Assessment of the cochlear nerve to facial nerve size ratio using MR multiplanar reconstruction of the internal auditory canal in patients presenting with acquired long-standing hearing loss

• Published in: British journal of radiology Vol. 90; no. 1073; p. 20160870
• Main Authors: Naguib, Nagy N N, Hey, Constanze, Shaaban, Mohamed S, Elabd, Amr M, Hassan, Hebatallah H M, Gruber-Rouh, Tatjana, Kaltenbach, Benjamin, Harth, Marc, Ackermann, Hanns, Stöver, Timo, Vogl, Thomas J, Nour-Eldin, Nour-Eldin A
• Format: Journal Article
• Language: English
• Published: England The British Institute of Radiology 01-05-2017
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Cochlear Nerve - diagnostic imaging; Ear, Inner - diagnostic imaging; Facial Nerve - diagnostic imaging; Female; Head and Neck; Hearing Loss, Sensorineural - diagnostic imaging; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging - methods; Male; Middle Aged; Retrospective Studies; Temporal Bone - diagnostic imaging; Time Factors; Young Adult
• ISSN: 0007-1285; 1748-880X
• DOI: 10.1259/bjr.20160870

To test using the facial nerve as a reference for assessment of the cochlear nerve size in patients with acquired long-standing sensorineural hearing loss (SNHL) using MRI multiplanar reconstruction.
The study was retrospectively performed on 86 patients. Group 1 (study group, n = 53) with bilateral long-standing SNHL. Group 2 (control group, n = 33) without hearing loss. The nerve size was measured by drawing a region of interest around the cross-sectional circumference of the nerve in multiplanar reconstruction images.
No significant correlation was noted between the cochlear nerve and facial nerve size, and the patient's age, gender and weight (p > 0.05). In Group 1, the mean ratio of the cochlear to facial nerve size was 0.99 ± 0.30 (range: 0.52-1.86) and 1.12 ± 0.35 (range: 0.34-2.3) for the right and left sides, respectively. In Group 2, it was 1.18 ± 0.23 (range: 0.78-1.71) and 1.25 ± 0.25 (range: 0.85-1.94) for the right and left sides, respectively. The cochlear nerve size was statistically (p = 0.0004) smaller in Group 1 than in Group 2.
The cochlear nerve size and the cochlear to facial nerve size ratio are significantly smaller in patients with acquired long-standing SNHL. Advances in knowledge: The facial nerve can be used as a reference for assessment of the cochlear nerve in patients with acquired long-standing SNHL.