Brief Answer:
Sudden MONOCULAR visual loss

Detailed Answer:
Good evening and thank you for your question. I am very sorry this happened to your wife. My suggestion is that you immediately take her to an ER to be evaluated since this more often times than not needs to be evaluated by a specialist and treated in order to best guarantee return of vision as soon as possible.

There are a number of potential causes but the presence of PAIN in the affected eye prior to the visual loss suggests the possibility of an OPTIC NEURITIS or swelling of the optic nerve that completely cut vision off in a very spontaneous manner. She could also have what is referred to as an OPTIC NEUROPATHY due to severe loss of blood flow which would then be called an ATERITIC ISCHEMIC OPTIC NEUROPATHY. If the cause of the visual loss is due to a COMPRESSIVE lesion upon the optic nerve then, though it may be reported as SUDDEN visual loss in point of fact, it more likely to have occurred very slowly and almost unbeknownst to the patient until a critical threshold is reached below which there is a noticeable reduction in visual perception which patients report as sudden and complete visual loss.

Another cause of painful loss of vision in one eye is GIANT CELL ARTERITIS although it is much less likely that the loss of vision is abruptly sudden. Most patients will complain of a noticeable reduction in vision but there is typically time before visual loss turns out to be complete. The danger with this type of visual loss in one eye is that often, without treatment in a timely fashion, there can be affectation of the fellow eye in a large percentage of cases. Therefore, rapid and definitive workup is necessary in order to protect vision in the good eye.

Retinal disease and/or DETACHMENT that you refer is less likely the cause of this visual loss due to the presence of pain. Retinal detachment and other diseases leading to spontaneous and total visual loss in the eye usually occurs in a PAINLESS manner. For the same reason of there being PAIN in the affected eye BRAIN STROKE is highly unlikely. Also, in a brain stroke visual losses and field defects are both reported as well as detectable on examination in BOTH eye fields (right and left). There is a condition of STROKE that occurs within the retina itself, however, again visual loss in these cases is PAINLESS and often times vision will return after a few moments or at least not remain COMPLETE.

Therefore, I hope your wife can be seen quickly if not immediately to assess this dramatic event which if not identified for cause and treated can result in permanent and full visual loss.

Once again, many thanks for the opportunity to answer your questions. I hope your wife's outcomes are healthy and expedited! If I've provided useful information could you do me the favor of CLOSING THIS QUERY with a 5 STAR rating and positive feedback?

Time spent on assessing and researching patient's question and synthesizing a response was 52 minutes.

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