10.14639/0392-100X-N2255
Objectives. To identify pre-operative radiological parameters that are able to predict the functional outcomes of open partial horizontal laryngectomy (OPHL). Methods. The present retrospective study concerned a cohort of 96 patients with laryngeal squamous cell carcinoma who underwent pre-operative radiological staging with contrastenhanced computerised tomography of the neck, and subsequent supracricoid or supratracheal laryngectomy. Univariate and multivariate analyses were run to assess the prognostic value of the main demographic and surgical variables, and the pre-operative cephalometric values, respectively, in terms of predicting patients’ functional outcomes. Results. Multivariate analysis showed that a larger anteroposterior cross-sectional dimension of the aero-digestive tract in the mid-retroglossal area, and a greater distance between the genial tubercle and the hyoid bone in the mid-sagittal plane correlated significantly with better functional outcomes in terms of decannulation rate at discharge. Conclusions. Our findings show that larger pre-operative upper aero-digestive tract diameters and volumes coincide with better post-operative functional outcomes after OPHL.
text/xml
1827-675X
2255
en
Andy Bertolin
http://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
computerised tomography
Pre-operative CT cephalometry and functional outcomes after open partial horizontal laryngectomy
Text.Serial.Journal
https://www.actaitalica.it/
43
Laryngology
2023-04-26
2022-08-02
2023-04-27
2023-04-27
123-129
1
Andy Bertolin
2023/04/26
10.14639/0392-100X-N2255
123
Otolaryngology Unit, Vittorio Veneto Hospital, Treviso, Italy
1827-675X
computerised tomography
en
129
Pre-operative CT cephalometry and functional outcomes after open partial horizontal laryngectomy
https://www.actaitalica.it/article/download/2255/960
43
ACTA OTORHINOLARYNGOLOGICA ITALICA 2023;43:123-129; doi: 10.14639/0392-100X-N2255




Laringology


Pre-operative CT cephalometry and functional
outcomes after open partial horizontal laryngectomy
Cefalometria TC pre-operatoria ed esiti funzionali dopo laringectomia parziale
orizzontale
Marco Lionello1, Cristina Cercato2, Chiara Varago3, Leonardo Franz3, Saverio Grillone2, Gianluca Piccoli2, Piero Nicolai3,
Andy Bertolin1
1
    Otolaryngology Unit, Vittorio Veneto Hospital, Treviso, Italy; 2 Radiology Unit, Vittorio Veneto, Conegliano Hospital, Treviso, Italy;
3
    Neuroscience Department, Otolaryngology Section, University of Padua, Padua, Italy


SUMMARY
Objectives. To identify pre-operative radiological parameters that are able to predict the
functional outcomes of open partial horizontal laryngectomy (OPHL).
Methods. The present retrospective study concerned a cohort of 96 patients with laryngeal
squamous cell carcinoma who underwent pre-operative radiological staging with contrast-
enhanced computerised tomography of the neck, and subsequent supracricoid or supratra-
cheal laryngectomy. Univariate and multivariate analyses were run to assess the prognostic
value of the main demographic and surgical variables, and the pre-operative cephalometric
values, respectively, in terms of predicting patients’ functional outcomes.
Results. Multivariate analysis showed that a larger anteroposterior cross-sectional dimen-
sion of the aero-digestive tract in the mid-retroglossal area, and a greater distance between
the genial tubercle and the hyoid bone in the mid-sagittal plane correlated significantly with
better functional outcomes in terms of decannulation rate at discharge.
Conclusions. Our findings show that larger pre-operative upper aero-digestive tract diam-
eters and volumes coincide with better post-operative functional outcomes after OPHL.
KEY WORDS: cephalometry, open partial horizontal laryngectomy, functional outcome,
decannulation, computerised tomography
                                                                                                 Received: August 2, 2022
RIASSUNTO                                                                                        Accepted: January 14, 2023
Obiettivi. Identificare i parametri radiologici pre-operatori in grado di predire l’outcome
funzionale dei pazienti sottoposti a laringectomia parziale orizzontale a cielo aperto (OPHL)    Correspondence
                                                                                                 Marco Lionello
Metodi. Questo studio retrospettivo ha considerato una coorte di 96 pazienti affetti da
                                                                                                 Otolaryngology Unit, Vittorio Veneto Hospital, via
carcinoma squamocellulare della laringe che sono stati sottoposti a staging radiologico
                                                                                                 Forlanini 71, Vittorio Veneto, Treviso, Italy
pre-operatorio con tomografia computerizzata del collo con mezzo di contrasto, e succes-         E-mail: marcolionello@email.it
sivamente sottoposti a laringectomia parziale sovracricoidea o sovratracheale. Sono state
condotte analisi statistiche uni- e multivariate per verificare il valore prognostico delle
principali variabili demografiche e chirurgiche, e dei valori cefalometrici pre-operatori,         How to cite this article: Lionello M, Cercato
rispettivamente, nel predire gli outcomes funzionali.                                              C, Varago C, et al. Pre-operative CT cepha-
                                                                                                   lometry and functional outcomes after open
Risultati. L’analisi multivariata ha evidenziato che un maggiore diametro antero-posterio-
                                                                                                   partial horizontal laryngectomy. Acta Otorhi-
re dell’area retrolinguale della via aereo-digestiva, e una maggiore distanza fra il il tuber-     nolaryngol Ital 2023;43:123-129. https://doi.
colo genieno e l’osso ioide nel piano sagittale mediano hanno correlato significativamente         org/10.14639/0392-100X-N2255
con migliori risultati funzionali in termini di tasso di decannulazione alla dimissione.
Conclusioni. I nostri risultati hanno evidenziato che maggiori diametri e volumi pre-ope-        © Società Italiana di Otorinolaringoiatria
ratori della via aereo-digestiva correlano con i migliori risultati funzionali dopo OPHL.        e Chirurgia Cervico-Facciale

PAROLE CHIAVE: cefalometria, laringectomia parziale orizzontale, risultati funzionali,
                                                                                                                OPEN ACCESS
decannulazione, tomografia computerizzata
                                                                                                 This is an open access article distributed in accordance with
                                                                                                 the CC-BY-NC-ND (Creative Commons Attribution-Non-
Introduction                                                                                     Commercial-NoDerivatives 4.0 International) license. The
                                                                                                 article can be used by giving appropriate credit and mentio-
                                                                                                 ning the license, but only for non-commercial purposes and
In recent decades, open partial horizontal laryngectomy (OPHL) has come to be                    only in the original version. For further information: https://
adopted largely as a conservative surgical option for treating selected cases of                 creativecommons.org/licenses/by-nc-nd/4.0/deed.en




                                                                                                                                                         123
M. Lionello et al.




laryngeal squamous cell carcinoma (LSCC) 1. The purpose            Materials and methods
of partial laryngectomy is to ensure oncological radicality by
                                                                   Patients
completely removing the tumour while preserving laryngeal
                                                                   The present study concerned a cohort of 96 patients with
functions. The functional success of reconstructive laryn-
                                                                   glottic LSCC who underwent pre-operative radiological
gectomies is judged mainly from the rate of decannulation,
                                                                   staging with contrast-enhanced neck CT scans and subse-
which can only be achieved after breathing and swallowing
                                                                   quent supracricoid with/without suprahyoid epiglottis pres-
have fully recovered. The functional outcome after OPHL is
                                                                   ervation (OPHL type IIA/B) or supratracheal laryngectomy
good, with a reported 5-year laryngeal function preservation
                                                                   with/without suprahyoid epiglottis preservation (OPHL
rate of 97.8% for early-to-intermediate disease, and 91.2%
                                                                   type IIIA/B) 1 at Vittorio Veneto Hospital - Otolaryngology
for intermediate-to-advanced disease 2,3.
                                                                   Department from 2010 to 2016. According to the modular
Current contraindications to partial laryngectomy include
                                                                   OPHL approach, the open partial laryngectomy could be in-
alcohol and drug abuse, and major general comorbidities
                                                                   tra-operatively converted from supracricoid to supratrache-
(heart failure, lung diseases, diabetes mellitus, or severe
                                                                   al, in relation to results of frozen sections on surgical mar-
neurocognitive decline). Predictors of a poor functional out-
                                                                   gins 13. An attempt to occlude the tracheostomy with gauze
comes include: patient-related factors, such as very old age;
                                                                   was made as of the third post-operative day, depending on
and surgery-related factors, such as the type of procedure, i.e.
                                                                   the patients’ respiratory condition. All patients started with
supracricoid with/without suprahyoid epiglottis preservation
                                                                   the oral ingestion of water on the sixth post-operative day
(OPHL type IIA/B) or supratracheal laryngectomy with/with-
                                                                   with a trained speech therapist. If swallowing was satisfac-
out suprahyoid epiglottis preservation (OPHL type IIIA/B) 4,5.
                                                                   tory, the patient continued with semisolid and solid foods,
To the best of our knowledge, there are no pre-operative           otherwise they continued rehabilitation with gel water up to
radiological parameters known to predict functional out-           a satisfactory improvement. The nasogastric feeding tube
comes after OPHL. Identifying such prognostic indicators           (NFT) was kept in place until oral intake was satisfactory
would help laryngologists to choose the best treatment op-         (> 75%). Functional assessment of swallowing efficiency
tion for each patient, and provide appropriate pre-operative       with flexible endoscopy was performed in all patients with
counselling.                                                       persistent dysphagia (< 75% oral food intake) after 1 week
Conventional two-dimensional cephalometry has been                 of rehabilitation, or in case of complications, such as ab
used extensively in the fields of orthodontics and anthro-         ingestis pneumonia. Our OPHL patients currently remove
pology to record craniofacial dimensions. More recently, it        the tracheostomy tube during feeding and replace it after a
has also been applied to the evaluation of skeletal and aero-      meal. A percutaneous endoscopic gastrostomy (PEG) was
digestive tract anatomy in patients with obstructive sleep         considered in cases of persistent dysphagia at 3 weeks af-
apnoea syndrome (OSAS) 6-9. It has been claimed, how-              ter surgery or in case of ab ingestis pneumoniae. Patients
ever, that two-dimensional images cannot accurately reflect        could be discharged without a tracheostomy tube only after
three-dimensional (3D) aero-digestive tract anatomy 10,11.         breathing and swallowing had recovered adequately, with
Contrast-enhanced computerised tomography (CT) scan-               no significant aspiration. Failing this, they were discharged
ning of the neck is currently part of the diagnostic work-         with a tracheostomy tube in place, and outpatient re-as-
up and staging of patients with LSCC. CT imaging ena-              sessment was scheduled at one month. Patients’ clinical
bles linear measurements to be obtained, and volumes and           charts were retrospectively reviewed, considering the post-
cross-sectional areas of the aero-digestive tract can be cal-      operative decannulation and complication rates, length of
culated in three planes (coronal, sagittal, and axial). The        hospital stay, and need for a NFT.
axial plane, which is not visible on a lateral cephalogram, is
the most relevant physiologically because it is perpendicu-        Radiological assessment
lar to the air flow 12.                                            CT allows for precise measurements of cross-sectional areas
The primary endpoint of the present study was to inves-            on different levels, as well as three-dimensional reconstruc-
tigate the value of pre-operative cephalometric CT scan            tions and volumetric assessments 14. All LSCC patients at Vit-
parameters in predicting functional outcomes after OPHL,           torio Veneto Radiology Department underwent pre-operative
and decannulation rates at discharge in particular. Second-        contrast-enhanced neck CT. A volumetric axial CT scan was
ary endpoints were to analyse the value of other pre-oper-         performed with a 64-slice CT scanner (Revolution Evo, GE,
ative demographic and surgical parameters for the purpose          Milwaukee, WI) using a slide thickness of 1.25 mm (120 KV,
of predicting functional outcomes.                                 automatic modulating mA). Scout images (anterior and lateral



124
                                                                                                                             Cephalometry in OPHL




views) were obtained to ascertain the scanning area covered,
from the skull base to the mediastinum. Patients were placed
supine, with their head in a neutral position, and instructed to
remain still and avoid swallowing or coughing. Multiplanar
reformatted sagittal and coronal images were then generated
with a slice thickness of 0.6 mm, and the axial plane was re-
constructed with an orientation parallel to the true vocal cords
to better visualise the glottis. All scans were reworked and
analysed by the same experienced radiologist (C.C.). Once the
3D digital models had been constructed, the following cepha-
lometric parameters 11 were obtained (Fig. 1):
• volume (mL) of the aero-digestive tract from the base of the
   epiglottis to the hard palate (Vol);
• length (mm) from the base of the epiglottis to the hard pal-
   ate (L);
• minimum cross-sectional area (mm2) of the retroglossal
   aero-digestive tract from the base of the epiglottis to the
   inferior aspect of the soft palate (RG);
• minimum lateral dimension (mm) of cross section of the
   aero-digestive tract in the mid-retroglossal area (between
   the base of the epiglottis and the inferior aspect of the soft
   palate) (LAT);
• minimum antero-posterior dimension (mm) of cross sec-
   tion of the aero-digestive tract in the mid-retroglossal area
   (between the base of the epiglottis and the inferior aspect of
   the soft palate) (AP);
• distance (mm) between the genial tubercle and the hyoid
   bone in the mid-sagittal plane (GH).

Statistical analysis                                                Figure 1. Cephalometric parameters on CT scans. (A) length from hard palate
                                                                    to base of epiglottis (L); (B) distance from genial tubercle to hyoid bone in mid-
Correlations between demographic, surgical and cephalo-             sagittal plane (GH); (C) lateral dimension of cross section of aero-digestive tract
metric parameters and their functional outcomes were as-            in the mid-retroglossal area (between base of epiglottis and inferior aspect of soft
sessed using univariate (Fisher’s exact test) and multivari-        palate (LAT); antero-posterior dimension of cross section of aero-digestive tract
                                                                    in mid-retroglossal area (between base of epiglottis and inferior aspect of soft
ate (logistic regression) analyses. As functional outcomes          palate (AP); (D) volume of aero-digestive tract from base of epiglottis to hard pal-
we considered: i) decannulation at discharge (0/1); ii) time        ate (Vol); (E) cross-sectional area of retroglossal aero-digestive tract from base
to removal of the NFT (cut-off = 10 days); iii) post-opera-         of epiglottis to inferior aspect of soft palate (RG); (F) RG plane.
tive complication rate (0/1); and iv) length of hospital stay
(cut-off = 2 weeks).
The median values of NFT removal time and length of hos-            (25%) had supratracheal laryngectomy (OPHL type III).
pital stay (10 and 14 days, respectively), were considered          Twenty-four patients (25%) were discharged with a trache-
as cut off points for statistical analysis. A p-value < 0.05        ostomy cannula due to persistent dyspnoea or dysphagia,
was considered significant. The STATA™ statistical pack-            while 72 were decannulated after 7.2 ± 3.6 days (median 7
age (Stata Corp, College Station, TX, USA) was used for             days). The time to NFT removal was in the range of 6-35
all analyses.                                                       days (9.9 ± 4.0, median 9 days). A PEG was performed in 1
                                                                    patient who had undergone OPHL type III due to persistent
Results                                                             dysphagia. Thirty-three patients (34%) experienced at least
Among the cohort of 96 LSCC patients (88 males and 8 fe-            1 post-operative complication. The length of hospital stay
males; age range 28-80 years, median 62 years), 72 (75%)            ranged from 9 to 41 days (14.5 ± 4.8, median 13 days).
had a supracricoid laryngectomy (OPHL type II), and 24              Table I shows the results of the univariate analysis on the



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M. Lionello et al.




distribution of functional outcomes by demographic and                                post-operative laryngeal obstruction. Definitive decannula-
surgical parameters. The functional outcomes of patients                              tion was not possible in 5 cases because of persistent dysp-
who had OPHL type II as opposed to type III are explained                             noea. The NFT was removed after 11.0 ± 5.7 days. Sixteen
in detail below.                                                                      patients experienced at least 1 post-operative complication
                                                                                      (66%), involving: persistent dyspnoea in 11 cases; persis-
OPHL II patients                                                                      tent dysphagia in 5; ab ingestis pneumonia in 4; pharyn-
Seventy-two patients (age 28-71 years, median 63 years) un-                           go-cutaneous fistula in 1; and post-operative haemorrhage
derwent supracricoid laryngectomy, with conservation of the                           in one case. The hospital stay ranged from 10 to 41 days
suprahyoid epiglottis (OPHL type IIA) in 66 cases, while                              (mean 15.9 ± 6.2, median 15 days).
in 6 cases the epiglottis was completely removed (OPHL
type IIB). One arytenoid cartilage was sacrificed in 58 cases,                        Cephalometric parameters
while both cartilages were spared in 14 cases. Sixty-one pa-                          Analysing the 3D digital models for the whole cohort of
tients were decannulated after 7.2 ± 3.6 days (84%), while                            OPHL patients, the volume of the aero-digestive tract from
11 were discharged with the tracheostomy cannula still in                             the base of the epiglottis to the hard palate (Vol) was in
place. Seven of these patients were successfully decannu-                             the range of 8101 to 67698 mL (mean 29473.9 ± 12787.2,
lated at 6 months after transoral laser microsurgery to treat                         median 26589 mL). The length (mm) from the hard palate
post-operative laryngeal obstruction. Definitive decannula-                           to the base of the epiglottis (L) ranged from 45 to 98 mm
tion was not possible in 4 cases because of persistent dysp-                          (mean 72.7 ± 9.1, median 72 mm). The minimum cross-
noea. The NFT was removed after 3.5 ± 3.2 days. Thirteen                              sectional area of the retroglossal aero-digestive tract (RG)
patients experienced at least 1 post-operative complication                           ranged from 94 to 898 mm2 (mean 405.6 ± 167.5, median
(18%), involving: persistent dyspnoea in 12 cases; persistent                         367 mm2). The lateral dimension of the cross section of ae-
dysphagia in 3; ab ingestis pneumonia in 2; and a cervical                            ro-digestive tract in the mid-retroglossal area (LAT) ranged
abscess in one. The hospital stays for this group ranged from                         from 12 to 48 mm (mean 31.5 ± 7.4, median 32 mm). The
9 to 25 days (mean 14.0 ± 4.1, median 13 days).                                       antero-posterior dimension of the cross section of aero-di-
                                                                                      gestive tract in the mid-retroglossal area (AP) ranged from
OPHL III patients                                                                     6 to 26 mm (mean 16.1 ± 4.2, median 16 mm). The distance
Twenty-four patients (age 37-80 years, median 62 years)                               from the genial tubercle to the hyoid bone on the midsagit-
underwent supratracheal laryngectomy, with preservation                               tal plane (GH) ranged from 24 to 44 mm (mean 33.7 ± 4.9,
of the suprahyoid epiglottis (OPHL type IIIA) in 23 cases,                            median 34 mm). Table II shows detailed results of the mul-
and its complete removal (OPHL type IIIB) in one case.                                tivariate analysis for the distribution of functional outcomes
One crico-arytenoid unit (CAU) was sacrificed in 23 cases,                            by cephalometric parameters. In particular, we found that
while both were spared in one case. Eleven of the 24 pa-                              a larger GH significantly correlated with higher decannula-
tients were decannulated (45%) after 7.1 ± 3.8 days, while                            tion rate at discharge and shorter hospital stay (p = 0.045
13 were discharged with the tracheostomy cannula still in                             and p = 0.048 , respectively), and a greater AP was related
place. Eight of these patients were successfully decannu-                             to better functional outcomes in terms of decannulation rate
lated at 6 months after transoral laser microsurgery to treat                         at discharge (p = 0.021) (Fig. 2).




Table I. Results of the univariate analysis on the distribution of functional outcomes by demographic and surgical parameters.
 Parameter                    Tracheostomy            P         Hospital stay         P               NFT               P      Post-operative                   P
                                  cannula                         > 14 days                       > 10 days                    complications
                               at discharge
 Age (≥ 65 vs < 65 years)     33.3% vs 20%         0.154 47.2% vs 31.7%               0.136         47.2% vs 31.7%          0.136 47.2% vs 26.7% 0.034 *
 OPHL (III vs II)            54.2% vs 15.3% 0.000 54.2% vs 31.9% 0.045 *                            50.0% vs 33.3%          0.154 66.7% vs 23.6%              0.000
 OPHL (B vs A)               28.6% vs 24.7% 1.000 85.7% vs 33.7%                      0.011        85.7% vs 33.7%           0.011 14.3% vs 35.0%              0.416
 OPHL (+ 1 ary vs no ary) 13.3% vs 27.2% 0.343 60.0% vs 33.3% 0.049 *                               46.7% vs 35.8%          0.563 35.8% vs 26.7%              0.568
NFT: naso-gastric feeding tube; OPHL: open partial horizontal laryngectomy; OPHL type A: with preservation of the suprahyoid epiglottis; OPHL type B: without
preservation of the suprahyoid epiglottis; +1 ary: with sacrifice of 1 arytenoid cartilage; no ary: no sacrifice of arytenoid cartilages. P: Fisher’s exact test p value
(*: one sided).



126
                                                                                                                              Cephalometry in OPHL




  A
                                                                                   Discussion
                                                                                   Compared with conventional 2D cephalometry, 3D digital
                                                                                   models acquired with CT enable better assessment of the
                                                                                   cross-sectional dimensions of the aero-digestive tract 15.
                                                                                   Assessments of the upper aero-digestive tracts in 3D based
                                                                                   on CT scans have already been extensively described in
                                                                                   patients with OSAS 8. Ouyang et al. also used CT scans
                                                                                   to analyse anatomical changes after partial laryngectomies
                                                                                   such as vertical partial and supracricoid laryngectomies
                                                                                   that promoted the onset of post-operative OSAS 16. To the
                                                                                   best of our knowledge, the present study is the first to have
                                                                                   investigated the value of pre-operative cephalometric pa-
                                                                                   rameters acquired from CT scans in predicting functional
  B                                                                                outcomes after OPHL.
                                                                                   After conventional supracricoid laryngectomy with resec-
                                                                                   tion of the thyroid cartilage, the epiglottis or hyoid bone
                                                                                   are sutured directly to the cricoid cartilage, and the hyoid
                                                                                   bone is moved down, driving the base of the tongue back-
                                                                                   wards. The antero-posterior diameter of the cross-section
                                                                                   of aero-digestive tract in the mid-retroglossal area (AP) is
                                                                                   the narrowest dimension of the retrolingual space. Roden-
                                                                                   stein et al. found on CT scans that the tongue was displaced
                                                                                   backwards and downwards after OPHL type II; and they
                                                                                   reported that smaller AP dimensions correlated with more
                                                                                   severe post-OPHL OSAS 17. A similar concept may explain
                                                                                   the onset of persistent obstruction of the neoglottis as a
                                                                                   post-operative complication.
  C                                                                                In the present study, multivariate analysis showed that
                                                                                   larger AP and GH significantly correlated with better func-
                                                                                   tional outcomes in terms of decannulation rate at discharge
                                                                                   (p = 0.021, and 0.045, respectively). Patients with larger
                                                                                   Vol and RG also experienced better functional outcomes
                                                                                   (Tab. II), although the corresponding p-values were not sta-
                                                                                   tistically significant. A larger GH also correlated signifi-
                                                                                   cantly with a shorter hospital stay (p = 0.048). Patients with
                                                                                   a larger AP experienced lower complication rates as well
                                                                                   (Tab. II), although with no statistical significance. Taken to-
                                                                                   gether, our results show that patients whose upper aero-di-
                                                                                   gestive tracts are larger in diameter and volume have better
                                                                                   functional outcomes after OPHL. Since the most common
                                                                                   post-operative complication of such surgery is persistent
                                                                                   dyspnoea due to obstruction of the airway, a condition that
                                                                                   would hinder decannulation, the pre-operative finding of
Figure 2. Distributions of probabilities of decannulation at discharge by an-      low aero-digestive tract dimensions may reasonably predict
tero-posterior diameter of the cross-section of aero-digestive tract in the mid-   the functional success of the OPHL.
retroglossal area (A), and distances from the genial tubercle to the hyoid bone    When we considered demographic parameters, age at sur-
in the mid-sagittal plane (B) (p = 0.021, and 0.045, respectively). Distribution
of the probabilities of hospital stay > 14 days by distances from the genial tu-   gery correlated with functional outcomes, as reported else-
bercle to the hyoid bone in the mid-sagittal plane (C) (p = 0.048).                where 3. Our results confirmed that younger patients (< 65



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M. Lionello et al.




Table II. Relationships between cephalometric parameters and functional outcomes.
 Parameter                 Tracheostomy                        Hospital stay                                      NFT                           Post-operative
                        cannula at discharge                     > 14 days                                     > 10 days                        complications
                                 p (OR), CI                               p (OR), CI                           p (OR), CI                          p (OR), CI
 Vol                                 NS                                       NS                                  NS                                   NS
 L                                   NS                                       NS                                  NS                                   NS
 RG                                  NS                                       NS                                  NS                                   NS
 LAT                                 NS                                       NS                                  NS                                   NS
 AP                      0.021 (0.86), 0.76-0.97                              NS                                  NS                                   NS
 GH                      0.045 (0.90), 0.81-0.99                  0.048 (0.91), 0.83-0.99                         NS                                   NS
AP: antero-posterior dimension of cross section of the aero-digestive tract in the mid-retroglossal area between the base of the epiglottis and the inferior aspect of the
soft palate; GH: distance from the genial tubercle to the hyoid bone in the mid-sagittal plane; L: length from the hard palate to the base of the epiglottis; LAT: lateral
dimension of cross section of the aero-digestive tract in the mid-retroglossal area between the base of the epiglottis and the inferior aspect of the soft palate; NFT:
naso-gastric feeding tube; NS: not significant; RG: minimum cross-sectional area of the retroglossal aero-digestive tract from the base of the epiglottis to the inferior
aspect of the soft palate; Vol: volume of the aero-digestive tract from the base of the epiglottis to the hard palate; p (OR), CI: logistic regression p value (odds ratio),
confidence interval.


years old) have better functional outcomes, particularly in                             Probably the main limitation of the present study lies in the
terms of post-operative complications (p = 0.034) (Tab. I).                             relatively small cohort of OPHL patients (we only considered
It is generally agreed nowadays that functional recovery                                cases with pre-operative CT scans available). On the other
and response to post-operative rehabilitation are better in                             hand, one of its strengths concerns the homogeneity of the data
younger patients, in terms of both the timing and the per-                              (all the patients were operated and rehabilitated by the same
centage of this recovery.                                                               surgical team, and all CT scans were reworked and analysed
There is now ample evidence in the available literature on                              by the same radiologist). Further studies on larger cohorts of
the topic of the significant impact of the type of surgery on                           OPHL patients are nonetheless needed to confirm our findings.
the functional outcome. In a previous study, we found that
post-operative laryngeal obstruction (the most common                                   Conclusions
complication after partial laryngectomy) occurred in 11% of
                                                                                        Larger diameters and volumes of the upper aero-digestive
patients who had supracricoid laryngectomy (OPHL type II)
                                                                                        tracts correlated with better functional outcomes after
and 34% of those who had supratracheal laryngectomy
                                                                                        OPHL. In particular, the decannulation rate at discharge
(OPHL type III). OPHL type II coincided with a better func-
                                                                                        was higher, the larger the antero-posterior diameter of the
tional outcome than OPHL type III, in terms of decannula-
                                                                                        aero-digestive tract in the retroglossal area.
tion rate, time to tracheostomy closure and need for transoral
laser microsurgery to manage post-operative laryngeal ob-
                                                                                        Acknowledgements
struction 4. In a detailed comparison of functional outcomes
                                                                                        The authors thank Frances Coburn for correcting the English
after OPHL, Schindler et al. found that patients experienced
                                                                                        version of this paper. They also thank all the medical and par-
better vocal and swallowing results after OPHL type II than
                                                                                        amedical staff at the Otolaryngology Unit - Vittorio Veneto
after OPHL type III 5. The results of the present study con-
                                                                                        Hospital, for collecting the follow-up data, and the Associa-
firm as much: functional outcomes were worse after OPHL
                                                                                        tion “Amici della voce” (Friends of the Voice) for its support
type III than after OPHL type II, in terms of decannulation
                                                                                        in preparing the manuscript.
rate at discharge, hospital stay and post-operative complica-
tions (p = 0.000, p = 0.045, p = 0.000, respectively). Intui-                           Conflict of interest statement
tively, we can assume that sacrificing the epiglottis (OPHL                             The authors declare no conflict of interest.
type B) had a negative impact on the recovery of swallowing
function and length of hospital stay (p = 0.011 and p = 0.011,                          Funding
respectively). Similarly, the functional outcome was worse,                             This study was supported by a personal grant.
in terms of hospital stay (p = 0.049), after the removal of one
of the arytenoid cartilages, compared with cases in which                               Author contributions
both arytenoids were spared.                                                            ML: study design, data collection and elaboration, manuscript



128
                                                                                                                            Cephalometry in OPHL




writing and editing; CC, CV: data collection; LF: statistical             7    Cheng CF, Peng CL, Chiou HY, et al. Dentofacial morphol-
analysis; SG, GP, PN, AB: paper review.                                        ogy and tongue function during swallowing. Am J Orthod
                                                                               Dentofacial Orthop 2002;122:491-499. https://doi.org/10.1067/
                                                                               mod.2002.128865
Ethical consideration                                                     8    Abramson Z, Susarla S, August M, et al. Three-dimensional com-
This study was approved by the Institutional Ethics Commit-                    puted tomographic analysis of airway anatomy in patients with
tee (Nucleo Ricerca Clinica – Servizio Farmaceutico Azien-                     obstructive sleep apnea. J Oral Maxillofac Surg 2010;68:354-362.
dale – approval protocol number 19881).                                        https://doi.org/10.1016/j.joms.2009.09.087
The research was conducted ethically, with all study proce-               9    Denolf PL, Vanderveken OM, Marklund ME, et al. The status of
                                                                               cephalometry in the prediction of non-CPAP treatment outcome
dures being performed in accordance with the requirements
                                                                               in obstructive sleep apnea patients. Sleep Med Rev 2016;27:56-
of the World Medical Association’s Declaration of Helsinki.                    73. https://doi.org/10.1016/j.smrv.2015.05.009
Written informed consent was obtained from each participant/              10   Cattaneo C. Forensic anthropology: developments of a classical
patient for study participation and data publication.                          discipline in the new millennium. Forensic Sci Int 2007;165:185-
                                                                               193. https://doi.org/10.1016/j.forsciint.2006.05.018
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