph of the pelvis can evaluate for unstable pelvic injuries and hip dislocation [4]. MRI Abdomen and Pelvis There is no relevant literature to support the use of MRI in the initial evaluation of the unstable trauma patient. MRI is not performed because of the time required in the emergent setting. Variant 2: Major blunt trauma. Hemodynamically stable. Not otherwise specified. Initial imaging. CT Whole Body Currently, there is no practice consensus or validated decision rules for deciding which patients should receive WBCT versus selective CT imaging for blunt trauma. Some studies have found a survival benefit to WBCT compared with selective CT [14], whereas others have found no survival benefit [15]. Meta-analyses have yielded conflicting results with respect to improvements in mortality [16-18]. Therefore, clinical judgement remains vital for determining which patients should obtain WBCT versus selective CT.


Major Blunt Trauma

Major Blunt Trauma. Indications that may warrant WBCT imaging as defined above, include high-velocity (>35 mph) motor vehicle collision (MVC), MVC resulting in rollover or passenger ejection, motorcycle trauma, bicycle injury, MVC- pedestrian collision, and a fall from a height of >15 feet. Additional considerations include patient age and functional status, hemodynamic stability, neurological status, and results of initial imaging from portable radiographs of the chest and pelvis, and/or FAST. CT of the chest, abdomen, and pelvis with IV contrast has greater sensitivity for detecting visceral organ and vascular injury compared with noncontrast CT, and contrast-enhanced CT of these areas should be primarily considered unless absolutely contraindicated [19,20]. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8]. MRI Abdomen and Pelvis There is no relevant literature to support the initial use of MRI in patients who are hemodynamically stable, not otherwise specified. US FAST Scan Chest Abdomen Pelvis The role of FAST is primarily one of triage; a positive FAST and signs of hemodynamic instability may lead to immediate surgical intervention rather than CT. Although US may be able to diagnose certain thoracic and abdominal injuries, its relatively lower specificity compared with CT does not make it a sufficient test to fully exclude injuries to these areas [5]. Major Blunt Trauma Fluoroscopy Retrograde Urethrography There is no relevant literature to support the use of retrograde urethrography in patients with major blunt trauma who are hemodynamically stable, not otherwise specified. Refer to Variant 6 if there is suspicion of urinary tract injury. CT Whole Body The decision regarding which patients should receive WBCT versus selective CT imaging for blunt trauma will depend on factors beyond facial injury.


Major Blunt Trauma

Major Blunt Trauma. Some studies have found a survival benefit to WBCT compared with selective CT [14], whereas others have found no mortality benefit [15]. Meta-analyses have found conflicting results with respect to improvements in mortality [16-18]. Therefore, clinical judgement remains vital for determining which patients should obtain selective CT versus WBCT. Indications that may warrant WBCT imaging as defined above include high-velocity (>35 mph) MVC, MVC resulting in rollover or passenger ejection, motorcycle trauma, bicycle injury, MVC-pedestrian collision, and a fall from a height of >15 feet. Additional considerations include patient age and functional status, hemodynamic stability, neurological status, and results of initial imaging from portable radiographs of the chest and pelvis, and/or FAST. CT of the chest, abdomen, and pelvis with IV contrast has greater sensitivity for detecting visceral organ and vascular injury compared with noncontrast CT, and contrast-enhanced CT of these areas should be primarily considered unless absolutely contraindicated [19,20]. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8]. Radiography Trauma Series In the setting of blunt facial trauma, facial and cervical lateral radiographs may also be part of the initial trauma series radiographs, which also typically consists of portable radiographs of the chest and pelvis. Single cervical radiographs can rapidly evaluate for severe fracture, abnormal alignment, and prevertebral swelling, but it may miss nondisplaced fractures that are evident on CT. The portable AP chest radiograph helps screen for immediately life- threatening findings, such as tension pneumothorax and significant mediastinal injury, as well as confirms line placement [13]. A portable radiograph of the pelvis can evaluate for unstable pelvic injuries and hip dislocation [4]. Variant 4: Major blunt trauma. Hemodynamically stable. Suspected extremity trauma.


Major Blunt Trauma

Major Blunt Trauma. Initial imaging. The body regions covered in this clinical scenario are the upper extremity and lower extremity. CT Whole Body Currently, there is no practice consensus or validated decision rules for deciding which patients should receive WBCT versus selective CT imaging for blunt trauma, and extremity injuries alone will not determine which is Major Blunt Trauma appropriate. Some studies have found a survival benefit to WBCT compared with selective CT [14], whereas others have found no mortality benefit [15]. Meta-analyses have found conflicting results with respect to improvements in mortality [16-18]. Therefore, clinical judgement remains vital for determining which patients should obtain selective CT versus WBCT. Indications that may warrant WBCT imaging as defined above include high-velocity (>35 mph) MVC, MVC resulting in rollover or passenger ejection, motorcycle trauma, bicycle injury, MVC-pedestrian collision, and a fall from a height of >15 feet. Additional considerations include patient age and functional status, hemodynamic stability, neurological status, and results of initial imaging from portable radiographs of the chest and pelvis, and/or FAST. CT of the chest, abdomen, and pelvis with IV contrast has greater sensitivity for detecting visceral organ and vascular injury compared with noncontrast CT, and contrast-enhanced CT of these areas should be primarily considered unless absolutely contraindicated [19,20]. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8]. CT Extremity In certain cases, CT may be appropriate for fracture characterization, detection of radiographically occult fractures, or operative planning. CTA Extremity CT angiography (CTA) of an upper or lower extremity injury may also be considered and could be obtained during the same acquisition period to evaluate for extremity arterial injury when clinically suspected [24].


Major Blunt Trauma

Major Blunt Trauma. US FAST Scan Chest Abdomen Pelvis The role of FAST is primarily one of triage regardless of extremity injuries; a positive FAST and signs of hemodynamic instability may lead to immediate surgical intervention rather than CT. Although US may be able to diagnose certain thoracic and abdominal injuries, its relatively lower specificity compared with CT does not make it a sufficient test to exclude injuries to these areas [5]. Radiography Extremity Single-view radiographs of the traumatized extremity take little time and are frequently included in this setting. Radiography Trauma Series Trauma series radiographs typically consist of portable radiographs of the chest and pelvis and/or cross table cervical spine. A portable AP chest radiograph helps screen for immediate life-threatening findings, such as tension pneumothorax and significant mediastinal injury, as well as confirms line placement [13]. A portable radiograph of the pelvis can evaluate for unstable pelvic injuries and hip dislocation [4]. Radiographs of the suspected injured extremity are the first-line examination to be obtained. Variant 5: Major blunt trauma. Hemodynamically stable. Suspected bowel trauma. Initial imaging. CT Abdomen and Pelvis For blunt trauma, CT of the abdomen and pelvis with IV contrast is recommended, in the portal venous phase 70 seconds after contrast administration, for ideal characterization of solid organ injury. This may be obtained in conjunction with arterial phase images as well as delayed imaging of the abdomen and pelvis. The administration of oral contrast material has not been found to alter the sensitivity or specificity for blunt abdominal injuries and is not recommended because it can delay definitive diagnosis of other injuries [25]. Noncontrast CT of the abdomen and pelvis should ideally be avoided when possible because of its lower sensitivity for detecting both visceral organ and vascular injuries [19].


Major Blunt Trauma

Major Blunt Trauma. CT Whole Body Currently, there is no consensus for deciding which patients should receive WBCT versus selective CT imaging of the abdomen and pelvis for blunt trauma with concern for bowel injury. Some studies have found a survival benefit to WBCT compared with selective CT [14], whereas others have found no mortality benefit [15]. Meta-analyses have found conflicting results with respect to improvements in mortality [16-18]. Therefore, clinical judgement remains vital for determining which patients should obtain selective CT versus WBCT. Indications that may warrant WBCT imaging as defined above include high-velocity (>35 mph) MVC, MVC resulting in rollover or passenger ejection, motorcycle trauma, bicycle injury, MVC-pedestrian collision, and a fall from a height of >15 feet. Additional considerations include patient age and functional status, hemodynamic stability, neurological status, and results of initial imaging from portable radiographs of the chest and pelvis, and/or Major Blunt Trauma FAST. CT of the chest, abdomen, and pelvis with IV contrast has greater sensitivity for detecting visceral organ and vascular injury compared with noncontrast CT, and contrast-enhanced CT of these areas should be primarily considered unless absolutely contraindicated [19,20]. Patients who have an abnormal chest radiograph in the setting of trauma have clinically significant rates of major injury on CT chest [8] CTA Abdomen and Pelvis CT in the arterial phase may be carried through the abdomen and pelvis to assess for active arterial bleeding to abdominopelvic viscera and soft tissues. If 3-D reconstructions are included, then it is considered a CTA study to more closely evaluate the arterial structures for findings such as pseudoaneurysm. CTA of the abdomen has been shown to detect more splenic vascular injuries than that of CT of the abdomen in the portal venous phase alone [26].