Idiopathic sudden sensorineural hearing loss: A critique on corticosteroid therapy.

Idiopathic sudden sensorineural hearing loss (ISSNHL) is a condition affecting 5-30 per 100,000 individuals with the potential to significantly reduce one's quality of life. The true incidence of this condition is not known because it often goes undiagnosed and/or recovers within a few days. ISSNHL is defined as a ≥30 dB loss of hearing over 3 consecutive audiometric octaves within 3 days with no known cause. The disorder is typically unilateral and most of the cases spontaneously recover to functional hearing within 30 days. High frequency losses, ageing, and vertigo are associated with a poorer prognosis. Multiple causes of ISSNHL have been postulated and the most common are vascular obstruction, viral infection, or labyrinthine membrane breaks. Corticosteroids are the standard treatment option but this practice is not without opposition. Post mortem analyses of temporal bones of ISSNHL cases have been inconclusive. This report analyzed ISSNHL studies administering corticosteroids that met strict inclusion criteria and identified a number of methodologic shortcomings that compromise the interpretation of results. We discuss the issues and conclude that the data do not support present treatment practices. The current status on ISSNHL calls for a multi-institutional, randomized, double-blind trial with validated outcome measures to provide science-based treatment guidance.

Axonal numbers in the greater auricular nerve: is there enough to go round?

HYPOTHESIS: Does the greater auricular nerve (GAN) have an appropriate number of myelinated axons for use as an interposition graft for the facial nerve? BACKGROUND: Previous studies have suggested that the GAN has a suitable cross-sectional and fascicular area for use as an interposition graft for the facial nerve. In this study, counts of myelinated axons in the GAN have been undertaken to assess, at a microscopic level, its suitability as such a graft. METHODS: Six GANs were examined, and the total myelinated axonal counts and axonal density per square millimeter of fascicular area were calculated. These counts were compared with previous studies on the facial nerve. RESULTS: Axonal density per square millimeter was comparable between greater auricular and facial nerves. However, there were significantly lower numbers of myelinated axons in the GAN compared with the published facial nerve data. CONCLUSION: The findings support the concept of "doubling over" the GAN to act as an appropriate interpositional facial nerve graft when there is a size mismatch between the two.

Conservative management of acoustic neuroma.

AIM OF STUDY: To identify those patients with vestibular schwannoma (acoustic neuroma) in whom treatment becomes necessary. METHOD: Retrospective chart review. RESULT: A total of 205 patients with small tumors were followed for a mean of 40.8 months. The longest follow-up was 180 months. One hundred and ninety-seven patients had a follow-up of more than 12 months. Eight patients with a follow-up of less than 12 months were excluded from the study. In 136 patients (66.3%) the tumor did not grow. Forty-seven patients (23.9%) showed some evidence of slow growth. Eight of 197 patients (4%) had rapid growth and 6 patients (3%) had radiological evidence of tumor regression. Fifteen patients came to surgery. Five of these showed rapid growth, four developed ataxia in whom tumor growth was slow, three had ataxia without tumor growth, two patients developed brainstem compression, and one patient elected to proceed to surgery, although there were no tumor growth or symptoms. CONCLUSION: Few patients with small tumors will come to surgery in the short term. Perhaps the majority of patients with such small tumors will not need surgery. Long-term follow-up studies of 20 years or more are required to be come more confident about the natural history of these tumors. This study continues.

Promontory drilling in stapedectomy: an anatomical study.

BACKGROUND: Anatomical variants such as an overhanging facial nerve or promontory can impede access to the footplate during stapedectomy. Drilling away bone from the cochlear promontory may be required. In the case of a floating or depressed footplate, it has been recommended that a "pothole" be drilled in the inferior margin of the oval window. There is little published information on the anatomy of the promontory with respect to these maneuvers. MATERIALS AND METHODS: Twenty temporal bones were studied. A series of measurements was made to assess how much bone may safely be removed without risking damage to the underlying cochlear endosteum and, hence, spiral ligament and stria vascularis. RESULTS: The bony promontory is thickest posteriorly, and here, the endosteum has least lateral projection. The promontory becomes thinner closer to the oval window. Moving anteriorly, the bone becomes thinner and the underlying endo steum more closely follows the bony contour. The stria vascularis and spiral ligament may be less than 0.2 mm inferior to the inferior margin of the oval window posteriorly. This distance is at least 0.3 mm at the midpoint of the footplate (range, 0.3-0.5 mm). CONCLUSION: Bone may be removed inferiorly to the posterior one-third of the footplate from lateral to a line that makes an angle of 35 degrees with the superoinferior axis of the footplate. In creating a "pothole" in the case of a floating or depressed footplate, the authors recommend that it be created at the midpoint of the inferior margin of the oval window and should not exceed 0.3 mm in diameter.

Middle temporal artery flap in mastoid surgery.

OBJECTIVE: The objective of this study was to describe the anatomy of the middle temporal artery (MTA) flap and its application in mastoid surgery. STUDY DESIGN: A description of the anatomy and surgical technique. CONCLUSION: The middle temporal flap is extremely useful in lining mastoid cavities, especially those in which poor healing is anticipated. It is available in most cases and is easily harvested and inset. It is particularly useful in revision cases, if present.

Management of cystic facial neuromas: an alternative approach.

OBJECTIVE: To describe the treatment of cystic facial neuroma with drainage and marsupialization as an alternative to tumor removal and facial nerve grafting. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral hospital. PATIENTS: Two cases of cystic facial neuroma. MAIN OUTCOME MEASURES: Maintenance of facial nerve function at or better than preoperative function. RESULTS: Both cases were managed with cyst drainage. Case 1 retained House-Brackmann Grade I facial nerve function. Case 2 retained Grade II function. CONCLUSION: Cyst drainage provides a useful alternative to tumor removal and nerve sacrifice in patients with predominantly cystic facial neuromas and serviceable facial function.

Superior semicircular canal dehiscence simulating otosclerosis.

This is a report of a patient with an air-bone gap, thought 10 years ago to be a conductive hearing loss due to otosclerosis and treated with a stapedectomy. It now transpires that the patient actually had a conductive hearing gain due to superior semicircular canal dehiscence. In retrospect for as long as he could remember the patient had experienced cochlear hypersensitivity to bone-conducted sounds so that he could hear his own heart beat and joints move, as well as a tuning fork placed at his ankle. He also had vestibular hypersensitivity to air-conducted sounds with sound-induced eye movements (Tullio phenomenon), pressure-induced nystagmus and low-threshold, high-amplitude vestibular-evoked myogenic potentials. Furthermore some of his acoustic reflexes were preserved even after stapedectomy and two revisions. This case shows that if acoustic reflexes are preserved in a patient with an air-bone gap then the patient needs to be checked for sound- and pressure-induced nystagmus and needs to have vestibular-evoked myogenic potential testing. If there is sound- or pressure-induced nystagmus and if the vestibular-evoked myogenic potentials are also preserved, the problem is most likely in the floor of the middle fossa and not in the middle ear, and the patient needs a high-resolution spiral computed tomography (CT) of the temporal bones to show this.

Recurrent Rhabdoid Meningioma: Case Report.

Most meningiomas are slow-growing tumors that do not rapidly recur after subtotal removal. After subtotal resection of a meningioma a 47-year-old woman developed a large extracranial recurrence 1 year later. The recurrence was resected successfully. On histological examination the typical characteristics of a meningioma were absent. Based on immunohistological and ultrastructural studies, the tumor was classified as a grade III meningioma of the newly recognized rhabdoid subtype.These tumors behave aggressively and should be treated accordingly.