Cochlear Nerve Dimensions in Asymetrical Sensorineural Hearing Loss: A Morphometric Study/Asimetrik Sensorinoral Isitme Kaybinda Koklear Sinir Boyutlari: Morfometrik Calisma

• Published in: Istanbul medical journal 2021-05, Vol.22 (2), p.115
• Main Authors: Yigider, Ayse Pelin, Yildiz, Omer, Kufeciler, Levent, Kocak, Hasan Emre, Acipayam, Harun, Kayhan, Fatma Tulin, Inci, Ercan
• Format: Article
• Language: eng ; tur
• Subjects: Deafness; Hearing loss; Investigations; Medical research; Medicine, Experimental
• ISSN: 2619-9793; 1304-8503
• DOI: 10.4274/imj.galenos.2021.08941

Introduction: To investigate the relationship between morphometric variants of the cochlear nerve (CN) and the hearing level. To investigate the confounding effects of age, sex, and audiometric variables on the relationship between CN morphometrics and hearing loss, if present. Methods: Audiological data and magnetic resonance imaging findings of 127 patients with asymmetrical sensorineural hearing loss (ASNHL) were reviewed retrospectively. According to pure tone average (PTA) frequencies of each ear, difference above 25 dB were accepted as ASNHL. The vertical (Vd) and horizontal diameters (Hd) and the cross-sectional area (CSA) of the CN were measured. Results: The difference in CSA and Vd between ears showed a negative correlation with age. The mean CSA was 1.57 in AE and 1.60 in NE. Mean Hd was 1.00 in AE and 1.00 NE. Mean Vd was 1.40 in AE and 1.50 in NE. There was no correlation between the difference ratios of thresholds and CN diameter parameters. There was no significant correlation of CSA, Vd, and Hd with PTA thresholds at each frequency. Conclusion: Aging is associated with losses in Vd diameter and CSA. The degree of hearing loss was not correlated with the morphometric features of the CN. The morphometry of the CN should be interpreted together with the etiology of hearing loss. Keywords: Hearing loss, unilateral, deafness, ear, inner, cochlear nerve Amac: Koklear sinirin morfometrik ozellikleri ile isitme seviyesi arasinda iliski varligini arastirmaktir. Yas, cinsiyet ve odyometrik ozelliklerin, koklear sinir morfometrisi ve isitme kaybi iliskisine etkisi olup olmadigini arastirmaktir. Yontemler: Asimetrik sensorinoral isitme kaybi (ASNIK) nedeniyle basvuran 127 olgunun odyolojik verileri ve manyetik rezonans goruntuleme bulgulari retrospektif olarak tarandi. Saf ses ortalamasina gore kulaklar arasinda 25 dB ve uzeri fark olmasi ASNIK olarak kabul edildi. Koklear sinirin vertikal capi (Vd), horizontal capi (Hd) ve kesitsel alani (CSA) olculdu. Bulgular: Kesit yuzey alani ve Vd yas ile negatif korelasyon gosterdi. Ortalama CSA etkilenen kulaklarda 1,57 iken etkilenmeyen kulaklarda 1,60 idi. Ortalama Hd'yi etkilenen ve etkilenmeyen kulakta ayni idi. Ortalama Vd etkilenen kulakta 1,40 etkilenmeyen kulakta 1,50 idi. Isitme esiklerindeki degisim oranlari ile koklear sinir caplari arasinda iliski gozlenmemistir. CSA, Vd, Hd ile saf ses ortalamasi arasinda iliski gozlenmemistir. Sonuc: Yaslanma ile sinir Vd'den kaybeder ve toplam CSA azalir. Isitme