Retinal haemorrhage as a complication of gas encephalography and gas myelography. Prospective study using oxgen gas with a discussion of pathogenetic mechanisms.

Seventy patients, submitted to oxygen encephalography and oxygen myelography, were examined by retinal funduscopy to establish the incidence of intraocular haemorrhages, a complication reported to be frequent by other investigators. We did not discover any retinal haemorrhages. Pathogenetic factors influencing intracranial or intraocular venous pressure or both are discussed, particularly the effect due to different technical procedures during the examination, and the type of anaesthesia used.