Diagnosis and management of spontaneous cerebrospinal fluid-middle ear effusion and otorrhea.

OBJECTIVES/HYPOTHESIS: Spontaneous leak of cerebrospinal fluid (CSF) into the middle ear can occur in adults without a history of temporal bone trauma or fracture, meningitis, or any obvious cause. Therefore, clues may be lacking that would alert the otolaryngologist that fluid medial to an intact eardrum, or fluid emanating from an eardrum perforation, is likely to be CSF fluid. A review of relevant medical literature reveals that herniation of the arachnoid membrane through a tegmen defect may be congenital, or CSF leak may occur when dynamic factors (i.e., brain pulsations or increases in intracranial pressure) produce a rent in the arachnoid membrane. Because tegmen defects may be multiple rather than single, identifying only one defect may not be sufficient for achieving definitive repair. Data on nine cases of spontaneous CSF leak to the ear in adult patients from four medical centers are presented and analyzed to provide collective information about a disorder that can be difficult to diagnose and manage. STUDY DESIGN: Retrospective review of nine cases of spontaneous CSF middle ear effusion/otorrhea. RESULTS: The majority of patients presented with symptoms of aural fullness and middle ear effusion. Many developed suspicious clear otorrhea only after insertion of a tympanostomy tube. Two patients had multiple defects in the tegmen and dura, and five patients had meningoencephaloceles confirmed intraoperatively. Five patients underwent combined middle cranial fossa/transmastoid repair. Materials used in repair included temporalis fascia, free muscle graft, Oxycel cotton, calvarial bone, pericranium, bone wax, and fibrin glue. CONCLUSIONS: CSF middle ear effusion/otorrhea can develop in adults without a prior history of meningitis or head trauma or any apparent proximate cause. Although presenting symptoms can be subtle, early suspicion and confirmatory imaging aid in establishing the diagnosis. Because surgical repair by way of a mastoid approach alone can be inadequate if there are multiple tegmen defects, a middle fossa approach alone, or in combination with a transmastoid approach, should be considered in most cases.

Use of the malleus handle as a landmark for localizing the round window membrane.

Localization of the round window membrane is desirable in order to allow a more direct application of medication to the inner ear. A new procedure has been developed to deliver direct, near-continuous inner ear perfusion to the round window with the Silverstein MicroWick. In this office procedure, the wick is inserted through a tympanostomy tube into the round window niche. Accurate localization of the round window is a necessary component of this procedure. In an effort to ascertain the precise location of the round window, we examined 25 cadaveric human temporal bones and measured the distance from the umbo to the round window in each sample. We found that the round window was an average of 3.44 mm (+/- 0.68) from the umbo and was situated at an average angle of 113.2 degrees (+/- 9.8) from the long process of the malleus. Our simple and reliable determination of the relationship between the malleus handle and the round window niche allows for the accurate placement of the Silverstein MicroWick and other devices.

Pediatric laser-assisted tympanostomy.

OBJECTIVE: To evaluate effectiveness of laser-assisted tympanostomy in treatment of pediatric patients with chronic otitis media with effusion. STUDY DESIGN: Retrospective review of 23 pediatric patients who received office laser-assisted tympanostomy. METHODS: A CO2 laser attached to an operating microscope with a microscope laser adaptor device or the handheld Oto-LAM (Needham, MA) was used to perform all of the tympanostomies. The average diameter of tympanostomy was 2 mm; on average, 13.6 W was applied for 0.13 seconds. RESULTS: Laser-assisted tympanostomy was performed on 37 pediatric ears (patient age range, 2-16 y) for the diagnosis of chronic otitis media with effusion. Average follow-up time was 4.7 weeks. At the time of the follow-up examination, 46% of the ears had no evidence of fluid and required no further intervention. Forty-nine percent of the ears required placement of pressure equalization tubes. The average SRT improved from 30.8 dB preoperatively to 21.03 dB postoperatively. CONCLUSIONS: Laser-assisted tympanostomy appears to be an effective treatment for chronic otitis media with effusion in pediatric patients.

Natural history of acoustic neuromas.

OBJECTIVES/HYPOTHESIS: 1) Develop a computerized technique to accurately compare acoustic neuroma size on routine computed tomography and magnetic resonance imaging (MRI) scans; 2) use this technique to determine the growth pattern in a large series of patients with acoustic neuroma who were conservatively managed; 3) describe the natural history of patients with acoustic neuromas who did not receive surgical intervention and those who underwent subtotal resection; 4) correlate the size and growth rate of acoustic neuromas to clinical presentation and auditory and vestibular testing; and 5) recommend guidelines for the management of patients with acoustic neuromas. STUDY DESIGN: A retrospective study from 1974 to 1999 of patients with unilateral acoustic neuromas who had conservative treatment by serial imaging studies (80 patients) or subtotal resection (49 patients). METHODS: All patient charts were evaluated for presenting symptoms, reasons for the type of management given, and clinical outcome. Charts were also reviewed with respect to serial audiological assessment, electronystagmography, and brainstem auditory evoked response. Imaging studies were analyzed using a computer technique so that serial studies could be compared to determine growth rates. RESULTS: Rigorous computer analysis of tumor size and growth rate was statistically the same as the radiologist's description of the tumor size and growth rate. Of 70 patients who were older than 65 years of age old at the time their tumor was discovered, 4 (5.7%) required intervention and 18 (26%) were dead of unrelated causes. These patients had a mean follow-up of 4.8 years (range, 0.01-17.2 y). Overall, growth rate for nonsurgical patients was 0.91 mm per year. Nonsurgical tumors did not grow or regressed in 42%. Overall postoperative growth rate for surgical subtotal resection patients was 0.35 mm per year. Surgical tumors did not grow or regressed after subtotal resection of acoustic neuroma in 68.5% of patients. Three patients (6.1%) required revision surgery because of tumor growth or the development of symptoms. Neither auditory nor vestibular testing was a reliable measure for determining tumor growth. CONCLUSION: Measurement of the maximal tumor diameter on MRI scans is a reliable method for following acoustic neuroma growth. There is no need to perform a rigorous analysis of tumor size to determine whether the tumor is growing significantly. The vast majority of patients older than 65 years with acoustic neuromas do not require intervention. The indications for intervention should be based on a combination of rapid tumor growth with the development of symptoms.

Intraoperative facial nerve monitoring: a comparison between electromyography and mechanical-pressure monitoring techniques.

OBJECTIVES: To examine the hypothesis that for intraoperative facial nerve monitoring, an EMG monitor is more sensitive than a mechanical-pressure monitor. To compare the threshold sensitivity of the two facial nerve monitoring methods-mechanical-pressure versus EMG--by using them simultaneously during surgery. To assess and compare their true- and false-positive responses in otologic and neurotologic procedures. SETTING: A tertiary referral private otology/neurotology practice. STUDY DESIGN: Prospective case-controlled study. PATIENTS AND METHODS: The facial nerve of 46 consecutive patients undergoing various otologic and neurotologic procedures was stimulated intraoperatively using a pulsed constant-current. Facial responses were monitored using the Silverstein WR-S8 Monitor/Stimulator and the Brackmann EMG System simultaneously. The threshold (i.e., minimal) current level required to elicit a response from each monitor was recorded. Monitor responses to facial nerve manipulation (including false-positive responses) were assessed by continuous recording of all responses, using the Wiegand Monitoring System, and noting the causative event for each response. RESULTS: The EMG monitor responded to lower current threshold (p < 0.001) in every surgical procedure and for every nerve segment studied. However, the average threshold difference was <0.05 mAmps and in clinical practice, when using above threshold stimulation, becomes negligible. In posterior fossa surgery, the EMG monitor showed higher sensitivity by responding earlier to various manipulations of the bare facial nerve. The EMG had more false-positive responses than the mechanical-pressure monitor. CONCLUSIONS: In otologic surgery, if monitoring is required, the mechanical-pressure monitor is used. In neurotologic surgery, both monitors are used simultaneously.

Vestibular surgery for Ménière's disease in the elderly: a review of techniques and indications.

There are several safe and effective surgical options for the treatment of vertigo associated with Ménière's disease in the elderly patient. The choice of procedure depends on the patient's hearing status and overall health. Since 1987, combined retrolabyrinthine-retrosigmoid posterior fossa vestibular neurectomy was performed on 29 older patients who were in good physiologic health and whose hearing was better than 80 dB pure-tone average and 20% speech discrimination. Patients whose hearing is worse are offered transmastoid labyrinthectomy or transmeatal cochleovestibular neurectomy, barring contraindications. When extensive surgery is medically contraindicated and hearing is not a significant concern, cochleosacculotomy is preferred; this procedure has been performed with minimal morbidity on patients as old as 85. Finally, over the past several years, patients have been treated with transtympanic placement of gentamicin. Early results with this office-based local procedure demonstrate a high care rate, but also a high incidence of sensorineural hearing loss.

Direct round window membrane application of gentamicin in the treatment of Meniere's disease.

OBJECTIVE: To evaluate the effectiveness of the round window membrane (RWM) Gelfoam gentamicin technique in patients with Meniere's disease who were unresponsive to medical management or in whom surgical therapy failed. STUDY DESIGN: Protocol 1, single intratympanic gentamicin infusion; protocol 2 (the best method), 2 infusions, 5 days apart with reevaluation at 1 month; and protocol 3, multiple infusions 1 to 4 weeks apart. PATIENTS: In total, 32 patients (19 male, 13 female) were enrolled in the study. The mean age was 65 years (range 34 to 94 years). Seven of these patients were surgical salvage cases. INTERVENTIONS: Laser-assisted otoendoscopy with a 1.7-mm otoendoscope (Smith-Nephew Richards, Memphis, TN) was performed first. If the RWM was obscured by mucosa or adhesions, these were cleared before placing a 2 x 3 mm piece of dry Gelfoam against the RWM. Buffered gentamicin (26.7 mg/mL) was then injected into the middle ear (0.2 to 0.3 mL). RESULTS: Overall, vertigo was controlled in 75% of the patients after the completion of the treatment, with subtotal vestibular ablation in two thirds of patients. Hearing was preserved in 90% of the patients (within 15 dB pure-tone average or 15% speech discrimination score), tinnitus improved in 48%, and aural pressure improved in 62.5%.

A reevaluation of the 512-Hz Rinne tuning fork test as a patient selection criterion for laser stapedotomy.

OBJECTIVE: This study aimed to challenge the classical hypothesis that a negative preoperative 512-Hz Rinne tuning fork test (bone conduction greater than air conduction) is a necessary condition to allow consistent objective and subjective hearing improvement with surgery for otosclerosis. STUDY DESIGN: The study design was retrospective (chart review and questionnaire). SETTING: The study was conducted at a Florida Ear and Sinus Center at Sarasota, Florida, a tertiary otology-neurotology referral center. PATIENTS: Patients who underwent primary laser stapedotomy with equivocal (air=bone) preoperative 512-Hz Rinne test results participated. INTERVENTION: KTP laser stapedotomy was performed. MAIN OUTCOME MEASURES: Audiologic measurements of air-bone gap closure and patient assessment of hearing improvement and satisfaction were conducted. RESULTS: The air-bone gap was closed to within 10 dB in all cases. There were no complications. Eighteen patients were questioned about their results. Hearing improvement was subjectively described as "excellent" or "good" by 17 (94%), and 16 (89%) thought the surgery was "absolutely" worthwhile. CONCLUSIONS: The preoperative 512-Hz Rinne test results need not be negative to achieve significant air-bone gap closure and subjective appreciation of improved hearing.

Preservation of the stapedius tendon in laser stapes surgery.

OBJECTIVES/HYPOTHESIS: The stapedius tendon is routinely transected during stapes surgery. The objective of this study was to evaluate the technique of stapedial tendon preservation during stapes surgery and to compare results of these cases with cases where the stapedial tendon was not preserved. STUDY DESIGN: Retrospective study. METHODS: Four groups of patients were evaluated. Two groups had undergone stapes surgery with preservation of the stapedial tendon. One of these groups underwent a laser stapedotomy minus prosthesis (laser STAMP) procedure, while the other group had a prosthesis inserted. The other two groups had undergone laser stapedotomy with one of two different prostheses being used. Audiometric data were obtained and reviewed both preoperatively and at approximately 6 weeks postoperatively. RESULTS: All groups had overall successful results demonstrating that stapedial tendon preservation is technically possible and does not compromise outcomes. CONCLUSIONS: Based on the results, it is recommended that the stapedius tendon be preserved whenever possible during laser stapes surgery. Reasons justifying its preservation are discussed.

Effect of melatonin on tinnitus.

OBJECTIVE: Evaluate melatonin as a treatment for subjective tinnitus. STUDY DESIGN: Randomized, prospective, double-blind, placebo-controlled crossover trial. Patients were given 3.0 mg melatonin, which was taken nightly for 30 days followed or preceded by a placebo nightly for 30 days, with a 7-day washout period between medications. SETTING: Outpatient, private, neurotology practice. PATIENTS: Thirty patients with subjective tinnitus. MAIN OUTCOME MEASURES: Tinnitus matching, Tinnitus Handicap Inventory (THI), patient questionnaire and interview. RESULTS: The average pretreatment THI score was 33.91 as compared with 26.43 after the placebo and 26.09 after melatonin. The difference in the THI scores between melatonin and placebo treatment were not statistically significant. The average pretreatment THI score for patients who reported overall improvement with melatonin was statistically higher (P = 0.02) than the average pretreatment THI score for patients who reported no improvement with melatonin. Among subjects reporting difficulty sleeping attributable to their tinnitus, 46.7% reported an overall improvement after melatonin compared with 20.0% for placebo (P = 0.04). There was also a statistically significant difference in improvement with melatonin for those patients with bilateral tinnitus compared with those with unilateral tinnitus (P = 0.02). CONCLUSION: Melatonin has been shown to be useful in the treatment of subjective tinnitus. Patients with high THI scores and/or difficulty sleeping are most likely to benefit from treatment with melatonin. In light of its minimal side effects, melatonin should be a part of the physician's armamentarium in the treatment of tinnitus.

Inner ear perfusion and the role of round window patency.

OBJECTIVE: The goal of this investigation was to evaluate the degree of round window membrane obstruction in the native state. The implications for the perfusion of the inner ear via the intratympanic instillation of medications are addressed. STUDY DESIGN: This was a retrospective chart review and a prospective intraoperative observation in the setting of an outpatient office. PATIENTS: The study population was composed of 41 patients who were undergoing middle ear endoscopy before perfusion of the inner ear with medication for the treatment of Meniere's disease, sudden sensorineural hearing loss, or tinnitus. INTERVENTION: Office-based laser-assisted tympanostomy and middle ear endoscopy was carried out in each case. Lysis of adhesions overlying the round window membrane was undertaken when the underlying round window membrane could not be visualized. MAIN OUTCOME MEASURES: Evaluation of the round window niche with regard to accessibility of the round window membrane was recorded for each patient studied. RESULTS: Of the 41 cases examined, 29 of the round windows were judged to be unobstructed, 7 were obstructed partially, and 5 were obstructed completely. CONCLUSION: A significant rate of round window obstruction exists among patients who have no history of manipulation to this area. Although, intuitively, we would expect prior middle ear surgery to increase the likelihood of obstruction, this is not uniformly the outcome. If intratympanic instillation of a medication is contemplated for the treatment of an inner ear disorder, considerations for the evaluation of the round window should be made to enhance adequate diffusion into the perilymph.

Laser-assisted tympanostomy.

Laser-assisted tympanostomy (LAT) was performed in 70 ears to ventilate the middle ear space without using a pressure-equalizing tube. Using a CO2 laser attached to an operating microscope with a Microslad (microscope laser adaptor device), tympanostomies of 1.0 to 3.0 mm (average, 1.6 mm) in diameter were created and remained patent for an average of 3.14 weeks. Patency time was directly related to the size of the opening. Nearly all (97.9%) of the tympanostomies healed with no noticeable scarring and no persistent perforations. Seventy-eight percent of patients at the Florida Ear & Sinus Center (FESC, Sarasota, Fla.) and 84% of patients at the Head & Neck Surgery Group (New York) showed no evidence of recurrent effusion after a minimum follow-up of 3 months. LAT appears to be a safe, cost-effective procedure which can easily be performed in an office setting when bloodless opening in the tympanic membrane is needed for either treatment or diagnosis using endoscopes.

Intratympanic steroid treatment of inner ear disease and tinnitus (preliminary report).

Intratympanic instillation of Depo-Medrol (80 mg/cc), dexamethasone ophthalmic solution (1 mg/cc), or dexamethasone intravenous (4 mg/cc) solution produces improvement of cochlear function in certain patients with Meniere's disease, autoimmune inner ear disease and sudden sensorineural deafness. Tinnitus improved in 47%, most often in patients with Meniere's disease (9 of 15; 60%). The SRT improvement of greater than 10 dB or SD greater than 15% was documented in 41% (average improvement in SRT: 15 dB; SD: 24%). Patients with tinnitus and bilateral sensorineural hearing loss (i.e., presbycusis) did not benefit from the treatment. Prior to treatment with intratympanic medication, laser assisted tympanostomy with middle ear exploration, using otoendoscopy to determine the status of the round window niche and remove mucosal folds, helps in making the round window membrane accessible to local application of drops. Placing Gelfoam into the round window niche under direct vision, and using a Venturi Bobbin tube in the tympanic membrane, appears to be a satisfactory method for delivering medication to the inner ear fluids. The medication can be injected by the physician through the tube into the middle ear, or the patient can perform self-treatment at home, placing medication in the external auditory canal. A double-blind, cross-over study in patients with Meniere's disease is now in progress with Institutional Review Board (IRB) approval, which will be reported at a later date. This preliminary study has shown that intratympanic steroids may affect the symptoms of hearing loss and tinnitus in patients with various inner ear problems. Patients with Meniere's disease appear to respond in the highest percentage of cases. Hopefully, additional research will suggest the appropriate drugs which can be used to treat inner ear disease. Direct application of the drug to the round window membrane may increase the concentration in the inner ear fluids, thus avoiding the systemic effects.

Endoscopic otologic surgery.

In this article, various otologic and neurotologic procedures, including middle ear exploration, chronic ear disease surgery, second-look mastoidectomy, acoustic neuroma surgery, and vestibular neurectomy, are reviewed for the usefulness of minimally invasive endoscopic techniques.

Hearing results after posterior fossa vestibular neurectomy.

The effect of posterior fossa vestibular neurectomy on postoperative hearing levels of 172 patients was studied at 1 week, 1 month, 1 year, and 18 to 24 months. According to the 1985 American Academy of Otolaryngology-Head and Neck Surgery guidelines for reporting treatment outcome, 66% of patients had improved or unchanged hearing at 18 to 24 months. One-week postoperative hearing was poorer than at 1 month or later follow-up. Permanent profound hearing loss occurred in 4.7% of patients. In patients who had worse than 80 dB pure-tone average and 20% speech discrimination score hearing loss before surgery, 68% improved above this hearing level, and 16% improved to better than 50 dB pure-tone average and 50% speech discrimination after surgery. This suggests that it may be worthwhile to preserve the cochlear nerve in certain patients who may otherwise be candidates for labyrinthectomy. These hearing results are comparable with other treatment modalities including endolymphatic sac surgery.

Use of endoscopes for chronic ear surgery in children.

OBJECTIVE: To determine whether an endoscopic second-look examination of the mastoid and middle ear could replace an open second-look mastoidectomy. DESIGN: Patients were examined endoscopically. The findings were compared with a standard open mastoidectomy procedure during the same operation. The mastoid can be inspected through a small postauricular incision and the middle ear can be inspected through a myringotomy incision or tympanomeatal flap. PATIENTS: Ten patients aged 6 to 16 years. RESULTS: Endoscopic findings correlated exactly with open mastoidectomy findings in all cases. CONCLUSION: In light of this study an open second-look mastoidectomy may be avoided if minimal or no recurrent cholesteatoma is found during the endoscopic exploration. The use of the ridged endoscope has added another dimension to the standard microsurgical techniques used in pediatric otology. The indications, techniques, and findings of otoendoscopy in the management of chronic otitis media in children will be presented.

Lightning injury of the tympanic membrane.

Lightning injury to the ear is known, but specific reports are lacking. Four patients with tympanic membrane perforations who were managed surgically are reported. Their presentations, evaluations, intraoperative findings, and outcomes are discussed as they relate to the proposed pathogenic mechanisms. The authors' standard wide exposure tympanoplasty approach with two layer tympanic membrane repair is described. The added steps in performing this procedure may be necessary to ensure a good result in this unique group of patients.

The jugular dural fold-a helpful skull base landmark to the cranial nerves.

During a retrosigmoid (or combined retrolabyrinthine-retrosigmoid) approach to the posterior fossa for vestibular neurectomy or removal of small acoustic neuromas, a white dural fold is a consistent landmark to cranial nerves VII through XII. This fold of dura appears as a white linear structure extending from the foramen magnum across the sigmoid sinus, attaching to the posterior aspect of the temporal bone, anterior to the vestibular aqueduct. The name "jugular dural fold" is suggested for this landmark. The jugular dural fold overlies the junction of the sigmoid sinus and the jugular foramen. As measured in formalin-fixed cadaver heads, the overall length of the jugular dural fold is 20.8 mm (+/- 2.9 mm). The cochleovestibular nerve lies 9.9 mm (+/- 1.5 mm) anterior to the superior aspect of the jugular dural fold, the glossopharyngeal nerve lies 9.5 mm (+/- 1.6 mm) anterior to the midpoint of the jugular dural fold, and the operculum of the vestibular aqueduct lies 6.6 mm (+/- 0.7 mm) posterior to the jugular dural fold. Intraoperative measurements in patients undergoing combined retrolabyrinthine-retrosigmoid vestibular neurectomy show an overall length of the jugular dural fold of 16.3 mm (+/- 1.9 mm). The cochleovestibular nerve lies 8.6 mm (+/- 1.3 mm) anterior to the superior aspect of the jugular dural fold, the glossopharyngeal nerve lies 8.6 mm (+/- 1.3 mm) anterior to the midpoint of the jugular dural fold, and the operculum lies 7.5 mm (+/- 0.8 mm) posterior to the jugular dural fold. The jugular dural fold can be used as a reliable landmark for rapidly locating cranial nerves in the posterior fossa.

Superficial siderosis of the central nervous system: an underdiagnosed cause of sensorineural hearing loss and ataxia.

Superficial siderosis of the central nervous system (CNS) is a rare but ultimately fatal disorder characterized by progressive hearing loss, ataxia, and dementia. Symptoms are caused by the deposition of hemosiderin in the CNS as a result of recurrent or persistent extravasation of blood into the cerebrospinal fluid. Sites most commonly involved include the cerebellum, brain stem, and eighth cranial nerve. In the past, diagnosis was most often made at autopsy, and this may account for the lack of reported cases in the otolaryngologic literature and the presumed rarity of the disorder. Now, diagnosis is confirmed by characteristic magnetic resonance imaging findings and treatment is targeted toward the source of bleeding. The diagnosis of superficial CNS siderosis should be entertained in all patients presenting with sensorineural hearing loss and ataxia.