Faculty Bibliography

OBJECTIVECerebral venous sinus thrombosis (CVST) is a known complication of surgeries near the major dural venous sinuses. While the majority of CVSTs are asymptomatic, severe sinus thromboses can have devastating consequences. The objective of this study was to prospectively evaluate the true incidence and risk factors associated with postoperative CVST and comment on management strategies.METHODSA prospective study of 74 patients who underwent a retrosigmoid, translabyrinthine, or suboccipital approach for posterior fossa tumors, or a supratentorial craniotomy for parasagittal/falcine tumors, was performed. All patients underwent pre- and postoperative imaging to evaluate sinus patency. Demographic, clinical, and operative data were collected. Statistical analysis was performed to identify incidence and risk factors.RESULTSTwenty-four (32.4%) of 74 patients had postoperative MR venograms confirming CVST, and all were asymptomatic. No risk factors, including age (p = 0.352), BMI (p = 0.454), sex (p = 0.955), surgical approach (p = 0.909), length of surgery (p = 0.785), fluid balance (p = 0.943), mannitol use (p = 0.136), tumor type (p = 0.46, p = 0.321), or extent of resection (p = 0.253), were statistically correlated with thrombosis. All patients were treated conservatively, with only 1 patient receiving intravenous fluids. There were no instances of venous infarctions, hemorrhages, or neurological deficits. The rate of CSF leakage was significantly higher in the thrombosis group than in the nonthrombosis group (p = 0.01).CONCLUSIONSThis prospective study shows that the radiographic incidence of postoperative CVST is higher than that previously reported in retrospective studies. In the absence of symptoms, these thromboses can be treated conservatively. While no risk factors were identified, there may be an association between postoperative CVST and CSF leak.

OBJECTIVE:To assess auditory brainstem implant (ABI) outcomes in children with a prospective study. METHODS:Twelve patients with cochlear nerve deficiency received an auditory brainstem implant. Patients were evaluated with age appropriate speech perception and production assessments, and health related quality of life (HRQoL) surveys for parents of subjects and for subjects if age appropriate. RESULTS:Twelve patients received an ABI without major complications. Eleven out of twelve received some auditory benefit from their ABI. Parental HRQoL ratings were positive for all domains with the exception of communication. Self reported overall HRQoL metrics from two subjects were also positive. CONCLUSIONS:ABI is a good option for patients who are not eligible for or fail CI. Our findings show that despite varying degrees of postoperative performance, HRQoL ratings were positive. The presence of additional disabilities and health problems resulted in less positive HRQoL outcomes. Our results emphasize the need to assess outcomes in these patients beyond speech perception and communication.

OBJECTIVE:To demonstrate the long-term benefits of implantation in patients with high-frequency sensorineural hearing loss, this report provides 5-year follow-up on a group of implant recipients who were subjects of the Cochlear™ Nucleus® Hybrid™ L24 Implant System pivotal clinical study. METHODS:The results of three related clinical studies were compiled to provide outcome data after 1, 3, and 5 years of implant use in a group of subjects who presented with preoperative high-frequency hearing loss and were implanted with a Nucleus Hybrid L24 (Cochlear Ltd., Sydney, Australia) cochlear implant. A subset of the 50 adult subjects (N = 32) who participated in the Hybrid L24 pivotal Investigational Device Exemption (IDE) completed comprehensive evaluations at 12 months postactivation, 3 years postactivation, and then as part of a postapproval study at 5 years postactivation. Testing included audiometric, speech perception, and subjective satisfaction measures. RESULTS:Mean unilateral speech perception performance was significantly improved at all postoperative intervals compared to preoperative best-aided results and has remained stable to 5 years postactivation. Ninety-four percent of subjects had measurable hearing, and 72% continued to use electric-acoustic stimulation in the implanted ear after 5 years of implant use. Subjective satisfaction results support objective performance improvements. CONCLUSION/CONCLUSIONS:Results demonstrate long-term success of patients with high-frequency hearing loss following Hybrid L24 (Cochlear) cochlear implantation. Benefits include speech perception abilities significantly better than those in the preoperative best-aided condition, with additional benefit in those using electric-acoustic stimulation in the implanted ear. LEVEL OF EVIDENCE/METHODS:2b. Laryngoscope, 2018.

BACKGROUND:Hearing preservation is a goal for many patients with vestibular schwannoma. We examined pretreatment magnetic resonance imaging (MRI) and posttreatment hearing outcome after stereotactic radiosurgery. METHODS:From 2004 to 2014, a cohort of 125 consecutive patients with vestibular schwannoma (VS) treated via stereotactic radiosurgery (SRS) were retrospectively reviewed. MRIs containing three-dimensional constructive interference in steady state or equivalent within 1 year before treatment were classified by two radiologists for pretreatment characteristics. "Good" hearing was defined as American Academy of Otolaryngology-Head and Neck Surgery class A. Poor hearing outcome was defined as loss of good pretreatment hearing after stereotactic radiosurgery. RESULTS:Sixty-one patients met criteria for inclusion. Most had tumors in the distal internal auditory canal (55%), separated from the brainstem (63%), oval shape (64%) without cysts (86%), and median volume of 0.85 ± 0.55 cm. Pretreatment audiograms were performed a median of 108 ± 173 days before stereotactic radiosurgery; 38% had good pretreatment hearing. Smaller tumor volume (p < 0.005) was the only variable associated with good pretreatment hearing. 49 (80%) patients had posttreatment audiometry, with median follow-up of 197 ± 247 days. Asymmetrically decreased pretreatment cochlear CISS signal on the side of the VS was the only variable associated with poor hearing outcome (p = 0.001). Inter-rater agreement on cochlear three-dimensional constructive interference in steady state preservation was 91%. CONCLUSIONS:Decreased cochlear CISS signal may indicate a tumor's association with the cochlear neurovascular bundle, influencing endolymph protein concentration and creating an inability to preserve hearing. This important MRI characteristic can influence planning, counseling, and patient selection for vestibular schwannoma treatment.

OBJECTIVE:To assess bimodal auditory performance in children with a cochlear implant (CI) and contralateral auditory brainstem implant (ABI). METHODS:This is a retrospective case review performed at a tertiary referral center. Four patients with cochlear nerve deficiency initially underwent cochlear implantation but were not benefiting from their devices and underwent ABI in the contralateral ear. The main outcome measures included age-appropriate speech perception and production assessments. RESULTS:Three subjects performed better on their auditory perception assessments using both of their devices than with either device alone. One subject had only preliminary outcomes, but subjectively performed best with both devices. CONCLUSIONS:We observed continued improvement in CI performance over time, even if no benefit was evident before the decision for ABI. This could suggest that ABI and CI have a synergistic effect, or it could simply be the adaptive ability of the developing brain to utilize the signals coming from these devices. There is preliminary evidence to support choosing the ear contralateral to the CI for an ABI in a pediatric patient with bilateral cochlear nerve deficiency.

Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, and Ear abnormalities and deafness (CHARGE) syndrome is a disorder with multiple congenital anomalies seen on imaging. A retrospective review of 10 patients with CHARGE syndrome who underwent MR imaging of the brain as part of a preoperative evaluation for cochlear implantation was conducted. Structural abnormalities of the entire MR imaging of the head were evaluated, including the auditory system, olfactory system, face, skull base, and central nervous system. The most frequent MR imaging findings included dysplasias of the semicircular canals and hypoplasia of the frontal lobe olfactory sulci. Less frequent findings included cleft lip/palate and coloboma. Our study uncovered new findings of a J-shaped sella, dorsal angulation of the clivus, and absent/atrophic parotid glands, not previously described in patients with CHARGE. Our results emphasize the utility of MR imaging in the diagnosis and management of patients with CHARGE syndrome.

OBJECTIVE: To evaluate the safety, efficiency, cost effectiveness, and satisfaction of patients undergoing cochlear implantation under conscious sedation versus general anesthesia. STUDY DESIGN: Retrospective case review of 20 patients who underwent cochlear implantation under conscious sedation which was compared to 20 age-matched patients where surgery was performed under general anesthesia. METHODS: Perioperative times, length of stay, anesthesia drug costs, postoperative complications, and patient satisfaction were compared between the two groups. RESULTS: Conscious sedation was associated with decreased drug costs, surgery time, and anesthesia time. Length of stay was significantly longer for patients undergoing general anesthesia. Patient satisfaction was superior with conscious sedation. Perioperative morbidity was not significantly different between the two groups. CONCLUSION: Conscious sedation for cochlear implantation is a safe, efficient, and cost-effective alternative to general anesthesia. The efficacy of conscious sedation for cochlear implant surgery may expand the treatment of profound hearing loss to the elderly who are deemed too sick for general anesthesia or are fearful of the cognitive or medical consequences of general anesthesia.

OBJECTIVE: To compare the intraoperative electrically evoked auditory brainstem response (EABR) morphologies between neurofibromatosis II (NF2) adult auditory brainstem implant (ABI) recipients who had auditory percepts post-operatively and those who did not and between NF2 adult ABI recipients and non-NF2 pediatric ABI recipients. METHODS: This was a retrospective case series at a single tertiary academic referral center examining all ABI recipients from 1994 to 2016, which included 34 NF2 adults and 11 non-NF2 children. The morphologies of intraoperative EABRs were evaluated for the number of waveforms showing a response, the number of positive peaks in those responses, and the latencies of each of these peaks. RESULTS: 27/34 adult NF2 patients and 9/10 children had EABR waveforms. 20/27 (74.0%) of the adult patients and all of the children had ABI devices that stimulated post-operatively. When comparing the waveforms between adults who stimulated and those who did not stimulate, the proportion of total number of intraoperative EABR peaks to total possible peaks was significantly higher for the adults who stimulated than for those who did not (p < 0.05). Children had a significantly higher proportion of total number of peaks to total possible peaks when compared to adults who stimulated (p < 0.02). Additionally, there were more likely to be EABR responses at the initial stimulation than intraoperatively in the pediatric ABI population (p = 0.065). CONCLUSIONS: The value of intraoperative EABR tracing may lie in its ability to predict post-operative auditory percepts based on the placement of the array providing the highest number of total peaks.

OBJECTIVE: To characterize the performance plateau after unilateral cochlear implantation (CI) in prelingually and postlingually deafened adults and to compare their relative progress. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Prelingually and postlingually deaf adults who received a unilateral CI and completed a minimum of 2 years of follow-up at our center. INTERVENTION: Unilateral CI. MAIN OUTCOME MEASURES:: Standard speech perception testing (consonant-nucleus-consonant [CNC] monosyllabic word test and hearing in noise test [HINT] or AzBio sentence test) were performed preoperatively and 3 and 12 months postoperatively, and annually thereafter. RESULTS: In postlingually deaf patients (n = 102), there was a significant improvement in word scores for 3 years postimplantation (p < 0.01). Beyond the 3 years postoperative time point, word scores continued to improve, albeit at a flatter rate. In prelingually deaf patients (n = 16) word scores improved significantly for 5 years postimplantation (p = 0.03). CONCLUSIONS: Adults with postlingual deafness undergoing unilateral CI show significant improvement in speech perception for 3 years postimplantation, at which point their performance continues to improve, albeit at a flatter rate. The performance of adults with prelingual deafness improves significantly as late as 5 years postimplantation. These time intervals reflect a change to the currently reported 6 to 12 months period and should impact on counseling, especially in the prelingual CI candidate.