Superior Constrictor Research Articles

Prediction of Requirement of Artificial Nutrition by Dosimetric and Clinical Factors in Head-and-Neck Cancer Patients

Purpose/Objective(s): Intensification of radiation therapy and chemotherapy for head-and-neck cancer may leads to increased rates of acute and long term dysphagia as a severe side effect. Artificial nutrition is frequently required during and after radiation therapy and chemoradiation. Several dosimetric and clinical factors were analyzed to identify the most relevant factors being able to predict the necessity of artificial nutrition during radiation therapy of head and neck cancer patients. Materials/Methods: From an institutional database, 101 patients (72 male, 29 female, mean age 59.5 years) were identified who underwent definitive or adjuvant radiation therapy or chemoradiation for head and necks cancer. Clinical factors (ECOG performance status, age, gender, BMI, chemotherapy, TNM stage) and several dosimetric parameters (amongst others: oropharynx + 1 cm, superior pharyngeal constrictor muscle, larynx, oral cavity) were evaluated by using a multiple logistic regression model for their predictive value regarding the need for artificial nutrition for more than 5 days during radiation therapy. Results: Whereas several clinical and dosimetric factors were significantly associated with the need for artificial nutrition in the univariate analysis, in the multivariate analysis, only the mean dose to the oropharynx + 1 cm (p Z 0.006), ECOG (0-1 vs 2-4) [p Z 0.04] and of chemotherapy (yes/no) [p Z 0.04] remained significant. Conclusions: Using a 3 parameter model we were able to distinguish patients with different risk factors (10-70%) for the need for artificial nutrition, which could be helpful to decide which patients need prophylactic PEG. Author Disclosure: E. Boelke: None. C. Matuschek: None. C. Geigis: None. K. Scheckenbach: None. T. Hoffmann: None. J. Greve: None. W. Budach: None.

Transoral anatomy of the tonsillar fossa and lateral pharyngeal wall: Anatomic dissection with radiographic and clinical correlation

To evaluate the transoral anatomy of the tonsillar fossa and lateral pharyngeal wall and to correlate these findings with radiographic measurements and transoral robotic surgery (TORS) of patients with early tonsillar tumor. Preclinical cadaveric study and patient cohort. Six complete cadaveric dissections were performed to identify key anatomic landmarks, and these landmarks were validated in two consecutive patients with T1 human papillomavirus-positive squamous cell carcinoma of the tonsil treated by TORS. For radiographic landmark analysis, 25 patients who underwent contrast-enhanced computed tomography (CT) of the neck for a variety of endoscopic skull base procedures were selected. Measurements were taken from the lateral pharyngeal wall at C2-C3 interspace and greater horn of hyoid (C6) to the external carotid artery (ECA). The glossopharyngeal (IX) nerve was consistently identified deep to the superior constrictor musculature and at the intersection of the posterior tonsillar pillar with the base of tongue. The styloglossus muscle forms the deep plane medial to the ECA. The mean measurements for left C2-C3 interspace to the ECA and right C2-C3 interspace to ECA were 17.6 ± 0.8 mm and 18.4 ± 0.8 mm, respectively. Similarly, the mean measurements for left hyoid to ECA and right hyoid to ECA were 3.4 ± 0.8 mm and 4.3 ± 0.6 mm, respectively. A systematic approach to dissect the tonsillar fossa and lateral pharyngeal wall can be performed using key anatomic landmarks. CT measurements taken at the C2-C3 interspace and greater horn of hyoid bone (C6 level) to the ECA are consistently and reliably achieved.

Predictors of PEG dependence after IMRT ± chemotherapy for oropharyngeal cancer

PurposeTo prospectively assess predictors of PEG dependence after IMRT with/without concomitant chemotherapy (CHT). Methods and materialsOne-hundred-seventy-one patients were considered (exclusive RT: 58, RT+CHT: 113; 159/171 treated at a median dose of 70Gy, 2Gy/fr). Patients treated with RT+CHT underwent prophylactic PEG insertion; PEG was as needed for the others. A number of clinical factors and dose–volume information concerning oral mucosa (OM), constrictors, masticatory muscles, larynx, esophagus and parotids were available. The 25th/10th percentiles of the duration of PEG dependence were our end-points (respectively 3.3 and 7months, PEG3/PEG7). Logistic uni and multi-variate (MVA) analyses were performed. ResultsConcerning PEG3, the independent predictors at MVA were: CHT/PEG policy (OR: 6.8, p=0.001), V9.5G_OMGy/week (OR: 1.017, p=0.01), larynx V50 (OR: 1.018, p=0.01) and superior constrictor (SC) D_mean (OR: 1.002, p=0.005); the predictive value of the model (AUC) was 0.818 (95% CI: 0.751–0.873). The independent predictors of PEG7 were: larynx V50 (OR: 1.042, p=0.0005) and SC D_mean (OR: 1.003, p=0.02), symptoms at diagnosis (yes vs no, OR: 3.6, p=0.08) and sex (male vs female, OR: 0.25, p=0.07); AUC was 0.897 (95% CI: 0.841–0.939). ConclusionsOM V9.5Gy/week and CHT/PEG_policy modulate the risk of early PEG dependence. For longer PEG dependence, larynx V50 (or D_mean) and SC D_mean are highly predictive, suggesting that the fibrosis of constrictors and larynx is the main cause.

A predictive model for dysphagia following IMRT for head and neck cancer: Introduction of the EMLasso technique

Background and purposeDesign a model for prediction of acute dysphagia following intensity-modulated radiotherapy (IMRT) for head and neck cancer. Illustrate the use of the EMLasso technique for model selection. Material and methodsRadiation-induced dysphagia was scored using CTCAE v.3.0 in 189 head and neck cancer patients. Clinical data (gender, age, nicotine and alcohol use, diabetes, tumor location), treatment parameters (chemotherapy, surgery involving the primary tumor, lymph node dissection, overall treatment time), dosimetric parameters (doses delivered to pharyngeal constrictor (PC) muscles and esophagus) and 19 genetic polymorphisms were used in model building. The predicting model was achieved by EMLasso, i.e. an EM algorithm to account for missing values, applied to penalized logistic regression, which allows for variable selection by tuning the penalization parameter through crossvalidation on AUC, thus avoiding overfitting. ResultsFifty-three patients (28%) developed acute⩾grade 3 dysphagia. The final model has an AUC of 0.71 and contains concurrent chemotherapy, D2 to the superior PC and the rs3213245 (XRCC1) polymorphism. The model’s false negative rate and false positive rate in the optimal operation point on the ROC curve are 21% and 49%, respectively. ConclusionsThis study demonstrated the utility of the EMLasso technique for model selection in predictive radiogenetics.

Choking on a grape: an unusual type of upper airway obstruction

ForewordBradwell, a London doctor, stated in 1663 ‘‘Of things thatendanger stopping of the breath in swallowing, some aresharp, and some blunt… I have heard of a child inWoodstreet strangled with a grape.’’ [1, 2]Case reportAfter a mother had fed a 4-year-old boy a grape he sud-denly became ‘‘blue in the face’’ and started to ‘‘wheeze.’’The boy died about 1 h from the original onset of symp-toms, on his way to hospital. During the autopsy the nextday the non-chewed grape was found wedged between theanterior side of the epiglottis and the upper side of the rootof the tongue, caught between the median glosso-epiglotticfold and the tonsils (Figs. 1, 2). In this position the grapepressed on the epiglottis, pushing it backwards toward thelaryngeal inlet, obstructing it completely. There were noinjuries to the oral, pharyngeal, or laryngeal mucosae.Pleural petechial hemorrhages, congestion, and tissueswelling, as well the fluidity of the blood were noted duringthe autopsy. The cause of death was choking by obstructionof the upper airway by a non-chewed grape.DiscussionChoking refers to blockage of the internal airways, usuallybetween the pharynx and the bifurcation of the trachea.Causes of choking include metallic, plastic, or other for-eign bodies, food material, as well as acute obstructivelesions—edema of the glottis or larynx [3]. Long-standingbenign tumors or other conditions could also compromisethe upper respiratory tract, causing choking [4–6].In adult cases, the most common cause of laryngealobstruction is by a bolus of food, that is, a ‘‘cafe coronary.’’The term was first used by Haugen in 1963 for sudden andunexpected death occurring during a meal because of theaccidental occlusion of the airway by a bolus of food [7].Choking and obstruction of the trachea or main bronchi byaspiration of a foreign body is a common cause of acci-dental death in children aged from 1 to 5 years, that is, a‘‘creche coronary’’ [1, 2, 8]: more than 90 % of cases occurin infants and children younger than 5 years, with 65 % ininfants younger than 2 years [1]. Round foods are the mostfrequently aspirated foreign objects causing death [2]. Thephases of acute fatal airway obstruction are entrance of theobject into the airway, obstruction of the airway, andfailure to expel once obstruction has occurred [8].The case presented in this paper could indicate anotherpossible mechanism of upper airway obstruction in cases ofchoking, beside penetration of the object into the airway.During the first oropharyngeal phase of swallowing, thefood-bolus is forced by the tongue posteriorly toward thepharynx, as the tongue pushes upward against the hardpalate. The superior constrictor muscle of the pharynx thencontracts, preventing the movement of bolus into thenasopharynx. At the same time, the epiglottis slidesdownward to prevent the bolus from entering the larynxand the trachea [9]. Hence, it is easy to presume that a

Dysphagia and trismus after concomitant chemo-Intensity-Modulated Radiation Therapy (chemo-IMRT) in advanced head and neck cancer; dose–effect relationships for swallowing and mastication structures

Background and purposeProspective assessment of dysphagia and trismus in chemo-IMRT head and neck cancer patients in relation to dose-parameters of structures involved in swallowing and mastication. Material and methodsAssessment of 55 patients before, 10-weeks (N=49) and 1-year post-treatment (N=37). Calculation of dose–volume parameters for swallowing (inferior (IC), middle (MC), and superior constrictors (SC)), and mastication structures (e.g. masseter). Investigation of relationships between dose-parameters and endpoints for swallowing problems (videofluoroscopy-based laryngeal Penetration-Aspiration Scale (PAS), and study-specific structured questionnaire) and limited mouth-opening (measurements and questionnaire), taking into account baseline scores. ResultsAt 10-weeks, volume of IC receiving ⩾60Gy (V60) and mean dose IC were significant predictors for PAS. One-year post-treatment, reported problems with swallowing solids were significantly related to masseter dose-parameters (mean, V20, V40 and V60) and an inverse relationship (lower dose related to a higher probability) was observed for V60 of the IC. Dose-parameters of masseter and pterygoid muscles were significant predictors of trismus at 10-weeks (mean, V20, and V40). At 1-year, dose-parameters of all mastication structures were strong predictors for subjective mouth-opening problems (mean, max, V20, V40, and V60). ConclusionsDose–effect relationships exist for dysphagia and trismus. Therefore treatment plans should be optimized to avoid these side effects.

A ganglion cell cluster along the glossopharyngeal nerve near the human palatine tonsil

Conclusion: The lingual branches of the glossopharyngeal nerve were most likely to bring not only gustatory nerves to the postsulcal part of the tongue but also autonomic nerves to the small glands and vessels. Tonsillectomy may injure the ganglion or reduce its function due to scar formation after surgery. Objectives: To determine the topographical anatomy of a suggested ganglion cluster along the lingual branches of the glossopharyngeal nerve and to identify the incidence. Methods: In the human pharynges of 12 donated cadavers, we studied the ganglia using routine procedures for paraffin-embedded histology and immunohistochemistry. Results: Near the palatine tonsil, the lingual branches of the glossopharyngeal nerve often contained ganglion cells (in 9 of 12 specimens). The ganglion cells, 20–40 µ in diameter, were sparsely distributed along a 0.5–3.0 mm length of the nerve course attached to the posterolateral aspect of the superior pharyngeal constrictor. Most of these cells were positive for neuronal nitric oxide synthase, while some were positive for tyrosine hydroxylase. Thus, the ganglion was composed of a mixed population of sympathetic and parasympathetic neurons.

Reducing posttreatment dysphagia: Support for the relationship between radiation dose to the pharyngeal constrictors and swallowing outcomes

PurposeThis study used prospective swallowing data to establish the following: (1) whether doses to the pharyngeal constrictor muscles (PCMs) were significantly associated with swallowing outcomes; and (2) a mean dose constraint to aim for in intensity modulated radiation therapy planning. Methods and MaterialsThe PCMs were contoured and radiation dose data obtained for 55 patients with head and neck cancer. Associations between radiation dose and percentage of pharyngeal residue, penetration-aspiration and activity limitation measured at 6 months posttreatment were analyzed. Pretreatment swallowing function, tumor site, T classification, and chemotherapy were accounted for in multivariate analyses. ResultsOn multivariate analysis, the percentage of pharyngeal residue was statistically significantly associated with the mean dose to the superior PCM (95% confidence interval [CI], 0.15-1.66; P = .02). Penetration-aspiration was associated with the mean dose to the superior, middle, and inferior PCMs (95% CI, 1.02-1.27; P = .003; 95% CI, 1.02-1.23; P = .003; 95% CI, 1.04-1.21; P = .003, respectively) and the mean dose to the total PCM (95% CI, 1.05-1.31; P = .001). Activity limitation was also associated with the mean dose to the superior, middle, and inferior PCMs (95% CI, 1.01-1.20; P = .02; 95% CI, 1.00-1.15; P =.04; 95% CI, 1.01-1.15; P = .02, respectively) and the mean dose to the total PCM (95% CI, 1.02-1.23; P = .01). On univariate analysis, all 3 swallowing measures were statistically significantly worse for patients who received a biologically equivalent mean dose of >60 Gy to the PCMs. This remained significant on multivariate analysis for both penetration-aspiration and activity limitation (95% CI, 2.05-58.2, P = .004 and 95% CI, 1.14-27.7, P = .03, respectively). ConclusionsThe radiation dose to the PCMs is significantly associated with swallowing dysfunction. Limiting the mean PCM dose to less than 60 Gy results in better swallowing outcomes.

Extent of local invasion and safe resection in cT1–2 tonsil cancer

Although intraoral resection of small-sized tonsil cancer achieves excellent tumor control, the extent of local invasion and adequate safety margin in resection have not been studied. Thus, we aim to determine the extent of local invasion in terms of mucosal spread and deep infiltration in stage T1-2 tonsil cancer. We re-analyzed the surgical specimens from 49 cT1-2 tonsil cancers. Microscopic tumor cell extension from the tumor gross boundary of specimens was assessed in representative sections of each tumor. We also tested whether local extension correlates with human papilloma virus (HPV) status of tumors. The extent of microscopic deep invasion from the gross tumor border was 0.52 ± 0.41 mm, which was significantly less than that of mucosal spread (0.83 ± 0.61 mm, P = 0.01) in cT1-2 tonsil cancer. The microscopic deep invasion correlated with tumor size (rho = 0.703, P < 0.001). We found tumor invasion into superior constrictor muscles in 58.1%, no cases of tumor invasion into the deep fascia. In terms of HPV status (genotyping plus p16 staining), there were no differences in microscopic tumor extension. Our detailed pathologic analyses confirm that an oropharyngectomy including the superior constrictor muscle is an oncologically safe procedure for stage T1-2 tonsil cancer.

Evolution of swallowing in lateral pharyngoplasty with stylopharyngeal muscle preservation

Lateral pharyngoplasty manages obstructive sleep apnea through the myotomy and repositioning of the muscles of the lateral pharyngeal wall. Dysphagia after any pharyngeal surgery is influenced by pain, discomfort from the sutures, the healing process and by the adaptation to the changes in pharyngeal structures. Experience with lateral pharyngoplasty has shown that the superior pharyngeal constrictor muscle plays a minor role in swallowing. One of them, the stylopharyngeus muscle, seems to play an important role during swallowing. ObjectiveThe aim of this study is to provide a daily analysis of the follow-up of the swallowing function. MethodWe have prospectively evaluated the swallowing function in 20 patients, through the daily application of a visual analogue scale from the first post-op until the complete disappearance of dysphagia. ResultsPatients have returned to their normal feeding habits in a mean of 10.9 days after the procedures and they presented a completely normal swallowing, on average, 21.6 days after the surgeries. All patients recover normal swallowing after the procedures, with a maximum recovery time of 33 days. ConclusionIn this study, all patients who underwent lateral pharyngoplasty with total preservation of the stylopharyngeus muscle reported complete normalization of swallowing with a recovery time up to 33 days.

Endoscopic endonasal anatomy of the nasopharynx in a cadaver model

Nasopharyngectomy is an accepted treatment for recurrent nasopharyngeal carcinoma following radiation with or without chemotherapy. Traditionally, the nasopharynx has been approached through relatively invasive "open" techniques including transpalatal, maxillary swing, and trans-mandibular-pterygoid approaches. Contemporary management has included the use of endoscopic techniques to exenterate tumors in this location. The purpose of the present study is to describe the endoscopic anatomy of this region through cadaveric dissection and to characterize the technical limitations of the approach. Five fresh cadaveric heads were dissected to study the endoscopic anatomy of the nasopharynx and associated structures. Endoscopic dissection of the nasopharynx was completed in all 5 specimens. Nasopharyngeal anatomy including the buccopharyngeal fascia, pharyngobasilar fascia, superior constrictor, longus capitus, longus coli, fossa of Rosenmuller, basisphenoid, auditory torus, and internal carotid artery were characterized. Surgical access to the nasopharynx has posed significant challenges in the treatment of recurrent or persistent nasopharyngeal carcinoma. This study demonstrated that endoscopic dissection of this region is feasible and has the potential to completely exenterate these lesions.

Clinical Features of Peritonsillar Abscess in Children

Peritonsillar abscess is an acute infection located between the capsule of the palatine tonsil and the superior constrictor muscle of the pharynx. The reports regarding pediatric cases have been scanty. A retrospective study was conducted to investigate the patients less than 18 years of age hospitalized at a medical center with a final diagnosis of peritonsillar abscess from January 1999 through December 2009. Only those who were confirmed by the drainage of pus from the peritonsillar spaces or confirmed by a computed tomography (CT) scan were enrolled. In total, 56 children, 31 male and 25 female, were included. The mean age was 12.9 ± 4.6 years, ranging from 9 months to 17.9 years. Nineteen (34%) were less than 12 years of age. All 37 children ≧12 years of age complained of sore throat, but only 68% of children less than 12 years of age complained of sore throat. Thirty-one patients (55%) with a characteristic presentation of fever and sore throat plus an asymmetric swollen/bulging tonsil with or without uvular deviation suggestive of the diagnosis received surgical drainage at emergency department immediately, and 87% of them were older than 12 years of age. Twenty-five (45%) children needed a CT scan to confirm the diagnosis. The most common empirical antibiotics were penicillin-containing regimens. The predominant organisms identified were Streptococcus species. Eight children were treated successfully with antibiotics alone. No case was fatal. Two-thirds of the children with peritonsillar abscess were ≥12 years of age. Not every patient <12 years of age had a characteristic presentation, and a CT scan was usually needed to confirm the diagnosis.

Bilateral lingual nerve injury associated with classic laryngeal mask airway

Editor, A 36-year-old American Society of Anesthesiologists physical status Class I woman underwent a myomectomy for uterine fibroid. A size 4 classic laryngeal mask airway (LMA) was easily and atraumatically inserted and cuff inflated. Positive pressure ventilation started with no detectable air leak. Anaesthesia was maintained with sevoflurane 2–3% in O2/air. Procedure was prolonged due to surgical difficulties and intraoperative bleeding to a total time of 180 min. In recovery, patient reported tongue numbness and abnormal taste sensation over the anterior two thirds of the tongue. No obvious swelling, haematoma or bleeding in the oral cavity was noticed. After 3 weeks, she felt that 90% of the tongue sensation had returned to normal. It took 6 weeks for complete resolution of her symptoms; a diagnosis of lingual nerve damage was made based on the clinical presentation and relevant clinical examination. Patient consent was obtained for publication of this case report. Lingual nerve is a branch of the third division of the trigeminal nerve; it carries taste fibres from the facial nerve, namely the chorda tympani, supplying the anterior two thirds of the tongue. During its course, it lies in close proximity to the mandible, making it vulnerable to compression and damage. Injury could present with varying symptoms of neuropathic pain.1 Several reports of cranial nerve damage (lingual, hypoglossal and recurrent laryngeal nerve)2 as well as submandibular and parotid gland swellings3 have been published. The majority are related to the classic LMA, a few are related to ProSeal LMA. The mechanism of injury to the lingual nerve has been described before as a pressure neuropraxia when it enters the oral cavity below the inferior border of the superior constrictor muscle. Potential predisposing factors include traumatic insertion, high cuff pressures, use of small-size LMA, use of nitrous oxide, malpositioning including lateral position and extreme head-side rotation. Small-size LMA and the use of nitrous oxide were a common factor in most of the cases. Nitrous oxide diffuses into the cuff, leading to an increase in its pressure. This is likely to build up with time. Anaesthetists should be vigilant in monitoring cuff pressures during the procedure if nitrous oxide to be used. The classic LMA should be inflated according to manufacturer's guidelines using a volume-controlled technique aiming to achieve an adequate seal and avoiding intracuff pressure above 60 cmH2O. In this case, the only indeterminate was cuff pressure. If a manometer is not readily available, the use of a 10-ml syringe connected to the pilot balloon and allowed to equilibrate could give a good estimate of correct cuff pressure.4 To avoid nerve damage, the following conditions must be considered: Use the appropriate size LMA for the case, 4 for women and 5 for men. Gentle airway manipulation. Avoid cuff pressure above 60 cmH2O. Ensure cuff pressure measurement every 30 min, if using nitrous oxide. Avoid extreme neck positions. Have a low threshold of suspicion for lingual nerve damage if patient reports abnormal sensation/taste. What to do if it happens: Early referral to a specialist is required. Tests for light touch, pin prick and two-point discrimination could be used to identify the baseline and monitor progress. Clear documentation of patient complaints and clinical findings helped with schematic illustration to the areas of damage for further assessment and follow-up. If problems of neuropathic pain are encountered, a referral to a pain specialist might be required. In summary, cranial nerve damage related to the use of supraglottic airway devices is a rare but well described occurrence. Despite avoiding all known risk factors damage may still occur. We cannot overemphasis the need for cuff pressure measurement by some validated means. Close monitoring for improvement is vital, as without signs of improvement early intervention is essential. Acknowledgements The authors would like to declare that they have not received any assistance, financial support or sponsorship in relation to above publication and have no conflicts of interest.

PO-0715 VARIABILITY OF NTCP PREDICTION OF SWALLOWING ORGANS AT RISK, DUE TO VARIATION IN DELINEATION GUIDELINES

Purpose/Objective: In daily practice, several different delineation guidelines can be used for the delineation of organs at risk that are involved in swallowing (SWOARs). Based on these delineation guidelines, predictive models have been developed for the different aspects of post treatment swallowing dysfunction. This study was performed to test the hypothesis that different guidelines result in different delineated SWOARs and subsequently different NTCP values for swallowing dysfunction. Materials and Methods: Thirty head and neck cancer patients with either laryngeal or pharyngeal carcinoma, treated with swallowing sparing IMRT, were included in this study. Nine SWOAR delineation guidelines derived from literature were compared. The following SWOARs were investigated: superior pharyngeal constrictor muscles (PCM), middle PCM, supraglottic larynx and esophageal inlet muscle (EIM). Especially, differences in description, geometric measures (centre of mass and coefficients of variance for volume), and resulting SWOAR dose-volume parameters were investigated. The results were used to examine the variation in the prediction of normal tissue complication probability (NTCP). For this comparison, five NTCP models for swallowing dysfunction from literature were used with the following endpoints: (1) RTOG grade 2-4; (2) problems with swallowing solid, (3) soft, and (4) liquid food; (5) choking when swallowing. Results: The description of the posterior and anterior borders of the SWOARs in the delineation atlases was similar. However, differences up to several centimeters were seen in the description of the cranial and caudal borders of some of the SWOARs. Mean differences in the position of the centre of mass in cranio-caudal direction were largest for the EIM and superior PCM: 2.2 cm ± 0.4 cm and -1.2 cm ± 0.6 cm respectively. Coefficients of variance of the volume of the SWOARs were largest for the EIM and for the middle PCM: 80% and 45% respectively. The range in differences in NTCP value per tumor location for all models was 0.1 - 18% for oropharynx (18% for endpoint 2), 0.00 - 22.4% for larynx (22.4% for endpoint 5), 0.04 - 7.7% for nasopharynx (7.7% for endpoint 5), 0.20 - 11.7% for hypopharynx (11.7% for endpoint 5), and 0.04 - 1.7% for oral cavity (1.7% for endpoint 2). Thus largest variations were found for tumors situated in the larynx and for NTCP model 'Choking when swallowing' (see figure). (Figure presented). Conclusions: Large variations in the definition of SWOARs were found among published delineation guidelines. This caused considerable variation in delineated volumes and in the position of the SWOARs which in turn resulted in different dose-volume values, and in different NTCP values. Therefore, an NTCP model from a specific group should only be used when SWOARs are delineated according to the corresponding delineation guidelines. Moreover, formulation of generally accepted guidelines for swallowing structures is strongly recommended to improve the generalisability of NTCP models.

Fat Injections for the Treatment of Velopharyngeal Insufficiency

The aim of this article was to describe the technical details of a fat injection procedure for the treatment of mild to moderate velopharyngeal insufficiency (VPI). Before surgery, the velopharyngeal gap is assessed by means of flexible nasoendoscopy, and speech intelligibility, hypernasality, and nasal air escape are perceptually evaluated and scored by independent raters; nasal airflow during speech is objectively measured. The lipoaspirate is centrifuged at 1200g for 3 minutes to separate and remove blood, cell debris, and the oily layer. Patients are injected with 3.5 to 8 mL of fat in the posterior and lateral pharyngeal walls and soft palate under general anesthesia. The fat is placed within the superior constrictor muscle on the posterior pharyngeal wall to avoid injection behind the prevertebral fascia and possible intraoperative or postoperative fat displacement in a caudal direction. A 19-gauge malleable, blunt, single-hole cannula is used for fat grafting, and the operative field is exposed by means of a Digman mouth gag. Two Nelaton probes are inserted through the nostrils and retracted from the mouth under moderate tension to favor visualization of the nasopharynx. No donor-site or injection-site morbidity has been observed so far, and the 12 patients (aged 5-48 y) treated so far have not manifested snoring or nasal obstruction at any time after surgery. Improved voice resonance is audible soon after the operation, and no hyponasality can be detected. The patients are discharged the day after surgery. Subsequent fat grafting procedures can be performed to achieve further improvement. Correctly performed fat injections improve voice resonance and reduce nasal air escape in VPI, as demonstrated by nasoendoscopy, speech perceptual evaluation, and the objective measurement of nasal airflow and represent an alternative to velopharyngoplasty for mild to moderate VPI.

Peritonsillar Infections: Prospective Study of 100 Consecutive Cases

IntroductionPeritonsillar infection is the most frequent complication of acute tonsillitis. Peritonsillar infections are collections of purulent material, usually located between the tonsillar capsule and the superior constrictor of the pharynx. Peritonsillar infection can be divided into abscess and cellulitis. Material and methodsWe prospectively analysed the clinical data from 100 patients with peritonsillar infection from 2008 to 2010. The diagnosis of abscess or peritonsillar cellulitis was primarily based on obtaining pus through fine-needle aspiration. ResultsSeventy-seven percent of patients had no history of recurrent tonsillitis and 55% were receiving antibiotic treatment. Sixty-two cases were peritonsillar abscess and the rest were cellulitis. Trismus, uvular deviation and anterior pillar bulging were statistically associated with peritonsillar abscess (P<.005). All patients were admitted to hospital and treated with puncture-drainage, intravenous antibiotics (amoxicillin/clavulanate in 83% of cases) and a single dose of steroids. All patients were discharged on oral antibiotic therapy. The mean length of hospital stay was 3 days and the recurrence rate was 5%. ConclusionsDue to the absence of clinical practice guidelines, there are different therapeutic protocols. According to our experience, puncture-aspiration and administration of intravenous antibiotics is a safe, effective way to treat these patients. To determine the efficacy and safety of outpatient management, controlled studies would be needed.

Newly identified thin membranous tissue in the deep infratemporal region

Recently, the importance of deglutition has attracted attention due to its role in the prevention of aspiration pneumonia. We therefore observed the anatomy of the pharynx of 57 hemi-sections of adult Japanese cadavers (male 32 sides, female 25 sides). A previously unidentified tissue was observed in the infratemporal fossa. This unidentified tissue was a thin membranous tissue that existed between the medial pterygoid and the superior constrictor in all of the cadavers examined. The previously unknown membranous tissue consisted of collagenous and muscular fibers and was innervated mainly by a branch of the mandibular nerve.

The Extracellular Matrix of the Lateral Pharyngeal Wall in Obstructive Sleep Apnea

To compare the components of the extracellular matrix in the lateral pharyngeal muscular wall in patients with and without obstructive sleep apnea (OSA). This may help to explain the origin of the increased collapsibility of the pharynx in patients with OSA. Specimens from the superior pharyngeal constrictor muscle, obtained during pharyngeal surgeries, were evaluated using histochemical and immunohistochemical analyses to determine the fractional area of collagen types I and III, elastic fibers, versican, fibronectin, and matrix metalloproteinases 1 and 2 in the endomysium. Academic tertiary center. PATIENS: A total of 51 nonobese adult patients, divided into 38 patients with OSA and 13 nonsnoring control subjects without OSA. Postintervention study performed on tissues from patients after elective surgery. Pharyngeal muscles of patients with OSA had significantly more collagen type I than pharyngeal muscles in control subjects. Collagen type I was correlated positively and independently with age. The other tested components of the extracellular matrix did not differ significantly between groups. In a logistic regression, an additive effect of both the increase of collagen type I and the increase in age with the presence of OSA was observed (odds ratio (OR), 2.06; 95% confidence interval (CI), 1.17-3.63), when compared with the effect of increased age alone (OR, 1.11; 95% CI, 1.03-1.20). Collagen type I in the superior pharyngeal constrictor muscle was more prevalent in patients with OSA and also increased with age. It was hypothesized that this increase could delay contractile-relaxant responses in the superior pharyngeal constrictor muscle at the expiratory-inspiratory phase transition, thus increasing pharyngeal collapsibility.

Peritonsillar abscess after tonsillectomy

We enjoyed reading the comprehensive review by Farmer et al on the subject of peritonsillar abscesses following tonsillectomy. We would, however, like to draw attention to the precise nature and terminology used when referring to such abscesses. It is our experience that patients may develop an abscess in a similar position to a peritonsillar abscess after a tonsillectomy. This may actually occur deep and lateral to the superior constrictor muscle as opposed to between the superior constrictor and any remaining fibrous tonsil capsule tissue. In this way, the patient will indeed present with odynophagia, trismus, systemic malaise with pyrexia and a ‘hot potato voice'. On examination, there will be swelling in the lateral pharynx causing medialisation of the tissues including the uvula. This is a separate entity from a collection where there is remaining tonsil tissue that remains a peritonsillar abscess. In cases where there is no tonsillar tissue, however, this may represent a parapharyngeal abscess and should be managed as such. In the ten papers reviewed, six patients were managed with incision and drainage. It is our practice to obtain cross-sectional imaging with computed tomography of the oropharynx and neck to delineate the extent of the collection and to proceed with incision and drainage under general anaesthesia. The patient should be observed for any evidence of tracking infection as with any parapharyngeal abscess and treated with intravenous antibiotics such as benzylpenicillin and metronidazole.

Infecciones periamigdalinas: estudio prospectivo de 100 casos consecutivos

IntroductionPeritonsillar infection is the most frequent complication of acute tonsillitis. Peritonsillar infections are collections of purulent material, usually located between the tonsillar capsule and the superior constrictor of the pharynx. Peritonsillar infection can be divided into abscess and cellulitis. Material and methodsWe prospectively analysed the clinical data from 100 patients with peritonsillar infection from 2008 to 2010. The diagnosis of abscess or peritonsillar cellulitis was primarily based on obtaining pus through fine-needle aspiration. ResultsSeventy-seven per cent of patients had no history of recurrent tonsillitis and 55% were receiving antibiotic treatment. Sixty-two cases were peritonsillar abscess and the rest were cellulitis. Trismus, uvular deviation and anterior pillar bulging were statistically associated with peritonsillar abscess (P<.005). All patients were admitted to hospital and treated with puncture-drainage, intravenous antibiotics (amoxicillin/clavulanate in 83% of cases) and a single dose of steroids. All patients were discharged on oral antibiotic therapy. The mean length of hospital stay was 3 days and the recurrence rate was 5%. ConclusionsDue to the absence of clinical practice guidelines, there are different therapeutic protocols. According to our experience, puncture-aspiration and administration of intravenous antibiotics is a safe, effective way to treat these patients. To determine the efficacy and safety of outpatient management, controlled studies would be needed.