Ronald A. Hoffman

Complications of Cochlear Implant Surgery in Adults and Children

Surgery for cochlear prosthesis insertion exposes the patient to several potential risks. We review the surgical complication experience with cochlear implants in the United States. There have been no deaths attributable to these devices, few serious major complications, and relatively few minor complications. Major complications usually have to do with surgical technique and include flap necrosis, improper electrode placement, and rare facial nerve problems. Minor complications include dehiscence of incisions, infection, facial nerve stimulation, dizziness, and pedestal problems with the Ineraid device. Complications were less frequent in children than adults and were more likely to occur in the younger children than those above the age of 7 years. Complications were still fewer in groups of patients operated on within tightly controlled protocols. There was no increased incidence of otitis media in children who received the Nucleus Mini-22 device, and no reported sequelae from such otitis when it occurred.

Cerebrospinal fluid leak following acoustic neuroma removal

Cerebrospinal fluid (CSF) leak has been a constant and unresolved complication of acoustic tumor surgery. This study retrospectively reviews 381 primary acoustic tumor surgeries performed by a single, senior, neurotologist and neurosurgeon team from 1979 through 1991. There were 68 cerebrospinal fluid leaks in 66 patients (66/381; 17%). There was no significant difference in the incidence of CSF leak between the translabyrinthine group (21%) and the retrosigmoid transmeatal group (16%). Translabyrinthine leaks were evenly divided between rhinorrhea and the postauricular wound while retrosigmoid transmeatal leaks were predominantly rhinorrhea. Eleven of 14 translabyrinthine wound leaks responded to pressure dressing and suture. The remaining 3 ceased with continuous lumbar cerebrospinal fluid drainage. Ten of 14 cases of translabyrinthine rhinorrhea responded to continuous lumbar cerebrospinal fluid drainage, and those in whom it failed were cured with revision of the mastoidectomy/labyrinthectomy cavity. Twenty‐one of 28 cases of retrosigmoid transmeatal rhinorrhea responded to continuous lumbar cerebrospinal fluid drainage, and those in whom it failed were cured with extracranial, transmastoid revision. The incidence of cerebrospinal fluid leak was not influenced by age, sex, size of tumor, postoperative hydrocephalus, or the intraoperative use of autologous fibrin glue. Meningitis was an unusual complication, occurring in 3% of all patients.

Cholesterol cysts of the temporal bone : diagnosis and treatment

Cholesterol cyst (or granuloma) of the temporal bone, a recognized clinical entity distinct from cholesteatoma, is more common than previously thought. Apparently it is caused by obstruction of previously pneumatized temporal bone air cells. Surgical cure is achieved by drainage and reestablishment of normal pneumatization. This paper reviews 14 cholesterol cysts of the temporal bone, emphasizing the importance of preoperative imaging and surgical approach. Use of magnetic resonance imaging differentiates cholesterol cysts from cholesteatoma or other neoplasms. Computed tomography delineates the location of the lesion and defines temporal bone anatomy essential to surgical approach. The two studies together allow the surgeon to properly plan drainage, as in the case of a cholesterol cyst, versus excision or exteriorization, as in the case of cholesteatoma. The infralabyrinthine approach to a petrous apex cholesterol cyst is the procedure of choice when hearing preservation is desired.

Surgical Complications of Multichannel Cochlear Implants in North America

By paying careful attention to the details of surgical technique, many of the complications which have occurred to date may be avoided. Some, such as late electrode and receiver/stimulator migration, device failures, and late flap necrosis due to excessive magnetic forces cannot be avoided by the surgeon, but may be prevented by further advances in implant designs. Although the incidence of life-threatening complications is minimal, and that of major complications is acceptable, every effort should be made by the surgeon, audiologist and manufacturer to further diminish these problems.

IgG4-related disease presenting as recurrent mastoiditis

IgG4-related disease (IgG4-RD) is a recently recognized disorder characterized by an overabundance of IgG4-positive plasma cells in affected tissues and, frequently, elevated serum IgG4 levels. First recognized in the context of autoimmune pancreatitisi, IgG4-RD presents as either a localized area of involvement within a single organ or as a multicentric disease, affecting several organs. Those organs include the pancreas, gallbladder, salivary glands, retroperitoneum, kidneys, lungs, prostate, ocular adnexaii, maxillary sinus, ethmoid sinusiii, lacrimal glands, breast, liver, large blood vessels, mediastinum, lymph nodesiv, pituitaryv, esophagusvi, and dura matervii. The histopathology of IgG4-RD involves a lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis. The disease process generally destroys the normal tissue architecture and replaces it with fibrotic tissue, creating a variety of histologic patterns. The appearance can be pseudolymphomatous (characterized by a dense infiltrate of small lymphocytes), sclerosing (characterized by fibrosis with some areas of lymphocyte aggregates), or mixed (characterized by fibrosis, plasma cells, and lymphocytic infiltrates)viii. IgG4-RD lesions can progress by infiltrating the surrounding tissues or by expanding as a space-occupying mass. The lesions are often exquisitely sensitive to glucocorticoids, but long-term, prospective therapeutic trials are lacking. We hereby describe a patient with IgG4-RD manifesting as recurrent inflammatory disease of the middle ear and mastoid, complicated by bone erosion.

William House Cochlear Implant Study Group: Position Statement on Bilateral Cochlear Implantation

During the past three decades, unilateral cochlear implantation (CI) has been established as an accepted medical treatment for selected individuals with advanced degrees of sensorineural hearing loss. More recently, a growing number of patients have received bilateral CI, and a developing body of literature has demonstrated a significant additional benefit from 2 implants. In turn, this has generated increasing public interest in bilateral CI. Naturally, third-party payers and governmental agencies have sought evidence to justify bilateral CI. In response, the William House Cochlear Implant Study Group (CISG) critically examined putative additional benefits of bilateral implantation. The pertinent literature (1-22) was reviewed, and the following position statement was written during a period of several months by an ad hoc committee. It was then discussed at the September 15, 2007 CISG annual meeting of approximately 250 CI professionals. Several improvements were incorporated, and the statement below was recirculated and approved by consensus. Nonetheless, further research is necessary to clarify the usefulness of binaural mechanisms in patients with bilateral CIs and those with combined electrical and contra-lateral acoustic hearing.

Petrous Jugular Malposition (Diverticulum)

Jugular bulb anatomy is variable. A “high-riding” bulb extending into the tympanic cavity is a well-described anomaly. Petrous jugular malposition (diverticulum) (PJMD), however, is rare. The relationship between PJMD and clinical symptoms is questionable because the differentiation between PJMD as an anatomic variant and pathologic process is unproved. A literature review reveals 14 previously documented cases. We report an additional four cases. Diagnostic and management dilemmas are discussed, with the importance of high-resolution CT Stressed.

The Prognostic Value of round Window Electrical Stimulation in Cochlear Implant Patients

The use of preoperative round window stimulation has been advocated for its possible predictive value in cochlear implant patients. We have attempted to correlate cause of deafness, preoperative radiologic study, and postoperative stimulability and performance with preoperative stimulation. Round window stimulation procedures consisted of measurements of electrical thresholds and comfort levels, gap detection, and temporal difference limen. Radiologic studies were performed using high-resolution computerized seml-axial and coronal tomography with 1.5-millimeter overlapping cuts. Patient performance was measured using a standard audiologic test battery. Sixteen postlingually, profoundly deaf adults who received the Nucleus multichannel cochlear implant were studied. All 16 patients who responded to preoperative stimulation had acceptable CT scans for the ear operated on and stimulated postoperatively with the prosthesis. The lowest level at which a patient could reliably detect a gap between two signals ranged from 10 to 150 milliseconds, which was not predictive. For the temporal difference limen task, the patients who could reliably identify the longer of two pulses when the difference was less than 100 milliseconds did achieve varying amounts of open-set speech discrimination postoperatively. In summary, results indicate that the preoperative psychoacoustic electrical stimulation test battery provides useful information in predicting postoperative performance.

Improvement in speech perception and production abilities in children using a multichannel cochlear implant

Nine children received the Nucleus® multichannel cochlear prosthesis. The preoperative evaluation consisted of assessments of auditory function, speech recognition, linguistic skills, and speech production. There were no surgical complications, and recovery in all patients was uneventful. The device was programmed 4 to 5 weeks following surgery, and all children were conditioned to the task. Postoperative training began immediately following device stimulation and is ongoing. Auditory skills and speech production scales were devised to monitor each childs progress. All children have shown varying degrees of improvement in auditory skills and speech production using the implant alone.

Diagnostic and Prognostic Utility of Measuring Tumor Necrosis Factor in the Peripheral Circulation of Patients With Immune-Mediated Sensorineural Hearing Loss

OBJECTIVES To characterize levels of tumor necrosis factor (TNF; formerly known as tumor necrosis factor α), a well-established proinflammatory cytokine, in patients with immune-mediated sensorineural hearing loss (IM-SNHL) and to determine the role of this cytokine in identifying steroid-responsive hearing loss. DESIGN Prospective case-control study. SETTING Tertiary care academic medical center. PATIENTS A total of 11 control subjects and 85 patients with clinical and audiometric characteristics of IM-SNHL (autoimmune inner ear disease and sudden SNHL combined) treated with corticosteroids were enrolled in the study. Patients were categorized as steroid responders (n = 47) and steroid nonresponders (n = 38). Peripheral venous blood was used to determine the total amount of plasma TNF by enzyme-linked immunosorbent assay. Peripheral blood mononuclear cells (PBMCs) were isolated and treated with in vitro dexamethasone. Treated and untreated PBMCs were then analyzed for release of soluble TNF protein into conditioned supernatants as well as expression of TNF messenger RNA (mRNA). MAIN OUTCOME MEASURES Mean plasma levels of TNF, unstimulated and dexamethasone-stimulated PBMC-secreted levels of TNF, and TNF mRNA levels in unstimulated and dexamethasone-stimulated PBMCs. RESULTS Steroid nonresponders had the highest mean baseline plasma levels of TNF compared with steroid responders and control subjects (27.6, 24.1, and 14.4 pg/mL, respectively) (P = .03). For patients with IM-SNHL with a high baseline plasma levels of TNF (>14.4 pg/mL), the mean TNF secreted by PBMCs was 59.1 pg/mL, which decreased to 7.2 pg/mL with in vitro dexamethasone stimulation in the responder group, while the mean TNF secreted by PBMCs was 11.2 pg/mL, which slightly increased to 11.7 pg/mL with in vitro dexamethasone stimulation in the nonresponder group (P = .04). CONCLUSIONS The level of TNF can be used as both a diagnostic and prognostic cytokine for IM-SNHL. For patients presenting with a sudden change in hearing threshold, a high baseline plasma TNF from the peripheral circulation is supportive of the diagnosis if it is greater than 18.8 pg/mL, with a positive predictive value higher than 97%. In addition, this study demonstrates that for patients with IM-SNHL and high plasma levels of TNF, their clinical response to oral glucocorticoids can be predicted by their in vitro PBMC response to dexamethasone. This algorithm may further guide optimal medical treatment and possibly avoid the deleterious adverse effects of administering glucocorticoids to those patients who would not benefit from their effect.