The facial nerve. Current trends in diagnosis, treatment, and rehabilitation.

Facial paralysis is a potentially devastating disorder with numerous implications. Multiple entities must be considered in its etiology, and recent advances in microbiology, radiographic imaging, electrodiagnostic testing, and microsurgery have provided great insight into the pathophysiology, diagnosis, treatment, and rehabilitation of the facial nerve. Recent DNA PCR testing has shed new insight into the potential cause for Bell's palsy. This article focuses on the evaluation, differential diagnosis, medical treatment, and rehabilitation of facial nerve pathology with primary emphasis on facial paralysis. Surgical management is also discussed, including reanimation of the paralyzed face.

Facial nerve outcome in lateral skull base surgery for benign lesions.

OBJECTIVE: To statistically identify factors most important in affecting CN7 outcome in lateral skull base surgery for benign lesions. STUDY DESIGN: A retrospective review of 217 nonmalignancy lateral skull base procedures from 1970 to 1995 at the Otology Group in Nashville. METHODS: Charts were reviewed for epidemiology, histopathology, staging, type of CN7 mobilization (none, short, long, severance with reanastomosis, and resection), preoperative and postoperative CN7 function, surgery performed, and survival. RESULTS: Average House-Brackman (HB) scores for mobilizations were as follows: short, 1.65: long, 2.74: and grafting, 4.33. Factors found to affect outcome in a statistically significant fashion were preoperative HB score, staging, type of CN7 manipulation, and surgical approach. Meningiomas were found to have a worse outcome than glomus tumors. CONCLUSIONS: Complete resection of tumors should be performed with minimal manipulation of the facial nerve based on regional anatomy and tumor anatomy.

Brain herniation into the middle ear and mastoid: concepts in diagnosis and surgical management.

OBJECTIVE: To review the occurrence characteristics of and clinical repair experience with brain herniation in to the middle ear and mastoid from 1970-1995. STUDY DESIGN: Retrospective chart/case review. SETTING: Private Otology/Neurotology referral practice. PATIENTS: Thirty-five patients with temporal bone brain herniation diagnosed and treated from 1970-1995. INTERVENTION: Diagnosis confirmed by CT and/or MRI. Treatment was surgical. MAIN OUTCOME MEASURES: Success of surgical repair of the problem in a large experience with follow-up of up to 180 months (mean, 48.7 months). RESULTS: Diagnosis is most effectively made by both (computed tomography (CT) and magnetic resonance imaging (MRI). In this series diagnosis was accurate in 89% with MRI. Primary repair was successful in all but three patients, two of whom required a second repair. One was unreconstructable. CONCLUSIONS: Temporal bone encephaloceles occur after ear surgery and in chronic otitis media. Prompt and effective surgical repair is successful and integral to complication avoidance.

Management of acoustic neuroma in the elderly population.

OBJECTIVE: Ongoing controversy regarding the optimal treatment of acoustic neuromas in the elderly population has prompted us to examine the our experience in order to arrive at a treatment algorithm. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: The records of 48 elderly patients ranging from age 70 to 90 years with acoustic tumors were reviewed. INTERVENTIONS: In 34 cases, tumor size was followed through serial imaging for a mean 28.5 months (range 5-108 months). Eight of these patients subsequently required surgery for significant tumor growth. An additional 12 patients were managed surgically from the time of diagnosis. MAIN OUTCOME MEASURE: The natural history of acoustic neuromas in the elderly population. RESULTS: The mean tumor growth rate for the watched group was 0.29 cm/y. Fifteen patients demonstrated no growth whereas accelerated growth was noted in eight cases. Ten patients with tumors confined to the internal auditory canal demonstrated an average growth rate of only 0.06 cm/y over a mean interval of 38 months. For the surgically treated group, the mean tumor size at the time of resection was 2.8 cm. Resection was described as complete in 17 cases and near-total in three cases. Perioperative complication rates and facial nerve results were comparable to our figures for all age groups. There was one perioperative death. CONCLUSIONS: Elderly patients with small acoustic neuromas should be offered a trial of observation. When significant tumor growth, size, or neurologic deterioration are demonstrated, early surgical intervention is required to avoid complications associated with the removal of larger tumors.

Endoscopic Zenker's diverticulotomy (Dohlman procedure): forty cases reviewed.

Pharyngoesophageal diverticula, first described in 1769, occur in an area of natural weakness between the inferior pharyngeal constrictor muscles of the pharynx and the cricopharyngeus muscle. The cause of these acquired diverticula is controversial, although most likely it is related to cricopharyngeus muscle dysfunction. Treatment is directed toward correcting the underlying sphincter dysfunction and managing the diverticulum. Endoscopic diverticulotomy requires division of the cricopharyngeus and the common wall between the esophagus and diverticulum, a technique popularized by Dohlman. We reviewed the results of 40 endoscopic diverticulotomy patients, ranging in age from 46 to 88 years, many of whom had significant existing comorbidities. The mean size of the diverticula was 4.1 cm, mean surgery time was 41 minutes, and mean hospital stay was 4.5 days. Thirty-seven of 40 patients, including 3 whose previous external procedure was not successful, returned to a regular diet, reported no regurgitation and were satisfied with the procedure. Complications in order of occurrence were pneumomediastinum (4 patients), urinary tract infection (2), upper respiratory tract infection (2), and lip laceration (1). Our results compare favorably with those of external approaches. The technique should be considered safe, expedient, and effective, particularly in patients with existing comorbidities.

Lateral skull base surgery: the otology group experience.

Lateral skull base surgery has remained the surgical frontier of new developments in the treatment of lesions heretofore difficult to access. Examination of surgical results stimulates technical innovation and provides an intervention risk-benefit ratio assessment for particular lesions useful in management planning. With this in mind, we report the updated collective experience with lateral skull base surgery at the Otology Group over the past 20 years. Two hundred ninety-eight patients underwent surgical intervention for lateral skull base lesions. In 81 patients these lesions were malignant; in 217, benign. Of the benign lesions, 165 were glomus tumors: 139 glomus jugulare, 19 glomus vagale, and 7 glomus tympanicum. The remainder comprised 21 menigniomas, 14 neuromas, two neurofibromas, and a small group of much rarer entities. The philosophy of surgical approach, results, and follow-up are discussed.

Pediatric neurotologic skull base surgery.

The objectives of neurotologic skull base surgery are complete resection of the lesion and high-grade function following surgery. There is a perception that these goals are more difficult to achieve in children than in adults. Skull base disease in children and adolescents is rare. Of the 292 skull base tumors treated from 1970 to 1995 by The Otology Group in Nashville, 15 were in patients 21 years of age or younger, with only 5 patients under 10 years old. In this retrospective study, the authors review these 15 cases and compare them to their adult series. The pathology encountered in the 15 young patients with skull base tumors included 8 glomus lesions and 4 schwannomas. In these patients, 13 tumors occurred sporadically, and 2 tumors were related to neurofibromatosis type 2. Advanced-stage disease and malignancy were prevalent in this younger patient group. All patients underwent excision of their skull base tumor, with one procedure considered a subtotal resection. As compared with an adult glomus tumor series, postoperative cranial nerve function and complication rates were generally worse in the young glomus patients. However, postoperative function and complications were consistent with the extensive procedures required for the treatment of advanced disease. Despite the advances that have been made in imaging and treatment modalities, this study illustrates the need for more timely diagnosis in younger patients with skull base tumors.

Anterior facial nerve rerouting in cranial base surgery: a comparison of three techniques.

Anterior rerouting of the facial nerve is a maneuver designed to enhance exposure of the jugular foramen and carotid canal during resection of cranial base tumors. Our clinical impression is that the degree of additional exposure afforded by moving the facial nerve varies considerably according to both anatomic variations and the technique used. Three possible techniques exist based on the extent of facial nerve mobilization and point of rotation: canal wall up-second genu pivot point (CWU-2G); canal wall down-second genu pivot point (CWD-2G); and canal wall down-first genu pivot point (CWD-IG). We anatomically studied 20 human cadaver heads to establish clinically relevant guidelines for the selective use of these techniques. At the level of the dome of the jugular bulb, the facial nerve mobilized anteriorly a mean of 4.2 mm for CWU-2G, 10 mm for CWD-2G, and 14 mm for CWD-1G. Detailed analysis of numerous measurements and rotation angles suggests that the typical exposure afforded by the various rerouting techniques is as follows: CWU-2G, complete exposure of the jugular bulb; CWD-2G, exposure of the jugular bulb and a mean of 6 mm of the posterior aspect of the carotid artery; and CWD-IG, exposure of the jugular bulb and entire carotid genu. Minimizing the amount of facial nerve manipulation needed to achieve sufficient surgical exposure helps optimize postoperative functional status.

Bell's palsy treatment with acyclovir and prednisone compared with prednisone alone: a double-blind, randomized, controlled trial.

In a double-blind study, we compared the final outcome of 99 Bell's palsy patients treated with either acyclovir-prednisone (53 patients) or placebo-prednisone (46 patients). For patients receiving acyclovir, the dosage was 2,000 mg (400 mg 5 times daily) for 10 days. Electrical tests included electroneurography and the maximal stimulation test. Univariate comparisons of outcome and electrical tests between the two groups were made with chi 2 analysis, Fisher's exact test, and t-tests. The outcome in acyclovir-prednisone-treated patients was superior to that in placebo-prednisone-treated patients. Treatment with acyclovir-prednisone was statistically more effective in returning volitional muscle motion (recovery profile of 10; p = .02) and in preventing partial nerve degeneration (p = .05) than placebo-prednisone treatment. The t-tests indicated that the recovery profile and index means were significantly better for the acyclovir-treated group (recovery profile t = 1.99, p = .051; recovery index t = 2.10, p = .040). We conclude that acyclovir-prednisone is superior to prednisone alone in treating Bell's palsy patients and suggest that herpes simplex is the probable cause of Bell's palsy.

Relation between age and head and neck cancer recurrence after surgery: a multivariate analysis.

Recent reports have described an increase in squamous cell carcinoma of the upper aerodigestive tract in young adults. As the preponderance of epidemiologic data exists for the population between 50 and 70 years of age, controversy has developed regarding the clinical course of head and neck cancer in youth. Some authors advocate more aggressive management, calling attention to the lack of "classic" predisposing factors and suggesting genetic disorders or immunodeficiency. Basic science researchers have reported greater DNA fragility, sensitivity to carcinogens, and altered immune responses in young patients with carcinoma. To further elucidate the clinical aspects of this controversy, we performed a retrospective review using multivariate analysis to determine factors that affect recurrence. After screening 820 charts, 155 patients were found who met strict entrance criteria to the study. The patients were separated into five age groups, and 16 clinical variables were collected on each patient. Cox proportional hazards modeling revealed no significantly higher likelihood of recurrence in the 15- to 39-year-old age group. The model did find that metastatic adenopathy was predictive of recurrence (p = 0.034). The overall model further suggested a trend toward higher relative risk of recurrence in the middle-aged groups (p = 0.0541). In our review of the English biomedical literature, this is the first study to directly compare the outcome of young head and neck cancer patients with that of old patients using multivariate analysis. Future research is indicated in developing precise outcome predictions according to TNM staging, aneuploidy status, and DNA fragility in young patients. Efforts at limiting carcinogen exposure should continue.

Ventricular dysphonia: a profile of 40 cases.

Ventricular dysphonia is a poorly understood disorder involving ventricular fold participation during phonation. A population of ventricular dysphonia patients was evaluated using phonatory function studies such as laryngovideostroboscopy, advanced acoustic analysis, and electroglottography to identify shared epidemiologic characteristics and to discuss possible neuromuscular mechanisms and causes. Forty patients with ventricular dysphonia were studied and epidemiologic, acoustic, and histologic data were analyzed. In almost all cases, the authors found abnormalities affecting the glottis caused by a related medical condition. The abnormalities included true vocal cord (TVC) aperiodicity in 100% of the patients, TVC asymmetry in 65%, a laryngeal mass or foreign body (usually Teflon) in 35%, TVC erythema or edema in 32.5%, and TVC bowing in 22.5%. Ventricular dysphonia seems to be primarily a compensatory mechanism for glottic dysfunction. Therapy is based on identifying and correcting the underlying abnormalities. Laryngovideostroboscopy is a particularly important tool in examining chronic dysphonia.

Laryngeal airway resistance. The relationships of airflow, pressure, and aperture.

In the surgical treatment of the paralyzed larynx, a compromise often needs to be made between an orifice size needed to preserve voice and that needed for adequate inspiratory airflow rates. To assess the negative pressures needed to generate normal airflows across a narrowed vocal cord aperture, we measured pressure and flow changes across cadaveric larynges while altering aperture size. Best-fit quadratic equations for each aperture area selected were derived and showed that if the aperture were 0.5 cm2 or less, the resistance to normal breathing would be significantly increased. Aperture sizes of 0.67 cm2 or greater are not associated with such an increase in resistance.