Reply: ‘Central retinal artery occlusion and cerebral stroke’

Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy

“…That is to say, both the persisting functional loss and the clinical signs point to retinal infarction, so the Iowa approach is indisputably in breach of terminological convention (Albers et al, 2002;Easton et al, 2009). This matter has proved to be a source of abject confusion, even amongst experts in CRAO and its management, because a "transient" CRAO (as defined in the Iowa CRAO classification) has been wrongly taken to mean an ocular "TIA" and to thus imply full functional recovery after retinal reperfusion Varma et al, 2013;McLeod, 2013;Lee et al, 2013).…”

“…Of note, the "at risk but salvageable" definition of (hypoxic) penumbral tissue applies equally well to anoxic neurons that are reversibly depolarised (albeit only for a very brief period and subject to significant delays in functional recovery on reperfusion). For similar reasons, and adding to the potential confusion, the anoxic tissue compartment developing within the inner retina following CRAO is sometimes considered to be part of the ischaemic penumbra (Hayreh, 1999;Lee et al, 2013).…”

Retinal artery occlusion - Experimental and epidemiological studies

“…Some authors argue that it is most likely markedly prolonged 20 , while others argue that it does not exceed that of the anoxic part, based on the results from clinical research. 26…”