Fresh Cadaver Heads Research Articles

The posterior pedicled inferior turbinate-nasoseptal flap: a potential combined flap for skull base reconstruction.

To develop a combined pedicled flap comprising the mucoperiosteum and mucoperichondrium of the inferior turbinate, lateral nasal wall, nasal floor, and nasal septum based on the posterior lateral nasal artery, a branch of the sphenopalatine artery, for the reconstruction of skull base defects resulting from endoscopic expanded endonasal approaches. Eleven fresh adult cadaver heads were dissected. Arterial distribution patterns of the inferior turbinate, lateral nasal wall, nasal floor, and nasal septum were investigated. The posterior pedicled inferior turbinate-nasoseptal flap was designed, measured, and harvested, and its ability to cover ventral skull base defects was examined. The inferior turbinate artery and/or posterior lateral nasal artery had 3.19 ± 1.47 (range 2-7) branches [mean outer diameter of largest branch, 0.40 ± 0.10 (range 0.24-0.60) mm] that anastomosed with the nasoseptal artery. These anastomosing arteries allowed the posterior lateral nasal artery to supply arterial blood to the nasoseptal mucoperichondrium and mucoperiosteum. Mean flap length was 100.65 ± 5.61 (range 91.43-109.44) mm, and minimum and maximum widths were 25.21 ± 2.29 (range 22.36-30.23) and 44.53 ± 5.02 (range 36.45-54.10) mm, respectively. Mean flap area was 3090.69 ± 288.08 (range 2612.97-3880.09) mm(2). The flap covered defects extending from the frontal sinus to the foramen magnum in all specimens. Harvesting of a posterior pedicled inferior turbinate-nasoseptal flap is feasible. It should be considered a useful option for the reconstruction of large defects involving the anterior skull base, planum sphenoidale, sella turcica, and/or clivus.

Broad Tip Modification in Asian Patients Undergoing Rhinoplasty Using the Low-Lateral Cartilage Cruciate Overlap Technique.

Asian patients undergoing cosmetic rhinoplasty often want surgeons to concentrate on the broad nasal tip. Modifying the cartilage framework is considered to be the fundamental strategy; during the modification procedures, the cephalic portion of the lower lateral cartilage is often excised and discarded. However, given the supporting function and volumetric filling properties of autologous cartilage, the cephalic cartilage should and can be salvaged by using our cruciate overlap technique. To introduce a novel technique in modification of broad nasal tip in Asian patients undergoing rhinoplasty and assess its efficacy and safety. Dissection of 5 fresh cadaver head specimens was performed and the plausibility and reliability of the new procedure were determined at Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. In addition, the cruciate overlap technique was performed in 43 Chinese patients between January 1, 2011, and December 31, 2013, and the surgical results were assessed subjectively and objectively during the follow-up period, ranging from 12 to 36 months, with the final follow-up November 30, 2014. Anthropometric measurements of patients' noses preoperatively and postoperatively were taken and the patients' complications were reviewed. Cadaveric evaluation, subjective and objective assessments of the surgical results (rated on a scale of 1 to 4, with 4 indicating much improvement from the preoperative level), nasal measurements of the patients, and evaluation of the complications. The mean size of the cartilaginous flap in the cruciate overlap technique was 12.0 mm long and 3.0 mm wide, allowing for 180° rotation and graft coverage, with the nasal cartilage framework protected from collapse. Mean (SD) scores for the subjective and objective judgment of the outcomes were 3.3 (0.4) and 3.5 (0.3), respectively. Moreover, nasal measurements demonstrated significant postoperative improvement by increasing the mean nasal tip protrusion (from 14.3 [1.5] to 16.7 [2.0] mm) and reducing the mean tip width (from 22.7 [1.7] to 18.2 [1.6] mm) and tip angle (from 101.0° [6.3°] to 87.7° [6.7°]) (all P < .001). Acceptable ranges of edema, ecchymosis, and pain were observed in the early postoperative period and resolved within a short period. No aesthetic or functional adverse effects were reported during the follow-up period. The cruciate overlap technique is an efficacious and reliable alternative for modification of broad nasal tips in Asian patients undergoing rhinoplasty. 4.

Quantitative and qualitative analysis of the working area obtained by endoscope and microscope in pterional and orbitozigomatic approach to the basilar artery bifurcation using computed tomography based frameless stereotaxy: A cadaver study

Objective:Basilar aneurisms are one of the most complex and challenging pathologies for neurosurgeons to treat. Endoscopy is a recently rediscovered neurosurgical technique that could lend itself well to overcome some of the vascular visualization challenges associated with this pathology. The purpose of this study was to quantify and compare the basilar artery (BA) bifurcation (tip of the basilar) working area afforded by the microscope and the endoscope using different approaches and image guidance.Materials and Methods:We performed a total of 9 dissections, including pterional (PT) and orbitozygomatic (OZ) approaches bilaterally in five whole, fresh cadaver heads. We used computed tomography based image guidance for intraoperative navigation as well as for quantitative measurements. We estimated the working area of the tip of the basilar, using both a rigid endoscope and an operating microscope. Operability was qualitatively assessed by the senior authors.Results:In microscopic exposure, the OZ approach provided greater working area (160 ± 34.3 mm2) compared to the PT approach (129.8 ± 37.6 mm2) (P > 0.05). The working area in both PT and OZ approaches using 0° and 30° endoscopes was larger than the one available using the microscope alone (P < 0.05). In the PT approach, both 0° and 30° endoscopes provided a working area greater than a microscopic OZ approach (P < 0.05) and an area comparable to the OZ endoscopic approach (P > 0.05).Conclusion:Integration of endoscope and microscope in both PT and OZ approaches can provide significantly greater surgical exposure of the BA bifurcation compared to that afforded by the conventional approaches alone.

A cadaveric study in endoscopic 3D visualization of posterior fossa neurovascular complexes

Background: The use of 3D endoscopy for posterior fossa surgery gradually adopted. In this study we compare the 3D to classic 2D endoscopy in evaluating neurovascular complexes in posterior fossa. Methods: Twenty retrosigmoid craniotomies, with a maximal diameter of 2cm were performed under neuronavigation on 10 fresh cadaveric heads. The posterior fossa dura matter was opened with a C-shaped incision and the base of the dural flap was placed over the sigmoid sinus. We used 3D and 2D endoscopes, with 0 and 45 degree angulations, connected to high definition camera lenses for optimal visualization of posterior fossa structures. Results: The superior, middle and inferior neurovascular complexes of the cerebellopontine angle were better visualized with 3D comparing to 2D endoscope. A detailed view of the porus trigeminous and structures associated with the tentorial incisura was also attained with 3D endoscopy. Conclusion: The high quality and resolution obtained by 3D endoscopy makes it a potentially valuable surgical and teaching tool in the armamentarium for endoscopic posterior fossa surgery. The stereoscopic view of the critical neurovascular structures of the posterior fossa, offered by 3D images, allows for a more detailed dissection in the difficult area of the cerebellopontine angle.

Characterization of the temporomandibular joint of the harbour porpoise (Phocoena phocoena) and Risso's dolphin (Grampus griseus)

ObjectivesThe temporomandibular joint (TMJ) in cetaceans is largely uncharacterized. This study aims to describe the macroscopic, microscopic, biochemical and biomechanical features of the TMJ of two species of the suborder Odontoceti: the harbour porpoise (Phocoena phocoena) and Risso's dolphin (Grampus griseus). Furthermore, we aim to elucidate the structure–function relationship of their TMJs and their possible role in echolocation. DesignThe TMJs from fresh cadaver heads of harbour porpoise (n=4) and Risso's dolphin (n=2) acquired from stranding were examined. Following macroscopical evaluation, the TMJs were investigated for their histological, mechanical and biochemical properties. ResultsThe TMJs of the studied odontocetes were found to be fundamentally different from other mammals. Macroscopically, the TMJ lacks the typical joint cavity found in most mammals and is essentially a syndesmosis. Histological and microstructural analysis revealed that the TMJ discs were composed of haphazardly intersecting fibrous-connective tissue bundles separated by adipose tissue globules and various calibre blood vessels and nerve fibres. The collagen fibre composition was primarily collagen type I with lesser amounts of collagen type II. Sulphated glycosaminoglycan (sGAG) content was lower compared to other studied mammals. Finally, mechanical testing demonstrated the disc was stronger and stiffer in the dorsoventral direction than in the mediolateral direction. ConclusionThe spatial position of the TMJ, the absence of an articulating synovial joint, and the properties of the TMJ discs all reflect the unique suction-feeding mechanism adopted by the harbour porpoise and Risso's dolphin for underwater foraging. In addition, the presence of unique adipose globules, blood vessels and nerves throughout the discs may indicate a functional need beyond food apprehension. Instead, the disc may play a role in neurological sensory functions such as echolocation.

Three-Dimensional Computed Tomographic Evaluation of Bilateral Sagittal Split Osteotomy Lingual Fracture Line and Le Fort I Pterygomaxillary Separation in Orthognathic Surgery Using Cadaver Heads: Ultrasonic Osteotome Versus Conventional Saw

The purpose of this study was to observe the quality of the fracture line on the lingual side of the mandible after sagittal split osteotomy and the quality of pterygomaxillary separation after Le Fort Iosteotomy using the BoneScalpel ultrasonic osteotome. Bimaxillary procedures, according to the standard protocol, were performed using 10 fresh cadaver heads. The ultrasonic osteotome was used in the study group, and a reciprocating saw was used in the control group. Three-dimensional reconstructions of postoperative computed tomographic scans were obtained. The lingual ramus fracture pattern and the pterygomaxillary separation pattern were observed, classified, and compared. Postoperative dissections of the skulls were performed to assess the integrity of the infra-alveolar nerve and the descending palatine artery. No significant differences were found in the cutting time of bone between the BoneScalpel and the sagittal saw. Of the sagittal split osteotomies in the study group, 90% showed a good pattern (vertical pattern of fracture line extending to the inferior border of the mandible running behind the mandibular canal) compared with 50% of the sagittal split osteotomies in the control group. Ideal separation of the pterygoid plates without fractures was observed in 80% of the Le Fort I osteotomies in the study group compared with 50% of the osteotomies in the control group. High-level fractures occurred in 30% of cases in the control group compared with none in the study group. The integrities of the infra-alveolar nerve and the descending palatine artery were preserved in all cases. Use of the ultrasonic BoneScalpel did not require more time than the conventional method. An improved pattern of lingual fracture lines in mandibular sagittal split osteotomy procedures and the pattern of pterygomaxillary separation in Le Fort I osteotomy procedures were observed.

Impedance testing on cochlear implants after electroconvulsive therapy.

Cochlear implants (CI) are neural prostheses that restore hearing to individuals with profound sensorineural hearing loss. The surgically implanted component consists of an electrode array, which is threaded into the cochlea, and an electronic processor, which is buried under the skin behind the ear. The Food and Drug Administration and CI manufacturers contend that electroconvulsive therapy (ECT) is contraindicated in CI recipients owing to risk of damage to the implant and/or the patient. We hypothesized that ECT does no electrical damage to CIs. Ten functional CIs were implanted in 5 fresh cadaveric human heads. Each head then received a consecutive series of 12 unilateral ECT sessions applying maximum full pulse-width energy settings. Electroconvulsive therapy was delivered contralaterally to 5 CIs and ipsilaterally to 5 CIs. Electrical integrity testing (impedance testing) of the electrode array was performed before and after CI insertion, and after the first, third, fifth, seventh, ninth, and 12th ECT sessions. Electroconvulsive therapy was performed by a staff psychiatrist experienced with the technique. Explanted CIs were sent back to the manufacturer for further integrity testing. No electrical damage was identified during impedance testing. Overall, there were statistically significant decreases in impedances (consistent with no electrical damage) when comparing pre-ECT impedance values to those after 12 sessions. There was no statistically significant difference (P > 0.05) in impedance values comparing ipsilateral to contralateral ECT. Manufacturer testing revealed no other electrical damage to the CIs. Electroconvulsive therapy does not seem to cause any detectable electrical injury to CIs.

Radiological assessment of the inferior alveolar artery course in human corpse mandibles.

CT assessment of the entire course of the inferior alveolar artery (IAA) within the mandibular canal. After contrast medium injection (180 or 400 mg/ml iodine concentration) into the external carotid arteries of 15 fresh human cadaver heads, the main IAA's position in the canal (cranial, buccal, lingual or caudal) was assessed in dental CT images of partially edentulous mandibles. The course of the main IAA could be followed at both iodine concentrations. The higher concentration gave the expected better contrast, without creating artefacts, and improved visibility of smaller arteries, such as anastomotic sections, dental branches and the incisive branch. The main IAA changed its position in the canal more often than so far known (mean 4.3 times, SD 1.24, range 2-7), but with a similar bilateral course. A cranial position was most often detected (42 %), followed by lingual (36 %), caudal (16 %) and buccal ( 6 %). With this non-invasive radiologic method, the entire course of the main IAA in the mandibular canal could be followed simultaneously with other bone structures on both sides of human cadaver mandibles. This methodology allows one to amend existing anatomical and histological data, which are important for surgical interventions near the mandibular canal. • Contrast medium injection displayed the inferior alveolar artery's course on mandibular CTs • An iodine concentration of 400 mg/ml enabled visibility until the chin • Frequent position changes of the artery in the mandibular canal were detected • Cranial and lingual positions were most often determined • Course similarities on the respective left and right sides were found.

Head positioning for anterior circulation aneurysms microsurgery.

To study the ideal patient's head positioning for the anterior circulation aneurysms microsurgery. We divided the study in two parts. Firstly, 10 fresh cadaveric heads were positioned and dissected in order to ideally expose the anterior circulation aneurysm sites. Afterwards, 110 patients were submitted to anterior circulation aneurysms microsurgery. During the surgery, the patient's head was positioned accordingly to the aneurysm location and the results from the cadaveric study. The effectiveness of the position was noted. We could determine mainly two patterns for head positioning for the anterior circulation aneurysms. The best surgical exposure is related to specific head positions. The proper angle of microscopic view may minimize neurovascular injury and brain retraction.

The temporomandibular joint of California sea lions (Zalophus californianus): Part 1 – Characterisation in health and disease

ObjectivesThis study aimed to characterise the histologic, biomechanical and biochemical properties of the temporomandibular joint (TMJ) of California sea lions. In addition, we sought to identify structure–function relationships and to characterise TMJ lesions found in this species. DesignTemporomandibular joints from fresh cadaver heads (n=14) of California sea lions acquired from strandings were examined macroscopically and microscopically. The specimens were also evaluated for their mechanical and biochemical properties. Furthermore, if TMJ arthritic changes were present, joint characteristics were described and compared to healthy joints. ResultsFive male and 9 female specimens demonstrated macroscopically normal fibrocartilaginous articular surfaces and fibrous discs in the TMJ. Out of the 9 female specimens, 4 specimens had TMJ lesions were seen either in the articular surface or the disc. Histologically, these pathologic specimens demonstrated subchondral bone defects, cartilage irregularities and inflammatory cell infiltrates. The normal TMJ discs did not exhibit significant direction dependence in tensile stiffness or strength in the rostrocaudal direction compared with the mediolateral direction among normal discs or discs from affected joints. The TMJ discs were not found to be anisotropic in tensile properties. This feature was further supported by randomly oriented collagen fibres as seen by electron microscopy. Furthermore, no significant differences were detected in biochemical composition of the discs dependent upon population. ConclusionThe TMJ and its disc of the California sea lion exhibit similarities but also differences compared to other mammals with regards to structure–function relationships. A fibrous TMJ disc rich in collagen with minimal glycosaminoglycan content was characterised, and random fibre organisation was associated with isotropic mechanical properties in the central region of the disc.

Soft-tissue composition of the columella and potential relevance in rhinoplasty.

The columella serves as the medial limb of the nasal tripod, with the medial crura functioning as the cartilaginous framework. Although soft-tissue of the columella may have both functional and aesthetic implications, it is a topic not often discussed in the rhinoplasty literature. The objective of this study was to evaluate soft-tissue histology of the columella and discuss findings that are pertinent to clinical rhinoplasty. Ten fresh cadaver heads were obtained from The University of Texas Southwestern Willed Body Program. En bloc resections of the columella were harvested. Specimens were fixed in formalin and embedded in paraffin. Subsequently, specimens were sectioned serially and stained. Staining with hematoxylin and eosin was performed to evaluate collagen and fat composition. Van Gieson elastin stain was completed to assess for elastin fibers. Laterally, the columella was framed by stratified squamous epithelium, which transitioned to mucosa at the level of the membranous septum. An areolar tissue plane was found between the skin and adjacent medial crura. Much greater soft-tissue volume was present between the bilateral medial crura. Soft-tissue composition was found to be heterogenous, with varying distributions of tissue at different levels of the columella. Present in notable volume were fibroblasts, collagen fibers, elastin fibers, adipocytes, and neurovascular structures. Columella soft-tissue is remarkable for the presence of fibroblasts, collagen and elastin fibers, muscle fibers, and adipocytes. These findings may have significant implications regarding surgical maneuvers influencing tip projection, effects of aging on the nose, and columellar aesthetics and function.

Anatomic comparison of the endonasal and transpetrosal approaches for interpeduncular fossa access.

The interpeduncular cistern, including the retrochiasmatic area, is one of the most challenging regions to approach surgically. Various conventional approaches to this region have been described; however, only the endoscopic endonasal approach via the dorsum sellae and the transpetrosal approach provide ideal exposure with a caudal-cranial view. The authors compared these 2 approaches to clarify their limitations and intrinsic advantages for access to the interpeduncular cistern. Four fresh cadaver heads were studied. An endoscopic endonasal approach via the dorsum sellae with pituitary transposition was performed to expose the interpeduncular cistern. A transpetrosal approach was performed bilaterally, combining a retrolabyrinthine presigmoid and a subtemporal transtentorium approach. Water balloons were used to simulate space-occupying lesions. "Water balloon tumors" (WBTs), inflated to 2 different volumes (0.5 and 1.0 ml), were placed in the interpeduncular cistern to compare visualization using the 2 approaches. The distances between cranial nerve (CN) III and the posterior communicating artery (PCoA) and between CN III and the edge of the tentorium were measured through a transpetrosal approach to determine the width of surgical corridors using 0- to 6-ml WBTs in the interpeduncular cistern (n = 8). Both approaches provided adequate exposure of the interpeduncular cistern. The endoscopic endonasal approach yielded a good visualization of both CN III and the PCoA when a WBT was in the interpeduncular cistern. Visualization of the contralateral anatomical structures was impaired in the transpetrosal approach. The surgical corridor to the interpeduncular cistern via the transpetrosal approach was narrow when the WBT volume was small, but its width increased as the WBT volume increased. There was a statistically significant increase in the maximum distance between CN III and the PCoA (p = 0.047) and between CN III and the tentorium (p = 0.029) when the WBT volume was 6 ml. Both approaches are valid surgical options for retrochiasmatic lesions such as craniopharyngiomas. The endoscopic endonasal approach via the dorsum sellae provides a direct and wide exposure of the interpeduncular cistern with negligible neurovascular manipulation. The transpetrosal approach also allows direct access to the interpeduncular cistern without pituitary manipulation; however, the surgical corridor is narrow due to the surrounding neurovascular structures and affords poor contralateral visibility. Conversely, in the presence of large or giant tumors in the interpeduncular cistern, which widen the spaces between neurovascular structures, the transpetrosal approach becomes a superior route, whereas the endoscopic endonasal approach may provide limited freedom of movement in the lateral extension.

Comparison of Conventional Transcrestal Sinus Lift and Ultrasound-Enhanced Transcrestal Hydrodynamic Cavitational Sinus Lift for the Filling of Subantral Space: A Human Cadaver Study.

The implant-supported prosthetic rehabilitation of the posterior maxilla may require sinus-grafting procedures due to poor quality and low volume of bone. This can be accomplished using a "lateral window" sinus augmentation or with an osteotome sinus floor elevation (OSFE). The hydrodynamic ultrasonic cavitational sinus lift (HUCSL) (Intralift) is derived from the osteotome technique and allows the reduction of some of the traumatic effects of the osteotome technique. The aim of this study was to compare OSFE and the HUCSL procedures on fresh human cadaver heads. Primary outcomes were the height and width of the grafting area in the sinus floor area. Eighty-four maxillary sinuses were selected. On each fresh cadaver head, 2 sinus lifts were done using OSFE and HUCSL in the maxillary sinuses. Computerized tomography scans were performed on each head before and after the surgeries. Measurements were done on radiologic pictures using dedicated software, and the integrity of the sinus membrane was observed after dissecting the maxillae. The use of HUCSL resulted in a significantly higher sinus floor augmentation in the mesio-distal and bucco-palatal direction compared with the osteotome technique (P < .001). There was no correlation between mesio-distal and bucco-palatal diameters of sinus floor augmentation when only the osteotome protocol was considered (r = 0.27 and P = .08). In contrast, the mesio-distal and bucco-palatal diameters of floor augmentation were correlated when the HUCSL protocol was considered (r = 0.79, P < .001). HUCSL represents a good alternative method for sinus floor elevation.

A New Technique of Virtual Modeling of Individual Patient Airways in Obstructive Sleep Apnea

Objectives: Up to 14% of the US population is estimated to have obstructive sleep apnea (OSA) related to obesity. Other than continuous positive airway pressure, treatments have had variable results since the exact site(s) of obstruction and the optimal method of modifying those sites with devices or surgery can be difficult to establish. We introduce a technique for modeling the upper airway that shows the behavior of the airway and predicts the location of collapse in OSA. Methods: Accurate modeling of air to solid fluid-structure interaction, challenging to model in the past, was accomplished using ANSYS software applied to a 3-dimensional rendering of an OSA patient’s airway (with an AHI of 87.6/h) using thin-cut computed tomographic scan data. Viscoelastic properties of the pharyngeal walls, tongue and palate, not previously well characterized, were measured using 5 fresh porcine cadaver heads with a Bose ElectroForce test instrument with Dynamic Mechanical Analysis software. Various dynamic displacements were applied to tissue samples and associated forces measured simultaneously to obtain dynamic material properties. Results: Areas of lowest pressure during inspiration were identified as likely regions of collapse during apneic episodes, such as the base of the tongue with pressures as low as –4730 Pa (–48.23 cm H2O), similar to values reported in human esophageal pressure measurements in upper airway resistance syndrome. Conclusions: This novel investigation virtually and accurately models the upper airway in OSA, and allows virtual modification of the airway to predict effects of treatment.

Evaluation of the potential of automatic segmentation of the mandibular canal using cone-beam computed tomography

We aimed to investigate the effectiveness of software for automatically tracing the mandibular canal on data from cone-beam computed tomography (CT). After the data had been collected from one dentate and one edentate fresh cadaver head, both a trained Active Shape Model (ASM) and an Active Appearance Model (AAM) were used to automatically segment the canals from the mandibular to the mental foramen. Semiautomatic segmentation was also evaluated by providing the models with manual annotations of the foramina. To find out if the tracings were in accordance with the actual anatomy, we compared the position of the automatic mandibular canal segmentations, as displayed on cross-sectional cone-beam CT views, with histological sections of exactly the same region. The significance of differences between results were analysed with the help of Fisher's exact test and Pearson's correlation coefficient. When tracings based on AAM and ASM were used, differences between cone-beam CT and histological measurements varied up to 3.45mm and 4.44mm, respectively. Manual marking of the mandibular and mental foramina did not improve the results, and there were no significant differences (p=0.097) among the methods. The accuracy of automatic segmentation of the mandibular canal by the AAM and ASM methods is inadequate for use in clinical practice.

A functional periorbital subunit allograft: Vascular, anatomic, and technical considerations for future subunit facial transplantation

Injury to the face can result in the loss of critical specialized structures (the eyelids, lips, ears and nose). Vascularized composite allotransplantation (VCA) allows the surgeon to replace exactly what has been lost. The success of the clinical face transplants suggests the possibility of transplanting specialized units of the face. In this study we explore the neurovascular anatomy and technical specifics for harvest of a functional composite eyelid subunit flap. 12 fresh cadaver heads were studied, each yielding two flaps (N=24). The facial (FA) and superficial temporal arteries (STA) were cannulated and injected with a gelatin/acrylic dye mixture. 6 cadaver heads were evaluated via high-resolution three-dimensional CT scans with contrast. The dye injected into the STA uniformly stained the tissue of the eyelid/periorbital subunit. Injection into the FA resulted in staining of the skin and soft tissues in the medial canthal region and superior eyelid skin in 66% of specimens. CT scan studies confirm our findings with injection into the STA resulting in contrast infiltration of the palpebral arterial arcades in all cases. Injection of the FA resulted in contrast infiltration of the palpebral arterial arcades in 2 of 3 cases. Based this study, a periorbital flap can be based on the STA. Motor innervation of the flap is via the zygomatic and buccal branches of the facial nerve with sensory innervation via the infraorbital, supraorbital and supratrochlear nerves. FA could be used, but its ability to perfuse the entire flap was inconsistent.

Defining the Fat Compartments in the Neck: A Cadaver Study

Cervicoplasty is an important component of aesthetic facial and neck surgery, but the fat content in this area has not been described. The authors identify anatomic compartments of fat in the neck (specifically the areas relevant to surgical management), quantify the fat in each compartment, and describe the relationships between each compartment and the submandibular glands. The skin was removed from 10 fresh cadaver heads. Each compartment of fat was weighed, along with the submandibular gland. Supraplatysmal fat was found between the skin and the platysma muscle, and it was compartmentalized into suprahyoid and infrahyoid fat. Subplatysmal fat was found deep to the platysma and between the medial edges of the anterior digastric in the midline; this fat also fell into suprahyoid and infrahyoid compartments. The "very deep" fat was deep to the anterior digastric muscles and submandibular gland, and adherent to the strap muscles. On average, supraplatysmal fat represented 44.7% of the fat in the neck, the subplatysmal fat represented 30.7%, and the submandibular gland represented 24.5%. The very deep fat was scant, representing less than 1% of the fat in the neck. This anatomic study provides a comprehensive review of fat in the neck, and the results should serve as an additional guide as surgeons approach this challenging area in surgical rejuvenation.

Schneiderian Membrane Detachment Using Transcrestal Hydrodynamic Ultrasonic Cavitational Sinus Lift: A Human Cadaver Head Study and Histologic Analysis

Recent studies have suggested the osteogenic layer of the periosteum at the base of the sinus membrane to play a key role in bone regeneration after sinus lift procedures. Thus, atraumatic detachment of the sinus membrane with an intact periosteum seems mandatory. The present histologic study of fresh human cadaver heads investigated the detachment behavior and histologic integrity of the detached periosteum after application of the transcrestal hydrodynamic ultrasonic cavitational sinus lift (tHUCSL-INTRALIFT). A total of 15 sinuses in 8 fresh human cadaver heads were treated using tHUCSL-INTRALIFT. After surgery, they were checked macroscopically for damage to the sinus membrane and then processed for histologic inspection under light microscopy. A total of 150 histologic specimens, randomly selected from the core surgical sites, were investigated using hematoxylin-eosin (HE), Azan, and trichrome staining. None of the 150 inspected specimens showed any perforation or dissection of the periosteum from the subepithelial connective tissue and respiratory epithelium and were fully detached from the bony antrum floor. The connecting Sharpey fibers revealed to be cleanly separated from the sinus floor in all specimens. The results of the present study suggest tHUCSL-INTRALIFT should be used to perform predictable and safe detachment of the periosteum from the bony sinus floor as a prerequisite for undisturbed and successful physiologic subantral bone regeneration.

Transverse cervical and great auricular nerve distribution in the mandibular area: A study in human cadavers

The angle of the jaw is innervated by the auricular branch of the superficial cervical plexus (SCP). Cervical cutaneous nerves of the CP carry the sensation from the antero-lateral cervical skin. It is clinically relevant to identify the cervical cutaneous nerve distribution and the nerve point using superficial landmarks but published studies describing the emerging patterns and cervical cutaneous nerve branch distributions in the mandible are rare. The overlap between the cervical and trigeminal and facial nerve distributions and anastomoses is highly variable. The objective of this study was to characterize the distribution of the SCP nerves in the different parts of the mandible. Two hundred and fifty fresh and formalin-fixed human cadaver heads were microdissected to observe the distribution of the transverse cervical (TCN) and great auricular (GAN) nerves. Two main groups (G1 and G2) based on the emergence of the TCN and GAN behind the posterior edge of the sternocleidomastoid muscle and three types (T1, T2, and T3) based on their distribution in the different mandibular parts were observed. Statistical analysis showed that parameters related to the mandibular side (P = 0.307), gender (P = 0.218), and group (P = 0.111) did not influence the facial distribution of these nerves. The only parameter influencing the distribution was the type of nerve (GAN and TCN) (P < 0.001). In the face, the SCP reached the mandible in 97% of cases, its distribution and extent were subject-dependent. These results confirmed that the SCP could supply accessory innervation to the mandible through the TCN.

Endoscopic Endonasal Surgical Approach to the Oculomotor Trigone from the Cavernous Sinus

Knowledge of anatomy visualized endoscopically is necessary to perform endoscopic surgical procedures safely. The cavernous sinuses are complicated structures with major blood vessels and nerves seated deeply in the center of the skull base. Anatomical orientation during surgery is essential for deep and narrow skull base surgery. While performing surgery involving the cavernous sinuses, understanding of the structures identifiable via a transsphenoidal view can allow comprehension of the relationship between a lesion and the surrounding structures, thus preventing intraoperative complications. The objective of this study was to dissect the neurovascular structures in the cavernous sinus deeply inside the oculomotor trigone through a transsphenoidal view, and to determine the relationships among anatomical landmarks in the path of surgery. Ten fresh silicone-injected cadaveric heads were evaluated. Four millimeter-diameter rigid endoscopes with 0° and 30° rod-lenses were utilized to perform an endonasal transsphenoidal approach. The detailed position and course of the major components in each cavernous sinus were assessed under panoramic view. We also validated the utility of this approach by successfully excising a huge pituitary adenoma.