Advancing Cochlear Implant Programming: X-ray Guided Anatomy-Based Fitting.

BACKGROUND: Anatomy-based fitting (ABF) is a new research area in the field of cochlear implants (CIs). Despite the reported benefits and acceptable levels of ABF among CI recipients, some limitations remain, like the postoperative computed tomography (CT) scan, which is preferred for confirming electrode array insertion. OBJECTIVE: This study aimed to investigate the feasibility of using plain film radiography (X-ray) for postoperative electrode detection and for building ABF as an alternative to CT. METHODS: A total of 53 ears with CI were studied. All cases had routine post-insertion X-rays in the cochlear view and additionally underwent postoperative CT. The insertion angles and center frequencies measured by two independent observers were compared for each imaging modality. The angular insertion depth and center frequencies resulting from the X-ray and CT scans were then compared. RESULTS: No significant differences were observed between the X-ray- and CT-measured angles for the electrode contacts. Radiographic measurements between the two readers showed an almost perfect (≥0.8) or substantial (0.71) intraclass correlation coefficient along the electrode contacts. X-ray images showed a mean difference of 4.7 degrees from CT. The mean semitone deviation of the central frequency between the CT and X-ray images was 0.6. CONCLUSIONS: X-ray imaging provides a valid and easy-to-perform alternative to CT imaging, with less radiation exposure and lower costs. The radiographs showed excellent concordance with the CT-measured angular insertion depth and consequently with the central frequency for most electrode contacts. Therefore, plain X-ray could be a viable alternative in building ABF for the CI recipients.

Eustachian Tube Dysfunction Improvement Secondary to Moderate Weight Loss: Case Report.

The Eustachian tube (ET) is an osteocartilaginous canal that connects the middle ear to the nasopharynx. It is one of the critical structures essential for middle ear functions. ET dysfunction causes discomfort in the affected ear and decreased hearing. This is the first case report of improving hearing and middle ear aeration and ET function secondary to body weight reduction. A 27-year-old male patient presented to the otology clinic complaining of decreased hearing for two years. Initial ear examination revealed retraction of TM on the left ear with two retraction pockets, and on the right ear, the TM was dull with one retraction pocket. The patient reported losing some of his body weight during those six months. Ear examination revealed improvement in the TM retraction in both ears. The improvement in hearing was evidenced by a serial audiogram, while the middle ear aeration was evidenced by clinical examination.

Ocular vestibular evoked myogenic potentials n10 response in autism spectrum disorders children with auditory hypersensitivity: an indicator of semicircular canal dehiscence.

UNLABELLED: Sensitivity to sound is one of the most commonly reported challenges in ASD. No compelling evidence shows that hearing of ASD individuals differs physiologically from normal peers. Superior semicircular canal dehiscence was found to be more common in ASD children with auditory hypersensitivity (29%) by means of high-resolution CT scan than the reported (14%) in normal pediatric population by other investigators. The increased prevalence of radiographic dehiscence might be due to inability of CT scan to visualize immature bone. We wished to determine whether ocular vestibular evoked myogenic potentials in ASD children with auditory hypersensitivity produces similar responses to those obtained in adult superior canal dehiscence, and whether it could help differentiate radiographic dehiscence due to bone immaturity from true canal dehiscence syndrome. A prospective study on 14 ASD children complaining of auditory hypersensitivity served as the study group. 15 ASD children without auditory hypersensitivity, age and gender matched, served as a control group. oVEMP and high-resolution CT scan of petrous and temporal bone were performed to all participants. Mean amplitude of n10 was 1.83 ± 0.11 and 1.79 ± 0.09 µV in the control group with mean peak latency of 9.79 ± 0.42 and 9.77 ± 0.30 ms for the right and left ears, respectively. Asymmetry ratio was 2.04 ± 1.37. In the study group, the mean amplitude of n10 was 2.07 ± 0.46 and 1.89 ± 0.30 µV, with mean peak latency of 9.52 ± 0.33 and 9.59 ± 0.21 ms for the right and left ears, respectively, with asymmetry 5.23 ± 6.93%. No statistically significant difference was observed for the studied parameters. In the study group, the number of ears showing an augmented amplitude (>2SD) of n10 was (N = 5). Furthermore, the study group demonstrated a radiographic SSCD in 6 ears. n10 was normal in the control group while radiographic SSCD was observed in 3 of them. CONCLUSION: oVEMPs show diagnostic ability in differentiating ASD children complaining of auditory hypersensitivity due to superior canal dehiscence from those with radiographic dehiscence only due to bone immaturity or atypical cortical development.

Auditory profile and high resolution CT scan in autism spectrum disorders children with auditory hypersensitivity.

Autism is the third most common developmental disorder, following mental retardationand cerebral palsy. ASD children have been described more often as beingpreoccupied with or agitated by noise. The aim of this study was to evaluate theprevalence and clinical significance of semicircular canal dehiscence detected on CTimages in ASD children with intolerance to loud sounds in an attempt to find ananatomical correlate with hyperacusis.14 ASD children with auditory hypersensitivity and 15 ASD children without auditoryhypersensitivity as control group age and gender matched were submitted to historytaking, otological examination, tympanometry and acoustic reflex thresholdmeasurement. ABR was done to validate normal peripheral hearing and integrity ofauditory brain stem pathway. High resolution CT scan petrous and temporal boneimaging was performed to all participated children. All participants had normal hearingsensitivity in ABR testing. Absolute ABR peak waves of I and III showed no statisticallysignificant difference between the two groups, while absolute wave V peak andinterpeak latencies I-V and III-V were shorter in duration in study group whencompared to the control group. CT scans revealed SSCD in 4 out of 14 of the studygroup (29%), the dehiscence was bilateral in one patient and unilateral in threepatients. None of control group showed SSCD. In conclusion, we have reportedevidence that apparent hypersensitivity to auditory stimuli (short conduction time in ABR) despite the normal physiological measures in ASD children with auditoryhypersensitivity can provide a clinical clue of a possible SSCD.

Superior semicircular canal dehiscence syndrome as assessed by oVEMP and temporal bone computed tomography imaging.

To evaluate the role of oVEMP and multidetector CT scan in patients with superior canal dehiscence syndrome. Prospective study was conducted on nine patients with superior canal dehiscence syndrome (5 females, 4 males) age ranged 19-49 with mean age of 32.7 ± 9.3 years, complaining of intolerance to loud sounds and/or oscillopsia. The mean duration of illness was 18.7 ± 6.9 months, nine normal individuals as control (age and gender matched) were also included in the study. All of them underwent oVEMP and MDCT scan. Patients were of bilateral normal hearing sensitivity with no conductive impairment. All of the studied subjects (patients and controls) had identifiable contralateral oVEMP responses. MDCT scan showed dehiscence in all the patients. The dehiscence was unilateral (n = 7) and bilateral [n = 2 the other ear had a defect of 2 mm and thus was excluded from the study for fear or false diagnosis of Superior semicircular canal dehiscence syndrome (SCDS)]. Unlike the normal subject (nI = 0.94 µV ± 0.03 and pI = -0.42 µV ± 0.09), with stimulation of the affected side in SCDS, there were augmented amplitude responses (nI = 2.64 µV ± 0.35 and pI = -3.10 µV ± 0.44) in the eye contralateral to the stimulus "contralateral to the lesion". Mean oVEMP threshold for SCDS ears were 82.5 ± 7.55 dBnHL compared to 100 ± 5.77 dBnHL of the control ears. We concluded that combination of physiological and anatomical information from oVEMP and MDCT increased accuracy for diagnosis of dehiscence of superior semicircular canal.

Transient evoked otoacoustic emissions in superior canal dehiscence syndrome.

Superior semicircular canal dehiscence syndrome (SCDS) is a clinical disorder that is characterized by vertigo and oscillopsia induced by loud sounds. Transient evoked otoacoustic emissions (TEOAEs) allow to noninvasively check the integrity of the cochlea. The present study aimed at identifying cochlear stress as the result of micro alterations of the cochlear functionality due to anatomic anomaly. 11 SCDS and 10 normal individuals as control group were submitted to history taking, otological examination, basic audiologic evaluation and TEOAEs analysis using the standard wideband protocol and moving time window analysis. Although TEOAEs test results showed no statistically significant difference using the standard protocol, off-line analysis of the waveforms' "effective duration" was statistically significantly shortened (p < 0.0001) when compared to normal ears. In conclusion, dehiscence of bone overlying the superior canal has been shown to have effects on inner ear function in terms of a third mobile window theory, thus altering pressure across cochlear partition with decrease in inner ear impedance.