Ipsilesional visual field dependency for patients with vestibular schwannoma.

Vestibular schwannoma patients have a non-homogenous vestibular function and compensation, and might rely more on visual cues for balance control. Using the rod and frame test, visual field dependence was investigated in 17 patients with vestibular schwannoma who had a normal subjective visual horizontal and vertical (0.8 +/- 1.4 degrees). Findings were correlated with tumor size, age, and other parameters of vestibular compensation and compared with field dependency results of 28 healthy subjects. Vestibular schwannoma patients showed greater deviation in the rod and frame test when the frame was tilted towards the lesioned ear (mean 8.2 +/- 4.9 degrees), than towards the healthy ear (mean 5.5 +/- 6.0 degrees; p=0.013). The results indicate a unilateral visual field dependency for patients with vestibular schwannoma that predicts the lesioned side.