КОМПЛЕКСНАЯ ДИАГНОСТИКА СЛУХА У ДЕТЕЙ С ЗАБОЛЕВАНИЕМ СПЕКТРА АУДИТОРНЫХ НЕЙРОПАТИЙ В РЕСПУБЛИКЕ БЕЛАРУСЬ

Abstract

Auditory Neuropathy Spectrum Disorders, ANSD is a state of the auditory system in which the patient has otoacoustic emissions (OAEs) and/or cochlear microphonic potential (CMP), and auditory brainstem responses (ABRs) are absent or significantly reduced. In contrast to sensorineural hearing loss, where the outer and inner hair cells of the cochlea are damaged, in ANSD the outer hair cells are preserved. The complexity of ANSD detection and the variety of clinical symptoms of this disorder make it difficult to differentiate this disease from sensorineural hearing loss. Purpose. Improvement of the differential diagnosis of ANSD and sensorineural hearing loss by defining the main anamnestic and audiological criteria. Materials and methods. The research included 2 groups of patients: the core group - 48 patients with bilateral ANSD and the control group - 30 patients with bilateral chronic sensorineural hearing loss. All patients underwent assessment of the anamnesis data, impedance measurement, tone threshold audiometry, registration of OAE (TEOAE), registration of ABR with allocation of CMP, registration of stationary auditory evoked potentials. Results. In patients with ANSD the incidence of prematurity, low birth weight, and hyperbilirubinemia is significantly higher (p <0.05) than in patients with sensorineural hearing loss. In patients with ANSD the 35delG mutation in the GJB2 gene was not identified, in contrast to patients with sensorineural hearing loss (genetic factor was confirmed in 23.3%) (p <0.05). Newborn hearing screening on both sides was conducted in 15 children (31.3%) with ANSD and only 1 child (3.3%) with sensorineural hearing loss (p <0.05). In 8 patients (16.7%) with ANSD was recorded TEOAE during the initial audiological diagnosis, in contrast to sensorineural hearing loss (TEOAE was not recorded in 100% of patients) (p <0.05). In contrast to sensorineural hearing loss, the ABR thresholds in ANSD did not correspond to the behavioral hearing thresholds. CMP was recorded on the right and left ear in all patients (100%) with ANSD and remained unchanged during the observation process, in contrast to patients with sensorineural hearing loss, in whom CMP was not recorded on both sides (p <0.05). Conclusions. The structure of the main risk factors for hearing loss in children with ANSD and sensorineural hearing loss is different. In the differential diagnosis with sensorineural hearing loss, the possibility of TEOAE disappearance in ANSD should be taken into account. Registration of ABRs with the allocation of CMP is the most informative method of ANSD diagnostics. CMP registration should be conducted for all patients who do not have ABR peaks at the maximum stimulus intensity, regardless of the OAE registration results.