Evaluation of vestibular system in children with labyrinthine aplasia

The aim of this study is to evaluate vestibular system of children with labyrinthine aplasia (study group) who use auditory brainstem implant (ABI) on the single side and compare their findings with healthy children (Control I) and cochlear implant (CI) users with normal inner ear structures (Control II) with age range 4-16 years. There were 30 participants, 10 participants in each three group. Age means of study, Control I and control II group were respectively 9.16 ± 4.02, 9.10 ± 3.96, 9.19 ± 3.25. Video Head Impulse Test (vHIT), Vestibular Evoked Myogenic Potential (VEMP) and Bruininks-Oseretsky Test of Motor Proficiency-2 (BOT-2) Balance subtest were used for vestibular system evaluation. The means of the vestibuloocular reflex (VOR) gain of the study group were significantly lower than control groups (p<0,05). However, the means of anterior canal VOR gain were found partially higher than lateral and posterior canals in the study group. Cervical VEMPs and ocular VEMPs were absent in the study group. And also there was no significant difference between latencies in control groups (p>0.05). BOT-2 balance scores of study (3.70±1.34) and Control II (9.40±2.88) groups were found significantly lower than Control I (16.20±4.16). It was thought that investigating the vestibular system in children with labyrinthine aplasia, which is an extremely rare inner ear malformation, contribute to explain their delay of posturomotor development and to plan vestibular rehabilitation program in early period of their life. Key Words: inner ear malformations, labyrinthine aplasia, Michel deformity, vestibular function, balance