Ultrasound-Guided Botulinum Neurotoxin Injection for Alleviating Cricopharyngeus Muscle Spasticity: A Cadaveric Feasibility Study with Nerve Ending Analysis.

Botulinum neurotoxin (BNT) injection into the cricopharyngeus muscle (CPM) under ultrasound (US) guidance is a minimally invasive technique performed to relieve cricopharyngeal dysphagia by reducing CPM spasticity. This technique is basically accessible only to both lateral sides of the CPM. This cadaveric study aimed to evaluate whether US-guided injection could effectively deliver BNT to abundant areas of gross nerve endings within the CPM. We utilized a newly modified Sihler's staining method to identify regions with abundant neural endings within the CPM while preserving the three-dimensional morphology of the muscle in 10 sides of 5 fresh cadavers. A mixture of 0.2 mL dye was injected into the 16 sides of CPM under US guidance in 8 cadavers. Nerve endings were abundant in posterolateral areas of the CPM; the injected dye was identified at the posterolateral area on 12 sides (12/16 side, 75%) without diffusion into the posterior cricoarytenoid muscle. The injection failed on four sides (two sides of the prevertebral fascia and two sides of the esophagus below the CPM). These results suggest that US-guided injection could be a feasible technique as it can deliver BNT to the most abundant nerve distribution areas within the CPM in most cases.

Magnetic Resonance Imaging of the Velopharynx: Clinical Findings in Patients with Velopharyngeal Insufficiency.

BACKGROUND: Magnetic resonance imaging (MRI) is the only imaging modality capable of directly visualizing the levator veli palatini (LVP) muscles: the primary muscles responsible for velopharyngeal closure during speech. MRI has been used to describe normal anatomy and physiology of the velopharynx in research studies, but there is limited experience with use of MRI in the clinical evaluation of patients with velopharyngeal insufficiency (VPI). METHODS: MRI was used to evaluate the velopharyngeal mechanism in patients presenting for VPI management. The MRI followed a fully awake, nonsedated protocol with phonation sequences. Quantitative and qualitative measures of the velopharynx were obtained and compared with age- and sex-matched individuals with normal speech resonance. RESULTS: MRI was completed successfully in 113 of 118 patients (96%). Compared with controls, patients with VPI after cleft palate repair had a shorter velum (P < 0.001), higher incidence of LVP discontinuity (P < 0.001), and shorter effective velar length (P < 0.001). Among patients with persistent VPI after pharyngeal flap placement, findings included a pharyngeal flap base located inferior to the palatal plane [11 of 15 (73%)], shorter velum (P < 0.001), and higher incidence of LVP discontinuity (P = 0.014). Patients presenting with noncleft VPI had a shorter (P = 0.004) and thinner velum (P < 0.001) and higher incidence of LVP discontinuity (P = 0.014). CONCLUSIONS: MRI provides direct evidence of LVP muscle anomalies and quantitative evaluation of both velar length and velopharyngeal gap. This information is unavailable with traditional VPI imaging tools, suggesting that MRI may be a useful tool for selecting surgical procedures to address patient-specific anatomic differences.

Cadaveric Study and Micro-Computed Tomography of the Anatomy of Palatine Aponeurosis and its Link to the Soft Palate Muscles and Pharyngeal Muscles.

OBJECTIVE: There have been few studies on the anatomy of palatine aponeurosis (PA). Herein, we elucidated the relationship between the PA and soft palate muscles and pharyngeal muscles. DESIGN: Two cadaveric specimens were dissected to observe the gross anatomy of the PA. Six cadaveric specimens were processed and scanned by micro-computed tomography to determine the elaborate anatomy. Images were exported to Mimics software to reconstruct a three-dimensional model. RESULTS: The PA covered the anterior (32.1%-38.8%) of the soft palate, extending from the tensor veli palatini (TVP) and connecting to 3 muscles: palatopharyngeus (PP), uvula muscle, and superior pharyngeal constrictor (SC). The SC and PP are attached to the PA on the medial side of the pterygoid hamulus. SC muscle fibers were attached to the hamulus, forming a distinct gap between the hamulus. Some muscle fibers of the PP and uvula originated from the PA. The PA extended from the TVP to the midline and the posterior edge of the hard palate. The PA was not uniformly distributed, which was complementary to the attached muscles in thickness. CONCLUSIONS: PA, as a flexible fibrous membrane, maintains the shape of the soft palate. It extends from the TVP and covers anteriorly about one-third of the soft palate. The PA provides a platform for the soft palate muscles and pharyngeal muscles, connecting to the PP, uvula muscle, and SC. These muscles are important for palatopharyngeal closure and middle-ear function. It is necessary to minimize the damage to the PA during surgical interventions.

Three-Dimensional Anatomy of the Palatopharyngeus and Its Relation to the Levator Veli Palatini Based on Micro-Computed Tomography.

BACKGROUND: Although multiple studies have been reported on the palatopharyngeus and levator veli palatini, their subtle anatomy and functions remain unclear. The authors elucidated the relationship between these muscles and their functional implications based on three-dimensional digital techniques. METHODS: Cadaveric specimens were stained with iodine-potassium iodide and scanned using micro-computed tomography. The muscle fibers were drawn on the exported Imaging and Communications in Medicine images to reconstruct a three-dimensional model and further simplified. RESULTS: In the soft palate, the palatopharyngeus was divided into three bundles. The largest inferior head was found to attach to the palatine aponeurosis, soft palate, and the hard palate on the oral side, which occupied approximately the anterior 28.4 to 36.2 percent of the soft palate in the midline. The superior head was thin and attached to the palatine aponeurosis and the surrounding mucosa on the nasal side. The posterior head was located posterior to the levator veli palatini with fibers attaching to the levator veli palatini and the median portion of the uvula. The levator veli palatini was clasped by the three heads of the palatopharyngeus. The fasciculi of the palatopharyngeus converged into a bundle of muscles at the pharynx and inserted into the lateral and posterior pharyngeal wall. CONCLUSIONS: The palatopharyngeus is the largest muscle that connects the soft palate and pharyngeal wall; it closely coordinates with the levator veli palatini to control levator veli palatini overlifting, narrow the velopharyngeal port with the help of the superior constrictor, and elevate the pharynx. The palatopharyngeus and levator veli palatini help each other in velopharyngeal closure through coordination from other muscles.

A Cadaveric and Magnetic Resonance Imaging Investigation of the Salpingopharyngeus.

Purpose The aim of the study was to update our information regarding the salpingopharyngeus (SP) muscle using cadaveric and in vivo magnetic resonance imaging (MRI) data. Primary objectives were to (a) observe the presence/absence of the muscle and (b) quantify and describe its dimensions and course. Method SP specimens from 19 cadavers (10 women, nine men) were analyzed. Following head bisection, measurements of SP, including width of the cartilaginous attachment (CW) and width of the superior muscle base (SMW), were taken before and after removal of the overlying mucosa. In addition, SP was analyzed in 15 healthy subjects (eight men, seven women) using high-resolution three-dimensional MRI data. CW and SMW measures were replicated in the paraxial MRI view. Results The presence of the salpingopharyngeal fold and muscle was confirmed bilaterally in all cadaveric and living subjects. Following mucosa removal, mean cadaveric CW and SMW measurements were 5.6 and 3.8 mm, respectively. Mean in vivo CW and SMW were 6.1 and 3.7 mm, respectively. Results from the hierarchical regression analyses revealed that, in both cadaveric and living groups, SMW is dependent on the relationship between age and body weight, after controlling for sex. Conclusions The salpingopharyngeal fold and SP muscle are always present bilaterally and can be quantified at the superior origin using both cadaveric and in vivo three-dimensional MRI data. Though both the superior origin and inferior course of SP are highly variable, the size of the SP muscle is dependent on characteristics known to affect muscle fibers, such as the relationship between age and body weight. Given the consistent and quantifiable presence of the SP muscle, its potential role in velopharyngeal function for speech and swallowing is reconsidered. Supplemental Material https://doi.org/10.23641/asha.14347859.

Early MRI Blood Volume Changes in Constrictor Muscles Correlate With Postradiation Dysphagia.

PURPOSE: Predicting individual patient sensitivity to radiation therapy (RT) for tumor control or normal tissue toxicity is necessary to individualize treatment planning. In head and neck cancer, radiation doses are limited by many nearby critical structures, including structures involved in swallowing. Previous efforts showed that imaging parameters correlate with RT dose; here, we investigate the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) blood volume (BV) changes in predicting dysphagia. METHODS AND MATERIALS: This study included 32 patients with locally advanced oropharyngeal squamous cell carcinoma treated with definitive chemoradiation on an institutional protocol incorporating baseline and early midtreatment DCE-MRI. BV maps of the pharyngeal constrictor muscles (PCM) were created, and BV increases midtreatment were correlated with the following parameters at 3 and 12 months post-RT: RT dose, Dynamic Imaging Grade of Swallowing Toxicity swallow score, aspiration frequency, European Organisation for Research and Treatment of Cancer HN35 patient-reported outcomes, physician-reported dysphagia, and feeding tube (FT) dependence. RESULTS: The mean BV to the PCMs increased from baseline to fraction 10, which was significant for the superior PCM (P = .006) and middle PCM (P < .001), with a trend in the inferior PCM where lower mean doses were seen (P = .077). The factors associated with FT dependence at 3 months included BV increases in the total PCM (correlation, 0.48; P = .006) and middle PCM (correlation, 0.50; P = .004). A post-RT increase in aspiration was associated with a BV increase in the superior PCM (correlation, 0.44; P = .013),and the increase in the total PCMs was marginally significant (correlation, 0.34; P = .06). The best-performing models of FT dependence (area under the receiver operating curve [AUC] = 0.84) and aspiration increases (AUC = 0.78) included BV increases as well as a mean RT dose to middle PCM. CONCLUSIONS: Our results suggest that midtreatment BV increases derived from DCE-MRI are an early predictor of dysphagia. Further investigation of these promising imaging markers to assess individual patient sensitivity to treatment and the patient's subsequent risk of toxicities is warranted to improve personalization of RT planning.

Velopharyngeal Muscle Morphology in Children With Unrepaired Submucous Cleft Palate: An Imaging Study.

OBJECTIVE: To identify quantitative and qualitative differences in the velopharyngeal musculature and surrounding structures between children with submucous cleft palate (SMCP) and velopharyngeal insufficiency (VPI) and noncleft controls with normal anatomy and normal speech. METHODS: Magnetic resonance imaging was used to evaluate the velopharyngeal mechanism in 20 children between 4 and 9 years of age; 5 with unrepaired SMCP and VPI. Quantitative and qualitative measures of the velum and levator veli palatini in participants with symptomatic SMCP were compared to noncleft controls with normal velopharyngeal anatomy and normal speech. RESULTS: Analysis of covariance revealed that children with symptomatic SMCP demonstrated increased velar genu angle (15.6°, P = .004), decreased α angle (13.2°, P = .37), and longer (5.1 mm, P = .32) and thinner (4 mm, P = .005) levator veli palatini muscles compared to noncleft controls. Qualitative comparisons revealed discontinuity of the levator muscle through the velar midline and absence of a musculus uvulae in children with symptomatic SMCP compared to noncleft controls. CONCLUSIONS: The levator veli palatini muscle is longer, thinner, and discontinuous through the velar midline, and the musculus uvulae is absent in children with SMCP and VPI compared to noncleft controls. The overall velar configuration in children with SMCP and VPI is disadvantageous for achieving adequate velopharyngeal closure necessary for nonnasal speech compared to noncleft controls. These findings add to the body of literature documenting levator muscle, musculus uvulae, and velar and craniometric parameters in children with SMCP.

Massive spontaneous haemorrhage in a plexiform neurofibroma: A case report and discussion of the literature.

Neurofibromatosis Type 1 (NF1) is a neurocutaneous tumour syndrome characterised by mutations in the NF1 gene and resultant neurofibromin protein. The condition is associated with several stigmata of variable penetrance, including various tumours. Massive and fatal haemorrhage arising from plexiform neurofibromas has been described in NF1 patients, though it is a rare clinical entity. The aetiology of massive haemorrhage in NF1 patients appears to be related to vasculopathy, including aneurysms and pseudoaneurysms, often arising within plexiform neurofibromas. There is currently no evidence-based consensus for managing this rare clinical emergency, likely as a result of its low incidence. We describe a case of massive haemorrhage in an NF1 patient managed via embolisation and discuss the literature.

The Changes in Pharyngeal Constrictor Muscles Related to Head and Neck Radiotherapy: A Systematic Review.

It is well known that radiation damage of the pharyngeal constrictor muscles, the glottic larynx, and the supraglottic larynx may lead to dysphagia, an unwanted effect of head and neck radiotherapy. The reduction of radiotherapy-induced dysphagia might be achieved by adaptive radiotherapy. Although the number of studies concerning adaptive radiotherapy of head and neck cancer is continuously increasing, there are only a few studies concerning changes in dysphagia-related structures during radiotherapy.The goal of this review is to summarize the current knowledge about volumetric, dosimetric, and other changes of the pharyngeal constrictor muscles associated with head and neck radiotherapy. A literature search was performed in the MEDLINE database according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The conclusions of 8 studies that passed the criteria indicate a significant increase in the volume and the thickness of the pharyngeal constrictor muscles during radiotherapy. Moreover, the changes in magnetic resonance imaging signal intensity of the pharyngeal constrictor muscles correlate with the absorbed dose (typically higher than 50 Gy) and also with the grade of dysphagia. This systematic review presents 2 variables, which are suitable for estimation of radiotherapy-related pharyngeal constrictor muscles changes-magnetic resonance imaging signal intensity and the thickness. In the case of the thickness, there is no consensus in the level of the measurement-C2 vertebra, C3 vertebra, and the middle of the craniocaudal axis are used. It seems that reference to a position associated with a vertebral body could be more reproducible and beneficial for future research. Although late pharyngeal toxicity remains a challenge in head and neck cancer treatment, better knowledge of radiotherapy-related changes in the pharyngeal constrictor muscles contributes to adaptive radiotherapy development and thus improves the treatment results.

Transient Velopharyngeal Insufficiency After Calcified Stylohyoid Ligament Resection.

Elongation of the stylohyoid process or calcification of the stylohyoid ligament is known as the Eagle syndrome. Mostly, it is seen incidentally on imaging or with extreme suspicion and usually patients are asymptomatic.Surgery is the preferred method in symptomatic patients. Transcervical or transoral methods may be preferred as surgical route.A 28-year-old female patient who had formerly underwent tonsillectomy presented with throat and ear pain. A neck computed tomography was performed, and the patient was diagnosed as Eagle Syndrome. Surgery was recommended.Patient developed transient velopharyngeal insufficiency on postoperative day 4. Ventilation exercise and follow-up was recommended. Complaints of the patient decreased on the 15th day.It should be kept in mind that stylohyoid ligament may be calcified in young age group and middle age group patients with dysphagia or odynophagia, and differential diagnosis should be performed. Another issue is the condition of velofaringeal insufficiency which may occur due to the damage of the pharynx muscles by deep dissection during surgery.

Influence of radiation dose to pharyngeal constrictor muscles on late dysphagia and quality of life in patients with locally advanced oropharyngeal carcinoma.

BACKGROUND AND OBJECTIVE: Patients with oropharyngeal carcinoma (OPC) often have difficulty swallowing, which may affect quality of life (QoL). Radiation dose to constrictor muscles plays an important role. METHODS: 54 patients with locally advanced OPC were evaluated after intensity-modulated radiotherapy. Data were collected at standardized intervals using the EORTC questionnaires QLQ-C30 and QLQ-HN35 within two years. The pharyngeal constrictors (superior, middle, and inferior) were each contoured as an organ at risk. Influence of dose to the constrictors (≥55 Gy vs. <55 Gy) on late dysphagia and QoL was analyzed using the t­test. RESULTS: Late radiation-induced dysphagia depends significantly on the dose to the lower pharyngeal constrictor. At a dose of ≥55 Gy, 14 (64%) patients developed dysphagia grade ≤2 and 8 (36%) patients grade ≥3. At a dose of <55 Gy, the distribution at the end of radiotherapy (RT) was similar: 22 (69%) patients with dysphagia grade ≤2, 10 (31%) with grade ≥3. There was no dose-dependent difference in the severity of dysphagia in the acute phase (p = 0.989). There were differences 18 months after the end of RT: ≥55 Gy: 19 (86%) patients showed dysphagia grade ≤2; 3 (14%) grade ≥3. At <55 Gy, 31 (97%) patients developed grade ≤2, 1 (3%) grade ≥3 (18 months: p = 0.001; 24 months: p = 0.000). Late dysphagia is also dependent on the dose level of the middle constrictor muscle (6 months: p = 0.000; 12 months: p = 0.005, 18 months: p = 0.034). After 24 months, there was no significant difference (p = 0.374). CONCLUSION: Radiation dose to the upper constrictor muscle appears to be of little relevance. The middle and lower constrictor should be given special consideration to avoid late dysphagia. Long-term QoL is independent on radiation dose.

Botulinum Toxin A Injection Using Esophageal Balloon Radiography Combined with CT Guidance for the Treatment of Cricopharyngeal Dysphagia.

Cricopharyngeal dysfunction, especially cricopharyngeal achalasia, is a common cause of dysphagia, while patients with brainstem stroke and medullary damage have a relatively high risk of cricopharyngeal achalasia. The aim of this article was to introduce an improved method of CT-guided method of injecting botulinum toxin A into the cricopharyngeus muscle using esophageal balloon radiography, and to assess the effect of the botulinum toxin A injection on swallowing performance. Seventeen patients with cricopharyngeal dysphagia were treated with botulinum toxin A injection using esophageal balloon radiography combined with CT guidance to the cricopharyngeal muscle. Primary outcome measures, including Functional Oral Intake Scale and Deglutition Handicap Index, were performed at baseline, 1 week, and 1 month after treatment. The Levene method was used to test the homogeneity of variance, and the Kruskal-Wallis test was used to compare the scores between the timepoints. Botulinum toxin A injection resulted in obvious improvement in 15 patients (88.2%) and no improvement in two patients (11.8%). Compared with the scores prior to treatment, the Functional Oral Intake Scale and Deglutition Handicap Index scores were significantly improved at 1 week (P < 0.001 and P = 0.008, respectively) and 1 month after the treatment (P = 0.001 and P < 0.001, respectively). Thus, CT-guided percutaneous injection of botulinum toxin A is probably a relatively safe, well-tolerated, and viable technique for the treatment of cricopharyngeal dysphagia caused by brainstem injury. Localization with a balloon radiography made the needle guidance easier to visualize.

A Dynamic Magnetic Resonance Imaging-Based Method to Examine In Vivo Levator Veli Palatini Muscle Function During Speech.

Purpose The aim of this study was to develop a method able to quantify levator veli palatini (LVP) muscle shortening and contraction velocities using dynamic magnetic resonance imaging (MRI) throughout speech samples and relate these measurements to velopharyngeal portal dimensions. Method Six healthy adults (3 men and 3 women, M = 24.5 years) produced syllables representing 4 different manners of production during real-time dynamic MRI scans. We acquired an oblique-coronal slice of the velopharyngeal mechanism, which captured the length of the LVP, and manually segmented each frame. LVP shortening and muscle velocities were calculated from the acquired images. Results Using our method, we found that subjects demonstrated greater LVP shortening and higher maximum contraction velocities during fricative and plosive syllable production than during nasal or vowel syllable production. LVP shortening and maximum contraction velocity positively correlated with velopharyngeal port depth. Conclusions In vivo LVP function differs between manners of production, as expected, and an individual's velopharyngeal portal dimensions influence LVP function. These measures, contextualized with the force-length and force-velocity muscle relationships, provide new insight into LVP function. Future studies could use this method to investigate LVP function in healthy speakers and individuals with velopharyngeal dysfunction and how function relates to velopharyngeal anatomy.

Targeted Intervention to Improve the Quality of Head and Neck Radiation Therapy Treatment Planning in the Netherlands: Short and Long-Term Impact.

PURPOSE: To benchmark and improve, through means of a targeted intervention, the quality of intensity modulated radiation therapy treatment planning for locally advanced head and neck cancer (HNC) in the Netherlands. The short and long-term impact of this intervention was assessed. METHODS AND MATERIALS: A delineated computed tomography-scan of an oropharynx HNC case was sent to all 15 Dutch radiation therapy centers treating HNC. Aims for planning target volume and organ-at-risk (OAR) dosimetry were established by consensus. Each center generated a treatment plan. In a targeted intervention, OAR sparing of all plans was discussed, and centers with the best OAR sparing shared their planning strategies. Impact of the intervention was assessed by (1) short-term (half a year after intervention) replanning of the original case and (2) long-term (1 and 3 years after intervention) planning of new cases. RESULTS: Benchmarking revealed substantial difference in OAR doses. Initial mean doses were 22 Gy (range, 15-31 Gy), 35 Gy (18-49 Gy), and 37 Gy (20-46 Gy) for the contralateral parotid gland, contralateral submandibular gland, and combined swallowing structures, respectively. Replanning after targeted intervention significantly reduced mean doses and variation, but clinically relevant differences still remained: 18 Gy (14-22 Gy), 28 Gy (17-45 Gy), and 29 Gy (18-39 Gy), respectively. One and 3 years later the variation remained stable. CONCLUSIONS: Despite many years of HNC intensity modulated radiation therapy experience, initial treatment plans showed surprisingly large variations. The simple targeted intervention used in this analysis improved OAR sparing, and its impact was durable; however, fairly large dose differences still continue to exist. Additional work is needed to understand these variations and to minimize them. A national radiation oncology platform can be instrumental for developing and maintaining high-quality planning protocols.

Growth Effects on Velopharyngeal Anatomy From Childhood to Adulthood.

Purpose The observed sexual dimorphism of velopharyngeal structures among adult populations has not been observed in the young child (4- to 9-year-old) population. The purpose of this study was to examine the age at which sexual dimorphism of velopharyngeal structures become apparent and to examine how growth trends vary between boys and girls. Method Static 3-dimensional magnetic resonance imaging velopharyngeal data were collected among 202 participants ranging from 4 to 21 years of age. Participants were divided into 3 groups based on age, including Group 1: 4-10 years of age, Group 2: 11-17 years of age, and Group 3: 18-21 years of age. Nine velopharyngeal measures were obtained and compared between groups. Results Significant sex effects were evident for levator length ( p = .011), origin to origin ( p = .018), and velopharyngeal ratio ( p = .036) for those in Group 2 (11-17 years of age). Sex effects became increasingly apparent with age, with 7 of 9 variables becoming significantly different between male and female participants in Group 3. Boys, in general, displayed a delayed growth peak in velopharyngeal growth compared to girls. Conclusion Results from this study demonstrate the growth of velopharyngeal anatomy with sexual dimorphism becoming apparent predominantly after 18 years of age. However, velopharyngeal variables displayed variable growth trends with some variables presenting sexual dimorphism at an earlier age compared to other velopharyngeal variables.

Deep Learning-Based Delineation of Head and Neck Organs at Risk: Geometric and Dosimetric Evaluation.

PURPOSE: Organ-at-risk (OAR) delineation is a key step in treatment planning but can be time consuming, resource intensive, subject to variability, and dependent on anatomical knowledge. We studied deep learning (DL) for automated delineation of multiple OARs; in addition to geometric evaluation, the dosimetric impact of using DL contours for treatment planning was investigated. METHODS AND MATERIALS: The following OARs were delineated with DL developed in-house: both submandibular and parotid glands, larynx, cricopharynx, pharyngeal constrictor muscle (PCM), upper esophageal sphincter, brain stem, oral cavity, and esophagus. DL contours were benchmarked against the manual delineation (MD) clinical contours using the Sørensen-Dice similarity coefficient. Automated knowledge-based treatment plans were used. The mean dose to the manually delineated OAR structures was reported for the MD and DL plans. RESULTS: DL delineation of all OARs took <10 seconds per patient. For 7 of 11 OARs, the average Sørensen-Dice similarity coefficient was good (0.78-0.83). However, performance was lower for the esophagus (0.60), brainstem (0.64), PCM (0.68), and cricopharynx (0.73), often because of variations in MD. Although the average dose was statistically significantly higher in the DL plans for the inferior PCM (1.4 Gy) and esophagus (2.2 Gy), these average differences were not clinically significant. Dose to 28 of 209 (13.4%) and 7 of 209 (3.3%) OARs was >2 Gy higher and >2 Gy lower, respectively, in the DL plans. CONCLUSIONS: DL-based segmentation for head and neck OARs is fast; for most organs and most patients, it performs sufficiently well for treatment-planning purposes. It has the potential to increase efficiency and facilitate online adaptive radiation therapy.

A prospective longitudinal assessment of MRI signal intensity kinetics of non-target muscles in patients with advanced stage oropharyngeal cancer in relationship to radiotherapy dose and post-treatment radiation-associated dysphagia: Preliminary findings from a randomized trial.

PURPOSE: To assess quantitative signal intensity (SI) kinetics obtained from serial MRI of swallowing muscles as a potential imaging biomarker of radiation-induced dysphagia in oropharyngeal cancer (OPC) patients receiving radiotherapy (RT). METHODS: Patients were enrolled under an IRB approved Phase II/III randomized trial. Patients underwent serial MRIs at pre-, mid-, and post-RT. Normalized T1, T1+ contrast (T1 + C), and T2 SI for swallowing muscle volumes-of-interest (VOIs) were collected and delta SI changes (Δ) were calculated. Mid- and post-RT SI relative to baseline were assessed and correlations between radiation dose and percent change in SI were calculated. Independent samples' t-tests were used to compare the percent change of SI between patients divided into two groups based on dysphagia status post-RT. RESULTS: Forty-six patients with stage III/IV HPV+ OPC were included in this study. Relative to baseline, mean T2 and T1 + C SIs for middle pharyngeal constrictor were both significantly higher at mid- and post-RT (p < 0.004 for all). Superior pharyngeal constrictor also showed a significant increase in T1 + C SI at mid-RT (p = 0.0004). Additional muscle VOIs showed significant changes post-RT, but not earlier at mid-RT. Both mid- and post-RT doses were significantly correlated with the percent change of normalized T2 and T1 + C SI for examined muscle VOIs (p < 0.002). Mean percent changes of normalized T2 SI at mid-RT relative to baseline for all muscle VOIs were significantly higher in patients who developed grade ≥2 dysphagia relative to patients with no/mild dysphasia (mean Δ%: 8.2% vs 1.9%; respectively, p = 0.002). However, at post-RT, these changes were only significant in T1 SI (11.2% vs -1.3%; p < 0.0001). CONCLUSION: Signal intensity kinetics of radiation injury can be broadly correlated with the functional muscular defect. Serial MRI during the course of RT may provide an opportunity to quantitatively track muscular pathology for subclinical detection of patients at high risk to develop dysphagia.

Variations in Velopharyngeal Structure in Adults With Repaired Cleft Palate.

OBJECTIVE: The purpose of this study was to examine differences in velopharyngeal structures between adults with repaired cleft palate and normal resonance and adults without cleft palate. DESIGN: Thirty-six English-speaking adults, including 6 adults (2 males and 4 females) with repaired cleft palate (M = 32.5 years of age, SD = 17.4 years) and 30 adults (15 males and 15 females) without cleft palate (M = 23.3 years of age, SD = 4.1 years), participated in the study. Fourteen velopharyngeal measures were obtained on magnetic resonance images and compared between groups (cleft and noncleft). RESULTS: After adjusting for body size and sex effects, there was a statistically significant difference between groups for 10 out of the 14 velopharyngeal measures. Compared to those without cleft palate, participants with repaired cleft palate had a significantly shorter hard palate height and length, shorter levator muscle length, shorter intravelar segment, more acute levator angles of origin, shorter and thinner velum, and greater pharyngeal depth. CONCLUSION: Although significant differences were evident in the cleft palate group, individuals displayed normal resonance. These findings suggest that a wide variability in velopharyngeal anatomy can occur in the presence of normal resonance, particularly for those with repaired cleft palate. Future research is needed to understand how anatomic variability impacts function, such as during speech.

Posture-Dependent Dysphagia After Botulinum Toxin Type A Injection at Sternocleidomastoid in a Patient With Athetoid Cerebral Palsy.

Cervical dystonia is a common issue in patients with athetoid cerebral palsy. Botulinum toxin injection to dystonic cervical muscles is a well-recognized treatment option, but it is known to be associated with dysphagia. Previously reported cases of dysphagia after botulinum toxin injection to the sternocleidomastoid muscle were related to the regional spread of toxin to the pharyngeal muscles. We report a unique case of posture-dependent dysphagia due to preactivation of the suprahyoid and infrahyoid muscles to compensate for impaired head stabilization by the weakened sternocleidomastoid muscle while swallowing. This case suggests a possible mechanism of dysphagia in patients with athetoid cerebral palsy.