The International Tinnitus Journal

Middle Ear Disease, Eustachian Tube Dysfunction and Hearing Outcomes in Children with Cleft Palate Living in Different Environmental Zones of the Aral Sea Region: A Comparative Observational Study

Nigora E. Makhkamova, Olimjon K. Baltabaev, Aziza G. Madrimova

Objective: Children with cleft palate are predisposed to Eustachian tube dysfunction (ETD), middle ear effusion and conductive hearing loss because of the abnormal orientation and impaired activity of the soft palate musculature. The Aral Sea region is exposed to airborne mineral dust and saline aerosols that may irritate the upper respiratory mucosa. This study characterised middle ear disease, ETD and hearing impairment in children with cleft palate living in different environmental zones of the Aral Sea region, and evaluated hearing outcomes after staged otorhinolaryngological and audiological management. Materials and Methods: A comparative observational study included 150 children with cleft palate aged 2 months to 18 years. The regional exposure group comprised 120 children resident in the Muynak, Kungrad, Takhtakupyr and Chimbay districts of the critical coastal zone; the comparison group comprised 30 children from Urgench, an area with a lower background dust and salt aerosol burden. Assessment included history, otorhinolaryngological examination, otomicroscopy, nasal and nasopharyngeal endoscopy, pure-tone or play audiometry, age-appropriate objective hearing assessment, tympanometry, acoustic reflex testing, evaluation of Eustachian tube patency, and magnetic resonance imaging (MRI) of the velopharyngeal region where clinically indicated. Outcomes were assessed at successive stages of palatal surgery and hearing rehabilitation. Results: Otorhinolaryngological abnormalities were present in 98.2-100% of children from the critical coastal zone. Otitis media with effusion (OME) accounted for 57% of middle ear disease, adhesive otitis media for 29% and chronic suppurative otitis media (CSOM) for 14%. Endoscopy of the pharyngeal orifice of the Eustachian tube showed mucosal atrophy or thinning in 44%, torus tubarius hypertrophy in 30.1%, lymphoid hyperplasia in 17.3% and cicatricial change in 8.6%. In the youngest clinical group, parents reported hearing difficulty in 24% of children, whereas objective audiological testing detected hearing loss in 37% and otomicroscopy identified abnormalities in 89%. After comprehensive treatment, hearing thresholds improved by 20-30 dB in 92% of these children. In the early postoperative subgroup all children with impaired hearing improved by 10-20 dB and pure-tone thresholds normalised at one year, although type B or C tympanograms persisted in 50%. Recovery of Eustachian tube function was more favourable after palatal repair before 3 years of age. MRI showed a mean residual velopharyngeal closure gap of 8.35 +/- 0.43 mm, with signs of soft palate muscle atrophy in 41.6% of those imaged. Conclusion: Children with cleft palate living in the critical coastal zone of the Aral Sea region showed a high prevalence of combined nasopharyngeal, Eustachian tube, middle ear and hearing disorders. Objective hearing assessment identified abnormalities far more often than parental observation. Early palatal repair, scheduled otorhinolaryngological and audiological surveillance, treatment of upper airway and middle ear inflammation, and individualised use of ventilation tubes were associated with improved hearing outcomes. Because environmental exposure was assigned at area level rather than by individual particulate monitoring, the regional differences observed should be interpreted as associations and require confirmation in prospective exposure-based studies. Trial registration: Not applicable. This was a non-interventional observational study of routine clinical care and was not registered in a WHO/ICMJE clinical trial registry.