Successful Hypoglossal Nerve Upper Airway Stimulator Implantation After Chemoradiotherapy for Oropharynx Malignancy Complicated by Mandibular Osteoradionecrosis.

This case demonstrates the first successful treatment of obstructive sleep apnea with hypoglossal nerve upper airway stimulation in a patient with prior radiation for oropharynx cancer complicated by osteoradionecrosis of the mandible.

Additive manufacturing technology in reconstructive surgery.

PURPOSE OF REVIEW: Technological advances have been part and parcel of modern reconstructive surgery, in that practitioners of this discipline are continually looking for innovative ways to perfect their craft and improve patient outcomes. We are currently in a technological climate wherein advances in computers, imaging, and science have coalesced with resulting innovative breakthroughs that are not merely limited to improved outcomes and enhanced patient care, but may provide novel approaches to training the next generation of reconstructive surgeons. RECENT FINDINGS: New developments in software and modeling platforms, imaging modalities, tissue engineering, additive manufacturing, and customization of implants are poised to revolutionize the field of reconstructive surgery. SUMMARY: The interface between technological advances and reconstructive surgery continues to expand. Additive manufacturing techniques continue to evolve in an effort to improve patient outcomes, decrease operative time, and serve as instructional tools for the training of reconstructive surgeons.

Evaluating risk factors and predicting complications in head and neck reconstructive surgery.

PURPOSE OF REVIEW: Complications in head and neck reconstructive surgery can have devastating effects. There is a tremendous body of literature examining risk factors that may predict complications in this patient population, thereby minimizing or avoiding adverse outcomes. RECENT FINDINGS: Rotational thromboelastometry may provide a mechanism to predict coagulopathy in patients undergoing microvascular reconstruction. Surveillance of serum C-reactive protein levels may provide an additional tool for early intervention in wound complications Controversy persists in the literature regarding specific risk factors and associated perioperative complications. SUMMARY: Perioperative medical and surgical complications are commonplace in the management of complex oncologic disease and attendant defect reconstructions. Potential risk factors have been examined exhaustively in the literature without a consensus being established.

Preformed vs intraoperative bending of titanium mesh for orbital reconstruction.

OBJECTIVE: The most accurate orbital reconstructions result from an anatomic repair of the premorbid orbital architecture. Many different techniques and materials have been used; unfortunately, there is currently no optimal method. This study compares the use of preformed vs intraoperative bending of titanium mesh for orbital reconstruction in 2-wall orbital fractures. STUDY DESIGN: Cadaver-based study. SETTING: University hospital. SUBJECTS AND METHODS: Preinjury computed tomography scans were obtained in 15 cadaveric heads (30 orbits). Stereolithographic (STL) models were fabricated for 5 of the specimens (10 orbits). Two wall fractures (lamina papyracea and floor) were then generated in all orbits. Surgical reconstruction was performed in all orbits using 1 of 3 techniques (10 orbits each): (1) patient-specific implant molded from the preinjury STL model, (2) titanium mesh sheet bent freehand, and (3) preformed titanium mesh. Each technique was evaluated for orbital volume correction, contour accuracy, ease of use, and cost. RESULTS: No difference in volume restoration was found between the 3 techniques. Patient-specific implants had the greatest contour accuracy, poor ease of use, and highest cost. Freehand bending implants had the poorest contour accuracy, acceptable ease of use, and lowest cost. Preformed mesh implants had intermediate contour accuracy, excellent ease of use, and low cost. CONCLUSION: All 3 techniques provide equivalent orbital volume correction. However, preformed mesh implants have many advantages based on contour accuracy, ease of use, and relative cost.

Computer-aided analysis of orbital volume: a novel technique.

OBJECTIVE: : To demonstrate the accuracy and efficiency of a novel software tool designed specifically for volumetric analysis of the orbit. METHODS: : The software was evaluated for accuracy and speed in analysis of orbital CT data sets. The analysis included: 1) intraoperator error: one operator repeatedly evaluated a single orbit multiple times. The variation in volumes was compared; 2) interoperator error: 3 operators evaluated the same orbits multiple times. The variation in volume measurements among operators was compared; 3) interscan error: one operator evaluated the volume of single orbit scanned on multiple occasions by different CT scanners. The variation in volume measurements among scans performed at different times was compared; and 4) time for analysis: one operator evaluated 52 orbits, recording the time it took to analyze each orbit. RESULTS: : Intraoperator error was 0.08 cc (95% confidence interval, 0.06-0.10). Interoperator error was 0.18 cc (95% confidence interval, 0.14-0.20). Interscan variability data showed a trend toward increasing error for repeated patient scans using different CT scanners. Average time for analysis of single orbit was 138 seconds (standard deviation = 24; range, 95-217 seconds). CONCLUSIONS: : Maxillo is an accurate and efficient tool for semiautomatic evaluation of orbital volume in nontraumatized orbits.

Pharyngeal wall differences between normal younger and older adults.

Previous research has demonstrated differences in pharyngeal size and constriction between normal younger and older adults. The distance between the larynx and the hyoid bone at rest is greater in older persons, as is the anteroposterior width of the pharynx when it is maximally expanded during swallow. In addition, pharyngeal clearing during swallow is reduced with aging. These observations suggest that the aging pharynx undergoes structural changes consistent with atrophy. The purpose of this investigation was to compare pharyngeal wall thickness at rest and when maximally constricted during swallow in younger and older adults. Videofluoroscopic swallow studies were performed on 178 normal adults. Measures of posterior pharyngeal wall thickness were determined at rest and during maximum constriction of the pharynx during a 20-ml bolus swallow. Data were subjected to analysis of variance and Student t test procedures to determine sex and age differences. We found no statistically significant differences between the men and women in either age group, and so we then pooled our data across sex. Mean pharyngeal wall thickness at rest was 0.39 cm (±0.09) in the younger group and 0.30 cm (±0.08) in the older group (p < 0.01). Pharyngeal wall thickness measured at the same point during maximum constriction was 1.08 cm (±0.34) in the younger group and 0.92 cm (±0.36) in the older adults (p<0.01). Our data suggest that the posterior pharyngeal wall is thinner and does not constrict to the same extent in older subjects compared with younger individuals. These findings contribute to our understanding of differences in pharyngeal strength, swallowing efficiency, and safety associated with aging.

Pediatric lipoblastoma in the head and neck: a systematic review of 48 reported cases.

BACKGROUND: Lipoblastoma is an exceedingly rare cause of pediatric head and neck masses. There have been 47 cases previously reported in the English literature. We present an additional case and review of the available literature on this rare neoplasm. OBJECTIVE: To review and assess the current published literature regarding the efficacy of preserving neurovascular structures in the surgical management of pediatric lipoblastoma. METHODS: Literature analysis of case reports was performed. MEDLINE was searched for the terms "neonatal lipoblastoma", "lipoblastomatosis", and "benign lipoblastoma". Results in the English literature were mined for relevant clinical data when available. The citations of case reviews found were searched to find additional cases. RESULTS: Including our new case, a total of 48 cases of head and neck lipoblastoma have been reported in the English literature within 23 manuscripts. Four manuscripts presented cases series (Evidence Based Medicine Level 4) and 19 were case reports (Level 5). The median sample size was 1 (range 1-4). For those 14 articles (N=23 cases) reporting follow-up, the median follow-up duration was 22 months. Male to female ratio was 2.1:1 with an average age at presentation of 2.1 years (range: newborn to 12 years). Lesions ranged from 3 to 12 cm in longest diameter. Recurrence was seen in 27% of patients in which there was at least 1-year follow-up. The most common presenting symptoms were painless enlarging neck mass (53%, 17/32) and respiratory distress (12%, 4/32). An exact binomial sign test indicated that most authors recommend conservative complete excision with preservation of vital structures with 10 of 11 authors giving a stance supporting conservative surgical resection, p=.012. CONCLUSIONS: Our findings suggest that although total excision is ideal and curative, subtotal resection may be a viable treatment alternative for lipoblastoma of the head and neck. This tumor presents a clinical challenge and should be considered in infants presenting with a cervical mass. It is difficult to differentiate from the much more common lymphangioma on clinical and radiological examination. Additionally, the potential for rapid growth and adhesion to neurovascular tissue makes surgical resection arduous. Nonetheless, recurrence rates for head and neck lipoblastomas are similar to those rates observed elsewhere in the body.

Validation of the pharyngeal squeeze maneuver.

OBJECTIVE: The pharyngeal squeeze maneuver (PSM) is a surrogate measure of pharyngeal strength on endoscopy. The validity of this measure has not been reported. The purpose of this investigation was to evaluate the validity of the PSM. STUDY DESIGN: Case series with planned data collection. SUBJECTS AND METHODS: Simultaneous endoscopic and fluoroscopic swallow evaluations were performed on a cohort of individuals with dysphagia. The PSM was compared to a validated measure of pharyngeal strength, the pharyngeal constriction ratio (PCR). An elevated PCR indicates a weakened pharynx. RESULTS: The mean PCR for subjects with an intact PSM was 0.06 (+/- 0.08), compared to a mean PCR of 0.31 (+/- 0.20) for individuals with an absent PSM. The PCR was significantly higher, indicating a weaker pharynx, in persons with an absent PSM (P < 0.001). CONCLUSIONS: The PCR is elevated in persons with a diminished pharyngeal squeeze. These data suggest the pharyngeal squeeze maneuver is a valid surrogate measure of pharyngeal motor integrity.

Comparison of 3 optical navigation systems for computer-aided maxillofacial surgery.

OBJECTIVE: To compare the accuracy of 3 computer-aided surgery systems for maxillofacial reconstruction. DESIGN: Evaluation of 3 computer-aided surgery systems: StealthStation, VectorVision, and Voxim. SETTING: The University of California, Davis, Department of Otolaryngology computer-aided surgery laboratory. PARTICIPANTS: Four fresh cadaveric heads. MAIN OUTCOME MEASURE: Mean target registration error. RESULTS: The StealthStation was the most accurate (mean [SD] target registration error, 1.00 [0.04] mm), followed by VectorVision (1.13 [0.05] mm) and then Voxim (1.34 [0.04] mm). All values met statistical significance (P < .05). CONCLUSIONS: Measurable accuracy differences were found among the navigation systems evaluated. The StealthStation was the most accurate. However, the differences are small, and the clinical significance for maxillofacial reconstruction is negligible.

Computer applications in facial plastic and reconstructive surgery.

PURPOSE OF REVIEW: Computer applications in facial plastic and reconstructive surgery continue to evolve as image-guided surgical technology and software applications improve. Surgeons use these technological advances in order to simplify complex and historically challenging reconstructive issues. This paper reviews the recent literature pertaining to advances in computer-aided presurgical planning and intraoperative navigation. RECENT FINDINGS: Although many different computer-aided surgical applications have previously been described, the recent literature focuses on orbital, midface and mandibular reconstruction. These studies highlight primary and secondary repair of complex maxillofacial trauma using computer software platforms for analysis of computed tomography data, presurgical planning, and intraoperative navigation. SUMMARY: Computer-assisted facial reconstructive surgery is an area which continues to evolve. The current technology is best served in the repair of complex primary or secondary posttraumatic deformities. Congenital and oncologic reconstructive applications, however, are growing rapidly. While computer-aided surgery has historically been limited to tertiary care centers, easy access to intraoperative navigation systems and more user friendly software applications make these techniques more accessible to a greater number of surgeons.