Faculty Bibliography

OBJECTIVE: Common peroneal nerve (CPN) paresis or paralysis presents with weakness of the toe extensors as well as of the ankle dorsiflexors and evertors, causing foot drop and hypesthesia or paresthesia in the CPN distribution. Previous studies have shown associations with weight loss and leg crossing. Although CPN neuropathy has been described in cancer patients, it has not been described in head and neck cancer (HNC) patients specifically. Our objective was to describe a series of patients who developed CPN neuropathy during the course of their disease. MATERIALS AND METHODS: A retrospective review of the charts of patients with HNC and CPN neuropathy who were seen at our institution between 1995 and 2004 was performed. RESULTS: Four HNC patients with CPN neuropathy were identified. All had significant weight loss. One patient became symptomatic before treatment, 2 patients became symptomatic during treatment, and 1 patient developed foot drop 4 years after treatment when his free jejunal flap developed a stricture. Two patients had electrodiagnostic study findings that revealed conduction block at the fibular head and denervation of peroneal innervated muscles. Imaging studies revealed no evidence of metastatic disease in the lumbosacral region. All 4 patients improved after weight gain. CONCLUSIONS: Common peroneal nerve neuropathy may be seen in HNC patients. The CPN may be susceptible in weight loss because of the associated loss of subcutaneous tissue, which cushions the nerve from the fibular head. Consideration should be given to prevention, appropriate neurologic consultation, and patient counseling

BACKGROUND:Recently, balloon catheter (BC) dilatation of paranasal sinus ostia has been introduced. In this procedure, a balloon-tipped catheter is placed across a sinus ostium over a flexible wire under fluoroscopic guidance, and inflation of the balloon enlarges the ostium. Some rhinologists have criticized this procedure for its failure to remove tissue and bone, especially in the setting of sinonasal polyposis. This project seeks to develop strategies for incorporating BC technology into standard functional endoscopic sinus surgery procedures. METHODS:Endoscopic sinus dissection of three human cadaveric heads was performed with conventional instruments supplemented by lacrimal duct BCs (LacriCATH; Quest Medical, Allen, TX). No fluoroscopy was used. Each dissection was videotaped for later review. RESULTS:For frontal recess dissection, these steps were performed under endoscopic visualization: (1) passage of the BC between frontal recess partitions, (2) BC inflation, and (3) removal of fractured frontal recess partitions with conventional instruments. This approach was used successfully in each frontal recess. Under endoscopic visualization, a BC was passed into the sphenoid ostium and inflated; this maneuver successfully dilated each sphenoid ostium. It was not feasible to reliably pass the BC through the natural maxillary ostium. Each BC was inflated to 8 atm for 30 seconds. No evidence of orbital or skull base injury was noted. No fluoroscopy was used. CONCLUSION/CONCLUSIONS:BCs may be used as adjunctive instrumentation for endoscopic sinus dissection without fluoroscopy. This strategy warrants additional technical and clinical development.

OBJECTIVE: To analyze an optimal management protocol for patients 65 years or older at the time of acoustic neuroma diagnosis. STUDY DESIGN: Retrospective case review. SETTING: Tertiary care hospital. PATIENTS: Two hundred sixteen patients with acoustic neuroma 65 years or older at time of diagnosis. INTERVENTION: Patients with smaller tumors (<2.5 cm) were followed with serial magnetic resonance imaging. If significant growth occurred, they were treated with surgery. Surgery was performed at initial diagnosis on patients with larger tumors or in selected patients for hearing preservation. Stereotactic radiotherapy was performed for poor surgical candidates and for patient choice. OUTCOME MEASURES: Measurement of acoustic neuroma growth and tabulation of complications. RESULTS: One hundred fourteen patients were initially managed by observation, 80 with surgery, and 3 with radiation therapy, with an average follow-up of 35.4 months. For patients in the observation group, average tumor growth was 1.2 mm/yr. Thirty-two patients required crossover to surgery or radiotherapy due to tumor growth (average growth, 4.1 versus 0.3 mm/yr for those remaining in the observation group). One of the patients in the observation group had a complication (0.9%). CONCLUSION: Management of acoustic neuromas in elderly patients can be based on size and 'biological age' criteria. Surgical treatment can safely be reserved for the few patients who have significant tumor growth

Classic rhizomelic chondrodysplasia punctata is a rare, autosomal, recessively inherited disorder that is characterized by proximal shortening of the limbs, punctuate calcifications of the epiphyses, cataracts, developmental delay, and early lethality. A distinctive biochemical profile is characteristic for each of the several defects of peroxisomal metabolism. Recently, cases have been described that were not associated with peroxisomal dysfunction. These cases were found to be secondary to teratogen exposure or maternal conditions. Since 1993, there have been 9 reported cases of neonates with rhizomelic chondrodysplasia punctata who were born to mothers with connective tissue disease. We followed a newborn boy with features suggestive of rhizomelic chondrodysplasia punctata whose biochemical studies failed to demonstrate a defect in either plasmalogen or cholesterol biosynthesis. His mother developed systemic lupus erythematosus 8 months after delivery. This case is compared with the previously reported 9 cases from the literature and is instructive in demonstrating a lesser known effect of maternal autoantibodies on the fetus.

OBJECTIVES: To examine the conclusions and possible misinterpretations that may or may not be drawn from the 'outcome-matching method,' a study design recently used in the cochlear implant literature. In this method, subject groups are matched not only on potentially confounding variables but also on an outcome measure that is closely related to the outcome measure under analysis. For example, subjects may be matched according to their speech perception scores in quiet, and their speech perception in noise is compared. DESIGN: The present study includes two components, a simulation study and a questionnaire. In the simulation study, the outcome-matching method was applied to pseudo-randomly generated data. Simulated speech perception scores in quiet and in noise were generated for two comparison groups, in two imaginary worlds. In both worlds, comparison group A performed only slightly worse in noise than in quiet, whereas comparison group B performed significantly worse in noise than in quiet. In Imaginary World 1, comparison group A had better speech perception scores than comparison group B. In Imaginary World 2, comparison group B had better speech perception scores than comparison group A. The outcome-matching method was applied to these data twice in each imaginary world: 1) matching scores in quiet and comparing in noise, and 2) matching scores in noise and comparing in quiet. This procedure was repeated 10,000 times. The second part of the study was conducted to address the level of misinterpretation that could arise from the outcome-matching method. A questionnaire was administered to 54 students in a senior level course on speech and hearing to assess their opinions about speech perception with two different models of cochlear implant devices. The students were instructed to fill out the questionnaire before and after reading a paper that used the outcome-matching method to examine speech perception in noise and in quiet with those two cochlear implant devices. RESULTS: When pseudorandom scores were matched in quiet, comparison group A's scores in noise were significantly better than comparison group B's scores. Results were different when scores were matched in noise: in this case, comparison group B's scores in quiet were significantly better than comparison group A's scores. Thus, the choice of outcome measure used for matching determined the result of the comparison. Additionally, results of the comparisons were identical regardless of whether they were conducted using data from Imaginary World 1 (where comparison group A is better) or from Imaginary World 2 (where comparison group B is better). After reading the paper that used the outcome-matching method, students' opinions about the two cochlear implants underwent a significant change even though, according to the simulation study, this opinion change was not warranted by the data. CONCLUSIONS: The outcome-matching method can provide important information about differences within a comparison group, but it cannot be used to determine whether a given device or clinical intervention is better than another one. Care must be used when interpreting the results of a study using the outcome-matching method

Solitary fibrous tumors are benign neoplasms of mesenchymal origin. They usually arise from the visceral or parietal pleura and peritoneum, although they have been found in many areas throughout the body. We report a case of solitary fibrous tumor of the parapharyngeal space. Microscopically, the tumor contained spindle cells with areas of marked hypercellularity without a definitepattern. Consistent with a benign lesion, there were few mitoses and no necrosis. The tumor cells stained strongly positive for CD34 and vimentin. At the 2-year follow-up, the patient was well and free of local and/or distant disease

The cortex is thought to be the primary site of sensory plasticity, particularly during development. Here, we report that large-scale reorganization of the mouse auditory midbrain tonotopic map is induced by a specific sound-rearing environment consisting of paired low- (16 kHz) and high-frequency (40 kHz) tones. To determine the potential for plasticity in the mouse auditory midbrain, we used manganese-enhanced MRI to analyze the midbrain tonotopic maps of control mice during normal development and mice reared in the two-tone (16 + 40 kHz) environment. We found that the tonotopic map emerged during the third postnatal week in normal mice. Before 3 weeks, a larger percentage of auditory midbrain responded to each of the suprathreshold test frequencies, despite the fact that the primary afferent projections are in place even before hearing onset. By 3 weeks, the midbrain tonotopic map of control mice was established, and manganese-enhanced MRI showed a clear separation between the 16- and 40-kHz responses. Two-tone rearing dramatically altered the appearance of these discrete frequency-specific responses. A significant volume of the auditory midbrain became responsive to both rearing frequencies, resulting in a large-scale reorganization of the tonotopic map. These results indicate that developmental plasticity occurs on a much greater scale than previously appreciated in the mammalian auditory midbrain

OBJECTIVE: Surgical techniques for parotid gland neoplasm removal have been shaped over the years by the importance of the gland's relationship with the facial nerve, histologic behavior of parotid tumors, and recurrence rates from specific techniques. Parotidectomy with facial nerve dissection has become the procedure of choice in removal of parotid gland neoplasms because of the resulting low recurrence rate. However, these more comprehensive dissections can cause significant postoperative complications, some cosmetically devastating. We propose that a more limited dissection yields a similar low recurrence rate but with less risk of complications. STUDY DESIGN: Retrospective case series. METHODS: A retrospective review of the clinical outcomes and pathology of 27 patients who underwent extracapsular dissection for parotid gland neoplasms. RESULTS: All tumors were located in the superficial lobe of the parotid gland and size of the masses ranged from 4.0 to 1.0 cm (mean 2.4 cm) in diameter. Pathology of the parotid tumors consisted of 11 pleomorphic adenomas, six Warthin's tumors, six benign epithelial cysts, one sarcoid lesion, two lymphoid hyperplasia, and one Kaposi's sarcoma. There were no cases of capsular rupture. There was no temporary or permanent facial paralysis and no incidence of Frey's syndrome. One patient developed a sialocele, which was aspirated and resolved after 3 months. There were no recurrences with follow-up times between 5 months and 6 years (mean 41 mo). CONCLUSION: We advocate extracapsular dissection for benign parotid neoplasms because of the acceptable recurrence rates with limited complications as compared to superficial parotidectomy