Three-dimensional Analysis of the Muscles Related to the So-Called "Pterygomandibular Raphe": An Anatomical and Histological Study.

The pterygomandibular raphe (PMR) is a tendinous bundle between the bucinator (BM) and the superior constrictor of pharynx (SC) and has been considered essential for swallowing. Despite its functional significance, previous studies reported that the PMR is not always present. Another study reported presence of the connecting fascia between the BM and deep temporalis tendon (dTT). Therefore, the present study analyzed the three-dimensional relationship between the BM, SC, and dTT. We examined 13 halves of 11 heads from adult Japanese and Caucasian cadavers: eight halves macroscopically and five halves histologically. There was no clear border between the BM and SC in any specimens macroscopically. The BM attachment varied depending on its levels. At the level of the superior part of the internal oblique line, the BM fused with the SC with no clear border. At the level of the midpart of the internal oblique line of the mandible, the BM attached to the dTT directly, and the SC attached to the dTT via collagen fibers and the BM. Based on these results, these muscles should be described as the BM/dTT/SC (BTS) complex. The three-dimensional relationship of the BTS complex might result in the so-called "pterygomandibular raphe." The BTS complex could be important as a muscle coordination center in chewing and swallowing.

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.

The pharyngeal plexus: an anatomical review for better understanding postoperative dysphagia.

The pharyngeal plexus is an essential anatomical structure, but the contributions from the glossopharyngeal and vagus nerves and the superior cervical ganglion that give rise to the pharyngeal plexus are not fully understood. The pharyngeal plexus is likely to be encountered during various anterior cervical surgical procedures of the neck such as anterior cervical discectomy and fusion. Therefore, a detailed understanding of its anatomy is essential for the surgeon who operates in and around this region. Although the pharyngeal plexus is an anatomical structure that is widely mentioned in literature and anatomy books, detailed descriptions of its structural nuances are scarce; therefore, we provide a comprehensive review that encompasses all the available data from this critical structure. We conducted a narrative review of the current literature using databases like PubMed, Embase, Ovid, and Cochrane. Information was gathered regarding the pharyngeal plexus to improve our understanding of its anatomy to elucidate its involvement in postoperative spine surgery complications such as dysphagia. The neural contributions of the cranial nerves IX, X, and superior sympathetic ganglion intertwine to form the pharyngeal plexus that can be injured during ACDF procedures. Factors like surgical retraction time, postoperative hematoma, surgical hardware materials, and profiles and smoking are related to postoperative dysphagia onset. Thorough anatomical knowledge and lateral approaches to ACDF are the best preventing measures.

Morphology of the Upper Esophageal Sphincter or Cricopharyngeus Muscle Revisited: A Study Using Adult and Fetal Specimens.

Histological examination of specimens from 22 donated elderly cadavers and 15 human fetuses revealed that the cricopharyngeus muscle (CPM) provided (1) posterior circular muscle fibers adjacent to the external aspect of the uppermost esophageal circular muscle and (2) a thin anterior sling connecting to that same muscle. Another thick lateral bundle of longitudinal muscle originated independently from a fascia covering the posterior cricoarytenoideus muscle, extended laterally and posteriorly, and occupied a space after the CPM had disappeared at the anterolateral angle of the esophagus below the cricoid. The thick fascia contained abundant elastic fibers along the internal surface of the pharyngeal constrictors (posteromedial elastic lamina), but was interrupted or discontinued near the cricoid origin of the CPM. As no submucosal smooth muscles or elastic fibers were connected to it, the CPM did not accompany a specific elastic structure at the interface between the pharyngeal and esophageal muscles. In fetuses, the medial half of the CPM was inserted into the cricoid while the lateral half continued to the sternothyroideus muscle or ended at a fascia covering the cricothyroideus. These anterolateral ends provided a mechanical load for longitudinal growth of the pharyngeal constrictors. Consequently, the CPM was unlikely to develop and grow to form the upper esophageal sphincter, and the muscle bundle crossing the lateral aspect of the pharyngo-esophageal junction appeared to have a secondary passive role as a sphincter. This situation contrasts with that of another sphincter in the human body formed from striated muscle. Clin. Anat., 33:782-794, 2020. © 2019 Wiley Periodicals, Inc.

Anatomical status of the human palatopharyngeal sphincter and its functional implications.

PURPOSE: The transition muscle between the palatopharyngeus (PP) and the superior constrictor of the pharynx (SCP) encircles the pharyngeal isthmus from behind and is designated as the palatopharyngeal sphincter (PPS). The PPS is inferred to play important roles for velopharyngeal closure, but its existence remains controversial and its roles have been regarded as being played by the SCP. The present study aimed to clarify the anatomical status and functional implications of the PPS. MATERIALS AND METHODS: Macroscopic and microscopic examinations were performed on 39 and 4 cadavers, respectively. In the former, the bilateral PPSs and their adjacent structures were exposed from outside and/or inside. In the latter, the velums embedded in paraffin were cut into frontal or sagittal sections and alternately processed with HE and Azan stains. RESULTS: The PPS originated from the nasal aspect of the lateral half of the palatine aponeurosis and the inferior margin of the medial pterygoid plate and was distinguishable from the PP descending in and along the palatopharyngeal arch and the cranialmost portion of the SCP in its origin. It passed dorsally on the lateral side of the levator veli palatini and traversed around the salpingopharyngeal fold running longitudinally. It then entered below the SCP and ran toward the pharyngeal raphe with SCP muscle fibers intermingled. CONCLUSIONS: The PPS is a muscle distinct from the SCP. Its contraction produces Passavant's ridge and conceivably enhances the efficiency of velopharyngeal closure by pressing the salpingopharyngeal fold and the musculus uvulae ridge against the velum.

Magnetic Resonance Imaging of Velar Muscle Tissue Distribution in Healthy Adults.

OBJECTIVES: To examine muscle tissue distribution along the length of the velum in living individuals using magnetic resonance imaging (MRI). DESIGN: Using the three-dimensional MRI data acquired from 10 normal white adults, two area measures including the muscular area and the total velar area were obtained from 10 oblique slices running perpendicular to velar length. A polynomial regression analysis was performed where the proportion of the muscular to the total velar area was regressed on the slice numbers running along the length of the velum. RESULTS: The proportion of the muscular to total velar area increased from the anterior section of the velum, reaching a maximum (33.24%) in the midsection, and decreasing in the posterior section of the velum. A third-order (cubic) polynomial function that best illustrated the proportional data (R(2) = .47) was derived. CONCLUSIONS: The present study demonstrated that MRI is a viable tool to examine the muscle tissue distribution of the velum in living individuals. Although the overall pattern in the muscle tissue distribution of the healthy velum was similar to that reported in previous literature based on cadaver specimens, the participants in the present study appeared to have greater muscular proportion of the velum. The muscular proportion measure derived from the healthy living individuals can be used as an additional parameter accounting for sufficient intravelar muscle mass for future studies.

Anthropometric Analysis of the Velopharynx and Related Craniometric Dimensions in Three Adult Populations Using MRI.

OBJECTIVE: The purpose of this study is to examine effects of sex, race, and craniometry among three distinct racial groups of adults with normal velopharyngeal anatomy and to determine whether craniofacial structures could be used to predict velopharyngeal structures. METHODS: A total of 88 adults across three racial groups including white, black, and Asian (Japanese) participated. Magnetic resonance images were obtained using a high-resolution, three-dimensional anatomical scan. Measurements were obtained on the levator veli palatini muscle, velum, and craniofacial structures. RESULTS: Head circumference was used as a covariate to control the effect of overall cranial size on the analyses. Palate height, linear cranial base, and face height and width vary based on sex, with men demonstrating larger values compared with women. Linear base values, cranial base angle, and face width vary significantly based on race, with Japanese subjects showing the smallest anterior to posterior measures and larger face-width values. Levator muscle measures, excluding angle measures, vary significantly (P < .0001) based on sex. There was no statistically significant difference (P > .05) among racial groups in the levator muscle measures. Velar length and thickness varied significantly based on race and sex. CONCLUSIONS: This is the first study to examine the interaction of race and sex on levator muscle morphology. In spite of the differences in velar dimensions, no significant differences were found in muscle size, specifically the levator veli palatini, which is contained within the velum.

Age-Related Changes in Pharyngeal Lumen Size: A Retrospective MRI Analysis.

Age-related loss of muscle bulk and strength (sarcopenia) is often cited as a potential mechanism underlying age-related changes in swallowing. Our goal was to explore this phenomenon in the pharynx, specifically, by measuring pharyngeal wall thickness and pharyngeal lumen area in a sample of young versus older women. MRI scans of the neck were retrospectively reviewed from 60 women equally stratified into three age groups (20s, 60s, 70+). Four de-identified slices were extracted per scan for randomized, blinded analysis: one mid-sagittal and three axial slices were selected at the anterior inferior border of C2 and C3, and at the pit of the vallecula. Pixel-based measures of pharyngeal wall thickness and pharyngeal lumen area were completed using ImageJ and then converted to metric units. Measures of pharyngeal wall thickness and pharyngeal lumen area were compared between age groups with one-way ANOVAs using Sidak adjustments for post-hoc pairwise comparisons. A significant main effect for age was observed across all variables whereby pharyngeal wall thickness decreased and pharyngeal lumen area increased with advancing age. Pairwise comparisons revealed significant differences between 20s versus 70+ for all variables and 20s versus 60s for all variables except those measured at C2. Effect sizes ranged from 0.54 to 1.34. Consistent with existing sacropenia literature, the pharyngeal muscles appear to atrophy with age and consequently, the size of the pharyngeal lumen increases.

Spatial relationship between the palatopharyngeus and the superior constrictor of the pharynx.

PURPOSE: The palatopharyngeus and the superior constrictor act during swallowing. However, because they overlap one another, their morphologies have been controversial. This study examined these muscles to clarify their configuration and interrelationships. METHODS: The attachments and the fiber arrangement of the superior constrictor and the palatopharyngeus were gross anatomically examined in 28 Japanese cadavers. RESULTS: The most superior fibers of the superior constrictor arose from the palate and interfused with the lateral fibers of the palatopharyngeus. Consequently, their origins and insertions were arranged in a continuous line, respectively, and these flat muscles formed a sheet. The palatopharyngeus rotated 90 degrees, from the origin to the insertion, about its long axis, and its superior and inferior surfaces turned into internal and external, respectively. Its lateral fibers passed on the internal surface of the superior constrictor, and these two muscles were inserted into the pharyngeal raphe with an overlap, indicating that the muscular sheet was folded back. Its medial fibers consisted of two layers at the origin and were interdigitated with the insertion of the levator veli palatini. The superior layer was joined by the salpingopharyngeus and dispersed into the pharyngeal wall. The inferior one was joined by the stylopharyngeus and descended along the palatopharyngeal arch to be inserted into the thyroid cartilage and the epiglottis. CONCLUSIONS: These two muscles formed a sheet that was partially folded back. It is suggested that the superior constrictor and the lateral fibers cooperate as sphincters, and the medial fibers and the stylopharyngeus as elevators.

Anatomical considerations of the longitudinal pharyngeal muscles in relation to their function on the internal surface of pharynx.

The aim of this study was to clarify the topography of the longitudinal pharyngeal muscles and to relate the findings to pharyngeal muscular function. Forty-four specimens (22 right and 22 left sides) from embalmed Korean adult cadavers (13 males, 9 females; age range, 46-89 years; mean age, 69.2 years) were used in this study. The palatopharyngeus muscle originated from the palatine aponeurosis and the median part of the soft palate on oral aspect; it ran downward and lateralward, respectively. The palatopharyngeus muscle, which held the levator veli palatini, was divided into two bundles, medial and lateral, according to the positional relationship with the levator veli palatini. The lateral bundle of the palatopharyngeus muscle was divided into two parts: longitudinal and transverse. The pharyngeal longitudinal muscles were classified into the following four types (I-IV) depending on the area of insertion: they were inserted into the palatine tonsil, epiglottis, arytenoid cartilage, piriform recess, thyroid cartilage, and pharyngeal wall. The transverse part of the palatopharyngeus muscle plays a role as a sphincter. Palatopharyngeus and levator veli palatini muscles help each other to function effectively in the soft palate. The present findings suggest that the pharyngeal muscles are involved not only in swallowing but also in respiration and phonation via their attachment to the laryngeal cartilage.

Gross anatomical observations of attachments of the middle pharyngeal constrictor.

The pharyngeal muscles overlap each other and some of their parts have different areas of origin. Such arrangements make the interrelationships among pharyngeal muscles complicated. This study investigated the attachments of the middle constrictor to clarify its configuration and re-examine its functions. The gross anatomies of the pharyngeal and neighboring muscles were examined in 41 cadavers. The middle constrictor arose from the stylohyoid ligament and the hyoid bone, and its fibers were divided into three overlapping groups. The anterosuperior group ascended posterosuperiorly from the ligament and the lesser horn and fanned out. The middle group ascended posterosuperiorly from the greater horn and fanned out. The posteroinferior group fanned out from the posterior part of the greater horn, while the middle constrictor arose internally to the hyoglossus; some fibers often passed externally, and their fibers sometimes intersected around the lingual artery, which ran between them. Some fibers attached to the hyoglossus, occasionally to the stylohyoid and the posterior belly of the digastric, but seldom to the lingual artery and the triticeal cartilage in the thyrohyoid ligament. The three groups were inserted into the pharyngeal raphe, and the descending fibers joined the longitudinal pharyngeal muscles. The ascending and descending fibers rarely reached the top of the pharynx and the thyroid cartilage, respectively. The fiber arrangement suggested that, besides constriction of the pharynx, the ascending and descending fibers of the middle constrictor can act as an elevator muscle, and the irregular attachments could affect the functions of the muscles and vessels.

A description of arterial variants in the transoral approach to the parapharyngeal space.

This study demonstrates variations in the vascular anatomy of the parapharyngeal space (PPS) as seen from the transoral approach compared with the transcervical approach. The PPS was dissected in injected cadaveric specimens. Anatomical measurements, including those of branches of the external and internal carotid arteries (ECA and ICA) and the styloglossus and stylopharyngeus muscles, were recorded and analyzed. In 67% (8/12) of cases, the ascending palatine artery (APA) originated from the facial artery and crossed the styloglossus muscle. The diameter of the APA at its origin was 1.4 ± 0.3 mm. In 75% (9/12) of cases, the ascending pharyngeal artery (aPA) arose from the medial surface of the ECA near its origin. In 58% (7/12) of cases, the aPA ascended vertically between the ICA and the lateral pharynx to the skull base, along the longus capitus muscle. The aPA crossed the styloglossus muscle 12.6 ± 3.9 mm from the insertion into the tongue. In 92% (11/12) of cases, the ECA and ICA were separated by the styloid diaphragm and pharyngeal venous plexus. In 8% (1/12), the ECA bulged into the parapharyngeal fat between the styloglossus and stylopharyngeus muscles adjacent to the pharyngeal constrictors. Knowledge of the precise anatomy of the PPS is important for transoral robotic surgery (TORS). Control of the vessels that supply and traverse the PPS can help the TORS surgeon avoid those critical structures and reduce surgical morbidity and potential hemorrhage.

Both head extension and mouth opening impair the ability to swallow in the supine position.

Head position and mouth opening in the supine position may impair the ability to swallow. If this does occur, it would lead to retention of intra-oral fluids during dental treatment, which would lead to stimulation of the cough reflex. This study was conducted to investigate how head position and mouth opening affect swallowing ability. The water swallowing test was performed in 13 healthy adult subjects in the supine position. The subjects were asked to swallow 10 mL of water that was injected into the mouth in a single attempt. After swallowing, the residual intra-oral water was suctioned and its volume was measured. An electromyogram (EMG) of the suprahyoid (SH) muscles was also recorded during the test. The duration of SH muscle activity and peak amplitude of SH EMG were examined. The water swallowing test was performed under three head positions (neutral, extended and flexed) and four mouth opening patterns (interincisal distances of 0, 20, 30 and 40 mm). The wider the subject opened the mouth, the more the water remained in the mouth after swallowing. The residual volume of water was more in the extended position compared with that in the neutral and flexed positions. Peak amplitude of SH EMG decreased with mouth opening. Duration of SH muscle activity was longer in the extended position than in the neutral and flexed positions. Head extension and mouth opening can induce difficulty in swallowing in the supine position by extending the duration of SH muscle activity while reducing its intensity.

Effects of gravity on the velopharyngeal structures in children using upright magnetic resonance imaging.

Objective : The influence of gravity on the velopharyngeal structures in children is unknown. The purpose of this study is to compare the velopharyngeal mechanism in the upright and supine positions while at rest and during sustained speech production in children between 4 and 8 years old. Methods : A 0.6 Tesla open-type, multipositional magnetic resonance imaging scanner was used to image subjects in the upright and supine positions. The scanning protocol included a T2 fluid attenuation inversion recovery and an oblique coronal turbo spin echo scan with short scanning durations (7.9 seconds) to enable visualization of the velopharyngeal anatomy during rest and production of sustained /i/ and /s/. Results : The magnetic resonance imaging protocol used for this study enabled successful visualization of the velopharyngeal anatomy in the sagittal and oblique coronal planes at rest and during sustained phonation of /i/ and /s/. Positional differences demonstrated a small nonsignificant (P > .05) variation for velar measures (length, thickness, and height), retrovelar space, and levator veli palatini measures (length and angles of origin). Conclusions : Gravity had a negligible effect on velar length, velar thickness, velar height, retrovelar space, levator muscle length, and levator angles of origin. Supine imaging data can be translated to an upright activity such as speech. This is the first study to provide normative levator muscle lengths for children between 4 and 8 years old. Upright imaging may be a promising tool for difficult-to-test populations.

Motor functions in trumpet playing-a real-time MRI analysis.

INTRODUCTION: The function of the orofacial and pharyngeal musculature for sound generation in brass instruments is insufficiently investigated. The contribution of muscles defying direct observation remains poorly understood. Time-resolved magnetic resonance imaging (MRI) allows visualization of muscle function as well as changes of the oropharyngeal cavities during muscle activation. METHODS: We used fast 3-T MRI imaging to analyze motor activation during sound generation in brass instruments. Twelve professional trumpeters were analyzed at different pitch, loudness and dynamic. MR images were analyzed for position of the mouthpiece to lips and teeth, pivoting, nasopharyngeal closure and changes in the area of oral and pharyngeal cavity. RESULTS: Of the 12 subjects, eight positioned the mouthpiece mainly to the upper lip, three in equal parts to upper and lower lip, and only one mostly to the lower lip. The last turned out to be the only subject with upward pivoting. All subjects had a complete velopharyngeal closure. Measurements of the oral and pharyngeal cavities showed an increase when subjects were playing higher pitches. The increase in areas of oral and pharyngeal cavity was present also when switching from lower to higher loudness and when performing crescendo to decrescendo. Enlargement of the oral and pharyngeal cavity was less pronounced with increasing loudness. But no general difference in change of oral and pharyngeal cavity could be observed. CONCLUSIONS: The present study shows that it is possible to measure motor function and its implications on oral as well as pharyngeal cavities during sound generation in brass instruments. These changes seem to follow a reproducible pattern.

The upper esophageal sphincter is not round: a pilot study evaluating a novel, physiology-based approach to upper esophageal sphincter dilation.

OBJECTIVES: Recent basic science investigations have suggested that the upper esophageal sphincter (UES), in cross section, is not round, but that it more closely approximates a kidney shape. Dilation with simultaneous use of two cylindrical dilators provides a novel, physiology-based approach to UES distention. We evaluated the initial safety and efficacy of UES dilation with simultaneous use of two controlled radial expansion balloon dilators. METHODS: Using a computerized database, we reviewed the charts of all persons who underwent UES dilation with simultaneous use of two radial expansion balloon dilators between December 1, 2011, and March 15, 2012. Information regarding patient demographics, indications, technique, and complications was abstracted. Self-reported swallowing impairment was assessed with the validated 10-item Eating Assessment Tool (EAT-10). RESULTS: Ten individuals underwent simultaneous dilation with two dilators. Their mean age was 65 years (SD, 14 years), and 7 (70%) of them were male. The indications for dilation were radiation-induced UES stenosis (50%), cricopharyngeus muscle dysfunction (30%), upper esophageal web (10%), and anastomotic stricture (10%). After the double-balloon dilation, no complications were reported. The mean EAT-10 score improved significantly, from 34.3 (SD, 13.5) to 16.7 (SD, 8.4), after the simultaneous dilation (p = 0.003). CONCLUSIONS: Pilot data suggest that simultaneous dilation of the UES with two controlled radial expansion balloon dilators is feasible, safe, and effective. Future investigation is necessary to confirm the safety of this technique in a larger cohort and to use objective measures of efficacy to compare the technique to conventional dilation with a single dilator.

Evaluation of morphological features of palatopharyngeus insertion into the thyroid cartilage.

The attachment of the palatopharyngeus extended from the posterior end of the thyroid cartilage to the posterior margin of the inferior constrictor attachment that might contribute to successive swallowing movements. Laryngeal elevation is essential for proper swallowing and breathing. Recently, clinical research has demonstrated that the palatopharyngeus, a longitudinal muscle of the pharynx, is involved in the elevation of the larynx. However, the morphological relationship between the larynx and palatopharyngeus remains unclear. In the present study, we analyzed the attachment site and characteristics of the palatopharyngeus in the thyroid cartilage. We evaluated 14 halves of seven heads from Japanese cadavers (average age: 76.4 years); 12 halves, anatomically and two halves histologically. A part of the palatopharyngeus, which originated from the inferior aspect of the palatine aponeurosis, was attached to the inner and outer surfaces of the thyroid cartilage through collagen fibers. The attachment area extends from the posterior end of the thyroid cartilage to the posterior margin of the attachment site of the inferior constrictor. The palatopharyngeus may elevate the larynx with the suprahyoid muscles and contribute to successive movements of swallowing with surrounding muscles. Based on our findings and previous studies, palatopharyngeus with various muscle bundle directions may be essential for the coordination of continuous swallowing events.

Structural analysis of muscles elevating the hyolaryngeal complex.

A critical event of pharyngeal swallowing is the elevation of the hyolaryngeal complex to open the upper esophageal sphincter. Current swallowing theory assigns this function to the submental and thyrohyoid muscles. However, the attachments of the long pharyngeal muscles indicate that they could contribute to this function, yet their role is uninvestigated in humans. In addition, there is evidence the posterior digastric and stylohyoid contribute to hyoid elevation. A cadaver model was used to document the structural properties of muscles. These properties were used to model muscle groups as force vectors and analyze their potential for hyolaryngeal elevation. Vector magnitude was determined using physiological cross-sectional areas (PCSAs) of muscles calculated from structural properties of muscle taken from 12 hemisected cadaver specimens. Vector direction (lines of action) was calculated from the three-dimensional coordinates of muscle attachment sites. Unit force vectors in the superior direction of submental, suprahyoid (which includes the submental muscles), long pharyngeal, and thyrohyoid muscles were derived and compared by an analysis of variance (ANOVA) to document each muscle's potential contribution to hyolaryngeal elevation. An ANOVA with Tukey HSD post hoc analysis of unit force vectors showed no statistically significant difference between the submental (0.92 ± 0.24 cm(2)) and long pharyngeal (0.73 ± 0.20 cm(2)) muscles. Both demonstrated greater potential to elevate the hyolaryngeal complex than the thyrohyoid (0.49 ± 0.18 cm(2)), with P < 0.01 and P < 0.05, respectively. The suprahyoid muscles (1.52 ± 0.35 cm(2)) demonstrated the greatest potential to elevate the hyolaryngeal complex: greater than both the long pharyngeal muscles (P < 0.01) and the thyrohyoid (P < 0.01). The submental and thyrohyoid muscles by convention are thought to elevate the hyolaryngeal complex. This study demonstrates that structurally the long pharyngeal muscles have similar potential to contribute to this critical function, with the suprahyoid muscles having the greatest potential. If verified by functional data, these findings would amend current swallowing theory.

Gross anatomical study of the human palatopharyngeus muscle throughout its entire course from origin to insertion.

The palatopharyngeus (PP) extends throughout the entire length of the pharynx and probably plays an important role in deglutition, but its spatial distribution remains undefined in some respects. This study was designed to clarify the exact distribution of the PP indispensable for understanding its functions. Using 50 cadavers, the PP and its neighboring muscles were bilaterally exposed in both surfaces of the pharynx. The PP was composed of two divisions: longitudinal and transverse. It is already known that the longitudinal PP is divided into two fasciculi sandwiching the levator veli palatini (LVP) immediately after originating from the palatine aponeurosis. However, we newly discovered a fasciculus originating from the uvula, and further regarded the salpingopharyngeus as another fasciculus of origin. The four fasciculi united to descend through the palatopharyngeal arch and inserted into the thyroid cartilage and beneath the mucosa of the hypopharynx. The transverse PP occupied a location transitional between the PP and superior constrictor (SC), where it originated from the palatine aponeurosis and passed dorsally to encircle the pharyngeal isthmus and reach the pharyngeal raphe. Although whether it belongs to the PP or SC has remained controversial, we regarded it as a portion of the PP from the evolutionary perspective and proposed anatomical criteria for differentiating it from the SC. The wide distribution of the PP suggests that it acts not only to elevate the pharynx or depress the soft palate, but also as a nasopharyngeal sphincter when closing the pharyngeal isthmus.

[Endoscopic transoral retropharyngeal lymphadenectomy].

Objective:The aim of this study is to explore the anatomy and surgical approach of retropharyngeal lymphadenectomy via endoscopic transoral approach. Methods:The retropharyngeal spaces were studied with three fresh frozen cadaver head （6 sides） in the anatomical laboratory of Eye, Ear, Nose and Throat Hospital of Fudan University through endoscopic transoral approach. The superior pharyngeal constrictor muscle, medial pterygoid muscle, tendon of tensor veli palatini muscle, fat of prestyloid space, ascending palatine artery and its branches, styloglossus, stylopharyngeus, stylohyoideus, external carotid artery, levator veli palatini, carotid sheath, ascending pharyngeal artery and longus capitis muscle were revealed in order. The above-mentioned structures were photographed with a 0° Karl Storz nasal endoscope and adjacent relationships were recorded. A case of metastatic retropharyngeal lymphadenopathy was reviewed and the surgical methods and techniques of retropharyngeal lymphadenectomy via endoscopic transoral approach were introduced in detail. Results:The retropharyngeal space and related anatomical structures were exposed through endoscopic transoral approach in all specimens. The styloglossus, stylopharyngius and levator veli palatini are the markers of locating the internal carotid artery. The superior pharyngeal constrictor muscle, medial pterygoid muscle, styloid muscle group, longus capitis muscle and carotid sheath are the markers that can be used to locate the retropharyngeal lymph nodes. Ascending palatine artery, ascending pharyngeal artery and internal carotid artery are the main arteries involved in retropharyngeal lymphadenectomy via endoscopic transoral approach. Conclusion:Endoscopic transoral approach is a new surgical technique to perform retropharyngeal lymphadenectomy safely and completely.