Bilateral inferior hemifield visual loss secondary to a pituitary prolactinoma

Analysis of visual field disturbance in patients with sellar and suprasellar lesions: relationship with magnetic resonance imaging findings and sagittal bending of the optic nerve

PURPOSE

Visual dysfunction due to sellar and suprasellar lesions is thought to be caused by chiasmatic compression and bending of the optic nerve at the entrance of the optic canal. We examined the relationship between visual field impairment and magnetic resonance (MR) imaging.

METHODS

This study reviewed 122 consecutive patients with sellar and suprasellar tumors. We have newly devised a simple visual field impairment score (SVFIS) that was divided into 12 areas. SVFIS is classified into four grades as mild (0-3 points), moderate (4-6 points), severe (7-9 points), and most severe (10-12 points) for each eye. We investigated the relationship between SVFIS grades and MR imaging, including the recently reported optic nerve-canal bending angle (ONCBA) and visual acuity.

RESULTS

Ipsilateral visual acuity tended to deteriorate with increased SVFIS grade. Larger ONCBA was associated with increased SVFIS grades. Bitemporal hemianopia occurred in the early stage (mild case), but the central visual field within 30° was particularly likely to be impaired. The visual field disturbance progressed clockwise (counterclockwise on the left side) from the upper temporal side. Disorders of the central visual field within 5° were associated with ipsilateral large ONCBA.

CONCLUSIONS

The newly developed SVFIS grades are closely associated with indicators of visual pathway impairment on MR imaging, and are useful as indicators of the severity and progression of visual field impairment due to sellar and suprasellar lesions. Disorders of the central visual field within 5° were found to be associated with ipsilateral large ONCBA.