Melissa Trotman-Lucas, PhD
Retinal damage is a significant stroke-associated outcome, with 92% of patients suffering visual impairments during the initial recovery phase. Partial, and in some cases complete, recovery can occur; however, 20% of patients will suffer persistent or permanent visual impairment. The anatomic link between the ophthalmic artery and the middle cerebral artery is a potential factor in the reduction of retinal blood flow during middle cerebral artery occlusion (MCAO). The reduced blood flow leads to ischemic retinal damage and subsequent visual impairment. Visual disability is much less evident than other motor or speech deficits following stroke, yet can significantly affect a patient’s rehabilitation, including functional recovery and quality of life. Reduction in rapid eye movements, visual acuity and visual field defects can occur, affecting daily activities and capabilities such as reading, mobility, postural stability, spatial recognition and more. These directly affect a patient’s independence, increasing fear and disorientation, reducing confidence and leading to social withdrawal. Current therapy for stroke-associated visual impairment is neurovisual rehabilitation, involving guiding a patient to learn coping strategies to improve quality of life. Retinal ischemia also shares parallels in pathology to other ocular vascular diseases, such as diabetic retinopathy, glaucoma, retinal vein occlusion and central retinal artery occlusion. There is a need to better understand the similarities and relationship between cerebral ischemia and retinal ischemia, particularly ischemic stroke that incorporates retinal ischemic damage. The lack of current understanding may contribute to the absence of effective treatments for this prevalent post-stroke outcome.