NF2-related schwannomatosis and other schwannomatosis: an updated genetic and epidemiological study.

OBJECTIVES: New diagnostic criteria for NF2-related schwannomatosis (NF2) were published in 2022. An updated UK prevalence was generated in accordance with these, with an emphasis on the rate of de novo NF2 (a 50% frequency is widely quoted in genetic counselling). The distribution of variant types among de novo and familial NF2 cases was also assessed. METHODS: The UK National NF2 database identifies patients meeting updated NF2 criteria from a highly ascertained population cared for by England's specialised service. Diagnostic prevalence was assessed on 1 February 2023. Molecular analysis of blood and, where possible, tumour specimens for NF2, LZTR1 and SMARCB1 was performed. RESULTS: 1084 living NF2 patients were identified on prevalence day (equivalent to 1 in 61 332). The proportion with NF2 inherited from an affected parent was only 23% in England. If people without a confirmed molecular diagnosis or bilateral vestibular schwannoma are excluded, the frequency of de novo NF2 remains high (72%). Of the identified de novo cases, almost half were mosaic. The most common variant type was nonsense variants, accounting for 173/697 (24.8%) of people with an established variant, but only 18/235 (7.7%) with an inherited NF2 pathogenic variant (p<0.0001). Missense variants had the highest proportion of familial association (56%). The prevalence of LZTR1-related schwannomatosis and SMARCB1-related schwannomatosis was 1 in 527 000 and 1 in 1.1M, respectively, 8.4-18.4 times lower than NF2. CONCLUSIONS: This work confirms a much higher rate of de novo NF2 than previously reported and highlights the benefits of maintaining patient databases for accurate counselling.

Incidence and presentation of vestibular schwannoma: a 3-year cohort registry study.

BACKGROUND: Vestibular schwannoma (VS) is the most common benign tumour arising in the lateral skull base. Reported incidence rates of VS vary across geographical locations and over time. There is scarce updated evidence over the past decade on the epidemiology and mode of presentation of VS. OBJECTIVE: To describe the epidemiology and mode of presentation of VS in the East of England between 2013 and 2016. METHODS: A retrospective epidemiological analysis of data from a national VS registry and electronic patient records was conducted, including all newly diagnosed adult patients in a UK tertiary referral centre, between April 1st, 2013, and March 31st, 2016. RESULTS: There were 391 new cases identified resulting in an overall mean incidence of 2.2 VS cases per 100,000 person-year. The incidence rate for all patients in the <40 age group ranged between 0.3 and 0.7 per 100,000 person-year, increasing to a range of 5.7 to 6.1 per 100,000 person-year in the 60-69 age group. The top three combinations of symptoms on presentation per patient were hearing loss and tinnitus (97, 24.8%), hearing loss alone (79, 20.2%) and hearing loss, tinnitus, and balance symptoms (61, 15.6%). The median duration of symptoms was 12 months, with a wide range from 1.4 to 300 months. Age was negatively correlated with tumour size (r = -0.14 [-0.24 to -0.04], p=0.01) and positively correlated with symptom duration (r = 0.16 [0.03-0.29], p=0.02). CONCLUSIONS: The incidence of vestibular schwannoma has increased compared to previous studies in the UK and is similar to incidence rates reported in other countries during the past decade. It peaks in the seventh decade of life, mainly because of an increase in the diagnosis of small tumours with a long duration of audio-vestibular symptoms in older patients, compared to earlier studies.

Frequency of electrode migration after cochlear implantation in the early postoperative period. What are associated risk factors?

OBJECTIVES: To estimate the prevalence of, and risk factors associated with electrode migration (EM) in cochlear implant (CI) recipients. DESIGN: Historical cohort study of all CIs performed between 1 January 2018 and 1 August 2021 in a single tertiary adult and paediatric CI centre in the UK. MAIN OUTCOME MEASURES: The primary aim is to determine the prevalence of electrode migration, comparing intraoperative surgeon report and examination of a routine plain radiograph performed 2 weeks after surgery. EM is defined as the detection of movement of two or more electrodes out of the cochlea from the time of surgery. Multivariate analysis was performed to investigate preoperative and intraoperative risk factors that might predispose to migration. RESULTS: Four hundred and sixty-five patients, having 516 distinct surgeries, with 628 implants were analysed. EM occurred following 11.5% of implant operations. Pre-existing cochlear abnormality was an independent associated risk factor for EM (OR: 3.40 ⟨1.20-9.62⟩ p = .021). Demographics, surgical technique, usage of a precurved electrode, CSF leak, surgeon seniority and intraoperative telemetry did not influence risk of migration. There were 5 implants (0.8%) which migrated later than 2 weeks, with a median date of imaging diagnosis (x-ray or CT scan) of 263 days ⟨IQR:198⟩, for which head injury was a common precipitating factor. There were differences in the risk of migration between different lateral wall electrodes. CONCLUSION: EM in the early postoperative period is a common occurrence and is more likely in implant recipients with obstructed or malformed cochleae.

Cochlear Implantation in Elderly Patients: Survival Duration, Hearing Outcomes, Complication Rates, and Cost Utility.

INTRODUCTION: The prevalence of hearing loss and its consequences is increasing as the elderly population grows. As the guidelines for cochlear implantation (CI) expand, the number of elderly CI recipients is also increasing. We report complication rates, survival duration, and audiological outcomes for CI recipients aged 80 years and over and discuss the cost utility of CI in this age group. METHODS: A retrospective cohort study was undertaken of all CI recipients (126 cases), aged 80 years and over at the time of their surgery, implanted at our institution (Cambridge University Hospitals) during a period from January 1, 2001, to March 31, 2019. Data on survival at 1, 3, and 5 years post-implantation, post-operative complications and functional hearing outcomes including audiometric and speech discrimination outcomes (Bamford-Kowal-Bench sentence test) have been reported. RESULTS: The mean age at implantation was 84 years. The mean audiometric score improved from 108 dB HL to 28 dB HL post-implantation. The mean Bamford-Kowal-Bench score improved from 14% to 66% and 73% at 2 and 12 months post-implantation, respectively. The complication rate was 15.3%. The survival probability at 1 year post-implantation was 0.95 for females and 0.93 for males, at 3 years was 0.89 for females and 0.81 for males, and at 5 years was 0.74 for females and 0.54 for males. CONCLUSION: CI is safe and well-tolerated in this age group and elderly patients gain similar audiometric and functional benefit as found for younger age groups.

Prevalence of occult nodal metastases in squamous cell carcinoma of the temporal bone: a systematic review and meta-analysis.

PURPOSE: Primary: To determine the rate of occult cervical metastases in primary temporal bone squamous cell carcinomas (TBSSC). Secondary: to perform a subgroup meta-analysis of the risk of occult metastases based on the clinical stage of the tumour and its risk based on corresponding levels of the neck. METHODS: A systematic review and meta-analysis of papers searched through Medline, Cochrane, Embase, Scopus and Web of Science up to November 2021 to determine the pooled rate of occult lymph node/parotid metastases. Quality assessment of the included studies was assessed through the Newcastle-Ottawa scale. RESULTS: Overall, 13 out of 3301 screened studies met the inclusion criteria, for a total of 1120 patients of which 550 had TBSCC. Out of the 267 patients who underwent a neck dissection, 33 had positive lymph nodes giving a pooled rate of occult metastases of 14% (95% CI 10-19%). Occult metastases rate varied according to Modified Pittsburg staging system, being 0% (0-16%) among 12 pT1, 7% (2-20%) among 43 pT2 cases, 21% (11-38%) among 45 pT3, and 18% (11-27%) among 102 pT4 cases. Data available showed that most of the positive nodes were in Level II. CONCLUSION: The rate of occult cervical metastases in TBSCC increases with pathological T category with majority of nodal disease found in level II of the neck.

Detecting and managing partial shorts in Cochlear implants: A validation of scalp surface potential testing.

OBJECTIVE: To investigate the value of scalp surface potentials to identify and manage partial short circuits to ground in cochlear implant electrodes. DESIGN: A retrospective review of patients with suspected partial short circuits. MAIN OUTCOME MEASURE: Electrical output of individual electrodes was measured using scalp surface potentials for patients reporting a change in hearing function. Electrical output was compared to functional performance and impedance measurements to determine if devices with suspected partial short circuits were experiencing a decrease in performance as a result of reduced electrical output. Electrical output was checked in an artificial cochlea for two implants following explant surgery to confirm scalp surface potential results. RESULTS: All patients with suspected partial short circuits (n = 49) had reduced electrical output, a drop in impedances to approximately ½ of previously stable measurements or to below 2 kΩ, an atypical electrical field measurement (EFI) and a decline in hearing function. Only devices with an atypical EFI showed reduced electrical output. Results of scalp based surface potentials could be replicated in an artificial cochlea following explantation of the device. All explant reports received to date (n = 42) have confirmed partial short circuits, with an additional four devices failing integrity tests. CONCLUSION: Surface potential measurements can detect partial shorts and had 100% correlation with atypical EFI measurements, which are characteristic of a partial short to ground in this device. Surface potentials can help determine the degree to which the electrode array is affected, particularly when behavioural testing is limited or not possible.

Incidence of mosaicism in 1055 de novo NF2 cases: much higher than previous estimates with high utility of next-generation sequencing.

PURPOSE: To evaluate the incidence of mosaicism in de novo neurofibromatosis 2 (NF2). METHODS: Patients fulfilling NF2 criteria, but with no known affected family member from a previous generation (n = 1055), were tested for NF2 variants in lymphocyte DNA and where available tumor DNA. The proportion of individuals with a proven or presumed mosaic NF2 variant was assessed and allele frequencies of identified variants evaluated using next-generation sequencing. RESULTS: The rate of proven/presumed mosaicism was 232/1055 (22.0%). However, nonmosaic heterozygous pathogenic variants were only identified in 387/1055 (36.7%). When variant detection rates in second generation nonmosaics were applied to de novo cases, we assessed the overall probable mosaicism rate to be 59.7%. This rate differed by age from 21.7% in those presenting with bilateral vestibular schwannoma <20 years to 80.7% in those aged ≥60 years. A mosaic variant was detected in all parents of affected children with a single-nucleotide pathogenic NF2 variant. CONCLUSION: This study has identified a very high probable mosaicism rate in de novo NF2, probably making NF2 the condition with the highest expressed rate of mosaicism in de novo dominant disease that is nonlethal in heterozygote form. Risks to offspring are small and probably correlate with variant allele frequency detected in blood.

Identifying the deficiencies of current diagnostic criteria for neurofibromatosis 2 using databases of 2777 individuals with molecular testing.

PURPOSE: We have evaluated deficiencies in existing diagnostic criteria for neurofibromatosis 2 (NF2). METHODS: Two large databases of individuals fulfilling NF2 criteria (n = 1361) and those tested for NF2 variants with criteria short of diagnosis (n = 1416) were interrogated. We assessed the proportions meeting each diagnostic criterion with constitutional or mosaic NF2 variants and the positive predictive value (PPV) with regard to definite diagnosis. RESULTS: There was no evidence for usefulness of old criteria "glioma" or "neurofibroma." "Ependymoma" had 100% PPV and high levels of confirmed NF2 diagnosis (67.7%). Those with bilateral vestibular schwannoma (VS) alone aged ≥60 years had the lowest confirmation rate (6.6%) and reduced PPV (80%). Siblings as a first-degree relative, without an affected parent, had 0% PPV. All three individuals with unilateral VS and an affected sibling were proven not to have NF2. The biggest overlap was with LZTR1-associated schwannomatosis. In this category, seven individuals with unilateral VS plus ≥2 nondermal schwannomas reduced PPV to 67%. CONCLUSIONS: The present study confirms important deficiencies in NF2 diagnostic criteria. The term "glioma" should be dropped and replaced by "ependymoma." Similarly "neurofibroma" should be removed. Dropping "sibling" from first-degree relatives should be considered and testing of LZTR1 should be recommended for unilateral VS.

A systematic review on prevention and management of wound infections from cochlear implantation.

OBJECTIVE OF REVIEW: Surgical site infections are a recognised complication of cochlear implant (CI) surgery with significant morbidity. Our aim was to search for the optimum prevention and management strategy to deal with this issue. TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: A systematic literature search was undertaken from the databases of Embase, CINAHL, MEDLINE® , Web of Science, Scopus and Cochrane Library according to the predefined inclusion and exclusion criteria. EVALUATION METHOD: All relevant titles, abstracts and full-text articles were reviewed by two authors who resolved any differences by discussion and consultation with senior authors. RESULTS: Fourteen articles were included in our review. The overall quality of evidence was low with the vast majority of the studies being retrospective case series and expert opinions. No randomised controlled trials were noted. We found consistent reports that intraoperative prophylactic antibiotics should be given to all patients undergoing CI and that the vast majority of CI wound infections had grown Staphylococcal spp. or Pseudomonas spp. CONCLUSION: Our review has not identified any reliable or reproducible strategies to prevent and deal with wound infections after CI. We strongly encourage further research within this field and would suggest that a consensus of opinions from a multidisciplinary panel of experts may be a pragmatic way forward as an effective guide.

A comparison of semi-automated volumetric vs linear measurement of small vestibular schwannomas.

OBJECTIVE: Accurate and precise measurement of vestibular schwannoma (VS) size is key to clinical management decisions. Linear measurements are used in routine clinical practice but are prone to measurement error. This study aims to compare a semi-automated volume segmentation tool against standard linear method for measuring small VS. This study also examines whether oblique tumour orientation can contribute to linear measurement error. STUDY DESIGN: Experimental comparison of observer agreement using two measurement techniques. SETTING: Tertiary skull base unit. PARTICIPANTS: Twenty-four patients with unilateral sporadic small (< 15 mm maximum intracranial dimension) VS imaged with 1 mm-thickness T1-weighted Gadolinium enhanced MRI. MAIN OUTCOME MEASURES: (1) Intra and inter-observer intraclass correlation coefficients (ICC), repeatability coefficients (RC), and relative smallest detectable difference (%SDD). (2) Mean change in maximum linear dimension following reformatting to correct for oblique orientation of VS. RESULTS: Intra-observer ICC was higher for semi-automated volumetric when compared with linear measurements, 0.998 (95% CI 0.994-0.999) vs 0.936 (95% CI 0.856-0.972), p < 0.0001. Inter-observer ICC was also higher for volumetric vs linear measurements, 0.989 (95% CI 0.975-0.995) vs 0.946 (95% CI 0.880-0.976), p = 0.0045. The intra-observer %SDD was similar for volumetric and linear measurements, 9.9% vs 11.8%. However, the inter-observer %SDD was greater for volumetric than linear measurements, 20.1% vs 10.6%. Following oblique reformatting to correct tumour angulation, the mean increase in size was 1.14 mm (p = 0.04). CONCLUSION: Semi-automated volumetric measurements are more repeatable than linear measurements when measuring small VS and should be considered for use in clinical practice. Oblique orientation of VS may contribute to linear measurement error.

Clinical and molecular predictors of mortality in neurofibromatosis 2: a UK national analysis of 1192 patients.

BACKGROUND: Neurofibromatosis 2 (NF2) is an autosomal-dominant tumour predisposition syndrome characterised by bilateral vestibular schwannomas, considerable morbidity and reduced life expectancy. Although genotype-phenotype correlations are well established in NF2, little is known about effects of mutation type or location within the gene on mortality. Improvements in NF2 diagnosis and management have occurred, but their effect on patient survival is unknown. METHODS: We evaluated clinical and molecular predictors of mortality in 1192 patients (771 with known causal mutations) identified through the UK National NF2 Registry. Kaplan-Meier survival and Cox regression analyses were used to evaluate predictors of mortality, with jackknife adjustment of parameter SEs to account for the strong intrafamilial phenotypic correlations that occur in NF2. RESULTS: The study included 241 deaths during 10 995 patient-years of follow-up since diagnosis. Early age at diagnosis and the presence of intracranial meningiomas were associated with increased mortality, and having a mosaic, rather than non-mosaic, NF2 mutation was associated with reduced mortality. Patients with splice-site or missense mutations had lower mortality than patients with truncating mutations (OR 0.459, 95% CI 0.213 to 0.990, and OR 0.196, 95% CI 0.213 to 0.990, respectively). Patients with splice-site mutations in exons 6-15 had lower mortality than patients with splice-site mutations in exons 1-5 (OR 0.333, 95% CI 0.129 to 0.858). The mortality of patients with NF2 diagnosed in more recent decades was lower than that of patients diagnosed earlier. CONCLUSIONS: Continuing advances in molecular diagnosis, imaging and treatment of NF2-associated tumours offer hope for even better survival in the future.

A technique for estimating the occlusion effect for frequencies below 125 Hz.

OBJECTIVES: The level of bone-conducted sound in the auditory meatus is increased at low frequencies by occlusion of the meatus, for example, by the earmold of a hearing aid (HA). Physical measures of this "occlusion effect" (OE) require vibration of the skull. In previous research, either self-voicing or audiometric bone conduction vibrators were used to produce this vibration, with the result that the OE could not be measured for frequencies below 125 Hz. However, frequencies below this can be important for music perception by HA users. The objective was to develop and evaluate a method that gives a lower-bound estimate of the OE for frequencies below 125 Hz. DESIGN: A low-noise amplifier with extended low-frequency response was used to record the output of a miniature microphone inserted into the meatus of participants. The signal came from sounds of the heartbeat and blood flow of the participant, transmitted via bone conduction through the walls of the meatus. A simultaneous recording was made of the carotid pulse to permit time-locked averaging (and hence noise reduction) of the microphone signal. Recordings were made from 7 otologically and audiometrically normal participants, using clinical probe tips to produce the occlusion. Recordings were also made from an overlapping group of 9 participants, using fast-setting impression material to provide a more consistent degree of occlusion. The difference in level of the recorded signal for unoccluded and occluded conditions provided a lower bound for the magnitude of the OE. RESULTS: The mean OE increased with decreasing frequency, reaching a plateau of about 40 dB for frequencies below 40 Hz. For some individual recordings, the OE reached 50 dB for frequencies below 20 Hz. With occlusion, the heartbeat became audible for most participants. CONCLUSIONS: The OE can be very large at low frequencies. The use of HAs with closed fittings, which may be used either to prevent acoustic feedback or to allow amplification of low frequencies, may lead to an unacceptable OE. The authors suggest reducing the OE with the use of a seal deep in the meatus, where the wall of the meatus is more rigid.

Technical considerations and long-term results of endovascular venous stenting to control venous hypertension from meningiomas invading intracranial venous sinuses.

OBJECTIVE: Meningiomas invading the intracranial venous sinuses may cause intracranial venous hypertension, papilledema, and visual compromise. Sinus resection and graft reconstructions, however, add significant complexity to tumor surgery, with the potential for increased morbidity. In this study, the authors explored whether venous sinus stenting might provide an alternative means of controlling venous hypertension that would be sustainable over the long term. METHODS: The authors performed a retrospective review of all 16 patients with intracranial meningiomas who underwent stenting at their institution for venous sinus compromise. At presentation, all had headache and 9 had papilledema. Thirteen patients had 1 meningioma and 3 had 2 or more. Three patients had had previous tumor resection and radiotherapy. One patient had been treated with a lumboperitoneal shunt and radiotherapy. The median length of clinical follow-up was 8 years (range 4 months-18 years). RESULTS: Venous sinus narrowing was often not confined to the site of meningioma, and bilateral transverse sinus narrowing, reminiscent of that seen in idiopathic intracranial hypertension, was present in 7 patients with sagittal sinus meningiomas. Eleven patients had stents placed solely across sinus narrowing caused by meningioma. Five patients had additional stents placed at other sites of venous narrowing at the same time: in one of these patients, a stent was placed across a defect in the sagittal sinus caused by previous surgery, and in the 4 other patients, stents were placed across nontumor narrowings of the transverse sinuses. In 1 patient, the jugular vein was also stented. Nine patients developed symptomatic in-stent restenosis at the meningioma site. Eight had further stenting procedures with variable success in restoring the in-stent lumen. The remaining patient, with a late partial relapse, is being reinvestigated. Papilledema resolved in all patients after stenting. Six patients experienced prolonged and very substantial relief of all symptoms. Five patients had persistent headache despite restoration of the sinus lumen. Five had persistent symptoms associated with resistant in-stent stenosis. There were no significant complications from any of the diagnostic or therapeutic procedures. CONCLUSIONS: In patients who are symptomatic with meningiomas obstructing the venous sinuses, successful stenting of the affected segment can give a good outcome, especially in terms of relieving papilledema. However, further procedures are often necessary to maintain stent patency, other areas of venous compromise frequently coexist, and some patients remain symptomatic despite apparently successful treatment of the index lesion. Long-term surveillance is a requirement.

A Multicenter Validity Study of Four Smartphone Hearing Test Apps in Optimized and Home Environments.

OBJECTIVE: Pure tone audiometry (PTA) is the gold standard for hearing assessment. However, it requires access to specialized equipment. Smartphone audiometry applications (apps) have been developed to perform automated threshold audiometry and could allow patients to perform self-administered screening or monitoring. This study aimed to assess the validity and feasibility of patients using apps to self-assess hearing thresholds at home, with comparison to PTA. METHODS: A multi-center, prospective randomized study was conducted amongst patients undergoing PTA in clinics. Participants were randomly allocated to one of four publicly-available apps designed to measure pure tone thresholds. Participants used an app once in optimal sound-treated conditions and a further three times at home. Ear-specific frequency-specific thresholds and pure tone average were compared using Pearson correlation coefficient. The percentage of app hearing tests with results within ±10 dB of PTA was calculated. Patient acceptability was assessed via an online survey. RESULTS: One hundred thirty-nine participants submitted data. The results of two at-home automated smartphone apps correlated strongly/very strongly with PTA average and their frequency-specific median was within ±10 dB accuracy. Smartphone audiometry performed in sound-treated and home conditions were very strongly correlated. The apps were rated as easy/very easy to use by 90% of participants and 90% would be happy/very happy to use an app to monitor their hearing. CONCLUSION: Judicious use of self-performed smartphone audiometry was both valid and feasible for two of four apps. It could provide frequency-specific threshold estimates at home, potentially allowing assessments of patients remotely or monitoring of fluctuating hearing loss. LEVEL OF EVIDENCE: 2 Laryngoscope, 134:2864-2870, 2024.

Life changing response to successive surgical interventions on cranial venous outflow: A case report on chronic fatigue syndrome.

Recognition of similarities between chronic fatigue syndrome and idiopathic intracranial hypertension (IIH) has raised suggestions that they might be connected, with chronic fatigue syndrome representing a mild version of IIH, sharing many of its symptoms, but without the signature features of elevated intracranial pressure that characterize the complete syndrome. A further development of this idea factors in the effects of a cerebrospinal fluid leak, a known complication of IIH, to explain cases where symptoms seem out of proportion to the apparent physiological disturbance. Cranial venous outflow obstruction has been proposed as the pathological substrate. We describe a patient with multiple symptoms, including headache and disabling fatigue, in which this model guided investigation and treatment. Specifically, CT and catheter venography identified focal narrowings of both jugular and the left brachiocephalic veins. Treatment of brachiocephalic obstruction was not feasible. However, in separate surgical procedures, relief of jugular venous obstruction produced incremental and significant clinical improvements which have proven durable over the length of follow-up. We suggest that investigating chronic fatigue syndrome under this model might not only bring benefit to individual patients but also will provide new insights into IIH and its relationship with spontaneous intracranial hypotension.

Meningitis Risk in Patients with Inner Ear Malformations after Cochlear Implants: A Systematic Review and Meta-Analysis.

OBJECTIVE: The objective of this study is to determine the rate of postoperative meningitis after cochlear implantation in those with inner ear malformations (IEMs) via meta-analysis. DATA SOURCES: Medline, EMBASE, and the Cochrane Library. METHODS: This study was reported following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist. Proportion meta-analysis was conducted through an inverse variance random-effect model based on arcsin transformation and presented as forest plots. Quality assessment of the included studies was performed through the National Institutes of Health Quality Assessment Tool. RESULTS: Overall, 38 of 2966 studies met the inclusion criteria and were included in the analysis. There were 10 cases of meningitis after cochlear implantation in 1300 malformed ears. The overall rate of meningitis after cochlear implantation in IEMs was 0.12% (95% confidence interval, 0.006-0.380%; I2 = 0%). Cases occurred in incomplete partition (n = 5), Mondini deformity (n = 2), common cavity (n = 2), and enlarged internal auditory canal (n = 1). Six of 10 cases of postoperative meningitis occurred with an intraoperative cerebrospinal fluid leak. CONCLUSION: In those with IEMs, the risk of meningitis after cochlear implantation is very low.

The Risk of Meningitis After Cochlear Implantation: A Systematic Review and Meta-Analysis.

OBJECTIVE: This study aims to estimate the rate of postoperative meningitis (both immediate and long-term) in patients following cochlear implants (CIs). It aims to do so through a systematic review and meta-analysis of published studies tracking complications after CIs. DATA SOURCES: MEDLINE, Embase, and Cochrane Library. REVIEW METHODS: This review was performed in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies tracking complications following CIs in patients were included. Exclusion criteria included non-English language studies and case series reporting <10 patients. Bias risk was evaluated using the Newcastle-Ottawa Scale. Meta-analysis was performed through DerSimonian and Laird random-effects models. RESULTS: A total of 116/1931 studies met the inclusion criteria and were included in the meta-analysis. Overall, there were 112 cases of meningitis in 58,940 patients after CIs. Meta-analysis estimated an overall rate of postoperative meningitis of 0.07% (95% confidence interval [CIs], 0.03%-0.1%; I2 = 55%). Subgroup meta-analysis showed this rate had 95% CIs crossing 0% in implanted patients who received the pneumococcal vaccine, antibiotic prophylaxis, those with postoperative acute otitis media (AOM), and those implanted less than 5 years. CONCLUSION: Meningitis is a rare complication following CIs. Our estimated rates of meningitis after CIs appear lower than prior estimates based on epidemiological studies in the early 2000s. However, the rate still appears higher than the baseline rate in the general population. The risk was very low in implanted patients who received the pneumococcal vaccine, antibiotic prophylaxis, received unilateral or bilateral implantations, developed AOM, those implanted with a round window or cochleostomy techniques, and those under 5 years.

Changes in audiovestibular handicap following treatment of vestibular schwannomas.

OBJECTIVE: This study aimed to assess degree of audiovestibular handicap in patients with vestibular schwannoma. METHODS: Audiovestibular handicap was assessed using the Hearing Handicap Inventory, Tinnitus Handicap Inventory and Dizziness Handicap Inventory. Patients completed questionnaires at presentation and at least one year following treatment with microsurgery, stereotactic radiosurgery or observation. Changes in audiovestibular handicap and factors affecting audiovestibular handicap were assessed. RESULTS: All handicap scores increased at follow up, but not significantly. The Tinnitus Handicap Inventory and Dizziness Handicap Inventory scores predicted tinnitus and dizziness respectively. The Hearing Handicap Inventory was not predictive of hearing loss. Age predicted Tinnitus Handicap Inventory score and microsurgery was associated with a deterioration in Dizziness Handicap Inventory score. CONCLUSION: Audiovestibular handicap is common in patients with vestibular schwannoma, with 75 per cent having some degree of handicap in at least one inventory. The overall burden of handicap was, however, low. The increased audiovestibular handicap over time was not statistically significant, irrespective of treatment modality.

Radiation treatment of benign tumors in NF2-related-schwannomatosis: A national study of 266 irradiated patients showing a significant increase in malignancy/malignant progression.

Background: Radiation treatment of benign tumors in tumor predisposition syndromes is controversial, but short-term studies from treatment centers suggest safety despite apparent radiation-associated malignancy being reported. We determined whether radiation treatment in NF2-related schwannomatosis patients is associated with increased rates of subsequent malignancy (M)/malignant progression (MP). Methods: All UK patients with NF2 were eligible if they had a clinical/molecular diagnosis. Cases were NF2 patients treated with radiation for benign tumors. Controls were matched for treatment location with surgical/medical treatments based on age and year of treatment. Prospective data collection began in 1990 with addition of retrospective cases in 1969. Kaplan-Meier analysis was performed for malignancy incidence and survival. Outcomes were central nervous system (CNS) M/MP (2cm annualized diameter growth) and survival from index tumor treatment. Results: In total, 1345 NF2 patients, 266 (133-Male) underwent radiation treatments between 1969 and 2021 with median first radiotherapy age of 32.9 (IQR = 22.4-46.0). Nine subsequent CNS malignancies/MPs were identified in cases with only 4 in 1079 untreated (P < .001). Lifetime and 20-year CNS M/MP was ~6% in all irradiated patients-(4.9% for vestibular schwannomas [VS] radiotherapy) versus <1% in the non-irradiated population (P < .001/.01). Controls were well matched for age at NF2 diagnosis and treatment (Males = 133%-50%) and had no M/MP in the CNS post-index tumor treatment (P = .0016). Thirty-year survival from index tumor treatment was 45.62% (95% CI = 34.0-56.5) for cases and 66.4% (57.3-74.0) for controls (P = .02), but was nonsignificantly worse for VS radiotherapy. Conclusion: NF2 patients should not be offered radiotherapy as first-line treatment of benign tumors and should be given a frank discussion of the potential 5% excess absolute risk of M/MP.