Objective: The assessment of middle ear function by radiological landmarks of the Eustachian tube (ET) region in Down’s syndrome (DS), Otitis Media (OM) and control groups. The Eustachian tube length (ET length), Posterior Upper Facial Height (PUFH), Maxillary Depth (MD), Total Cranial Base (TCB), and S-Ba to ET length and S-Ba to Palatal line were compared in DS, Otitis Media and control groups.The hearing status was classified as Normal, Slight Hearing Loss (HL),Mild HL, Moderate HL, Moderately Severe HL and Severe HL.
Methods: The study comprised of 75 subjects of both sexes in the age range of 7 to 20 years. Digital Lateral Cephalometry was performed for Trisomy 21, OM and controls (n=25). The Eustachian tube function was determined using the Pure Tone Audiometry & Immittence audiometry.
Results: ET length, PUFH, MD and TCB were found to be significantly reduced in the DS, OM and controls. S-Ba to ET length and S-Ba to Palatal line showed a marked reduction in patients with DS, OM and S-Ba to ET and S-Ba to PL and was significantly reduced in patients with B and C tympanograms. There was a strong association between middle ear function and radiological landmarks in the study groups. The acute angle of entry into the nasopharynx and the diminished tube size predispose to risk of Otitis Media. The Distribution of subjects with various hearing status in the three groups was statistically significant in the left as well as the right ears
Conclusion: Aberration in the dimension of the region of the ET can be considered as a predisposing factor for OM in Down’s syndrome. Assessment of ET related parameters in OM and Down’s syndrome is vital in analyzing the alteration in function and implementing preventive measures for decreasing the disability. Early identification and intervention coupled with regular re-evaluation of the audiological parameters before the onset of COM can help reduce the severity of the disability in the vulnerable groups. This is a pioneering study in the multidisciplinary field of radiology and audiology.