Faculty Bibliography

The basic principle of anterior skull base surgery is to provide adequate exposure to enable three dimensional resection of skull base tumors. Negative surgical margins, which is within the control of surgeon, is the principle prognostic factor in anterior skull base tumors. Open skull base approaches is the standard of care for malignant anterior skull base tumors. Benign lesions may be resected by alternate minimally invasive approaches. Advances in anterior skull base surgery, in particular the facial translocation approaches allows wide exposure of the tumors with minimal retraction of the brain. The outcome of anterior skull base tumors have steadily increased over the years with disease free survival comparable to other malignant neoplasm of the head and neck region. This review described various surgical approaches and pertaining anatomy and pathology of anterior skull base tumors.

BACKGROUND: The objective of this study was to determine the relative efficacy of different methods of pathologic evaluation of sentinel lymph nodes. METHODS: In this prospective study, sentinel nodes were evaluated for occult metastasis using frozen section, imprint-cytology, hematoxylin-eosin staining, serial step sectioning (SSS) with hematoxylin-eosin, and immunohistochemistry (IHC). Metastases were classified into macrometastasis (>2.0 mm), micrometastasis (0.2 mm-2.0 mm), isolated tumor cells (<0.2 mm). RESULTS: Occult metastasis was detected in 20 of 80 patients. Frozen section and imprint cytology identified metastasis in 10 of 20 patients, hematoxylin-eosin stain in 13 patients; SSS upstaged the disease in a further 7 patients (9%). Frozen section detected macrometastasis in 7 of 8 cases but failed to detect smaller metastases (missed micrometastasis in 4 of 7 and isolated tumor cells in 5 of 5). SSS upstaged the disease by 10%, and sensitivity and negative predictive value of SSS with hematoxylin-eosin stain were 90% and 97%, respectively. CONCLUSION: Frozen section and imprint cytology are not effective in identifying occult metastasis. IHC and SSS are required to identify micrometastasis and isolated tumor cells.

Tensor Fascia Lata muscle and musculocutaneous flap has been used in the past for reconstruction of trunk defects and also as a free flap for soft tissue reconstruction elsewhere in the body. Transferring the iliac crest along with the muscle as a free flap has been described earlier, reported for bridging calcaneal defect and small mandibular defects. The use of this flap as a source of free vascularised bone has not been widely practised since these initial few reports. Anatomical studies were carried out to assess the feasibility of using this flap for reconstructing maxillary and other head and neck defects, following which it was successfully used for these indications. The preliminary report describes the flap anatomy, method of harvest and its potential uses in head and neck reconstruction.

OBJECTIVES/HYPOTHESIS: To identify contemporary indications, treatment principles, technique, injection materials, complications, and success rates of vocal fold injection augmentation. STUDY DESIGN: Multi-institutional retrospective review. METHODS: Records of patients undergoing injection augmentation at seven university medical centers from July 2007 through June 2008 were reviewed for information regarding diagnosis, unilateral or bilateral injection, route of injection, anesthesia, treatment site (office or operating room), material used, reason for technique selected, and technical success. RESULTS: In 12 months, 460 injections were performed, 236 (51%) in awake, unsedated patients, and 224 (49%) under general anesthesia. Indications included vocal fold paralysis (248; 54%), paresis (97; 21%), atrophy (68; 15%) and scar (47; 10%). Scar was more likely to be treated in the operating room (P = .000052). In awake patients, 112 (47%) injections were performed by transcricothyroid approach, 55 (23%) by peroral approach, 49 (21%) by transthyrohyoid membrane approach, and 20 (8%) by transthyroid cartilage approach. Neither technical success rate (99% vs. 97%) nor complication rate (3% vs. 2%) differed between awake and asleep techniques. The most common materials in the clinic setting were methylcellulose (35%), bovine collagen (28%), and calcium hydroxylapatite (26%); in the operating room these were calcium hydroxylapatite (36%) and methylcellulose (35%). Calcium hydroxylapatite was more likely to be used under general anesthesia (P = .019). Five-year data show that the use of injection in the awake patient rose from 11% to 43% from 2003 to 2008. CONCLUSIONS: Injection augmentation remains a safe, effective, and clinically practical treatment with a high rate of success, whether performed in the awake or asleep patient. The rapid adoption of awake injection over the past 5 years speaks to its clinical utility. Complication rates are low and equivalent to those under general anesthesia. Otolaryngologists continue to use a variety of techniques and materials to treat a range of conditions of glottic insufficiency.

Cochlear implant (CI) users' spectral resolution is limited by the number of implanted electrodes, interactions between the electrodes, and the underlying neural population. Current steering has been proposed to increase the number of spectral channels beyond the number of physical electrodes, however, electric field interactions may limit CI users' access to current-steered virtual channels (VCs). Current focusing (e.g tripolar stimulation) has been proposed to reduce current spread and thereby reduce interactions. In this study, current steering and current focusing were combined in a four-electrode stimulation pattern, i.e quadrupolar virtual channels (QPVCs). The spread of excitation was measured and compared between QPVC and Monopolar VC (MPVC) stimuli using a forward masking task. Results showed a sharper peak in the excitation pattern and reduced spread of masking for QPVC stimuli. Results from the forward masking study were compared with a previous study measuring VC discrimination ability and showed a weak relationship between spread of excitation and VC discriminability. The results suggest that CI signal processing strategies that utilize both current steering and current focusing might increase CI users' functional spectral resolution by transmitting more channels and reducing channel interactions.

This study investigated cochlear implant (CI) users' ability to perceive pitch cues from time-varying virtual channels (VCs) to identify pitch contours. Seven CI users were tested on apical, medial, and basal electrode pairs with stimulus durations from 100 to 1000 ms. In one stimulus set, 9 pitch contours were created by steering current between the component electrodes and the VC halfway between the electrodes. Another stimulus set only contained 3 pitch contours (flat, falling, and rising). VC discrimination was also tested on the same electrodes. The total current level of dual-electrode stimuli was linearly interpolated between those of single-electrode stimuli to minimize loudness changes. The results showed that pitch contour identification (PCI) scores were similar across electrode locations, and significantly improved at longer durations. For durations longer than 300 ms, 2 subjects had nearly perfect 9-contour identification, and 5 subjects perfectly identified the 3 basic contours. Both PCI and VC discrimination varied greatly across subjects. Cumulative d(') values for VC discrimination were significantly correlated with 100-, 200-, and 500-ms PCI scores. These results verify the feasibility of encoding pitch contours using current steering, and suggest that identification of such pitch contours strongly relies on CI users' sensitivity to VCs.

AIM: The aim of this unregistered evidence-based systematic review was to determine the state and quality of evidence on the effects of oral motor exercises (OME) on swallowing physiology, pulmonary health, functional swallowing outcomes, and drooling management in children with swallowing disorders. METHOD: A systematic search of 20 electronic databases was completed to identify relevant peer-reviewed literature published in English between 1960 and 2007. Experimental or quasi-experimental design studies examining OME as a treatment for children with swallowing disorders were appraised for methodological quality by two assessors and reviewed by a third. RESULTS: Sixteen studies of varying methodological quality were included. No study examining the effects of OME on pulmonary health in children was identified. The included studies incorporated a wide variety of OME, and mixed findings were noted across all of the outcomes targeted in this review. INTERPRETATION: Based on the results of this evidence-based systematic review, there is insufficient evidence to determine the effects of OME on children with oral sensorimotor deficits and swallowing problems. Well-designed studies are needed to provide clinicians with evidence that can be incorporated into the preferences of the client and the clinicians' knowledge of anatomy, physiology, and neurodevelopment in the management of this group of children.

BACKGROUND: Functional outcomes assessment has become increasingly important in informing treatment decisions in the area of head and neck cancer. However, consistency of assessment methods across studies has been lacking. For the literature to inform clinical decision making, consensus regarding outcomes measurements is necessary. OBJECTIVE: The Head and Neck Research Network (HNRN) was founded in January 2008 to become a conduit for high-quality research in the area of functional outcomes in patients with head and neck defects. The present study surveyed experts in functional outcomes assessment to determine what are considered the most important tools for assessing speech and swallowing and what background patient characteristics are important to capture. DESIGN, PARTICIPANTS, AND MEASURES: Respondents to the online survey included 54 participants with a background in speech-language pathology, with the majority of respondents from the United States, Canada, and the United Kingdom. RESULTS AND CONCLUSIONS: The results from the survey indicated that clinicians consider both subjective and objective measures as important to use when assessing function. More advanced technical tools were often rated as less important; however, it also was noted that clinicians were most often not able to access these tools or were unfamiliar with them.