Debara L. Tucci

Clinical Practice Guideline: Sudden Hearing Loss

Objective. Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with SHL. The guideline primarily focuses on sudden sensorineural hearing loss (SSNHL) in adult patients (aged 18 and older). Prompt recognition and management of SSNHL may improve hearing recovery and patient quality of life (QOL). Sudden sensorineural hearing loss affects 5 to 20 per 100,000 population, with about 4000 new cases per year in the United States. This guideline is intended for all clinicians who diagnose or manage adult patients who present with SHL. Purpose. The purpose of this guideline is to provide clinicians with evidence-based recommendations in evaluating patients with SHL, with particular emphasis on managing SSNHL. The panel recognized that patients enter the health care system with SHL as a nonspecific, primary complaint. Therefore, the initial recommendations of the guideline deal with efficiently distinguishing SSNHL from other causes of SHL at the time of presentation. By focusing on opportunities for quality improvement, the guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients. Results. The panel made strong recommendations that clinicians should (1) distinguish sensorineural hearing loss from conductive hearing loss in a patient presenting with SHL; (2) educate patients with idiopathic sudden sensorineural hearing loss (ISSNHL) about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy; and (3) counsel patients with incomplete recovery of hearing about the possible benefits of amplification and hearing-assistive technology and other supportive measures. The panel made recommendations that clinicians should (1) assess patients with presumptive SSNHL for bilateral SHL, recurrent episodes of SHL, or focal neurologic findings; (2) diagnose presumptive ISSNHL if audiometry confirms a 30-dB hearing loss at 3 consecutive frequencies and an underlying condition cannot be identified by history and physical examination; (3) evaluate patients with ISSNHL for retrocochlear pathology by obtaining magnetic resonance imaging, auditory brainstem response, or audiometric follow-up; (4) offer intratympanic steroid perfusion when patients have incomplete recovery from ISSNHL after failure of initial management; and (5) obtain follow-up audiometric evaluation within 6 months of diagnosis for patients with ISSNHL. The panel offered as options that clinicians may offer (1) corticosteroids as initial therapy to patients with ISSNHL and (2) hyperbaric oxygen therapy within 3 months of diagnosis of ISSNHL. The panel made a recommendation against clinicians routinely prescribing antivirals, thrombolytics, vasodilators, vasoactive substances, or antioxidants to patients with ISSNHL. The panel made strong recommendations against clinicians (1) ordering computerized tomography of the head/brain in the initial evaluation of a patient with presumptive SSNHL and (2) obtaining routine laboratory tests in patients with ISSNHL.

Physiologic Status of Regenerated Hair Cells in the Avian Inner Ear following Aminoglycoside Ototoxicity

Regeneration of avian inner ear hair cells has been demonstrated after administration of aminoglycoside and after acoustic trauma. However, no published study to date has documented functional recovery of these regenerated sensory receptor cells. Newborn chicks were treated with gentamicin sulfate (50 mg/kg/day) for a total of either 5 (n = 10) or 10 (n = 76) days. Evoked potential thresholds were obtained one day after the 5-day treatment, or at intervals between one day and 20 weeks after the 10-day treatment course, and compared to thresholds of age-matched control animals. A significant hearing loss, predominantly in the high frequencies, was present after as few as 5 days of drug administration. The magnitude of hearing loss continued to increase, especially at lower frequencies, as survival increased from 1 day to 5 weeks after gentamicin treatment. Sixteen-to-20 weeks after treatment, partial recovery of thresholds was evident. These findings demonstrate that functional recovery does occur in the avian inner ear following aminoglycoside administration. Recovery occurs at all frequencies, but predominantly at low and middle frequencies, leaving significant residual high-frequency threshold elevation. Recovery lags 14 to 18 weeks behind anatomic evidence of hair cell regeneration, which was demonstrated in one study by 2 weeks after comparable administration of gentamicin.

Treatment of sudden sensorineural hearing loss with systemic steroids and valacyclovir.

Objective To determine if the addition of an antiviral medication to systemic steroids improves recovery in the treatment of idiopathic sudden sensorineural hearing loss. Study Design Randomized, double-blind, placebo-controlled prospective multicenter clinical trial. Setting The study was administrated from a tertiary care center and clinical research institute; patients were enrolled by otolaryngologists in academic and private practice outpatient settings. Patients Inclusion criteria included 1) loss of at least 30 dB in 3 contiguous frequencies over <3 days in patients with previous audiometry, 2) marked loss of hearing in patients with prior subjectively normal hearing and no previous audiometry, with contralateral hearing taken as baseline, and 3) patients seen within 10 days of onset of hearing loss. Pretreatment evaluation included audiometry and complete blood cell count, complete blood chemistry, and fluorescent treponemal antibody absorption test. Auditory brainstem-evoked response or magnetic resonance imaging was recommended. Intervention Patients received prednisone (80 mg/d for 4 d, then tapered over 8 d) with placebo or prednisone with valacyclovir (1 g, 3 times a day for 10 days). Main Outcome Measure 1) Audiometric assessment at presentation, Week 2, and Week 6; 2) Hearing Screening Inventory questionnaire twice weekly for 6 weeks; and 3) acute Short Form-12 questionnaire at presentation and Week 2. Results Of 105 subjects enrolled in the study, 84 subjects were evaluable. There were no significant differences between placebo and valacyclovir treatment groups in terms of hearing recovery or symptom recovery on the basis of the Hearing Screening Inventory or Short Form-12 questionnaires. No adverse events were related to the use of valacyclovir. Conclusion Within the paradigm used in the current study, an antiviral medication did not provide more benefit than steroid alone in the treatment of idiopathic sudden sensorineural hearing loss.

Treatment of an Iatrogenic Petrous Carotid Artery Pseudoaneurysm with a Symbiot Covered Stent: Technical Case Report

OBJECTIVE AND IMPORTANCE Surgery involving the middle ear or the temporal bone may cause an injury to the petrous carotid artery resulting in a pseudoaneurysm. Conventional treatment of such pseudoaneurysms has ranged from carotid occlusion to conservative management. The use of a balloon-expandable stent and/or Guglielmi detachable coils may be effective in a partially healed pseudoaneurysm. This report details the case of an acute petrous carotid pseudoaneurysm after a myringotomy procedure that was effectively treated with an expanded polytetrafluoroethylene-covered stent. CLINICAL PRESENTATION During a right myringotomy procedure, pulsatile blood was encountered in a 42-year-old woman with a history of repeated ear infections and bilateral middle ear ventilation tube placement. The blood was adequately tamponaded with gauze packing. Computed tomography of the temporal bone demonstrated a dehiscent carotid artery, and cerebral angiography revealed a 6-mm right petrous carotid pseudoaneurysm. INTERVENTION/TECHNIQUE An 8-French guide catheter was positioned via a transfemoral approach into the cervical right internal carotid artery, and the patient was systemically heparinized. A 4- × 31-mm Symbiot covered stent (Boston Scientific/Scimed, Maple Grove, MN) was passed over a Choice PT exchange wire (Boston Scientific/Scimed) to cover the neck of the pseudoaneurysm, obliterating the pseudoaneurysm. The patient was given aspirin and clopidogrel after stenting, and ear exploration was possible later the same day. Follow-up computed tomographic angiography performed 6 weeks later verified patency of the stent. CONCLUSION The use of an expanded polytetrafluoroethylene-covered stent may effectively treat intracranial internal carotid artery pseudoaneurysms in an acute setting. This treatment allows preservation of the parent artery and immediate treatment by reconstruction of the incompetent arterial wall to prevent potentially life-threatening hemorrhagic complications.

Anatomical correlates of functional recovery in the avian inner ear following aminoglycoside ototoxicity

Tucci and Rubel have demonstrated functional recovery of the chick cochlea following aminoglycoside ototoxicity. The cochleae of these same animals were examined by scanning electron microscopy (SEM) in order to further understand this recovery process.

Conductive Hearing Loss Results in a Decrease in Central Auditory System Activity in the Young Gerbil

Objectives/Hypothesis: The impact of childhood conductive HL (CHL) on development of auditory function has long been debated. The present study was conducted to define and compare the consequences of CHL and cochlear ablation (CA) in young and adult animals, using 2‐deoxyglucose (2‐DG) uptake as a measure of metabolic activity. It was hypothesized that, for both ages, CHL would result in a decrease in activity in the major ascending central auditory system pathway of the manipulated ear, but that this decrease would be significantly less than that observed with CA.

Changes in Spontaneous Activity and Cns Morphology Associated with Conductive and Sensorineural Hearing Loss in Chickens

The effects of a conductive or mixed (conductive and sensorineural) hearing loss on anatomical and physiological properties of the chicken auditory system were examined. Animals used in the anatomical studies underwent either a columella (ossicle) removal, which produced a moderate conductive hearing loss, or an oval window puncture, which produced a severe mixed hearing loss, at 4 days posthatch. In a companion study, multiunit spike counts were obtained from 3-week-old chickens before, during, and after consecutive tympanic membrane puncture, columella removal, and oval window puncture. Tympanic membrane puncture and columella removal (conductive hearing loss) are not associated with either cell area changes in the nucleus magnocellularis or changes in spontaneous neuronal activity. Conversely, an oval window puncture (sensorineural damage) is associated with a cell area reduction of 20%, as well as a marked decline in activity within auditory nuclei.

Treatment of tinnitus with gabapentin: a pilot study.

Objective: To evaluate the effectiveness of gabapentin (Neurontin®) improve the disease-specific quality of life in patients with moderate tinnitus. Study Design: Randomized, double blind, placebo-controlled clinical trial. Setting: Single-center academic outpatient otolaryngology practice. Intervention: Gabapentin 1800 mg daily versus placebo. Main Outcome Measures: The study design is a randomized, double blind placebo controlled single site trial conducted in an academic medical center. Inclusion criteria included patients between ages 18 and 70 with a complaint of nonpulsatile, subjective tinnitus, bilateral or unilateral, greater than 3 months in duration. The primary outcome measure is the Tinnitus Handicap Inventory; secondary measures include the Profile of Mood States (POMS) rating scale, subjective tinnitus severity. The null hypothesis addressed in this study is that the drug would not result in significant alleviation of the symptom of tinnitus. Results: Seventy-six patients completed the trial; of these 52 received the drug. No significant differences were found between the two groups after 5 weeks of treatment with gabapentin. Conclusion: There is insufficient evidence to support the effectiveness of gabapentin in the treatment of tinnitus.

Amphetamine effects on long term potentiation in dentate granule cells

Long term potentiation (LTP) has received considerable attention as a neurophysiological analog of memory. Amphetamine, as well as several other catecholamine agonists, can enhance behaviorally-assessed memory storage in a variety of training situations. The present experiments tested the effects of amphetamine on LTP produced by high frequency stimulation of the perforant path in rats. The results indicate that amphetamine can enhance the development of LTP under some but not all testing procedures. Studies of the neurobiological bases by which central and peripheral catecholamines modulate memory storage may be augmented by examinations of catecholamine effects on a specific form of long-lasting change in brain function. Similarly, the ability to manipulate LTP may prove to be an important aid in examinations of neurobiological correlates of this phenomenon.

A randomized, double-blind, placebo-controlled clinical study to assess safety and clinical activity of OTO-104 given as a single intratympanic injection in patients with unilateral Ménière's disease.

Objective To evaluate the safety, tolerability, and clinical activity of a single intratympanic injection of OTO-104, sustained-release dexamethasone formulation, in patients with unilateral Ménière’s disease. Study Design Prospective, double-blind, randomized, placebo-controlled, dose-escalation study of 16 weeks’ (4–wk lead-in before dosing; 12–wk follow-up after dosing) duration for each patient. Setting Fifteen centers (physician offices and academic or tertiary referral centers). Patients Forty-four patients aged 22 to 75 years. Intervention Single intratympanic injection of OTO-104 (3 or 12 mg) or placebo. Main Outcome Measures Safety and tolerability were assessed via adverse event reports, otoscopy, audiometry, and tympanometry. Clinical activity was assessed primarily as changes in vertigo frequency. Results OTO-104 was well tolerated, with no impact on hearing function. Plasma levels were observed in a few patients and were barely quantifiable. The most frequently reported adverse event considered related to investigational product was tympanic membrane perforation; no clinical sequelae were associated with these perforations and all were graded mild or moderate. At Month 3, the observed mean ± standard deviation (SD) change from baseline in vertigo frequency was −0.124 ± 0.153, −0.147 ± 0.166, and −0.211 ± 0.153 for the placebo, 3-mg OTO-104, and 12-mg OTO-104 groups, respectively; corresponding to 42%, 56% and 73% reductions in vertigo frequency, respectively. Similar results were observed for tinnitus, measured by the Tinnitus Handicap Inventory (THI–25). Conclusion OTO-104 was safe and well tolerated. Although the sample size was small, the data suggest 12 mg of OTO-104 was associated with a clinically meaningful reduction in vertigo frequency compared to placebo 3 months after treatment.