Silicone Oil in Optic Chiasm: Case Report and Review of the Literature

Abstract

Purpose:

To report a case of silicone oil migration into optic chiasm with resultant visual field defect in the fellow eye. We also summarize the risk factors and pathogenic mechanisms responsible for the silicone oil migration and the subsequent neurological effects associated with it.

Methods:

A 36-year-old gentleman presented with a history of vitrectomy with silicone oil tamponade in the left eye with sudden-onset temporal field defect in the right eye. Silicone oil was identified in left optic nerve and left half of optic chiasm. Intrachiasmatic and intraneural silicone oil was removed by left pterional craniotomy.

Result:

Prompt visual field recovery in the right eye after the neurosurgical intervention was noted.

Conclusion:

Intracranial migration of silicone oil is rare, with only a handful of cases reported in the literature. Intrachiasmal and intraneural silicone oil is associated with loss of nerve fibers and resultant vision and visual field loss. Prompt neurosurgical intervention results in the improvement of visual field defects. So early identification and neurosurgical intervention is warranted. Vitreoretinal surgeons should be aware of transneural migration of silicone oil, and a high degree of suspicion is warranted when patient develops visual symptoms in the fellow eye, particularly in cases with glaucomatous optic neuropathy and secondary elevated intraocular pressure or in any disc malformation.