Retinal complications of gas myelography.

Bilateral retinal and preretinal hemorrhages with an acute and permanent partial loss of visual acuity developed in a 60-year-old man after an oxygen myelogram. In order to increase the contrast of the myelogram, a greater volume of oxygen was injected in the subarachnoid space than the volume of CSF that was removed. It is believed that the hemorrhages and visual loss were secondary to the sudden increase in CSF pressure caused by the excess volume of oxygen injected.