A 15-Year Review of 260 Children With Auditory Neuropathy Spectrum Disorder: I. Demographic and Diagnostic Characteristics.

OBJECTIVES: The aim of the study was to review the demographic and clinical characteristics of all pediatric patients diagnosed with auditory neuropathy spectrum disorder (ANSD) by a pediatric health care system from 2005 to 2020 and examine whether or not our diagnostic capabilities in an ANSD population have evolved as our institutional experience has grown and knowledge in the field has expanded. DESIGN: This was a retrospective study reviewing the demographic data, medical history, imaging studies, audiological and speech-language data, type of audiological intervention and mode of communication in 260 pediatric patients diagnosed with ANSD over a 15-year period. RESULTS: The study revealed that male and female children were equally affected with all levels of hearing detection being represented and that about 40% of affected children were premature and most were admitted to the neonatal intensive care unit. More than a third of our patients presented with a complex medical history and/or neural involvement while about 30% were full-term newborns with normal pregnancy, no prenatal complications or infections, normal birth weight, no neonatal intensive care unit need, no hyperbilirubinemia, no respiratory distress requiring ventilation, and no known syndrome. Review of audiological findings confirms that otoacoustic emissions are not always present in ANSD cases, and that the presence of an abnormal wave V on the auditory brainstem response tracings (only present at high intensities and with an absent intensity/latency function) is not a rare finding and should not immediately be dismissed as not being a case of ANSD. CONCLUSIONS: This review of ANSD diagnosis over a 15-year period clearly reveals the drastic improvements made in the identification of ANSD, with a drastic decrease in the age at diagnosis and a reduction in the percentage of misdiagnosed patients. The study also stresses the need for continued improvement in different areas such as genetic studies and physiological measures to help clinicians distinguish between pre- and postsynaptic ANSD.

Dizziness and Imbalance Across the Lifespan: Findings of a Pediatric and Adult Vestibular Clinic.

OBJECTIVE: To evaluate diagnostic trends in pediatric and adult patients presenting for multidisciplinary subspecialty evaluation of dizziness and imbalance across the lifespan. STUDY DESIGN: Retrospective chart review. SETTING: Single pediatric and single adult academic tertiary care hospital. METHODS: Retrospective review of electronic health record for patients presenting to an adult or pediatric multidisciplinary vestibular clinic from 2017 to 2020, including clinical data, physical therapy evaluation, and audiovestibular testing. RESULTS: A total of 1934 patients aged 1 to 95 were evaluated. Most patients were female (n = 1188, 61%); the largest cohort was in the fifth decade of life (n = 321, 17%). Seventy-six percent of patients (n = 1470) were assigned a pathologic diagnosis. Central causes of dizziness were most common in children and young adults, comprising 38% to 54% of all diagnoses in ages 1 to 30. The proportion of peripheral vestibular disorders increased with age, peaking at 32% in ages 61 to 70. Vestibular migraine was the most common pathologic diagnosis in ages 6 to 20 (n = 110, 39%) and 31 and 50 (n = 69, 17%) regardless of gender, but was more prevalent in females (21% vs 14%; P < .0001). The prevalence of benign paroxysmal positional vertigo (BPPV) increased throughout the lifespan, peaking at age 71 to 80. Meniere's disease (MD) did not occur within the first decade of life, but increased thereafter, peaking at ages 51 to 60. CONCLUSION: Multidisciplinary vestibular evaluation resulted in a diagnosis for the majority of patients. Vestibular diagnoses vary across the lifespan however among most age groups, central disorders, including migraine disorders, outnumber peripheral vestibulopathies. The prevalence of peripheral vestibular disorders such as BPPV and MD increased with age. LEVEL OF EVIDENCE: Level IV.

Cortical Auditory Evoked Potential Testing in Children With Auditory Neuropathy Spectrum Disorder.

PURPOSE: In the present report, we reviewed the role of cortical auditory evoked potentials (CAEPs) as an objective measure during the evaluation and management process in children with auditory neuropathy spectrum disorder (ANSD). METHOD: We reviewed the results of CAEP recordings in 66 patients with ANSD aged between 2 months and 12 years and assessed the relationship between their characteristics (prevalence, morphology, latencies, and amplitudes) and various clinical features, including the mode of medical management. RESULTS: Overall, the CAEPs were present in 85.2% of the ears tested. Factors such as prematurity, medical complexity, neuronal issues, or presence of syndromes did not have an effect on the presence or absence of CAEPs. CAEP latencies were significantly shorter in ears with cochlear nerve deficiency than in ears with a normal caliber nerve. Three different patterns of CAEP responses were observed in patients with bilateral ANSD and present cochlear nerves: (a) responses with normal morphology and presence of both P1-P2complex and N2 components, (b) responses with abnormal morphology and presence of the N2 component but undefined P1-P2complex peak, and (c) entirely absent responses. None of the patients with normal, mild, or moderate degree of hearing loss had a complete absence of CAEP responses. No significant differences were uncovered when comparing the latencies across unaided and aided children and children who later received cochlear implants. CONCLUSIONS: The CAEP protocol used in our ANSD program did inform about the presence or absence of central auditory stimulation. Absent responses typically fit into an overall picture of complete auditory deprivation and all of these children were ultimately offered cochlear implants after failing to develop oral language. Present responses, on the other hand, were acknowledged as a sign of some degree of auditory stimulation but always interpreted with caution given that prognostic implications remain unclear.

Asymmetric Ocular Vestibular Evoked Myogenic Potentials in Pediatric Vestibular Migraine.

OBJECTIVE: Although ocular vestibular evoked myogenic potentials (oVEMP) abnormalities have been associated with vestibular migraine (VM) in adults, no studies have evaluated this in pediatric patients with VM. oVEMP asymmetry with normal cervical VEMP (cVEMP) findings may be a reliable VM biomarker in adults. We characterize VEMP results among pediatric patients with VM and benign recurrent vertigo of childhood (BRVC), a migraine precursor, and compare these results with VEMP findings from pediatric patients with nonmigrainous vestibular diagnoses. METHODS: Four hundred seventy-four pediatric patients were evaluated over a 3-year period in a multidisciplinary pediatric vestibular clinic, 139 of whom met the inclusion criteria. Records were reviewed for history, audiometry, and vestibular testing results. VEMP testing was performed with a 500-Hz tone burst. Based on adult normative data, oVEMP asymmetry was defined as greater than 33% interaural difference; cVEMP asymmetry was defined as greater than 41%. RESULTS: Eighty subjects had VM or BRVC (mean [standard deviation] 12.8 [3.8] yr; range, 4.3-18.2 yr). Fifty-nine subjects received vestibular diagnoses other than VM or BRVC (nonmigrainous group; mean [standard deviation] age, 13.0 [3.6] yr; range, 5.14-18.9 yr). A greater proportion of the VM/BRVC group demonstrated oVEMP asymmetry with normal cVEMP as compared with the nonmigrainous group (22.5% versus 10.1%; p < 0.05). Zero subjects in the VM/BRVC group demonstrated cVEMP asymmetry versus three subjects (4.9%) of the nonmigrainous group. CONCLUSIONS: VM and BRVC are notable causes of migraine-related vertigo among pediatric patients. Of VM/BRVC patients, 22.5% had oVEMP asymmetry with normal cVEMP. Similar to the adult VM population, this finding may be a useful biomarker in the right clinical setting for pediatric VM. LEVEL OF EVIDENCE: 4.

Congenital soft tissue stenosis of the external auditory canal with canal cholesteatoma: Case report and literature review.

Congenital external auditory canal stenosis (EACS) is a spectrum of abnormalities affecting the external and middle ear. We report a 6 year-old patient with EACS affecting the lateral fibrocartilaginous canal that was successfully repaired. This patient highlights a variant of EACS characterized by lateral soft tissue narrowing with normal osseous development. Most previous studies of CAA have described severe forms associated with complete atresia, bony stenosis, and middle ear malformations. Stenosis affecting only the fibrocartilaginous canal is a milder form resulting from premature arrest of the canalization process during embryologic development, and may predispose to cholesteatoma formation.

Gastric pepsin in middle ear fluid of children with otitis media: clinical implications.

Gastroesophageal reflux and extraesophageal reflux have been postulated to be involved in the pathogenesis of otitis media. This is supported by recent studies revealing the presence of gastric pepsin in the middle ear space of children with otitis media but not in control patients without otitis media. Reflux's role in otitis media appears to be most pronounced in younger children and those with purulent effusions.

Lack of association of CT findings and surgical drainage in pediatric neck abscesses.

OBJECTIVE: To evaluate the relationship between neck abscess characteristics on computerized tomography (CT) scan and surgical drainage in pediatric patients. METHODS: Retrospective data warehouse review identified 43 children younger than 19 years admitted to a tertiary care pediatric hospital during the first quarters of 2000 through 2003 who underwent CT imaging for suspicion of head and neck abscesses involving the neck; face; and peritonsillar, retropharyngeal, and parapharyngeal spaces. A total of 45 scans were graded by a radiologist blinded to management. Thickness of the prevertebral soft tissue; location, dimensions, and degree of enhancement of the abscess; patient age; steroid and preadmission antibiotic use; and surgical intervention were recorded. RESULTS: Surgical drainage was performed in 32 of 43 patients (74%). We found no significant correlation between prevertebral soft tissue thickness, abscess dimensions or enhancement on CT scan, and surgical drainage. There was no significant association between surgical drainage and patient age, administration of steroids, or preadmission antibiotic use. CONCLUSIONS: Neck abscess appearance on CT scan did not predict surgical drainage, although prevertebral soft tissue thickness and abscess dimensions may be important features. Abscess enhancement, patient age, and the use of steroids and prehospitalization antibiotics were not found to correlate with surgical drainage.

Pediatric cartilage interleave tympanoplasty.

OBJECTIVE: To describe a novel technique of cartilage tympanoplasty, and review surgical and hearing results in children. STUDY DESIGN AND SETTING: Retrospective chart review of all patients who had undergone tympanoplasty at a pediatric tertiary care hospital from August 2002 to July 2005. Forty-two patients were identified with a minimum follow-up time of 12 months. RESULTS: Mean preoperative perforation size was 21.3 percent (range 10%-90%), and mean patient age was 7.9 years (range 3-16 years). Median clinical follow-up was 24 months. Tympanic membrane closure and graft integration were achieved in 40 of 42 patients (95.2%), and 35 of 42 (85.7%) patients maintained an intact, stable tympanic membrane on long-term follow-up. A total of 93.8 percent of patients achieved a postoperative air-bone gap of less than or equal to 20 dB, and mean improvement in the air-bone gap was 10.7 dB. CONCLUSION AND SIGNIFICANCE: Cartilage interleave tympanoplasty is a versatile, stable, and effective technique for tympanic membrane repair in children.

Detection of gastric pepsin in middle ear fluid of children with otitis media.

OBJECTIVE: We sought to confirm the finding of pepsin/pepsinogen in the middle ear fluid of children with otitis media in a larger sample size using a sensitive and specific pepsin assay. STUDY DESIGN AND SETTING: We evaluated 152 children (225 ear samples) in a prospective study at a tertiary care children's hospital. The presence of pepsin in middle ear aspirates was determined using enzymatic assay. RESULTS: Of the patients, 14.4 percent (22 of 152) had detectable pepsin activity in one or both of the ear samples with no pepsin activity detected in control serum. Average pepsin concentration in the samples was 96.6 +/- 170.8 ng/ml, ranging from 13 to 687 ng/ml. Pepsin concentration in the middle ear of children younger than 1.0 year was significantly higher than in older age groups. CONCLUSION AND SIGNIFICANCE: Results indicate that pepsin/pepsinogen is present in the middle ears of children with otitis media, although not at the high rate previously reported. Gastric reflux may be one causative factor in the pathogenesis of otitis media.

Increased incidence of head and neck abscesses in children.

OBJECTIVE: To describe increasing incidence and changing microbiology of head and neck abscesses in children admitted to the hospital during the first quarters of 2000 through 2003. STUDY DESIGN AND SETTING: Retrospective data warehouse review identified 89 children less than 19 years of age admitted to a tertiary care pediatric hospital during the first quarters of 2000 through 2003 for suspicion of head and neck abscess involving the neck, face, and peritonsillar, retropharyngeal, and parapharyngeal spaces; and for orbital and intracranial complications of acute sinusitis. OUTCOME MEASURES: Outcome measures included the incidence of infection admissions and description of infection location and microbiology, calculated by chi2 technique. RESULTS: The incidence of infections increased in 2003. The greatest increase was in neck abscesses and complications of acute sinusitis. CONCLUSIONS: The increase in group A strep infections may be related to its biologic properties. SIGNIFICANCE: Group A strep remains a significant cause of head and neck infections in children.

A pearl in the ear: Intracranial complications of pediatric cholesteatomas.

A nine-year-old male had a cholesteatoma of the mastoid and middle ear found incidentally after myringotomy tube placement. Associated asymptomatic sigmoid plate dehiscence with sinus invasion or thrombosis and ossicular chain destruction complicated his case. He had canal wall down tympanomastoidectomy and was followed for 4.5 years. Disease recurrence necessitated revision. Our case highlights an unusual clinical presentation, possible complications, and the aggressive quality of a benign lesion common in the pediatric population. To our knowledge, this is the first report of an asymptomatic lateral sinus obstruction secondary to an invasive cholesteatoma in this population.

Cochlear Nerve Deficiency and Brain Abnormalities in Pediatric Patients.

HYPOTHESIS: To investigate the intracranial abnormalities present in children with cochlear nerve deficiency (CND), including abnormalities of other cranial nerves, and to describe their auditory abilities. BACKGROUND: The prevalence of CND has increased with the development of high resolution magnetic resonance imaging (MRI). There are varying degrees of CND from true aplasia to hypoplasia. The etiology of CND remains unclear and it may be associated with intracranial abnormalities in some instances. CND needs to be identified as early as possible to ensure prompt and adequate management of hearing loss since hearing aids and cochlear implants may not be an option. METHODS: A retrospective chart review of 56 ears of pediatric patients with CND was conducted between August 2006 and November 2014 at a tertiary care pediatric hospital. RESULTS: 27.6% of children had cochlear abnormalities and 48.9.8% had concomitant vestibular anomalies. Five patients had absent or abnormal facial nerves and two patients had aplastic bilateral olfactory nerves. In the 27 ears with an absent nerve that were functionally tested, eight (29.6%) had partial hearing which indicates the presence of an extremely small nerve whose size is below the limits of spatial resolution of the MRI. CONCLUSION: MRI is becoming the initial imaging choice for children with sensorineural hearing loss to identify CND and other brain anomalies. Concomitant vestibular and cochlear abnormalities were observed in respectively half and one-third of the pediatric patients with CND. The incidence of vestibular malformation suggests that balance testing should be recommended for most if not all CND patients.

Vertically oriented internal auditory canal in an 8-year-old with hearing loss.

To report a unique orientation of the internal auditory canal and possible association with congenital hearing loss. Retrospective chart review of an 8-year-old Hispanic male with a mixed hearing loss. Uniquely abnormal orientation of the internal auditory canal in a patient with apparently normal cochleovestibular structures and a mixed hearing loss. A vertically oriented IAC is a rarely described anatomical anomaly of the temporal bone that may have associations with congenital hearing loss.

Ossiculoplasty using incus interposition: hearing results and analysis of the middle ear risk index.

OBJECTIVE: To determine the immediate hearing result and the long-term stability of sculpted incus interposition in ossiculoplasty and evaluate the utility of the middle ear risk index in predicting hearing outcome in these cases. PATIENTS: One hundred thirty-seven surgical patients. STUDY DESIGN: Review of 137 patients who underwent ossiculoplasty using autologous or homologous sculpted incus interposition. INTERVENTIONS: Ossiculoplasty using autologous or homologous sculpted incus interposition. METHODS: Retrospective chart review, using the guidelines delineated by the Committee on Hearing and Equilibrium of the Academy of Otolaryngology-Head and Neck Surgery for the evaluation of results for the treatment of conductive hearing loss. RESULTS: The mean preoperative air bone gap was 26.8 dB, and the mean postoperative gap was 18.6 dB. Twenty-seven percent of patients were closed to within 10 dB, and 66.4% were brought to within 20 dB of the postoperative bone conduction line. Average time to the last postoperative audiometric testing was 15.8 months, with a range of 2 to 62 months. A mean air bone gap change of -0.2 dB was noted. Four patients had more than a 10 dB deterioration in conductive hearing loss. There were no cases of graft extrusion. Each ear operated upon in our series was fully scored using the middle ear risk index, and an index total was calculated. No statistical associations could be demonstrated in any group between the postoperative air bone gap and the middle ear risk index subcategories or total. CONCLUSIONS: Sculpted autologous or homologous incus interposition provides hearing success comparable with current allograft prosthesis studies, has a very low extrusion rate, and remains stable over time. We were not able to demonstrate an association between the middle ear risk index and hearing results in this subset of patients.

The role of gastric pepsin in the inflammatory cascade of pediatric otitis media.

IMPORTANCE: Otitis media is characterized as an ongoing inflammation with accumulation of an effusion in the middle ear cleft. The molecular mechanisms underlying the pathogenesis, particularly the inflammatory response, remain largely unknown. We hypothesize that aspiration of gastric contents into the nasopharynx may be responsible for the initiation of the inflammatory process or aggravate a preexisting condition. OBJECTIVE: To investigate the correlation of gastric pepsin A with inflammatory cytokines, bacterial infection, and clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS: Prospective study of 129 pediatric patients undergoing myringotomy with tube placement for otitis media at a tertiary care pediatric hospital. MAIN OUTCOMES AND MEASURES: Ear samples were tested for pepsin A; cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor; and bacterial culture inoculation. Data were analyzed by descriptive statistics and regression analysis to identify risk factors for the presence of pepsin A and to correlate pepsin A levels with cytokine levels, infection status, and clinical outcomes. RESULTS: Of the 129 patients, 199 ear samples were obtained; 82 samples (41%) and 64 patients (50%) were positive for pepsin A as measured by immunoassay. Pepsin A positivity correlated with age younger than 3.0 years (mean [SD], 2.3 [2.1] years in the positive group vs 3.3 [3.0] years in the negative group) and with all 3 cytokine levels (mean [SD] tumor necrosis factor, 29.5 [45.9] pg/mL in the positive group vs 13.2 [21.6] pg/mL in the negative group; IL-6, 6791.7 [9389.1] pg/mL in the positive group vs 2849.9 [4066.3] pg/mL in the negative group; and IL-8, 6828.2 [8122.3] pg/mL in the positive group vs 2925.1 [3364.5] pg/mL in the negative group [all P < .05]); however, logistic regression analysis showed that only IL-8 (odds ratio, 3.96; 95% CI, 1.3-12.0; P = .02) and age (odds ratio, 3.83; 95% CI, 1.2-12.7; P = .03) were significant independent variables. No statistically significant association was found with other parameters. Multiple linear regressions revealed that the levels of pepsin A were correlated with IL-8 levels (R2 = 0.248; P < .001) and the need for second or third tubes 6 to 12 months after the first (R2 = 0.102; P = .006). The presence of pepsin A in the middle ear was not associated with increased bacterial infection. Interleukin 8 was independent and significantly associated with both pepsin A levels and bacterial infection (R2 = 0.144 and 0.263, respectively; P = .001 for both). CONCLUSIONS AND RELEVANCE: Extraesophageal reflux as indicated by the presence of pepsin A is closely involved in the middle ear inflammatory process and may worsen the disease in some children; however, a proof of cause and effect between extraesophageal reflux and middle ear inflammation requires further investigation.

Insular carcinoma of the thyroid.

Thyroid surgeons are becoming increasingly more aware of a histologically distinct subset of thyroid carcinoma whose classification falls between well-differentiated and anaplastic carcinomas with respect to both cell differentiation and clinical behavior. This subtype of tumors has been categorized as poorly differentiated or insular carcinoma, based on its characteristic cell groupings. Although the differentiation of insular carcinoma from other thyroid carcinomas has important prognostic and therapeutic significance, relatively little about insular carcinoma has been published in the otolaryngology literature. In this article, we describe a new case of insular carcinoma and we discuss the findings of our review of the literature. We conclude that insular thyroid carcinoma warrants aggressive management with total thyroidectomy followed by radioactive iodine ablation of any remaining thyroid tissue.

A homozygous SLITRK6 nonsense mutation is associated with progressive auditory neuropathy in humans.

OBJECTIVES/HYPOTHESIS: SLITRK family proteins control neurite outgrowth and regulate synaptic development. In mice, Slitrk6 plays a role in the survival and innervation of sensory neurons in the inner ear, vestibular apparatus, and retina, and also influences axial eye length. We provide the first detailed description of the auditory phenotype in humans with recessive SLITRK6 deficiency. STUDY DESIGN: Prospective observational case study. METHODS: Nine closely related Amish subjects from an endogamous Amish community of Pennsylvania underwent audiologic and vestibular testing. Single nucleotide polymorphism microarrays were used to map the chromosome locus, and Sanger sequencing or high-resolution melt analysis were used to confirm the allelic variant. RESULTS: All nine subjects were homozygous for a novel nonsense variant of SLITRK6 (c.1240C>T, p.Gln414Ter). Adult patients had high myopia. The 4 oldest SLITRK6 c.1240C>T homozygotes had absent ipsilateral middle ear muscle reflexes (MEMRs). Distortion product otoacoustic emissions (DPOAEs) were absent in all ears tested and the cochlear microphonic (CM) was increased in amplitude and duration in young patients and absent in the two oldest subjects. Auditory brainstem responses (ABRs) were dys-synchronised bilaterally with no reproducible waves I, III, or V at high intensities. Hearing loss and speech reception thresholds deteriorated symmetrically with age, which resulted in severe-to-profound hearing impairment by early adulthood. Vestibular evoked myogenic potentials were normal in three ears and absent in one. CONCLUSION: Homozygous SLITRK6 c.1240C>T (p.Gln414Ter) nonsense mutations are associated with high myopia, cochlear dysfunction attributed to outer hair cell disease, and progressive auditory neuropathy.

Clinical characteristics of pediatric granular myringitis.

OBJECTIVE: To determine the clinical characteristics of children with granular myringitis. STUDY DESIGN: Case series with chart review of children with granular myringitis. SETTING: Tertiary care children's hospitals in Delaware and Florida. SUBJECTS AND METHODS: From July 1, 2006, to June 30, 2011, 15 patients were identified with granular myringitis based on International Classification of Diseases, Ninth Revision code 384.1 (10 male, 5 female; 10 left-sided, 5 right-sided). RESULTS: Average age at onset was 10 years (range, 4-18 years). Average length of symptoms was 21 months (range, 3-48 months). Thirteen of the 15 patients (87%) had myringotomy tube placement prior to diagnosis of myringitis, and 11 had a previous perforation (73%). Eleven myringoplasties were performed on 8 (53%) patients prior to the onset of granular myringitis (5 fascia, 2 fat, 2 cartilage, 1 paper patch, and 1 at an outside hospital that was unknown). A total of 27 otolaryngologic surgical procedures were done on 14 of 15 patients. Ten patients (67%) had audiometry performed, and 6 (40%) had ear cultures. Medical treatment included ciprofloxacin and dexamethasone otic drops in all patients, oral antibiotics in 4 patients, and additional topical agents in 8 patients. Two patients had laser resurfacing, and 1 patient had surgical curettage. Five patients had long-term remission, 8 had intermittent remission, and 2 had no remission of their symptoms. CONCLUSION: Granular myringitis is a chronic, recalcitrant disease typically preceded by myringotomy and tube placement or myringoplasty/tympanoplasty. Medical and surgical intervention is varied and often does not lead to permanent resolution of the disease.

Clinical characteristics of children with cochlear nerve dysplasias.

OBJECTIVES/HYPOTHESIS: To describe the clinical and audiometric characteristics of children with cochlear nerve dysplasia (CND). STUDY DESIGN: Retrospective chart review of clinical database of children with inner ear anomalies treated at a tertiary care children's hospital. METHODS: Institutional review board-approved retrospective review from June 30, 2006, to July 1, 2011; 18 children were identified with magnetic resonance imaging (MRI) evidence of CND defined as a cochlear nerve 50% smaller than the adjacent facial nerve. RESULTS: Of the 18 patients, nine were girls and nine were boys. Average age at time of MRI diagnosis of CND was 4.6 years. Twelve children had cochlear nerve aplasia, and six had hypoplasia. Three were affected bilaterally: two with aplasia and one with hypoplasia. Unilateral dysplasia was found in 15 children; of these, 60% occurred on the left side. Other inner ear anomalies were found in 50%, including all patients with bilateral CND. Severe-to-profound hearing loss was found in the involved ear(s) in 14 of 18 patients, including all bilateral patients. Of the 18 patients tested, 13 (72%) had an audiometric profile of auditory neuropathy/dys-synchrony syndrome (auditory neuropathy spectrum disorder [ANSD]). Comorbid conditions were present in 56% of patients. Two patients were syndromic. Family history of hearing loss was present in 11% of patients. CONCLUSIONS: Many patients with CND have ANSD, and more than half have comorbidities. Approximately half of affected patients have other inner ear anomalies in the involved ears. Unilateral CND may be more common on the left side.