Mediterr. J. Otol 2008; 4:(2)

Clinical Significance of Vestibular Aqueduct's width in Pediatric Patients with Sensorineural Hearing Loss

Eshrak Hassanein, Maha A. Ghaffar, Mohamed Taha, Hesham Taha

Department Otorhinolaryngology, Ain- Shams University Hospital, Faculty of Medicine, Cairo, Egypt.  mys961@hotmail.com 

Objective: To assess the clinical significance of vestibular aqueduct (VA) width measurement on high resolution CT images in pediatric patients with sensorineural hearing loss (SNHL).

Materials and Methods: 34 pediatric patients with sensorineural hearing loss (Group I) and 42 controls without SNHL (Group II) underwent otorhinolaryngological, otoneurological examinations, full audiological, sinusoidal harmonic acceleration evaluation and high resolution CT scan of temporal bone. VA width was measured at coronal and axial planes (at both midpoint and opercular levels). 

Results:  In control group, vestibular aqueduct mean width was [0.80 and 0.71] at right and left midpoint, [1.6 mm] at opercular level and (1.4 mm at right and 1.5 at left side) on coronal image. Enlarged vestibular aqueduct was in nineteen (55.9%) patients with SNHL. VA mean width was [2.62 and 2.35] at midpoint, [3.31 and 3.27 mm] at opercular level, and (2.8 mm and 3.24) on coronal images at right and left sides respectively.

Sinusoidal Harmonic Acceleration (SHA) was abnormal in (47%) of children with SNHL; (68.8%) of them had enlarged VA.

Conclusion: VA is enlarged; if it exceeded (1.2), (2.1) and (1.5) mm at midpoint, opercular level and on coronal images respectively. Incidence of enlarged vestibular aqueduct is higher with severe to profound hearing loss. Incidence of gain abnormality in rotational testing is common in patients with enlarged vestibular aqueduct. Most children with enlarged vestibular aqueduct have combined audio-vestibular dysfunction.