Blended Phenotype of Pelger-Huet Anomaly with Osteochondroma and Autosomal Recessive Deafness with Enlarged Vestibular Aqueduct

Pelger-Huet anomaly (PHA) is a benign hematological anomaly that is characterized by impaired lobulation of neutrophils with a coarse nuclear chromatin. Skeletal abnormalities may accompany this anomaly. Autosomal recessive deafness-4 (DFNB4) with enlarged vestibular aqueduct (EVA) comprises a phenotypic spectrum of sensorineural hearing loss (SNHL). We report a case with SNHL, multiple skeletal anomalies including osteochondroma, developmental delay, and PHA. Molecular studies revealed a heterozygous pathogenic variant in the <i>LBR</i> gene and a homozygous likely pathogenic variant in the <i>SLC26A4</i> gene. Due to these 2 variants, he was diagnosed with PHA and DFNB4 with EVA. If goiter develops, DFNB4 with EVA is named Pendred syndrome (PDS), so the patient will be followed up for this condition, and in the current literature, there is no case with PDS and PHA co-existence either. PHA may be accompanied by multiple skeletal abnormalities. In our case, there is also concomitance with osteochondroma. Although these are independent and distinct diagnoses, we present this case due to the concomitance of these situations.

A case of Landau-Kleffner syndrome with SLC26A4-related hearing impairment

Background Landau-Kleffner syndrome (LKS) is an acquired aphasia and electroencephalogram (EEG) abnormalities mainly in temporoparietal areas. SLC26A4 mutations can cause hearing loss associated with enlarged vestibular aqueduct (EVA). Case presentations We report a case of LKS in a 5-year-old boy with non-syndromic EVA due to homozygous mutations of c.919-2A>G (IVS7-2A>G) in SLC26A4. He had normal language development before 2 years old. At the age of 2.5 years, he was admitted to the hospital due to remarkable language delay, and diagnosed with hearing loss with EVA. The seizures started at 4.4 years of age and EEG recording showed electrical status epilepticus during sleep (ESES) with a posterior-temporal predominance. He received cochlear implantation in the right ear at 4.7 years of age, which improved his hearing and language skills. The nocturnal focal motor seizures recurred at 4.9 years of age. Then a remarkable inability to respond to calls and reduction in spontaneous speech were noticed. He was treated with methylprednisolone at 5 years old, which controlled the seizures, suppressed ESES, and remarkably improved the language ability. The absence of seizures maintained until the last follow-up at 5.3 years of age, with further improvements in EEG recording and language ability. Conclusions The co-existence of LKS and hearing loss caused by SLC26A4 mutations increases the difficulty of LKS diagnosis, especially in the presence of hearing loss and impaired language skills. EEG discharges predominantly in temporoparietal areas, the occurrence of ESES, and language improvement after antiepileptic medications are potential indicators for LKS diagnosis.

Incomplete Partition type I: Radiological Evaluation of the Temporal Bone

Objective: Incomplete partition type I is an uncommon congenital anomaly of the inner ear, characterized by typical cystic cochleovestibular appearance. Incomplete partition type I was firstly defined as cystic cochlea and vestibule without large vestibular aqueduct; however, large vestibular aqueduct and/or enlarged endolymphatic duct could rarely be seen in incomplete partition type I anomaly. Correct diagnosis of the type of cochlear malformation and differentiation of incomplete partition type I is necessary for patient management and surgical approach. Our aim was to document the temporal bone imaging findings in a series of patients with incomplete partition type I. Materials and Methods: CT (n=85) and/or MRI (n=80) examinations of 99 ears in 59 incomplete partition type I patients were retrospectively evaluated. All structures of the otic capsule were retrospectively assessed. The appearances of cochlea and vestibule, vestibular aqueduct/endolymphatic duct, semicircular canals were qualitatively evaluated by an experienced neuroradiologist. The vertical dimension of vestibular aqueduct and/or endolymphatic duct (from the point where the duct arises from the vestibule) was measured on CT/MRI. Anterior-posterior diameter of the internal acoustic canal and the diameter of cochlear aperture were measured on CT. The cochleovestibular nerves were evaluated on sagittal-oblique high T2-weighted imaging. Results: All 99 ears had defective partition with unpartitioned cochlear basal turn and absent interscalar septae, separated but cystic cochlea. The vestibule was enlarged in all ears except one. Semicircular canals were usually dysplastic (92.9%). A total of 35 incomplete partition type I ears (35.3%) had large vestibular aqueduct and/or enlarged endolymphatic duct. Internal acoustic canal was wide in 21% of ears. Cochlear aperture was wide in 5.9% of ears. Cochlear nerve was either hypoplastic or aplastic in about a quarter of incomplete partition type I ears. Conclusion: In up to one-third of incomplete partition type I patients, an associated large vestibular aqueduct /endolymphatic duct could be seen accompanying typical inner ear findings. Although the cochlear nerves are normal in the majority of cases, auditory brainstem implantation may be necessary in certain cases of incomplete partition type I anomaly.

A novel method of identifying inner ear malformation types by pattern recognition in the mid modiolar section

Identification of the inner ear malformation types from radiographs is a complex process. We hypothesize that each inner ear anatomical type has a uniqueness in its appearance in radiographs. The outer contour of the inner ear was captured from the mid-modiolar section, perpendicular to the oblique-coronal plane, from which the A-value was determined from CT scans with different inner ear anatomical types. The mean A-value of normal anatomy (NA) and enlarged vestibular aqueduct syndrome (EVAS) anatomical types was greater than for Incomplete Partition (IP) type I, II, III and cochlear hypoplasia. The outer contour of the cochlear portion within the mid-modiolar section of NA and EVAS resembles the side view of Aladdin’s lamp; IP type I resembles the side-view of the Sphinx pyramid and type II a Pomeranian dog’s face. The steep spiraling cochlear turns of IP type III resemble an Auger screw tip. Drawing a line parallel to the posterior margin of internal auditory canal (IAC) in axial-view, bisecting the cavity into cochlear and vestibular portions, identifies common-cavity; whereas a cavity that falls under the straight-line leaving no cochlear portion identifies cochlear aplasia. An atlas of the outer contour of seventy-eight inner ears was created for the identification of the inner malformation types precisely.

Clinical Implication of Caloric and Video Head Impulse Tests for Patients With Enlarged Vestibular Aqueduct Presenting With Vertigo

Background: By examining the clinical features and results of video head impulse test (vHIT) and caloric tests in patients with enlarged vestibular aqueduct (EVA) presenting with vertigo, we aimed to investigate the function of angular vestibulo-ocular reflex (VOR) and its clinical implications.Methods: Nine patients with EVA manifesting with vertigo were enrolled. The medical history, audiological examination, imaging, and the results of the caloric test and the vHIT were analyzed.Results: Of the nine patients with EVA (eight bilateral and one unilateral case), five were pediatric cases. All 17 ears exhibited sensorineural hearing loss (SNHL). Enlarged vestibular aqueduct patients can present with recurrent (seven cases) or single (two cases) vertigo attack, trauma-induced (two cases), or spontaneous (seven cases) vertigo. Diminished caloric responses were observed in 77.8% (7/9) of the patients (four cases unilaterally and three bilaterally), while unilateral abnormal vHIT results in 11.1% (1/9) patients. Abnormal caloric and normal horizontal vHIT responses were found in 66.7% (6/9) of EVA patients.Conclusions: Vestibular manifestations in EVA are diverse. Enlarged vestibular aqueduct patients with vertigo can present with a reduced caloric response and normal horizontal vHIT, and this pattern of angular VOR impairment was also found in other hydropic ear diseases.

Objective vestibular function changes in children following cochlear implantation

BACKGROUND: To date, systematically objective evaluations of vestibular function in children with cochlear implantation (CI) have been conducted sparsely, especiallyin children with large vestibular aqueduct syndrome (LVAS). OBJECTIVE: Our goal was to investigate the function of all five vestibular end-organs pre- and post-cochlear implantation in children with LVAS and normal CT. METHODS: In this retrospective cohort study, 34 children (age 4–17 years) with bilateral profound sensorineural hearing loss (SNHL) undergoing unilateral CI were included. Participants included 18 (52.9%) children with LVAS. Objective modalities to evaluate vestibular function included the caloric test, cervical vestibular-evoked myogenic potentials (cVEMP), ocular vestibular-evoked myogenic potentials (oVEMP), and video head impulse test (vHIT). All measurements were performed before surgery and 9 months after surgery. RESULTS: Mean age at CI was 8.1±3.7 years. Caloric testing showed hypofunction in 38.2%of cases before implantation and in 50%after (p > 0.05). We found a significant increase of overall abnormality rate in cVEMP and oVEMP from pre- to post-CI (p < 0.05). In all three semicircular canals tested by vHIT, there were no statistically significant mean gain changes (p > 0.05). Higher deterioration rates in cVEMP (53.3%) and oVEMP (52.0%) after surgery were observed (p < 0.05). In children with LVAS, cVEMP revealed a higher deterioration rate than superior semicircular canal (SSC) and posterior semicircular canal (PSC) (p < 0.05). In children with normal CT, the deterioration rates in VEMPs were both higher than those in vHIT (p < 0.05). CONCLUSIONS: In general, the otolith organs were the most affected peripheral vestibular sensors in children after cochlear implantation. The variations in otolith function influenced by CI were different between children with LVAS and normal CT. We recommend the use of this vestibular function test battery for children with cochlear implantation.