Neurology_Adams

Neurology_Adams. Syphilitic myelitis is also discussed in Chap. 31. Bacterial abscess of the spinal cord is rare, especially in comparison to epidural spinal abscess, and it is recognized by MRI. At times, it stands as a single pyogenic metastasis from a distant infection and subsequent bacteremia, but more often there has been spread from a contiguous infected surgical site or a fistulous connection with a superficial paraspinal abscess. Vertebral osteomyelitis is addressed further on in relation to epidural abscess. Sarcoid Myelitis (See Also Sarcoidosis in Chap. 31)


Neurology_Adams

Neurology_Adams. Sarcoid granulomas may occur as one or more intramedullary spinal cord masses, as in the cases reported by Levivier and colleagues. In our experience, the granulomatous lesion, which may be focal or multifocal, simulates demyelinative disease with respect to its tendency to relapse and remit and in its response to corticosteroids. An asymmetrical ascending paraparesis and bladder disturbance have been the main features in our patients. Usually there is evidence of systemic sarcoidosis and the CSF is abnormal (increase in cells and protein; glucose usually normal), but we have encountered a few instances of sarcoid restricted to the spinal cord before it was evident in the mediastinum (i.e., thoracic CT failing to demonstrate hilar adenopathy or diffuse parenchymal lung disease). Elevation of the spinal fluid IgG concentration and oligoclonal bands may be found, but they are not consistent features; often there are activated histiocytes in the CSF.


Neurology_Adams

Neurology_Adams. The use of angiotensin-converting enzyme levels in the CSF to distinguish sarcoidosis from multiple sclerosis suffers from the lack of normative values for this test, but it is reported in some small series to be elevated in two-thirds of patients. The MRI is abnormal and the conus or other portions of the cord reveal intramedullary lesions. The most characteristic finding, however, is a multifocal-subpial nodular enhancement of the meninges adjacent to a lesion within the cord or nerve roots—a picture that resembles neoplastic meningeal infiltration. The diagnosis can be confirmed by mediastinal lymph node biopsy or by the far less desirable method of biopsy of the spinal meninges, spinal roots and affected subpial cord.


Neurology_Adams

Neurology_Adams. On occasion, a number of other rare granulomatous conditions cause an intrinsic or, more often, extrinsic compressive myelopathy; these, include brucellosis, xanthogranulomatosis, and eosinophilic granuloma. The diagnosis may be suspected if the systemic disease is apparent at the time but usually, only the histology of a surgical specimen reveals the underlying process.


Neurology_Adams

Neurology_Adams. This condition is worthy of emphasis because the diagnosis is often missed or mistaken for another disease, sometimes with disastrous results. Children or adults may be affected. Infection of the epidural space has a wide variety of sources. Staphylococcus aureus is the most frequent etiologic agent, equally distributed between methicillin resistant and methicillin sensitive types, followed in frequency by streptococci, gram-negative bacilli, and anaerobic organisms. An injury to the back, often trivial at the time, furunculosis or other skin or wound infection, or a bacteremia may permit seeding of the spinal epidural space or of a vertebral body. This gives rise to osteomyelitis with extension to the epidural space. Occasionally, the spread is from an infected disc. Diabetes and recently treated cancer may be risk factors. Another source is bacteremia following the use of nonsterile needles or the injection of contaminated drugs. The thoracic spine is the most frequently affected,


Neurology_Adams

Neurology_Adams. treated cancer may be risk factors. Another source is bacteremia following the use of nonsterile needles or the injection of contaminated drugs. The thoracic spine is the most frequently affected, perhaps simply because of its greater length compared to the other portions of the spine.


Neurology_Adams

Neurology_Adams. Organisms may be introduced into the epidural space during spinal surgery or rarely via a lumbar puncture needle during epidural or spinal anesthesia or from epidural injections of steroid or other therapeutic agents; the localization is then over the lumbar and sacral roots. In these cases of cauda equina epidural abscess, back pain may be severe but neurologic symptomatology is minimal unless the infection extends upward to the upper lumbar and thoracic segments of the spinal cord. It must be acknowledged that some, even fulminant, cases have no clear source in the body for the bacterial abscess but most of these instances occur in patients who are diabetic or have cancer, even if the latter has been adequately treated.


Neurology_Adams

Neurology_Adams. At first, the purulent process in the cervical or thoracic region is accompanied only by low-grade fever and aching local back pain, usually intense, in most cases followed within a day or several days by radicular pain. Headache and nuchal rigidity are sometimes present; more often there are just persistent pain and a disinclination to move the back. After several days, there may be a rapidly progressive paraparesis associated with sensory loss in the lower parts of the body and sphincteric paralysis. In some cases, the evolution of the myelopathy is more gradual. Examination discloses the signs of a complete or partial transverse cord lesion, including at times the elements of spinal shock if paralysis has evolved rapidly. Percussion of the spine usually elicits tenderness over the site of the infection.


Neurology_Adams

Neurology_Adams. A distinction is often made between this typical acute to subacute form of abscess and a more indolent type that is due to a partially granulomatous lesion over several segment of the spine. This form does not always require surgical treatment, as detailed below. Diagnosis The diagnosis can usually be ascertained from MRI (Fig. 42-2) but care must be taken to obtain images from levels rostral and caudal enough to detect the infected collection. There may be enhancement of the margins of the purulent collection after several days.


Neurology_Adams

Neurology_Adams. If an abscess is known to be present, lumbar puncture should not be performed, however, if the CSF space is inadvertently breached, the CSF usually contains white cells but of surprisingly small number (fewer than 100/mm3), both polymorphonuclear leukocytes and lymphocytes, unless of course, the needle penetrates the abscess, in which case pus is obtained. The CSF protein content is high, (100 to 400 mg/100 mL or more) but the glucose is normal. Elevation of the sedimentation rate, C-reactive protein, and peripheral neutrophilic leukocytosis are additional indicators to the diagnosis. The last of these tests is abnormal in two-thirds of cases. Blood cultures demonstrate the organism in a similar proportion. Cultures from the CSF are infrequently positive. The decades old series reported by Baker and colleagues is still a valuable reference, as is the more recent discussion by Darouiche. The differential diagnosis includes other forms of spinal cord compression and, in cases with


Neurology_Adams

Neurology_Adams. by Baker and colleagues is still a valuable reference, as is the more recent discussion by Darouiche. The differential diagnosis includes other forms of spinal cord compression and, in cases with areflexic spinal shock, tetraparesis and respiratory failure, Guillain-Barré syndrome.


Neurology_Adams

Neurology_Adams. Treatment The foregoing clinical findings and signs of am myelopathy call for MRI to be performed relatively quickly or CT myelography if MRI is not possible, to demonstrate the mass of the abscess and to determine its level as summarized by Ropper and Ropper. If not treated surgically by laminectomy and drainage before the onset of paralysis, the spinal cord lesion, which is probably partly a result of venous ischemia, becomes more or less irreversible. Broad-spectrum antibiotics in large doses must be given initially and the choice of treatment is then refined based on cultures from the abscess or the blood, or on a presumed source of bacteria, usually found to be staphylococcus.


Neurology_Adams

Neurology_Adams. When osteomyelitis of a vertebral body is the primary abnormality, the epidural extension may implicate only a few spinal sensory and motor roots, leaving long tracts and other intramedullary structures intact. In some cases with cervical epidural abscesses, stiff neck, fever, and deltoid-biceps weakness are the main neurologic abnormalities. Having emphasized the urgency of treatment, there are instances of small epidural abscesses that do not compress the cord and are limited to one or at most two levels for which we have avoided surgery by administering antibiotics alone. Also, lumbar epidural abscess and cauda equina compression without neurologic signs may be, in some cases, treated solely with antibiotics, although many surgeons favor drainage, which must be undertaken in any case, if osteomyelitis develops. Antibiotics are continued for several weeks, and the patient should be examined at regular intervals and have sequential MRI scans of the affected region.


Neurology_Adams

Neurology_Adams. Even after apparently successful drainage and antibiotic treatment of an epidural abscess, there may be a slowly progressive and then static syndrome of partial spinal cord compression. This is the result of formation of a fibrous and granulomatous reaction at the operative site. Distinguishing this sterile inflammatory mass from residual epidural abscess is quite difficult, even with enhanced MRI, but persistent fever, leukocytosis, and an elevated sedimentation rate, C-reactive and peripheral white blood cell count suggest that surgical drainage of the abscess was incomplete.


Neurology_Adams

Neurology_Adams. Spinal subdural abscess due to bacterial infections also occur and, clinically, are virtually indistinguishable from epidural ones on clinical grounds. The MRI will usually clarify the situation but a clue is provided by the CT myelogram, in which the subdural lesion has a less sharp margin and usually, a greater vertical extent. The epidural and subdural infections, if they smolder owing to delayed diagnosis or inadequate therapy, may also evolve into a local chronic adhesive meningomyelitis. Subacute pyogenic infections and granulomatous infections (tuberculous, fungal) may also arise in the spinal epidural space, as noted further on.


Neurology_Adams

Neurology_Adams. This process is presented in juxtaposition to epidural abscess, with which it is closely aligned. As with other forms of osteomyelitis, vertebral infection is typically due to hematogenous implantation of bacteria during episodes of bacteremia or, it is associated with the exogenous introduction of bacteria during spinal surgery, particularly if catheters or other devices, including for spinal stabilization, are incorporated. In the case of postsurgical infection, coagulase-negative staphylococci or propionibacterium are almost always implicated, whereas with bacteremia, a number of low-virulence organisms including staphylococcus are found and multiple organisms may be involved. The source of bacteremia may be urinary infection, endocarditis, or intravenous drug abuse but many affected individuals also have diabetes, are immunosuppressed, have cancer, or are receiving dialysis for renal failure. In the group of immunocompromised patients, unusual or endemic organisms such as Brucella


Neurology_Adams

Neurology_Adams. also have diabetes, are immunosuppressed, have cancer, or are receiving dialysis for renal failure. In the group of immunocompromised patients, unusual or endemic organisms such as Brucella may be found. However, in almost half of patients who have not had surgery, no source is identified. Approximately one-fifth of cases have an associated epidural abscess, as discussed above. This is often indicated by an increase in local back pain or extremely severe pain from the onset.


Neurology_Adams

Neurology_Adams. The lumbar spine is the region most affected (in contrast to the frequent thoracic distribution of epidural abscess). The typical presentation is relatively nondescript with back pain, elevated white blood cell count and C-reactive protein level. Fever, however, is inconsistent. Several types of imaging studies may be used to demonstrate the infection, however, MRI more dependably than CT shows edema within the bone marrow and, if there is destruction of the disc adjacent to an effective vertebral body, infection is almost certain. Technetium bone scans were popular for the demonstration of osteomyelitis in general but the findings may be nonspecific. A well-known adage is that neoplasms affecting the vertebral body do not cross the disc space whereas infections do so.


Neurology_Adams

Neurology_Adams. A point of contention has been the need for biopsy of the affected bone when blood cultures are negative and no obvious source of infection in the body can be found. This procedure is generally suggested although extension of the infection from the vertebral body to the paravertebral or epidural spaces may also be performed under CT guidance.


Neurology_Adams

Neurology_Adams. Initiating therapy with oral fluoroquinolones, with or without rifampin, has been suggested as a broad approach while the specific infecting bacteria are identified. Therapy is generally continued for at least 4 to 6 weeks, if not longer but no clear guidance is available on the appropriate duration. Surgical removal of infected bone is generally not undertaken unless the osteomyelitis is the result of implanted hardware during previous spinal surgery. Almost invariably, this hardware must be removed. Surveillance for persistent infection after treatment is probably appropriate but the MRI has not proven useful for this purpose. Inflammatory markers in the blood are apparently more dependable. A thorough review of this subject can be found in the clinical practice article by Zimmerli.


Neurology_Adams

Neurology_Adams. Purulent collections within the substance of the cord was first described by Hart in 1830 and, although it is rare, 73 cases had been reported by 1994 (Candon and Frerebeau). In some instances, the patient was known to have had systemic bacterial infection, septicemia, or endocarditis; in others, there was a contiguous abscess in the skin or subcutaneous tissues with a fistula to the spinal cord through an intervertebral foramen. Spinal cord abscess is a rare complication of spinal dysraphism or of a developmentally open dorsal fistulous tract. The symptoms are indistinguishable from those of epidural abscess, namely, spinal and radicular pain followed by sensory and motor paralysis; the CSF findings are also the same. Woltman and Adson described a patient in whom surgical drainage of an encapsulated intramedullary abscess led to recovery, and Morrison and associates reported a similar case caused by Listeria monocytogenes, which was successfully drained and the meningeal infection


Neurology_Adams

Neurology_Adams. encapsulated intramedullary abscess led to recovery, and Morrison and associates reported a similar case caused by Listeria monocytogenes, which was successfully drained and the meningeal infection suppressed by ampicillin and chloramphenicol. There was no way to be certain of the diagnosis prior to the availability of MRI.


Neurology_Adams

Neurology_Adams. Tuberculous osteomyelitis of the spine with kyphosis (Pott disease) is well known in regions of endemic tuberculosis. Children and young adults are most often affected. The osteomyelitis is the result of reactivation of tuberculosis at a site previously established by hematogenous spread. An infectious endarteritis causes bone necrosis and collapse of a thoracic or upper lumbar (less often cervical) vertebral body resulting in a characteristic angulated kyphotic deformity (Fig. 42-3); any degree of additional rotary instability allows the emergence of a gibbus deformity. Most patients have some active tuberculous infection as evidenced by fever, night sweats, and other constitutional symptoms; the sedimentation rate is invariably elevated but the degree may be slight. A compressive myelopathy occurs in some cases as a result of the spinal deformity, but it is infrequent and an epidural tuberculous abscess is a more common cause of cord compression (see below). What is surprising to us


Neurology_Adams

Neurology_Adams. occurs in some cases as a result of the spinal deformity, but it is infrequent and an epidural tuberculous abscess is a more common cause of cord compression (see below). What is surprising to us about Pott disease is the excellent result that may be obtained by external stabilization of the spine and long-term antituberculous medication. A recent young patient of ours was saved from an operation by the intercession by telephone of his father, a physician from India. Although there is some controversy regarding spinal surgery, it is certainly required in the presence of severe deformities or a compressive myelopathy as noted in Chap. 31.


Neurology_Adams

Neurology_Adams. Solitary tuberculoma of the spinal cord as part of a generalized infection is a rarity. More often, pus or caseous granulation tissue extrudes from an infected vertebra and gives rise to an epidural compression of the cord (Pott paraplegia, as distinct from Pott disease). Occasionally tuberculous meningitis may result in pial arteritis and spinal cord infarction. The paraplegia may appear before the tuberculous meningitis is diagnosed. All these forms of tuberculosis are infrequent in the United States and Western Europe, but we see a new case every several years in a patient who had spent his earlier life in India or Africa. Additional comments can be found in Chap. 31.


Neurology_Adams

Neurology_Adams. A wide variety of fungal and parasitic agents may involve the spinal meninges. Such infections are rare, and some do not occur at all in the United States or are limited to certain geographic areas, particularly among immigrant populations. Actinomyces, Blastomyces, Coccidioides, and Aspergillus may invade the spinal epidural space via intervertebral foramina or by extension from a vertebral osteomyelitic focus. Cryptococcus, which causes meningoencephalitis and, rarely, a cerebral granuloma, in our experience, seldom causes spinal lesions. Hematogenous metastases to the spinal cord or meninges may occur in both blastomycosis and coccidioidomycosis. Occasionally an echinococcal infection of the posterior mediastinum may extend to the spinal canal (epidural space) via intervertebral foramina and compress the spinal cord.


Neurology_Adams

Neurology_Adams. Schistosomiasis (bilharziasis) is a recognized cause of myelitis in the Asia, Africa, and South America. The spinal cord is a target for all three common forms of Schistosoma: S. haematobium, S. japonicum, and S. mansoni, but most particularly the last of these (see “Schistosomiasis” in


Neurology_Adams

Neurology_Adams. Chap. 31). The schistosomal ova evoke an intense granulomatous myelomeningoradiculitis. The lesions are destructive of gray and white matter, with ova in arteries and veins leading to vascular obstruction and ischemia (Scrimgeour and Gajdusek). Less often, a localized granuloma gives rise to a cord syndrome and, rarely, the disease takes the form of an acute transverse myelitis with massive necrosis of cord tissue (Queiroz et al). A pruritic “swimmer’s itch” at the site of entry of the parasite is reported by many patients in the days prior to the myelopathy. In the often cited review by Scrimgeour and Gajdusek, the latency between exposure and symptoms was 38 days to several years. We have cared for several patients over the years in whom the spinal cord in the low thoracic and lumbar region was infected approximately 3 weeks after they swam in contaminated water during an east African vacation and then returned home to the United States The CSF showed only a slight elevation of


Neurology_Adams

Neurology_Adams. region was infected approximately 3 weeks after they swam in contaminated water during an east African vacation and then returned home to the United States The CSF showed only a slight elevation of protein, but in almost all cases there is a pronounced pleocytosis ranging from 5 to 500 lymphocytes/mm3 and the glucose is normal or minimally reduced. Systemic and CSF eosinophilia are variable so are not dependable for diagnosis. The diagnosis is confirmed by the finding of elevated titers of antibody directed against the schistosome in the CSF or blood. There are usually oligoclonal bands of IgG in the CSF as well. The parasite can sometimes be found in biopsies of the rectosigmoid mucosa. The administration of praziquantel arrested the course of the illness, but all but one of our patients was left disabled.


Neurology_Adams

Neurology_Adams. Noninfectious Inflammatory Myelitis (Multiple Sclerosis and Acute and Subacute Transverse Myelitis) (See Chap. 35)


Neurology_Adams

Neurology_Adams. The spinal cord disorders that make up this category take the form of a leukomyelitis based on either demyelination or necrosis of portions of the spinal cord. The critical factor in their pathogenesis appears to be a disordered immune response, in some cases, as a response to an infection, and in others such as multiple sclerosis an idiopathic immune disorder. Varied clinical syndromes are produced, and the basic disease is classified in textbooks under headings such as acute transverse myelitis, postinfectious myelitis, postvaccinal myelitis, acute MS, neuromyelitis optica, and necrotizing myelitis. While each of these conditions may affect other parts of the nervous system (most often the optic nerves and brain), often the only manifestations are spinal. The aforementioned myelopathies are characterized by various degrees of inflammatory destruction, usually with lymphocytes congregating around venules in the cord, but they are sufficiently distinct to justify their separate


Neurology_Adams

Neurology_Adams. are characterized by various degrees of inflammatory destruction, usually with lymphocytes congregating around venules in the cord, but they are sufficiently distinct to justify their separate classification. Nonetheless, transitional cases sharing the clinical and pathologic attributes of more than one disease are encountered in any large clinical practice and pathologic collection. The subjects of multiple sclerosis, neuromyelitis optica and other primarily inflammatory myelitidies are also discussed in Chap. 35. Some of the main points are recapitulated here.


Neurology_Adams

Neurology_Adams. Postinfectious and Postvaccinal Myelitides (See Also Chap. 35) The characteristic features of these diseases are their temporal relationship following a viral infection or vaccination with the delayed development of neurologic signs over the period of a few days, and a monophasic course, that is, a single attack with variable degrees of recovery and no recurrence. These processes may involve the brain as well as the spinal cord, in which case the process is properly designated as acute disseminated encephalomyelitis (ADEM). On the basis of the clinical features of disseminated postinfectious encephalomyelitis and the animal model of experimental allergic encephalomyelitis (EAE), postinfectious myelitis is presumed to be immunologic in nature, reflecting an attack that is more or less confined to spinal cord myelin as described in more detail in Chap. 35.


Neurology_Adams

Neurology_Adams. The usual history in these cases is of weakness and numbness of the feet and legs (less often of the hands and arms), which typically develop over a few days, and for the sensory symptoms to ascend from the feet to the trunk. Paresthesias in the feet and legs, which simulate a polyneuropathy, are common early symptoms. Sphincteric disturbances and backache are also common in the first days but as often arise later. A slight asymmetry of the symptoms and signs, a sensory level on the trunk, or a Babinski sign clearly marks the disease as a myelopathy and serves to distinguish it from a rapidly progressive polyneuropathy such as the Guillain-Barré syndrome. Back pain of varying degree and headache and stiff neck may or may not be present. In about half of cases the patient can identify a recent infectious illness, usually a mundane upper respiratory syndrome, but the fever has usually abated when the neurologic symptoms begin. The illness evolves over several days, sometimes a single


Neurology_Adams

Neurology_Adams. recent infectious illness, usually a mundane upper respiratory syndrome, but the fever has usually abated when the neurologic symptoms begin. The illness evolves over several days, sometimes a single day or on the other extreme, over 1 or 2 weeks. Despite the term transverse myelitis, fewer than half of cases demonstrate a truly “transverse” involvement of the cord; more often there is an incomplete corticospinal and spinothalamic syndrome affecting one side more than the other. As discussed further on, it is usually not possible to distinguish an acute episode of postinfectious myelitis from the first attack of multiple sclerosis, but a well-defined preceding infection with certain organisms favors the former process. The latency between infection and myelitis is an uncertain matter but there are well-documented instances in which the febrile episode blends into the neurologic syndrome and others in which the latency has been 2 weeks; considerably longer intervals make the


Neurology_Adams

Neurology_Adams. but there are well-documented instances in which the febrile episode blends into the neurologic syndrome and others in which the latency has been 2 weeks; considerably longer intervals make the association suspect.


Neurology_Adams

Neurology_Adams. Almost invariably, the CSF contains lymphocytes and other mononuclear cells in the range of 10 to 50/mm3 (sometimes higher), with slightly raised protein and normal glucose content. However, there may be only 3 or 4 cells/mm3, or none, making the inflammatory aspect less clear. Oligoclonal bands are usually absent. In most instances that have come under our care, the MRI has shown slight T2 signal abnormalities and minimal gadolinium enhancement extending over 2 or 3 spinal segments. Although the cord may be swollen in these regions (Fig. 42-4), several of our patients with mild and partial myelitis have had normal MRI studies.


Neurology_Adams

Neurology_Adams. Clinical variants of this syndrome are frequent in our experience, including an almost pure paresthetic illness with posterior column dysfunction and the converse; a symmetrical paraparesis with analgesia below a level on the trunk but without involvement of deep sensation (a syndrome more typically associated with infarction in the territory of the anterior spinal artery); a syndrome of variable sensory loss involving the leg and groin on one side or both; a purely lumbosacral or sacral myelopathy (conus syndrome with saddle analgesia and sphincter disturbances); and a partial Brown-Séquard syndrome.


Neurology_Adams

Neurology_Adams. In the past, postinfectious myelitis was most often observed in relation to the common exanthems (rubella, rubeola, varicella). The neurologic signs appeared as the rash was fading, often with a slight recrudescence of fever. Practically all human viruses have at one time or another been found to have preceded acute myelitis; however, the DNA viruses such as Epstein-Barr and cytomegalovirus are most common, and hepatitis B, varicella, and enteroand rhinoviruses have been detected from time to time. Mycoplasma is almost unique in being a bacterial trigger of the disease, but as noted earlier, there is some uncertainty regarding its ability to cause direct infection rather than a postinfectious immune reaction. Our interpretation of the existing information still favors a postinfectious etiology. In most instances of postinfectious myelitis, the connection to a preceding infection is presumed but cannot be proved. Only the associations with EBV, CMV, and Mycoplasma seem fairly certain


Neurology_Adams

Neurology_Adams. In most instances of postinfectious myelitis, the connection to a preceding infection is presumed but cannot be proved. Only the associations with EBV, CMV, and Mycoplasma seem fairly certain based on the regularity of their occurrence, but it may simply reflect the relative ease with which a recent infection can be documented by serologic tests. The list of antecedent infections is otherwise much the same as for the Guillain-Barré syndrome with the notable difference of Campylobacter jejuni, which has not led to myelitis and is a frequent precedent to acute polyneuropathy. It can be reasonably assumed that, for example, pharyngitis, respiratory infection, and conjunctivitis, with or without fever, was a likely trigger for myelitis and the finding of abnormal liver function tests or severe pharyngitis with cervical adenopathy usually indicates EBV or, less often, CMV infection.


Neurology_Adams

Neurology_Adams. More difficult to understand are the large number of cases of myelitis, including autopsy-proven ones, in which the disease develops without an apparent antecedent infection. There is understandable uncertainty in such cases as to whether the illness is the opening phase of multiple sclerosis of the type described below under “Acute Demyelinating Myelitis of Multiple Sclerosis.” In the numerous cases of transverse myelitis under our care, fewer than half have shown other signs of MS after 10 to 20 years (this is a far lower incidence than disseminated multiple sclerosis following a bout of optic neuritis). There is also an isolated form of relapsing myelitis, sometimes but not always triggered by an infection that does not manifest lesions elsewhere in the neuraxis and therefore has an ambiguous relationship to MS. Further discussion of acute transverse myelitis in relation to other demyelinating diseases can be found below and in Chap. 35.


Neurology_Adams

Neurology_Adams. The pathologic changes in postinfectious myelitis take the form of numerous subpial and perivenular zones of demyelination, with perivascular and meningeal infiltrations of lymphocytes and other mononuclear cells, and para-adventitial pleomorphic histiocytes and microglia. Taken in isolation, these pathologic changes cannot be distinguished from those of MS. Treatment Once symptoms begin, it is not clear if any treatment is of consistent value. One’s first impulse, assuming the mechanism to be autoimmune, is to administer high doses of corticosteroids, a practice we have followed but without conviction. Perhaps it is advisable to do so, but there is as yet no evidence that this alters the course of the illness. We have also used plasma exchange or intravenous immune globulin in several patients with uncertain results, although this approach was seemingly helpful in a few patients who had an explosive clinical onset.


Neurology_Adams

Neurology_Adams. The prognosis of this illness is better than the initial symptoms might suggest. Invariably, the myelitic disease improves, sometimes to a surprising degree, but there are examples in which the sequelae have been severe and permanent. Pain in the midthoracic region or an abrupt, severe onset usually indicates a poor prognosis (Ropper and Poskanzer). The authors have several times given a good prognosis for long-term recovery and assurance that no relapse will occur, only to witness a recrudescence of other symptoms at a later date, indicating that the original illness was probably multiple sclerosis. Acute Demyelinating Myelitis of Multiple Sclerosis (Chap. 35)


Neurology_Adams

Neurology_Adams. Acute Demyelinating Myelitis of Multiple Sclerosis (Chap. 35) The lesions of acute MS share many of the features of the postinfectious type as noted above. However, the clinical manifestations of the former tend to evolve more slowly, over a period of 1 to 3 weeks or even longer. Also, a relation to antecedent infections is not often seen in MS. Only the occurrence of subsequent attacks or additional lesions revealed by MRI or evoked potentials indicates that the basic illness is one of chronic recurrent demyelination.


Neurology_Adams

Neurology_Adams. The most typical of clinical expression of demyelinating myelitis is with numbness that spreads over one or both sides of the body from the sacral segments to the feet, anterior thighs, and up over the trunk, with coincident but variable and usually asymmetric weakness and then paralysis of the legs. As this process becomes complete, the bladder is also affected. The sensorimotor disturbance may extend to involve the arms, and a sensory level can be demonstrated on the upper parts of the trunk. The CSF may show a mild lymphocytosis, as in the postinfectious variety, but it is as often normal. Oligoclonal bands may be absent with the first attack. Bakshi and colleagues have suggested that in myelitis as a result of MS, the changes seen on MRI occupy only a few adjacent spinal segments in comparison to the postinfectious lesions, which have a longer vertical extent, but this has not been a consistent distinction in our experience. As a general rule, acute spinal MS is relatively


Neurology_Adams

Neurology_Adams. in comparison to the postinfectious lesions, which have a longer vertical extent, but this has not been a consistent distinction in our experience. As a general rule, acute spinal MS is relatively painless and without fever, and the patient usually improves, with variable residual signs. The differential diagnosis of demyelinating myelitis is considered more fully in Chap. 35.


Neurology_Adams

Neurology_Adams. Treatment Corticosteroids, as outlined for the treatment of MS in Chap. 35, may lead to a regression of symptoms, sometimes with relapse when the medication is discontinued (after 1 to 2 weeks). Other patients, however, show no apparent response, and a proportion of cases have even continued to worsen while the medication was being given. Plasma exchange and intravenous immune globulin have reportedly been beneficial in individual cases, particularly in those with an explosive onset (see later). The results in our patients have been too variable to interpret. Neuromyelitis Optica, Acute and Subacute Necrotizing Myelitis, and Devic Disease (See Discussion in Chap. 35)


Neurology_Adams

Neurology_Adams. In every large center, examples of this disorder are found among the many patients who present with a subacute paraplegia or quadriplegia, sensory loss, and sphincter paralysis. The neurologic signs may erupt so precipitously that a vascular lesion is assumed. In most other cases, the disease evolves at a slower and usually stepwise pace, over several months or years. Necrotizing myelopathy is distinguished from the more common types of transverse myelitis by a persistent and profound flaccidity of the legs (or arms if the lesion is cervical), areflexia, and atonicity of the bladder—all reflecting a widespread necrosis that involves both the gray and white matter of the spinal cord over a considerable vertical extent. This clinical picture is unexpected for a spinal cord lesion and, therefore, is often mistakenly attributed to spinal shock or to a completely different process such as Guillain-Barré syndrome.


Neurology_Adams

Neurology_Adams. This combination of spinal cord necrosis and optic neuritis corresponds to the syndrome described by Devic in 1894 and named by him neuromyelitis optica (Devic disease). Nearly all neurologists agree that a similar clinical syndrome involving the optic nerve and spinal cord (usually without necrosis) may also be caused by postinfectious encephalomyelitis or by MS, however, the finding by Lennon and colleagues of a specific serum IgG antibody in half of cases of Devic disease was a notable advance. The antibody is directed against the aquaporin channel in capillaries of the cord, brainstem and cerebellum and its role in the pathogenesis of the disease partially resolves the decades old uncertainty regarding a distinction between Devic disease and forms of multiple sclerosis, in which the antibody is not present.


Neurology_Adams

Neurology_Adams. In both the isolated necrotic myelopathy and in Devic disease, a few or up to several hundred mononuclear cells per cubic millimeter and increased protein may be found in the CSF but oligoclonal banding is usually absent. Some cases show only an elevated protein concentration. More so than with postinfectious transverse myelitis, the MRI reveals extensive signal changes and gadolinium enhancement, usually occupying several contiguous spinal segments; called a longitudinally extensive lesion (Fig. 42-5). Imaging studies performed weeks or more after the onset of symptoms show atrophy of the involved segments of cord. Persistent swelling of the affected region is more suggestive of spinal cord tumor or another type of inflammation, but the permissible duration of cord swelling may extend for weeks. The electromyogram (EMG) often shows denervation of several contiguous myotomes, reflecting damage to the gray matter of those segments.


Neurology_Adams

Neurology_Adams. In cases coming to postmortem examination at variable times after the onset of symptoms, the lesion has proved to be a necrotizing myelitis with widespread loss of spinal cord tissue. The pattern of tissue destruction appears, at least in part, infarctive, that is, not respecting the borders of gray and white matter. However, areas of residual inflammation and demyelination are often detected at the edges of the destructive lesions. Older lesions leave the spinal cord cavitated or collapsed over a vertical extent of 5 to 20 cm, with conical extensions of necrosis into the gray matter above and below the area of transverse damage. Probably many of these cases would now be categorized as part of the neuromyelitis family with aquaporin autoantibodies.


Neurology_Adams

Neurology_Adams. Under the title “Subacute Necrotic Myelitis,” Foix and Alajouanine, and later Greenfield and Turner, and subsequently, Hughes, described a disorder mainly of adult men characterized by amyotrophic paraplegia that ran a progressive course over several months. The defining feature, one that still gives rise to lively polemical discussions, is severe necrosis of both gray and white matter in the lumbosacral region and a marked increase in the number of small vessels, their walls thickened, cellular, and fibrotic (“angiodysplastic”), yet without vascular occlusion. The veins are also thickened and surrounded by lymphocytes, mononuclear cells, and macrophages. As such, the disorder could be included under the vascular myelopathies discussed in the next section.


Neurology_Adams

Neurology_Adams. These findings have been difficult to interpret and their relationship to the group of arteriovenous malformations and fistulas, discussed later, has been unclear but we are inclined to the view of Antoni and others who were impressed with the prominence of large arteries and veins and have reinterpreted this pathologic process as an arteriovenous malformation. In many other cases of necrotic myelopathy that are not associated with a true vascular malformation, the vascular changes simply reflect a neovascular response to necrosis or may be examples of neuromyelitis optica.


Neurology_Adams

Neurology_Adams. A similar syndrome is produced by a rare idiopathic necrotizing vasculitis that is confined to the spinal cord (Caccamo et al). In these cases, there is a persistent and marked pleocytosis and some clinical stabilization with corticosteroids. One of our young male patients with this type of subacute necrotizing myelitis, responsive to corticosteroids, had mononuclear cells in the spinal fluid persistently over a year and died as a result of fulminant inflammatory cerebral hemorrhages. There were multiple occlusions of small vessels surrounding the spinal cord and a vasculitis. Polyarteritis nodosa and necrotizing arteritis only rarely involve the spinal cord. Schistosomiasis, as mentioned earlier, may also produce a necrotizing myelitis of the lumbosacral region.


Neurology_Adams

Neurology_Adams. This is an interesting and varied group of spinal cord disorders that are thought to be inflammatory but their nature has not been fully elucidated to our satisfaction in part because of a paucity of pathologic material. An inflammatory vasculopathy has been implicated, similar to what is imputed for cerebral lesions, but there may be areas of noninflammatory and nonvasculitic demyelination that simulate multiple sclerosis. The imaging features and response to treatment are likewise varied.


Neurology_Adams

Neurology_Adams. A rapidly evolving or subacute myelopathy occurs in association with systemic lupus erythematosus. As mentioned, the process is presumed to arise from a microvasculitis or an autoantibody. Propper and Bucknall presented such a case and reviewed 44 others in which patients with lupus developed a transverse myelitis over a period of days. There was back pain at the level of sensory loss (the cases we have seen have been painless), and pleocytosis and elevation of CSF protein. The MRI revealed segmental swelling of the spinal cord. Postmortem examinations have disclosed widespread vasculopathy of small vessels with variable inflammation and myelomalacia, and, rarely, a vacuolar myelopathy. Whether demyelination (so-called lupoid sclerosis due to an antibody reaction) can occur independently of a vasculopathy has not been clear to the authors.


Neurology_Adams

Neurology_Adams. Some but not all cases also have circulating antiphospholipid antibody; the relationship of these antibodies to the myelopathy and to microvascular occlusion is uncertain (see also “Antiphospholipid Antibody Syndrome” in Chap. 33 and further discussion in Chap. 35). The incidence of lupus myelopathy is not known; it must be rare but one such case is admitted to our service, in a hospital with an active rheumatology division, about every year.


Neurology_Adams

Neurology_Adams. In addition to a well-described posterior root ganglionopathy and sensory neuritis, an inflammatory myelitis is associated with Sjögren syndrome. In most instances, the patient has had overt symptoms of Sjögren disease including, the sicca complex, and in others, the association has been established through serologic testing or by the finding of inflammatory infiltration of minor salivary glands (obtained by biopsy). In many reported cases, the myelopathy has simulated the myelitis of MS, even to the extent of including episodes of optic neuritis as in the cases described by Williams and colleagues and by de Seze and coworkers. The myelitis has been in different cases acute, chronic, or relapsing and displayed MRI changes in the cord that would otherwise be considered to be postinfectious or demyelinating myelitis. The spinal fluid formula has also varied but generally does not contain oligoclonal bands. Treatment with prednisone and cyclophosphamide or methotrexate has been suggested


Neurology_Adams

Neurology_Adams. or demyelinating myelitis. The spinal fluid formula has also varied but generally does not contain oligoclonal bands. Treatment with prednisone and cyclophosphamide or methotrexate has been suggested and was seemingly successful in several of our patients.


Neurology_Adams

Neurology_Adams. A review of Sjögren myelopathy and peripheral neuropathy has been given by one of the authors with Berkowitz. There is little pathologic material on which to judge the association, but the presence of other inflammatory lesions of the central and peripheral nervous system in Sjögren disease makes the existence of myelitis plausible. Antibody tests (anti-SS-A [Ro] and SS-B [La]) and possibly a biopsy of the minor salivary glands (at the junction of mucosa and epidermis of the lower lip) are justified in patients with unusual myelopathies or in those with sicca symptoms; however, screening in this manner of all cases that otherwise suggest MS or postinfectious myelitis may be excessive. This subject is also reviewed in Chap. 35, in relation to multiple sclerosis.


Neurology_Adams

Neurology_Adams. There is also the rare occurrence of nondescript myelitis with scleroderma as mentioned above (systemic sclerosis). There it is emphasized that many cases are of the longitudinally extensive type. The authors of most reports acknowledge the difficulty in distinguishing between the myelopathies of various connective tissue diseases. There may be some response to corticosteroids and other immunosuppressive medications. Myopathy and neuropathy, particularly trigeminal neuritis, are more common manifestations of scleroderma. Behçet Disease Myelopathy (See Also Chap. 33)


Neurology_Adams

Neurology_Adams. Behçet Disease Myelopathy (See Also Chap. 33) This vascular and inflammatory disease is usually considered in the context of cerebral venous thrombosis and other forms of stroke but, in addition to the typical findings of orogenital ulcers and uveitis, it has varied manifestations in the nervous system in about 5 percent of cases (neuro-Behçet’s syndrome). Among these is a myelopathy that may relapse like MS and may occur at single or multiple sites in the cord or simulate neuromyelitis optica in causing a longitudinally extensive lesion. The lesions may take up gadolinium on MRI and a peculiar imaging “bagel sign” has been described by Uygunoglu and colleagues, consisting of central hypointense area with a hyperintense rim. The clinical syndrome and imaging changes are said to resolve with glucocorticoids. Paraneoplastic Myelitis (See Also Chap. 30)


Neurology_Adams

Neurology_Adams. Paraneoplastic Myelitis (See Also Chap. 30) A subacute necrotic myelitis developing in conjunction with bronchogenic carcinoma was first brought to notice by Mancall and Rosales in 1964. Several dozen cases have since been recorded in association with lymphomas and carcinomas, but the disease must be rare. Actually, in cancer patients, intramedullary metastasis, quite infrequent to begin with, is more common as a cause of intrinsic myelopathy and, of course, a compressive lesion is far more frequent than either of these conditions.


Neurology_Adams

Neurology_Adams. The clinical syndrome consists of a progressive painless loss of motor and then sensory function, usually with sphincter disorder, over weeks. Imaging studies demonstrate an area of T2 signal change in the cord, occupying one or several contiguous segments, similar to neuromyelitis optica (Devic disease); some have slight enhancement with gadolinium or rarely, imaging may be normal. This is in distinction to the nodular enhancing appearance of an intramedullary metastasis or of extradural metastatic disease with cord compression.


Neurology_Adams

Neurology_Adams. The CSF may contain a few mononuclear cells and a slightly increased protein, or it may be normal. The lesions are essentially of necrotic type and respect neither gray nor white matter, but the latter is more affected. There is little or no evidence of an infective-inflammatory or ischemic lesion, for the blood vessels, apart from a modest cuffing with mononuclear cells are normal. No tumor cells are visible in the CSF, meninges, or spinal cord tissue, and no virus has been isolated. Unlike the situation in most of the paraneoplastic neurologic disorders, there are no diagnostic markers by way of specific antineural antibodies. In particular, this myelopathy does not seem to be a component of the anti-Hu–associated encephalitis-neuropathy spectrum.


Neurology_Adams

Neurology_Adams. In some cases of paraneoplastic myelopathy, the pathologic changes have been more chronic, confined to the posterior and lateral columns, and associated with a diffuse loss of cerebellar Purkinje cells. This latter syndrome may have a special association with ovarian carcinoma but has been observed with carcinoma of other types and with Hodgkin disease as discussed in Chap. 30. Most of the reported cases of these types have ended fatally. Steroids and plasma exchanges have been of no clear value. Treatment of the underlying systemic tumor or immunosuppression has also failed in most cases to alter the myelopathy according to Flanagan and colleagues (2011). A rare variety of anterior horn cell destruction that resembles motor neuron diseases is known to occur with certain lymphomas; it is also discussed with the paraneoplastic syndromes in Chap. 30.


Neurology_Adams

Neurology_Adams. Two distinct entities seem to be encompassed under this name, both rare; a progressive myelopathy and a regional disorder, mainly of the abdominal muscles. Whitely and colleagues drew attention to the process characterized clinically by tonic rigidity and intermittent myoclonic jerking of the trunk and limb muscles and by painful spasms of these muscles evoked by sensory or emotional stimuli. Their cases were progressive and eventually involved the limbs.


Neurology_Adams

Neurology_Adams. In the few well-studied cases of this type, the brunt of the pathologic process has fallen on the cervical portion of the spinal cord. Widespread loss of internuncial neurons with relative sparing of the anterior horn cells, reactive gliosis and microglial proliferation, conspicuous lymphocytic cuffing of small blood vessels, and scanty meningeal inflammation have been the main findings. Involvement of the white matter is less marked. The pathophysiology of the rigidity in these cases is presumed to be because of the impaired function (or destruction) of Renshaw cells, with the release of tonic reflexes (Penry et al). The painful spasms and dysesthesias relate in some way to neuronal lesions in the posterior horns of the spinal cord and dorsal root ganglia. Whitely and Lhermitte and their coworkers proposed that these cases probably represent an obscure form of viral myelitis.


Neurology_Adams

Neurology_Adams. The cases we have observed have been of the type that remained confined to several contiguous spinal segments, usually the upper abdomen and lower thorax as described by Brown and colleagues. Some patients report a premonitory sensation before the abdominal jerking, or there is worsening with the supine position. Whether these represent the same disease as the one noted above is unclear but the segmental, abdominal variety is now a firmly established entity, albeit also idiopathic, as described in a series by Roze et al and discussed under “Spinal or Segmental Myoclonus” in Chap. 4. The CSF may be normal or show a mild lymphocytosis and increase in protein content.


Neurology_Adams

Neurology_Adams. Myoclonic jerking of the trunk and limbs in a focal or segmental distribution is probably a result of neuronal damage of this same type that is limited to a few segments of the spinal cord. Clonazepan, various antiepileptic and antispasticity drugs in combination may partially suppress the myoclonus, and local injection of botulinum toxin has improved the symptoms in some. A similar syndrome in a few cases has followed vertebral or spinal artery angiography (see later). A paraneoplastic variety usually associated with breast cancer has been proposed, as in the case described by Roobol and colleagues, but its nature has not been fully elucidated.


Neurology_Adams

Neurology_Adams. In comparison with the brain, the spinal cord is an uncommon site of vascular disease. Blackwood, in a review of 3,737 necropsies at the National Hospital for Nervous Diseases, London, during the period 1903 to 1958, found only 9 cases of spinal cord infarction, but in general hospitals, the incidence (e.g., judged on clinical grounds in our hospital) is higher. The spinal arteries tend not to be susceptible to atherosclerosis, and emboli rarely lodge there. Of all the vascular disorders of the spinal cord, infarction as a result of aortic disease, dural fistula, bleeding, and arteriovenous malformation are the only ones that are encountered with any regularity, but even taken together, they are infrequent in comparison to demyelinating myelitis or compression of the cord by tumor. In current practice, most cases of infarction have developed in relation to operations on the aorta, usually the thoracic portion, where the vessel must be clamped for some period. The dural arteriovenous


Neurology_Adams

Neurology_Adams. practice, most cases of infarction have developed in relation to operations on the aorta, usually the thoracic portion, where the vessel must be clamped for some period. The dural arteriovenous fistulas that cause spinal cord swelling are being recognized increasingly as their clinical syndromes are exposed and vascular imaging of small spinal arteries becomes more sophisticated. They have probably overtaken in frequency cord infarction in this category of disease. An understanding of these disorders requires knowledge of the blood supply of the spinal cord.


Neurology_Adams

Neurology_Adams. Vascular Anatomy of the Spinal Cord The blood supply of the spinal cord is derived from a series of segmental vessels arising from the aorta and from branches of the subclavians and internal iliac arteries. The most important branches of the subclavian are the vertebral arteries, small branches of which give rise to the rostral origin of the anterior spinal artery and to smaller posterolateral spinal arteries that together constitute the major blood supply to the cervical cord. The thoracic and lumbar cord is nourished by segmental arteries arising from the aorta and internal iliac arteries. Segmental branches of the lateral sacral arteries supply the sacral cord.


Neurology_Adams

Neurology_Adams. A typical segmental artery divides into an anterior and a posterior ramus (Fig. 42-6). Each posterior ramus gives rise to a spinal artery, which enters the vertebral foramen, pierces the dura, and supplies the spinal ganglion and roots through its anterior and posterior radicular branches. Most anterior radicular arteries are small and some never reach the spinal cord, but a variable number (4 to 9), arising at irregular intervals, are much larger and supply most of the blood to the spinal cord. Tributaries of the radicular arteries supply blood to the vertebral bodies and surrounding ligaments. The venous drainage is into the posterior veins forming the spinal plexus. Their importance relates to the pathogenesis of fibrocartilaginous embolism (see further on).


Neurology_Adams

Neurology_Adams. Lazorthes, in his thorough review of the circulation of the spinal cord, divides the radiculomedullary arteries into three groups: (1) upper or cervicothoracic, which are derived from the anterior spinal arteries and branches of the thyrocervical and costovertebral arteries; (2) intermediate or middle thoracic (T3 to T8 cord segments), usually from a single T7 radicular artery; and (3) lower or thoracolumbar, from a large T10 or L1 anterior radicular artery, better known as the artery of Adamkiewicz. This artery supplies the lower two-thirds of the cord, but in any individual the precise area supplied by this or any other anterior radiculomedullary artery varies greatly and one cannot predict what portion or proportion of cord will be infarcted if one of these vessels is occluded. The junction between the vertebral spinal and aortic circulations typically lies at the T2-T3 spinal segment, but most ischemic lesions lie well below this level.


Neurology_Adams

Neurology_Adams. The anterior medullary arteries form the single anterior spinal artery, which runs the full length of the cord in its anterior sulcus and gives off direct penetrating branches via the central (sulco-commissural) arteries. These penetrating branches supply most of the anterior gray columns and the ventral portions of the dorsal gray columns of neurons (see Fig. 42-6). The peripheral rim of white matter of the anterior two-thirds of the cord is supplied from a pial radial network, which also originates from the anterior median spinal artery. Thus, the branches of the anterior median spinal artery supply roughly the ventral two-thirds of the spinal cord. Infarction of the region supplied by this artery give rise to an anterior spinal cord syndrome that consists of loss of pain and temperature and paralysis below the level of the lesion, but with sparing of proprioception and vibration sense that correspond to transaction of the spinothalamic and corticospinal tracts but not of the


Neurology_Adams

Neurology_Adams. and paralysis below the level of the lesion, but with sparing of proprioception and vibration sense that correspond to transaction of the spinothalamic and corticospinal tracts but not of the posterior columns.


Neurology_Adams

Neurology_Adams. The posterior medullary arteries form the paired posterior spinal arteries that supply the dorsal third of the cord by means of direct penetrating vessels and a plexus of pial vessels (similar to that of the ventral cord, with which it anastomoses freely). Within the cord substance, then, there is a “watershed” area of capillaries where the penetrating branches of the anterior spinal artery meet the penetrating branches of the posterior spinal arteries and the branches of the circumferential pial network. All spinal segments, because of the variable size of collateral arteries, do not have the same abundance of circulatory protection.


Neurology_Adams

Neurology_Adams. Normally there are 8 to 12 anterior medullary veins and a greater number of posterior medullary veins arranged fairly close to one another at every segmental level. They drain into radicular veins. In addition, a network of valveless veins extends along the vertebral column from the pelvic venous plexuses to the intracranial venous sinuses without passing through the lungs (Batson plexus) and is considered a route for metastatic disease from the pelvis. Infarction of the Spinal Cord


Neurology_Adams

Neurology_Adams. Ischemic infarction of the spinal cord usually involves the territory of the anterior spinal artery, that is, a variable vertical extent of the ventral two-thirds of the spinal cord. Infarctions in this territory are relatively uncommon as already mentioned, representing 1.2 percent of all strokes (Sandson and Friedman). The resulting clinical abnormalities are generally referred to as the anterior spinal artery syndrome, described by Spiller in 1909. Atherosclerosis and thrombotic occlusion of the anterior spinal artery is quite uncommon, as noted, and infarction in the territory of this artery is more often secondary to disease of the extravertebral collateral artery or to disease of the aorta, either advanced atherosclerosis, a dissecting aneurysm, or intraoperative surgical occlusion—which compromises the important segmental spinal arteries at their origins. An ischemic myelopathy has been reported in cocaine users, preceded sometimes by episodes of cord dysfunction resembling


Neurology_Adams

Neurology_Adams. compromises the important segmental spinal arteries at their origins. An ischemic myelopathy has been reported in cocaine users, preceded sometimes by episodes of cord dysfunction resembling transient ischemic attacks. Cardiac and aortic surgery, which requires clamping of the aorta for more than 30 min, and aortic arteriography may also be complicated by infarction in the territory of the anterior spinal artery; more often in these circumstances damage to central neuronal elements is greater than that to anterior and lateral funiculi, as described below.


Neurology_Adams

Neurology_Adams. Rarely, polyarteritis nodosa may cause occlusion of a spinal medullary artery. Systemic cholesterol embolism arising from a severely atheromatous aorta may have the same effect. This latter type of embolism is prone to occur after surgical procedures, angioplasty, or cardiopulmonary resuscitation. For unexplained reasons, the spinal cord infarction sometimes follows one of the aforementioned procedures by up to 3 weeks, as emphasized in Dahlberg’s series of cases (Dahlberg et al). In almost all such patients, other evidence of widespread embolism can be expected. Infarction may also result from systemic hypotension, the most vulnerable part being of the thoracic segments of the cord. One of our patients had cord infarction during a bout of diabetic coma.


Neurology_Adams

Neurology_Adams. Among the most curious causes of cervical cord infarction is dissection of the extracranial vertebral arteries, either unilateral or bilateral. The resultant ischemia in the territories of the anterior spinal arteries causes anterior and central cervical cord ischemia. In two cases of this nature that have been brought to our attention, there were an asymmetric brachial diplegia and a suspended sensory loss, preceded by intense radicular and neck pain. The patients reported by Weidauer and colleagues are representative, and there are numerous other case reports although the cause of the vertebral artery dissections has not always been clear. A few patients have vertigo at the onset, directing attention to the vertebral artery damage. We have also encountered instances of myelomalacia in adolescents and young adults in whom no aortic or spinal arterial disease could be demonstrated. Possibly, some of these were because of embolization of disc material (nucleus pulposus) into the local


Neurology_Adams

Neurology_Adams. and young adults in whom no aortic or spinal arterial disease could be demonstrated. Possibly, some of these were because of embolization of disc material (nucleus pulposus) into the local vasculature (see further on).


Neurology_Adams

Neurology_Adams. A quite different progressive ischemic necrosis of the cord can occur in the neighborhood of an arteriovenous malformation or dural fistula and is considered later in this chapter (see also the section on Foix-Alajouanine Myelopathy, described earlier).


Neurology_Adams

Neurology_Adams. Despite the elucidation of these causes of spinal cord infarction, a large group in any series has no identifiable cause; for example, an etiology could be established in only 7 of 27 consecutive cases in the series from Novy and colleagues. The clinical manifestations of spinal arterial occlusion will, of course, vary with the level and portions of the cord that are infarcted, but common to practically all cases of infarction in the territory of the anterior spinal artery is pain in the neck or back and the development of paralysis and loss of pain and thermal sensations below the level of the lesion, accompanied by paralysis of sphincteric function. Except in high cervical lesions, the sensory changes are dissociated, that is, pain and temperature sensations are lost (because of interruption of the spinothalamic tracts), but vibration and position sense are unimpaired (a result of sparing of posterior columns).


Neurology_Adams

Neurology_Adams. Rarely, infarction is preceded by spinal transient ischemic attacks as has been emphasized in cases related to cocaine use. The symptoms may develop instantaneously or, more often in our experience, over 1 or 2 h; in any case, more rapidly than in the inflammatory myelitides. Radicular pain corresponding to the upper level of the lesion is sometimes a complaint. Paralysis is usually bilateral, occasionally unilateral, and rarely complete. Also reported is a bibrachial paralysis as a fragment of the anterior spinal artery syndrome, as mentioned earlier. In cases that cause a complete transverse myelopathy, the limbs are initially flaccid and areflexic, as in spinal shock from traumatic lesions, followed after several weeks by the development of spasticity and the return of a degree of voluntary bladder control (unless sacral segments have been infarcted). Many patients regain a substantial degree of motor function, mainly in the first month but extending over a year (see Sandson and


Neurology_Adams

Neurology_Adams. bladder control (unless sacral segments have been infarcted). Many patients regain a substantial degree of motor function, mainly in the first month but extending over a year (see Sandson and Friedman; Cheshire et al; Novy et al).


Neurology_Adams

Neurology_Adams. Infarction in the territory of the posterior spinal arteries is uncommon and the corresponding syndrome is not stereotyped; only 2 of 27 cases from the series by Novy and colleagues had this pattern. It may occur with surgery or trauma of the spine or rarely with vertebral artery dissections. Some, but not all, spinal cord infarctions are detected by MRI (Fig. 42-7). After a few days, there are obvious lesions on the T2 sequences, presumably reflecting edema that extends over several levels. There may be slight enhancement after infusion of gadolinium. It is notable, however, that the MRI taken in the first hours or day is often normal, including sometimes diffusion weighted images. The reason for the delay in the appearance of the imaging findings is not known. In the chronic stages, the infarcted region collapses and has an attenuated signal on MRI.


Neurology_Adams

Neurology_Adams. Dissecting aneurysm of the aorta, which is characterized by intense interscapular and/or chest pain (occasionally it is painless), widening of the aorta, and signs of impaired circulation to the legs or arms and various organs, gives rise to a number of myelopathic syndromes. The neurologic picture was first described by Kalischeri in 1914 and the aortic lesion leading to dissection, according to Erdheim, was a medionecrosis. The spinal syndromes of aortic dissection according to Weisman and Adams are (1) paralysis of the sphincters and both legs with sensory loss below T6; (2) ischemic infarction of the cord confined to the gray matter, in which case there is an abrupt onset of muscle weakness or myoclonus and spasms in the legs but no pain or sensory loss; (3) obstruction of the origin of a common carotid artery with hemiplegia; and, less commonly, (4) obstruction of a brachial artery with a sensorimotor neuropathy of the limb.


Neurology_Adams

Neurology_Adams. With regard to aortic aneurysm surgery, paraplegia is uncommon after procedures performed on the infrarenal segment but occurs as frequently as 5 to 10 percent following repair of thoracoabdominal aneurysms. Again emphasized here is the not easily explained observation that up to a quarter of these myelopathies do not appear for several days postoperatively (8 days in one of our patients). The article by Lintott and colleagues may be consulted for further details.


Neurology_Adams

Neurology_Adams. In the past, aortography was sometimes complicated by an acute myelopathy; we had observed a number of such cases and Killen and Foster reviewed 43 examples of this accident. The most striking examples, fortunately rare, are now the result of complications of vertebral angiography, resulting in high cervical infarction, similar in most ways to the aforementioned spinal infarction from extracranial dissection of the vertebral artery. The onset of sensorimotor paralysis is immediate, and the effects are often permanent. The syndrome of painful segmental spasms, spinal myoclonus, and rigidity, mentioned earlier, has also been observed under these conditions. It was presumed that vascular spasm and occlusion resulted in infarct necrosis. The frequency of this complication was greatly reduced by the introduction of less toxic contrast media.


Neurology_Adams

Neurology_Adams. Treatment Whether the acute effects of spinal infarction can be modified by high-dose corticosteroids, agents that increase blood flow, or anticoagulation is not known. There are case reports of improvement in paraplegia following aortic dissection by the use of CSF drainage, for example, as in the cases reported by Blacker and colleagues and by Killen and associates, but other factors may have contributed. Many surgical services insert a spinal drain prior to aortic procedures in order to reduce spinal fluid pressure, ostensibly reducing the incidence of cord infarction. There may be gradual improvement after spinal cord infarction, as Robertson and colleagues have reported in perhaps the largest series available, but most patients remain with substantial difficulties.


Neurology_Adams

Neurology_Adams. This unusual nontraumatic athletic problem has been described by Thompson and colleagues from Hawaii. It mainly affects novice surfers who were prone for prolonged times on the surfboard and then engaged in vigorous movements, followed by assuming a standing position. Within an hour of surfing, there was characteristic severe upper lumbar or thoracic pain after, followed by progressive paraparesis or paraplegia, and urinary retention. In several reports, MRI showed signal changes in a long extent of the thoracic spinal cord and when the proper imaging sequences have been performed, some cases have restricted diffusion in the affected region. On the basis of the latter finding and preservation of proprioception some patients (implicating ischemia of the anterior portion of the spinal cord), a vascular mechanism has been proposed. In the series reported by Chang and colleagues, improvement was inconsistent. Hemorrhage of the Spinal Cord (Hematomyelia) and Spinal Canal


Neurology_Adams

Neurology_Adams. Hemorrhage of the Spinal Cord (Hematomyelia) and Spinal Canal Hemorrhage into the spinal cord is rare compared with the frequency of cerebral hemorrhage. The apoplectic onset of symptoms that involve spinal tracts (motor, sensory, or both), associated with blood and xanthochromia in the spinal fluid are the identifying features of hematomyelia. Aside from trauma, hematomyelia is usually traceable to a vascular malformation or a bleeding disease and particularly to the administration of anticoagulants. Actually, most vascular malformations of the spinal cord do not cause hemorrhage, but instead produce a progressive, presumably ischemic myelopathy as described later and mentioned in the earlier section on the Foix-Alajouanine type of subacute necrotic myelopathy.


Neurology_Adams

Neurology_Adams. The same causes (anticoagulation, blood dyscrasia with coagulopathy, and arteriovenous malformation [AVM]) may underlie bleeding into the epidural or subdural space and give rise to a rapidly evolving compressive myelopathy. In some cases, as in those of Leech and coworkers, one cannot ascertain the source of the bleeding, even at autopsy. Epidural or subdural bleeding, like epidural abscess, represents a neurologic emergency and calls for immediate localization by imaging and, in some cases, surgical evacuation.


Neurology_Adams

Neurology_Adams. Advances in the techniques of selective spinal angiography and microsurgery have permitted the visualization and treatment of vascular lesions that cause bleeding with a precision not imaginable a few decades ago. These procedures make it possible to distinguish among the several types of vascular malformations, arteriovenous fistulas, and vascular tumors, such as hemangioblastomas, and to localize them accurately to the spinal cord, epidural or subdural space, or vertebral bodies. This subject is discussed further on. Vascular Malformations and Dural Fistulas of the Spinal Cord


Neurology_Adams

Neurology_Adams. These lesions cause both ischemic and hemorrhagic lesions. Some are true arteriovenous malformations (AVMs), implying a congenital connection between the two sides of the circulation and others are more limited fistulas in the dura, probably mostly acquired for various reasons. The distinction is in the size of the nidus of communication between an artery and a vein and the size and location of feeding and draining vessels. The classification of spinal AVMs is confusing, in part because the enlarged draining veins by which the lesions were formerly identified are probably secondary features. A more useful categorization reflects the appearance and location of the malformation: (1) arteriovenous malformations that are strictly intramedullary or that also involve the meninges and surrounding structures, such as the vertebral bodies, to a limited extent; (2) a variety of intradural perimedullary fistulas that lie on the pial and subpial surface of the cord (these probably conform most


Neurology_Adams

Neurology_Adams. structures, such as the vertebral bodies, to a limited extent; (2) a variety of intradural perimedullary fistulas that lie on the pial and subpial surface of the cord (these probably conform most closely to the lesion described by Foix and Alajouanine discussed in the earlier section “Foix-Alajouanine Myelopathy”); and (3) dural fistulas. There is insufficient pathologic material to determine whether these represent distinct pathologic entities or simply differing degrees and configurations of a common developmental process but, as mentioned, the last of these types may be acquired from local venous occlusions and the other types do not originate in this way. Once recognized, treatment of a spinal cord malformation of any type may be an urgent matter, especially in cases with rapid clinical deterioration and impending paralysis.


Neurology_Adams

Neurology_Adams. Dural arteriovenous fistula The entity is addressed first because it has emerged as the most common type, at least in our practices. Fistulas within the dura that overlies the spinal cord are capable of causing a myelopathy, sometimes several segments distant from the vascular lesion. Most are situated in the region of the low thoracic cord or the conus and have a limited venous draining system. Some are in a dural root sleeve and drain into the normal perimedullary coronal venous plexus. Men seem to be affected disproportionately.


Neurology_Adams

Neurology_Adams. The presenting clinical features in our patients have included slowly progressive bilateral but asymmetric leg weakness with variable sensory loss. According to Jellema and colleagues, who studied 80 patients with spinal dural fistulas, the most common initial symptoms were gait imbalance, numbness, and paresthesias. As the process progressed, the majority developed urinary problems, leg weakness, and numbness in the legs and buttocks. The degree of leg weakness varied greatly and back pain in their series was infrequent and has not been a consistent feature in the patients under our care.


Neurology_Adams

Neurology_Adams. The myelopathy may have a subacute or saltatory evolution, presumably from fluctuating venous congestion within the cord. A claudicatory syndrome has also been reported. Characteristically, activities that increase venous pressure (Valsalva maneuver, exercise) transiently amplify the symptoms or produce irreversible, stepwise worsening. One remarkable such case involved a baritone opera singer whose legs gave way repeatedly while singing (Khurana et al). A few of our patients have reported transient symptoms upon standing. Many cases occur, however, without a stepwise progression or elicitable worsening. As mentioned, many reported cases have been painless, although most of our patients have had a moderate spinal ache or sciatica. In contrast to the larger parenchymal arteriovenous lesions, these bleed only rarely. The spinal fluid is normal or shows a slight elevation of protein.


Neurology_Adams

Neurology_Adams. The disease can be inferred from the MRI appearance of a characteristic swelling of one or a few adjacent segments of the lower cord that represents venous congestion and edema as discussed further on. Intramedullary AVM The true spinal cord AVM, previously referred to as angioma racemosum venosum or dorsal extramedullary arteriovenous malformation, is typically located on the dorsal surface of the lower half of the spinal cord and occurs most often in middle-aged and elderly men (23 of 25 of Logue’s patients were male). However, this lesion may occur at any age and at any location in the cord and may be quite widespread. In a few cases has there been an overlying dermatomal nevus.


Neurology_Adams

Neurology_Adams. The clinical picture was well described by Wyburn-Mason. Acute cramp-like, lancinating pain, sometimes in a sciatic distribution, is often a prominent early feature. It may occur in a series of episodes over a period of several days or weeks; sometimes it is worse in recumbency. Almost always there is weakness or paralysis of one or both legs and numbness and paresthesias in the same distribution with a highly variable duration of evolution; an abrupt apoplectic onset is known or the neurologic signs may appear over months, most cases conforming to the middle of these extremes. Wasting and weakness of the legs may introduce the disease in some instances, with uneven progression, sometimes in a series of abrupt episodes. Severe disability of gait is usually present within 6 months, and half of the patients described by Aminoff and Logue were chair-bound within 3 years; the average survival in the past was 5 to 6 years, but the disorder has rarely been fatal in our patients. These


Neurology_Adams

Neurology_Adams. half of the patients described by Aminoff and Logue were chair-bound within 3 years; the average survival in the past was 5 to 6 years, but the disorder has rarely been fatal in our patients. These lesions only infrequently give rise to intramedullary or subarachnoid hemorrhage. The spinal fluid shows high protein but little or no cellular reaction.


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Neurology_Adams. When viewed directly, the dorsal surface of the lower cord may be covered with a tangle of veins, some involving roots and penetrating the surface of the cord. The progression of symptoms is presumably a result of chronic venous hypertension and secondary intramedullary ischemic changes, and the abrupt episodes of worsening are attributed to the thrombosis of vessels, all on uncertain grounds because angiographic studies sometimes show only a single or a few such dilated draining vessels. Furthermore, there is insufficient pathologic material to determine whether some of the more prominent venous anomalies represent true venous angiomas (probably they do not).


Neurology_Adams

Neurology_Adams. Intradural perimedullary and subpial AVM The pial fistulous arteriovenous communication that involves the superficial aspect of the cord to a variable extent is the least frequent in this category but probably of a similar nature to the dural type; it may be related (or identical) to the vascular lesion in the earlier discussed Foix-Alajouanine process. In contrast to dorsal arteriovenous malformations, these fistulas tend to involve the lower thoracic and upper lumbar segments or the anterior parts of the cervical enlargement. The patients are often younger and the sexes are equally affected. The clinical syndrome may take the form of slow spinal cord compression, sometimes with a sudden exacerbation, or the initial symptoms may be apoplectic in nature, either because of thrombosis of a vessel or of a hemorrhage from an associated draining vein that dilates to aneurysmal size and bleeds into the subarachnoid space or cord (hematomyelia and subarachnoid hemorrhage); the latter


Neurology_Adams

Neurology_Adams. of a vessel or of a hemorrhage from an associated draining vein that dilates to aneurysmal size and bleeds into the subarachnoid space or cord (hematomyelia and subarachnoid hemorrhage); the latter complication occurred in 7 of 30 cases reported by Wyburn-Mason.


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Neurology_Adams. Diagnosis These lesions—dural or parenchymal—may be apparent on MRI or CT myelography by the presence of one or more enlarged and serpiginous draining vessels in the subarachnoid space; just as often, they are not visualized by these methods (Jones et al). For this reason, the possibility should come to mind that an otherwise unexplained myelopathy with signs of congestion of the cord on MRI may be the result of a vascular malformation. However, several studies, such as the one by Toossi and colleagues, have suggested that the absence of both T2 hyperintensity and flow voids on MRI makes the presence of a dural fistula unlikely and spares the patient from the need for angiography.


Neurology_Adams

Neurology_Adams. Imaging features that have been emphasized with dural fistulas include enlargement of the spinal cord at the level of the lesion and T2 bright signal of the swollen cord over several segments, but these are not invariable. Infrequently, the draining surface vessels are evident on MRI (Fig. 42-8A). Because of the slow blood flow within the vascular lesion, the affected region may have a hypointense T1 signal. Hurst and Grossman have commented on the presence of peripherally located regions of T2 hypointense signal changes. Many of these changes are reversed by surgical or endovascular interventions that ablate the malformation. There is variable enhancement although, with increasingly improved MRI techniques, more fistulas are becoming apparent. Some remarkable ones appear as a multiple small enhancing areas that are like hairs standing on end, coating the cord over several levels.


Neurology_Adams

Neurology_Adams. The diagnosis is usually established through selective angiography, which shows the fistula in the dura overlying the cord or on the surface of the cord itself but the most conspicuous finding is often the associated early draining vein (Fig. 42-8B). Demonstration of the fistula requires the injection of feeding vessels at numerous levels above and below the suspected lesion, because the main artery of origin is often some distance away from the malformation. The small angiodysplastic vessels of the Foix-Alajouanine lesion may not be opacified with angiography. In rare instances, the fistula or high-flow arteriovenous malformation lies well outside the cord, for example, in the kidney, and gives rise to a myelopathy, presumably by raising venous pressures within the cord.


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Neurology_Adams. Other rare vascular anomalies of the cord In the Klippel-Trenaunay-Weber syndrome, a sometimes extensive vascular malformation of the spinal cord is associated with a cutaneous vascular nevus overlying the AVM or in a limb supplied by the affected cord level; when the malformation lies in the low cervical region, there may be enlargement of finger, hand, or arm (the hemangiectatic hypertrophy of Parkes Weber; neurofibromatosis is another cause of limb enlargement). Spinal segmental and tract lesions may occur at any age, but the patients we have observed were young adults. Vascular occlusion or hemorrhage was responsible for the myelopathy. Some of these vascular lesions have been treated by defining and ligating their feeding vessels. In a few reported cases it has been possible to extirpate the entire lesion, especially if it occupied the surface of the cord.


Neurology_Adams

Neurology_Adams. Other rare vascular anomalies of the spinal cord include aneurysm of a spinal artery with coarctation of the aorta and telangiectasia of the cord, which may or may not be associated with the hereditary hemorrhagic type of Osler-Rendu-Weber. Over the years, the authors have had under their care patients with the latter disease who developed acute hemorrhagic lesions of the spinal cord. We have also observed several cavernous hemangiomas of the spinal cord. In two of our patients, an angiographically negative solitary cavernous angioma was the source of an acute partial transverse myelopathy. The lesions were clearly demonstrable only in the T2-weighted MR images. McCormick and associates have reported similar cases. Characteristically, the angiomas cause partial syndromes and are followed by considerable recovery of function just as when they occur in the brain. There may or may not be blood in the CSF. Rarely, the same disease is responsible for one or more hemorrhagic lesions of the


Neurology_Adams

Neurology_Adams. by considerable recovery of function just as when they occur in the brain. There may or may not be blood in the CSF. Rarely, the same disease is responsible for one or more hemorrhagic lesions of the brain. The association of cavernous angiomas with arteriovenous fistulas of the lung is a rare finding, and the latter may be a source of brain abscess. In coarctation of the aorta, the circulation to the lower part of the spinal cord may be deficient, with resultant paresis of the legs, sensory loss, and sphincteric impairment. Or there may be intracranial subarachnoid hemorrhage from a ruptured saccular aneurysm, an associated condition in a small number of cases.


Neurology_Adams

Neurology_Adams. Treatment The rate of progression of the myelopathy from these various lesions varies greatly. In some cases, as already noted, it may become a matter of some urgency to reverse the venous congestion and avoid infarction of the cord. Other lesions require a more measured approach. By occluding the feeding artery of a spinal AVM or fistula, which is often single, and thereby eliminating the excess pressure in veins, the course of disease can be arrested and any pain reduced (Symon et al). In most of our patients, there has been postoperative improvement in the neurologic deficit over a few weeks or months. In cases of the larger racemose AVMs, stripping the enlarged veins along the dorsal cord is no longer considered necessary and may be dangerous. Increasingly, one resorts to obliteration of a fistula or a reduction of the AVM by the use of endovascular techniques and various types of embolic particles. The procedure is long and painstaking, for the operator must identify and embolize


Neurology_Adams

Neurology_Adams. of a fistula or a reduction of the AVM by the use of endovascular techniques and various types of embolic particles. The procedure is long and painstaking, for the operator must identify and embolize all the feeding vessels of the malformation; general anesthesia is required in most cases.


Neurology_Adams

Neurology_Adams. This approach has certain drawbacks; recanalization occurs months later in many instances, as does distal occlusion of the venous drainage system with worsening of the myelopathy. For these reasons, surgical ligation of the arterial supply is still preferred as the initial procedure for larger AVMs. Some surgeons advise a staged approach in which the size of the malformation is first reduced by endovascular techniques, thereby making the surgery less complicated. Intradural fistulas are usually treated by endovascular methods but they can be excised if visualized intraoperatively. Interventional techniques have also been used to advantage in the intramedullary malformations, either as the sole treatment or in combination with surgery. Focused radiation has been tried but the results have been difficult to evaluate.


Neurology_Adams

Neurology_Adams. Naiman and coworkers described the case of an adolescent boy who died of sudden paralysis after a fall in a seated position. Postmortem examination revealed extensive myelomalacia as a result of occlusions of numerous spinal vessels by emboli of nucleus pulposus material. The clinical picture is essentially one of spinal apoplexy; after spinal trauma of even mild degree the patient experiences the abrupt onset of pain in the back or neck, accompanied by the signs of a transverse cord lesion affecting all sensory, motor, and sphincteric functions and evolving over a period of a few minutes to 1 h or more. Occasionally, the syndrome spares the posterior columns, thus simulating an anterior spinal artery occlusion. The CSF is normal. As with other types of cord infarction, the changes may not appear on MRI for a day or more.


Neurology_Adams

Neurology_Adams. In some of the reported instances there was said to have been no excessive activity or spinal trauma preceding the spinal cord symptoms. However, this has not been true of our patients, most of who had been participating in some strenuous activity, but often earlier in the day rather than at the time of the paraplegia. Others had fallen and injured themselves on preceding days; a direct blow to the back during contact athletic sports was the antecedent event in several others and is the easiest-to-understand cause.


Neurology_Adams

Neurology_Adams. At autopsy, numerous small arteries and veins within the spinal cord are occluded by fibrocartilage, with necrosis of the spinal cord over 1 or 2 segments. A ruptured disc of the usual type is usually not found in these patients, but high-resolution radiographs have exposed a discontinuity of the cortical bone of the vertebral body adjacent to a collapsed disc and herniation of disc tissue into a vertebral body in a few instances (Tosi et al). The explanation suggested by Yogananden and colleagues is that the high intravertebral pressure forces nucleus pulposus material into venules and arteries of the marrow of the vertebral body, and thence into the adjacent radicular vessels. This mechanism has probably been overlooked in some otherwise unexplained cases of acute ischemic myelopathy. Caisson Disease (Decompression Sickness, “Bends”)


Neurology_Adams

Neurology_Adams. This extraordinary myelopathy, which is well known to the scuba diving community, is observed in persons who are subjected to high underwater pressure and then ascend too rapidly. It affects mainly the upper thoracic spinal cord as a result of nitrogen bubbles that form and are trapped in spinal vessels. There may be little or no involvement of the brain. Haymaker, who provided the most complete account of the neuropathologic changes, observed ischemic lesions mainly in the white matter of the upper thoracic cord; the posterior columns were more affected than lateral and anterior ones. We have encountered instances in which an almost complete transverse myelopathy was evident soon after the patient resurfaced but the syndrome then improved, leaving the patient with an asymmetrical and incomplete albeit permanent residual deficit. The smallest degree of damage is manifest as a minor myelopathy that affects the anterior or the posterior funiculi, leaving either spasticity or numbness of


Neurology_Adams

Neurology_Adams. albeit permanent residual deficit. The smallest degree of damage is manifest as a minor myelopathy that affects the anterior or the posterior funiculi, leaving either spasticity or numbness of the legs. Immediate treatment consists of recompression in a hyperbaric chamber; later treatment is symptomatic, with antispasticity drugs and physical therapy.


Neurology_Adams

Neurology_Adams. This is an unusual process but we have reported cases that presented with excruciating thoracic back pain of such severity as to cause a bizarre, almost psychotic, reaction (Swann et al). The neck becomes slightly stiff and there may be a headache, suggesting subarachnoid hemorrhage. However, signs of a myelopathy do not appear, indicating that the bleeding is confined to the pliable subdural spaces surrounding the cord, thereby allowing the blood to spread over several segments.


Neurology_Adams

Neurology_Adams. Lumbar puncture yields a distinctive dark yellow-brown spinal fluid that resembles, to us, used motor oil. The color is imparted by methemoglobin and reflects the presence of an adjacent, decomposing walled-off clot. Usually there are also red blood cells in the CSF, suggesting seepage into the subarachnoid space from the adjacent collection. MRI or CT myelography shows a subdural collection, with characteristically smooth borders. When drained operatively, this is found to be clotted blood. Usually, no vascular malformation is demonstrable and the cause remains obscure. Trauma or anticoagulation underlies a few cases but many are spontaneous. The symptoms resolve in 1 or 2 weeks after removal of the subdural hematoma. Small collections may be managed without surgery, in which case corticosteroids may be helpful in reducing the pain.


Neurology_Adams

Neurology_Adams. The syndrome of spinal subarachnoid hemorrhage has been mentioned earlier and is also covered in Chap. 33 under “Other Causes of Intracranial Bleeding and Multiple Cerebral Hemorrhages.”


Neurology_Adams

Neurology_Adams. The gradual development of weakness of the legs is the common manifestation of many diseases of the spinal cord. A syndrome of this type, including ataxia of gait beginning insidiously in late childhood or adolescence and progressing steadily, is usually indicative of hereditary spinocerebellar degeneration (Friedreich ataxia) or one of its variants (see Chap. 38). In early adult life, MS is the most frequent cause and HIV myelopathy is being increasingly recognized; syphilitic meningomyelitis, formerly of great importance, is now quite uncommon. In middle and late adult life, cervical spondylosis, subacute combined degeneration of the cord (vitamin B12 deficiency), combined system degeneration of the nonpernicious anemia type, some associated with low levels of serum copper, radiation myelopathy, tropical spastic paraplegia, spinal arachnoiditis, and thoracic spinal tumor, particularly meningioma, are the important diagnostic considerations for the slowly progressive cord syndrome.


Neurology_Adams

Neurology_Adams. tropical spastic paraplegia, spinal arachnoiditis, and thoracic spinal tumor, particularly meningioma, are the important diagnostic considerations for the slowly progressive cord syndrome. In most forms of subacute and chronic spinal cord disease, spastic paraparesis is more prominent than posterior column ataxia, Friedreich ataxia and the myelopathy caused by vitamin B12 deficiency being notable exceptions.


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Neurology_Adams. (See earlier under “Acute Demyelinating Myelitis of Multiple Sclerosis” and also Chap. 35 for a discussion of multiple sclerosis.)


Neurology_Adams

Neurology_Adams. Ataxic paraparesis is among the most common manifestations of MS. Asymmetrical involvement of the limbs and signs of cerebral, optic nerve, brainstem, and cerebellar involvement usually provide confirmatory diagnostic evidence. Nevertheless, purely spinal involvement may occur, no lesions being found outside the spinal cord even at autopsy. A frequent problem in diagnosis is posed by the older woman who was not known to have had MS in earlier life, previous episodes having been absent, asymptomatic, or forgotten. A secondary progressive stage of spinal multiple sclerosis is the consequence of recurrent demyelinating attacks. There is another group, however, in which slowly advancing neurologic deterioration represents the primary manifestation of the disease. The National Hospital Research Group examined 20 cases of the secondary progressive type of spinal MS and 20 of the primary type by gadolinium-enhanced MRI of the spinal cord and brain and found new lesions in only 3 of each


Neurology_Adams

Neurology_Adams. Group examined 20 cases of the secondary progressive type of spinal MS and 20 of the primary type by gadolinium-enhanced MRI of the spinal cord and brain and found new lesions in only 3 of each group (Kidd et al). They suggest that the progression correlates better with progressive atrophy of the spinal cord than with recurrent demyelinative lesions.


Neurology_Adams

Neurology_Adams. This clinical state must be differentiated from cervical disc disease, spondylosis, and tumor. The main aids in diagnosis are the CSF findings (minor pleocytosis and oligoclonal IgG abnormalities), present in 70 to 90 percent of cases, the demonstration by MRI of other unsuspected white matter lesions in the spinal cord and brain. Cervical Spondylosis With Myelopathy (Spondylitic Myelopathy) (See Also Chap. 10) It has been stated, correctly in our opinion, that this is the most frequently observed myelopathy in general practice. It is a degenerative disease of the spine involving the lower and midcervical vertebrae that narrows the spinal canal and intervertebral foramina and causes progressive injury of the spinal cord, roots, or both.


Neurology_Adams

Neurology_Adams. Historical note Key, in 1838, probably gave the first description of a spondylotic bar, or ossified protrusion into the spinal canal. In 2 cases of compressive myelopathy with paraplegia, he found “a projection of the inter-vertebral substance and posterior ligament of the spine, which was thickened and presented as a firm ridge that had lessened the diameter of the canal by nearly a third.” The ligament, where it passes over the posterior surface of the intervertebral substance, was found to be “ossified.” In 1892, Horsley performed a cervical laminectomy on such a patient, removing a “transverse ridge of bone” compressing the spinal cord at the level of the sixth cervical vertebra. Thereafter, operations were performed in many cases of this sort, and the tissues removed at operation were repeatedly misidentified as benign cartilaginous tumors or “chondromata.” In 1928, Stookey described the pathologic effects upon the spinal cord and roots of these “ventral extradural chondromas.”


Neurology_Adams

Neurology_Adams. repeatedly misidentified as benign cartilaginous tumors or “chondromata.” In 1928, Stookey described the pathologic effects upon the spinal cord and roots of these “ventral extradural chondromas.” Peet and Echols, in 1934, were probably the first to suggest that the so-called chondromata represented protrusions of disc material. But this idea never gained wide credence until the publication, in the same year, of the classic article on the ruptured intervertebral disc by Mixter and Barr. Although their names are associated with the lumbar disc syndrome, 4 of their original 19 cases were instances of cervical disc disease. It was C.S. Kubik who identified the extruded material as nucleus pulposus from surgical specimens obtained by Mixter and Barr at operation.


Neurology_Adams

Neurology_Adams. Also of importance is Gowers’ account, in 1892, of vertebral exostoses, in which he described osteophytes that protrude from the posterior surfaces of the vertebral bodies and encroach upon the spinal canal, causing slow compression of the cord as well as bony overgrowth in the intervertebral foramina, giving rise to radicular pain. Gowers correctly predicted that these lesions would offer a more promising field for the surgeon than would other kinds of vertebral tumors.