Anil K. Lalwani

Speech perception benefits of sequential bilateral cochlear implantation in children and adults: a retrospective analysis.

Objective: To examine speech perception outcomes and determine the impact of length of deafness and time between implants on performance in the sequentially bilateral implanted population. Study Design: Retrospective review. Setting: Tertiary academic referral center. Patients: Forty-three children (age, <18 yr) and 22 adults underwent sequential bilateral implantation with at least 6 months between surgeries. The mean age at the time of the second implant in children was 7.83 years, and mean time between implants was 5.16 years. Five children received the first side implant (C1) below 12 months of age; 16, at 12 to 23 months; 9, between the ages of 24 and 35 months; and 11, at 36 to 59 months; 2 were implanted above the age of 5 years. In adults, mean age at second implant was 46.6 years, and mean time between implants was 5.6 years. Intervention: Sequential implantation with 6 months or more between implantations. Main Outcome Measures: Speech perception tests were performed preoperatively before the second implantation and at 3 months postoperatively. Results: Results revealed significant improvement in the second implanted ear and in the bilateral condition, despite time between implantations or length of deafness; however, age of first-side implantation was a contributing factor to second ear outcome in the pediatric population. Conclusion: Sequential bilateral implantation leads to significantly better speech understanding. On average, patients improved, despite length of deafness, time between implants, or age at implantation.

Significance of House-Brackmann facial nerve grading global score in the setting of differential facial nerve function

Objective To determine the clinical significance of the House-Brackmann facial nerve grading scale (HBFNGS) in the setting of differential function along the branches of the facial nerve. Study Design Prospective study of 38 patients with facial palsy who demonstrated differential facial function. Setting Tertiary referral center. Patients Patients with facial nerve dysfunction from any cause. Patients with complete facial nerve paralysis (House-Brackmann Grade 6) were excluded. Intervention Physicians were provided with printed description of the HBFNGS and asked to report facial nerve function as a traditional global score and as a regional score based on the House-Brackmann scale for the forehead, eye, nose, and mouth. This was reported as FwExNyMz, where w, x, y, and z ranged from 1 to 6 based on the HBFNGS. Synkinesis was graded as none, mild, or severe. Main Outcome Measures The traditional HBFNGS score was compared with a regional grading facial nerve grading system based on the HBFNGS for the forehead, eye, nose, and mouth. Agreement between the traditional global score and the regional scores was analyzed. Results In patients with variable facial weakness, the single House-Brackmann score did not fully communicate their facial function. Further, the single grade did not always correlate with the best or worst function along the four facial regions. The single House-Brackmann score most strongly correlated with the regional scoring of the eye (61%), followed by the nose/midface (40%), mouth (32%), and forehead (18%). The global score did not correlate with the worst regional score in 30 patients (79%). In 3 of 5 patients with synkinesis and an obligatory Grade 3 or higher in the global House-Brackmann grading system, the regional facial function was Grade 2 or better at one or more areas of the face. Conclusions In patients with differential facial function, a single global number is inadequate to describe facial function and primarily reflects the function of the eye. Regional assessment using the HBFNGS and reported as FwExNyMz more fully communicates facial function.

Conservative Management of Infections in Cochlear Implant Recipients

OBJECTIVE: The goal of this study was to evaluate a conservative management strategy of postoperative infection after cochlear implantation. METHODS: A retrospective review of the medical records of 108 cochlear implant patients operated on at the University of California, San Francisco between 1991 and 2000 and 133 cochlear implant patients from the University of Iowa between 1997 and 2000 showed 4 patients with evidence of postoperative infections. The clinical presentation, intervention, laboratory results, and outcome are analyzed in each case. RESULTS: Minimal surgical intervention with limited incision and drainage with prolonged postoperative antibiotics was effective in treating postoperative cochlear implant infections without the need for device removal. Implant function remained unaffected after surgery. CONCLUSION: Postoperative cochlear implant infections can be effectively controlled with limited surgical and prolonged medical management. Chronic implant infections may be explained by a primary immunodeficiency. With appropriate treatment leading to infection control, a conservative management strategy is advocated before consideration of device explantation.

Preoperative differentiation between meningioma of the cerebellopontine angle and acoustic neuroma using MRI.

Preoperative differentiation between acoustic neuroma (AN) and meningioma of the cerebellopontine angle (CPA) is important in selection of the surgical approach, successful tumor removal, and preservation of hearing and facial nerve. We retrospectively reviewed the magnetic resonance imaging (MRI) findings associated with 30 meningiomas involving the CPA (MCPA) encountered between 1987 to 1991 at the University of California, San Francisco. Magnetic resonance imaging was critical in differentiating meningioma from AN in the CPA. Typical findings on MRI associated with MCPA, differentiating them from ANs, Include: Meningiomas are sessile, possessing a broad base against the petrous face, whereas ANs are globular; they are often extrinsic and eccentric to the internal auditory canal (IAC); when involving the IAC, they usually do not erode the IAC; MCPAs demonstrate hyperostosis of the subjacent bone and possess intratumoral calcification; they involve adjacent intracranial spaces and structures; and meningiomas are characterized by a distinctive dural “tail” extending away from the tumor surface. While any one finding may not be diagnostic by itself, taken together the constellation of these findings is strongly Indicative of meningioma. In our experience, MRI with gadolinium enhancement was able to distinguish MCPA from AN in nearly every case.

Intraoperative neural response telemetry as a predictor of performance.

Objective: To determine whether intraoperative neural response telemetry (tNRT) is predictive of postoperative speech perception. Study Design: Retrospective review. Setting: Tertiary referral center. Patients: Children (n = 24) aged between 5 and 17 years and adults 18 years and older (n = 73) with severe-to-profound hearing loss and implanted with the Nucleus Freedom device between 2005 and 2008 and observed at least 1 year were included. Intervention: Intraoperative neural response telemetry after insertion of the electrode array. Main Outcome Measure: Measures included 1) intraoperative tNRT measurements and 2) preoperative and 1-year postoperative open-set word recognition scores using age-appropriate open-set tests for children and adults. Intraoperative neural response telemetry levels for electrodes E20, E15, E10, and E5 in each patient were correlated to performance at the 1-year evaluation interval. Results: No correlation existed between tNRT responses and open-set speech performance at the 1-year evaluation. Several patients had absent tNRT in the OR but developed speech recognition abilities, whereas the remaining patients had intraoperative responses with levels of postoperative performance ranging from 0% to 100%. Conclusion: This study suggests that there is no significant correlation between intraoperative tNRT and speech perception performance at 1 year. At the time of surgery, tNRT provides valuable information regarding the electrical output of the implant and the response of the auditory system to electrical stimulation and preliminary device programming data; however, it is not a valuable predictor of postoperative performance. Furthermore, the absence of tNRT does not necessarily indicate a lack of stimulation.

Development of the Jugular Bulb: A Radiologic Study

Objective: Jugular bulb (JB) abnormalities such as JB diverticulum and high-riding JBs of the temporal bone can erode into the inner ear and present with hearing loss, vestibular disturbance, and pulsatile tinnitus. Their cause and potential to progress remain to be studied. This comprehensive radiologic study investigates the postnatal development of the venous system from transverse sinus to internal jugular vein (IJV). Setting: Academic medical center. Patients, Intervention, Main Outcome Measure: Measurements of the transverse and sigmoid sinus, the JB, IJV, and carotid artery were made from computed tomographic scans of the neck with intravenous contrast in infants (n = 5), children (n = 13), adults (n = 35), and the elderly (n = 15). Results: Jugular bulbs were not detected in patients younger than 2 years, enlarged in adulthood, and remained stable in the elderly. The venous system was larger in men than in women. From transverse sinus to IJV, the greatest variation in size was just proximal and distal to the JB with greater symmetry observed as blood returned to the heart. Right-sided venous dominance was most common occurring in 70% to 80% of cases. Conclusion: The JB is a dynamic structure that forms after 2 years, and its size stabilizes in adulthood. The determinants in its exact position and size are multifactorial and may be related to blood flow. Improved understanding of this structures development may help to better understand the cause of the high-riding JB and JB diverticulum, both of which may cause clinical symptoms.

Secondhand Smoke and Sensorineural Hearing Loss in Adolescents

OBJECTIVE To investigate the hypothesis that second-hand smoke (SHS) exposure is associated with sensorineural hearing loss (SNHL) in adolescents. DESIGN A complex, multistage, stratified geographic area design for collecting representative data from the noninstitutionalized US population. PARTICIPANTS Cross-sectional data from National Health and Nutrition Examination Survey (2005-2006) were available for 1533 participants 12 to 19 years of age who underwent audiometric testing, had serum cotinine levels available, and were not actively smoking. MAIN OUTCOME MEASURES SNHL was defined as an average pure-tone level greater than 15 dB for 0.5, 1, and 2 kHz (low frequency) and 3, 4, 6, and 8 kHz (high frequency). RESULTS Secondhand smoke exposure, as assessed by serum cotinine levels, was associated with elevated pure-tone hearing thresholds at 2, 3, and 4 kHz, a higher rate of unilateral low-frequency SNHL (11.8% vs 7.5%; P < .04), and a 1.83-fold increased risk of unilateral low-frequency SNHL in multivariate analyses (95% confidence interval, 1.08-3.41). The prevalence of SNHL was directly related to level of SHS exposure as reflected by serum cotinine levels. In addition, nearly 82% of adolescents with SNHL did not recognize hearing difficulties. CONCLUSIONS Secondhand smoke is associated with elevated pure-tone thresholds and an increased prevalence of low-frequency SNHL that is directly related to level of exposure, and most affected individuals are unaware of the hearing loss. Thus, adolescents exposed to SHS may need to be closely monitored for early hearing loss with periodic audiologic testing.

Prevalence of Jugular Bulb Abnormalities and Resultant Inner Ear Dehiscence: a Histopathologic and Radiologic Study:

Objective Jugular bulb abnormalities (JBA), including high-riding jugular bulb (HRJB) and jugular bulb diverticulum (JBD), can erode into the inner ear. In this study, the authors investigate the prevalence and consequences of JBA and their erosion into inner ear structures using temporal bone histopathology and computed tomography (CT). Study Design Cross-sectional study of temporal bone histopathology and radiology. Setting Academic medical center. Subjects and Methods In total, 1579 temporal bone specimens and 100 CT of the temporal bones (200 ears) were examined for JBA and any associated dehiscence of inner ear structures. Temporal bone specimens were examined for histological consequences of inner ear erosion. Jugular bulb dimensions were measured on axial CT scans and compared across groups. Accompanying demographic and clinical information were reviewed. Results High jugular bulbs were noted in 8.2% (130/1579) of temporal bone specimens and in 8.5% (17/200) of temporal bone CT. The prevalence of JBA increases during the first 4 decades of life and stabilizes thereafter. High-riding jugular bulbs eroded inner ear structures such as the vestibular aqueduct, vertical facial nerve, or posterior semicircular canal in 2.8% (44/1579) of cases histologically and 1.5% (3/200) radiologically. In most, jugular bulb–mediated inner ear dehiscence was clinically and radiologically silent. Conclusion Jugular bulb abnormalities are common. They are present in 10% to 15% individuals and are primarily acquired by the fourth decade of life. In 1% to 3% of cases, the HRJB erodes into the inner ear and most frequently involves the vestibular aqueduct.

A Clinical and Histopathologic Study of Jugular Bulb Abnormalities

OBJECTIVE To further define the spectrum of clinical presentation and explore the histologic sequelae of jugular bulb abnormalities (JBAs). DESIGN Retrospective review. SETTING Academic medical center. PATIENTS Thirty patients with radiologic evidence of inner ear dehiscence by JBA. MAIN OUTCOME MEASURE Thirty patients with radiologic inner ear dehiscence by JBA and 1579 temporal bone specimens were evaluated for consequences from JBA. RESULTS We found that JBA-associated inner ear dehiscence could be identified on computed tomography of the temporal bone but not on magnetic resonance imaging scan. Jugular bulb abnormalities eroded the vestibular aqueduct most often (in 25 patients), followed by the facial nerve (5 patients) and the posterior semicircular canal (4 patients). Half of the patients (15) were asymptomatic. Results from vestibular evoked myogenic potential (VEMP) tests were positive in 8 of 12 patients with inner ear dehiscence. Histologically, only 2 of 41 temporal bones with dehiscence of the vestibular aqueduct demonstrated endolymphatic hydrops. CONCLUSIONS Jugular bulb abnormalities can erode into the vestibular aqueduct, facial nerve, and the posterior semicircular canal. While symptoms may include pulsatile tinnitus, vertigo, or conductive hearing loss, in contrast to earlier reports, half of the patients were asymptomatic. Dehiscence of vestibular aqueduct rarely leads to clinical or histologic hydrops. The VEMP testing was useful in confirming the presence of inner ear dehiscence due to JBAs. Because the natural history of JBAs is unknown, these patients should be followed closely to evaluate for progression of the JBA or development of symptoms.

Preoperative and Postoperative Intracranial Complications of Acute Mastoiditis

Objectives: We determined the clinical characteristics and treatment outcomes of an unusual cluster of intracranial complications seen in acute mastoiditis (AM). Methods: We performed a retrospective review of pediatric patients treated for AM in a tertiary care hospital from March 2006 to March 2007. Results: Eleven children, 6 months to 10 years of age (mean age, 3.8 years), were treated for AM confirmed by computed tomography, which identified asymptomatic intracranial complications in 8 of the 11 patients: These were sigmoid sinus thrombosis (4 patients), epidural abscess (4), perisigmoid abscess or bony erosion (2), and tegmen mastoideum dehiscence (1). All patients required operative intervention with tympanomastoidectomy, although only 2 patients required neurosurgical intervention, consisting of evacuation of epidural abscess and sigmoid sinus thrombosis, respectively. Cultures yielded routine organisms and 1 multidrug-resistant strain of Streptococcus pneumoniae. One patient developed reaccumulation of the subperiosteal abscess that required revision mastoidectomy, and another patient developed postoperative sigmoid sinus thrombosis. Conclusions: Although uncommon, intracranial complications of AM may present without clinical signs or symptoms. Computed tomography of the temporal bone with contrast is essential for identifying asymptomatic complications. Mastoidectomy remains the mainstay of surgical treatment. Neurosurgical intervention and anticoagulation may be avoided with protracted postoperative intravenous antibiotics. Postoperative vigilance is crucial, as complications may evolve despite aggressive therapy.