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.

Vascular anatomy of the velopharyngeal muscles and its clinical implications: A fresh cadaveric study based on micro-computed tomography.

Poor speech improvement after levator veli palatini (LVP) reconstruction may be related to intraoperative vascular injury. We aimed to examine the vascular anatomy of the velopharyngeal muscles to provide a guide for arterial protection in cleft palate repair. Fresh adult cadaveric heads were injected with gelatin/lead oxide. The velopharyngeal specimens were stained with iodine and scanned using micro-computed tomography. Three-dimensional reconstruction models were obtained using a computer-aided design software. The ascending palatine artery (APaA), especially the posterior branch, is the main artery supplying the velopharyngeal muscles. The posterior branch of the APaA reaches the dorsal part of the musculus uvulae in the posterior one third of the soft palate (SP) and lies 1.75 mm (standard deviation, 0.06) under the nasal mucosa; the anterior branch penetrates the anterolateral side of the LVP to reach the anterior one third of the SP and lies 7.09 mm (0.03) under the oral mucosa. The posterior APaA, anterior ApaA, and ApaA trunk had mean diameters of 0.41 mm (0.04), 0.46 mm (0.06), and 0.65 mm (0.04) at 0.5, 1, and 1.5 cm distance from the palatal midline, respectively. To minimize vascular injury, mobilization of muscles during intravelar veloplasty should be performed within a distance of 1 cm from the palatal midline, and dissection of the oral submucosa should be reduced in the anterior one third of the SP, while wide dissection of the nasal submucosal should be avoided in the posterior one third of the SP.

Micro-Computed Tomography-Based Three-Dimensional Anatomical Structure of the Region Around the Pterygoid Hamulus.

OBJECTIVE: Palatoplasty would involve the structures around the pterygoid hamulus. However, clinicians hold different opinions on the optimal approach for the muscles and palatine aponeurosis around the pterygoid hamulus. The absence of a consensus regarding this point can be attributed to the lack of investigations on the exact anatomy of this region. Therefore, we used micro-computed tomography to examine the anatomical structure of the region surrounding the pterygoid hamulus. DESIGN: Cadaveric specimens were stained with iodine-potassium iodide and scanned by micro-computed tomography to study the structures of the tissues, particularly the muscle fibers. We imported Digital Imaging and Communications in Medicine images to Mimics to reconstruct a 3-dimensional model and simplified the model. RESULTS: Three muscles were present around the pterygoid hamulus, namely the palatopharyngeus (PP), superior constrictor (SC), and tensor veli palatini (TVP). The hamulus connects these muscles as a key pivot. The TVP extended to the palatine aponeurosis, which bypassed the pterygoid hamulus, and linked the PP and SC. Some muscle fibers of the SC originated from the hamulus, the aponeurosis of which was wrapped around the hamulus. There was a distinct gap between the pterygoid hamulus and the palatine aponeurosis. This formed a pulley-like structure around the pterygoid hamulus. CONCLUSIONS: Transection or fracture of the palatine aponeurosis or pterygoid hamulus, respectively, may have detrimental effects on the muscles around the pterygoid hamulus, which play essential roles in the velopharyngeal function and middle ear ventilation. Currently, cleft palate repair has limited treatment options with proven successful outcomes.

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.

Ostmann's Fat Pad-Does it Really Matter?

OBJECTIVE: To compare the size of Ostmann's fat pad (OFP) between healthy ears and ears with chronic otitis media with cholestatoma (COMwC) using magnetic resonance imaging (MRI). METHODS: Twenty-six patients with unilateral COMwC underwent mastoidectomy. Pre-operative MRI records were reviewed retrospectively. The healthy ears served as the control group. OFP is represented by the maximum diameter of the high intensity area medial to the tensor veli palatini muscle (TVP); M1. A reference diameter was defined from the medial border of OFP reaching the medial border of the medial pterygoid muscle; M2. Values of M1, M2 and the ratio of M1:M2 was compared between the healthy and pathological ear in each patient. RESULTS: All 26 patients (16 females,10 males) had unilateral cholestatoma. Mean age was 37.6 years (range 19-83). In the healthy (H) ears group, mean M1H was 2.04 ± 0.53 mm, mean M2H was 9.57 ± 2.57 mm.In the pathological (P) ears group; mean M1P was 2.03 ± 0.55 mm, mean M2P was 9.86 ± 2.37 mm. A comparison of M1 and M2 values between the healthy and pathological ear groups was not statistically significant (P = .853 and P = .509, respectively).Mean M1H:M2H ratio in the healthy ears group was 0.22 ± 0.05, mean M1P:M2P ratio in the pathological ear group was 0.21 ± 0.06. A comparison between these ratios found no significant statistical correlation (P = .607). CONCLUSION: The size of Ostmann's fat pad does not affect the development of chronic otitis media with cholestatoma in adults.

Morphological association between the muscles and bones in the craniofacial region.

The strains of inbred laboratory mice are isogenic and homogeneous for over 98.6% of their genomes. However, geometric morphometric studies have demonstrated clear differences among the skull shapes of various mice strains. The question now arises: why are skull shapes different among the mice strains? Epigenetic processes, such as morphological interaction between the muscles and bones, may cause differences in the skull shapes among various mice strains. To test these predictions, the objective of this study is to examine the morphological association between a specific part of the skull and its adjacent muscle. We examined C57BL6J, BALB/cA, and ICR mice on embryonic days (E) 12.5 and 16.5 as well as on postnatal days (P) 0, 10, and 90. As a result, we found morphological differences between C57BL6J and BALB/cA mice with respect to the inferior spine of the hypophyseal cartilage or basisphenoid (SP) and the tensor veli palatini muscle (TVP) during the prenatal and postnatal periods. There was a morphological correlation between the SP and the TVP in the C57BL6J, BALB/cA, and ICR mice during E15 and P0. However, there were not correlation between the TVP and the SP during P10. After discectomy, bone deformation was associated with a change in the shape of the adjacent muscle. Therefore, epigenetic modifications linked to the interaction between the muscles and bones might occur easily during the prenatal period, and inflammation seems to allow epigenetic modifications between the two to occur.

Anatomical study of the palatine aponeurosis: application to posterior palatal seal of the complete maxillary denture.

The palatine aponeurosis is a thin, fibrous lamella comprising the extended tendons of the tensor veli palatini muscles, attached to the posterior border and inferior surface of the palatine bone. In dentistry, the relationship between the "vibrating line" and the border of the hard and soft palate has long been discussed. However, to our knowledge, there has been no discussion of the relationship between the palatine aponeurosis and the vibrating line(s). Twenty sides from ten fresh frozen White cadaveric heads (seven males and three females) whose mean age at death was 79 years) were used in this study. The thickness of the mucosa including the submucosal tissue was measured. The maximum length of the palatine aponeurosis on each side and the distance from the posterior nasal spine to the posterior border of the palatine aponeurosis in the midline were also measured. The relationship between the marked borderlines and the posterior border of the palatine bone was observed. The thickness of the mucosa and submucosal tissue on the posterior nasal spine and the maximum length of the palatine aponeurosis were 3.4 mm, and 12.2 mm on right side and 12.8 mm on left, respectively. The length of the palatine aponeurosis in the midline was 4.9 mm. In all specimens, the borderline between the compressible and incompressible parts corresponded to the posterior border of the palatine bone.

The extended bundle of the tensor veli palatini: Anatomic consideration of the dilating mechanism of the Eustachian tube.

OBJECTIVE: The aim of this study was to analyze the topographical structures of the muscles surrounding the Eustachian tube. MATERIALS AND METHODS: We conducted macroscopic and histological studies of 24 halves of 12 heads from Japanese cadavers. RESULTS: The main findings were as follows: 1) the infero-lateral muscle bundles of the tensor veli palatini didn't turn medially at the pterygoid hamulus but were distributed laterally and continuous with the buccinator; 2) the tensor veli palatini attached laterally to the membranous part of the Eustachian tube; 3) the superior pharyngeal constrictor was not only adjacent to the buccinator at the pterygomandibular raphe but also had muscular continuation with it laterally and 4) some bundles of the superior pharyngeal constrictor adhered with the palatine aponeurosis. CONCLUSION: We believe that the cooperation of the muscles contributes to the dilating mechanism of the Eustachian tube, due to the complex topographical structures of the surrounding muscles: the tensor veli palatini, the levator veli palatini, the superior pharyngeal constrictor and the buccinator.

Endoscopic endonasal nasopharyngectomy: tensor veli palatine muscle as a landmark for the parapharyngeal internal carotid artery.

BACKGROUND: Endoscopic endonasal nasopharyngectomy(EEN) can be a promising option for select patients with recurrent nasopharyngeal carcinoma, but serious complications can occur in terms of parapharyngeal internal carotid artery (PPICA) injury. Several landmarks have been proposed for locating the PPICA. In this study, we investigated the spatial relationship between the tensor veli palatini (TVP) muscle and the PPICA in a cadaveric model. METHODS: Seven fresh cadaver heads were available for anatomic study. Eustachian tube and the levator veli palatine (LVP) muscle were partially sacrificed or truncated to maximize the surgical field, and the TVP muscle was carefully preserved. Complete dissection was defined as when the PPICA could be visualized. We then measured the distance between the posterior margin of the TVP muscle and PPICA (z-axis), and the distance from the midline of the nasopharynx to the PPICA (x-axis). RESULTS: Thirteen sides of the PPICA were successfully identified. The mean distance between the posterior margin of the TVP to the PPICA (z) was 20.3 mm (range, 12 to 28 mm), and the mean distance between the midline of the nasopharynx to the PPICA (x) was 19.6 mm (range, 15 to 24 mm). CONCLUSION: The PPICA was located in the same sagittal plane as the TVP muscle during dissection posteriorly. The PPICA appeared to lie around 2 cm laterally from the midline at around 2 cm in depth from the posterior margin of the TVP muscle. However, the exact position of the PPICA should be assessed using preoperative magnetic resonance imaging and intraoperative image-guided systems.

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.