Biomechanical adaptation to post-stroke visual field loss: a systematic review

Area of Science:

• Neuroscience
• Ophthalmology
• Rehabilitation Medicine

Background:

• Homonymous visual field defects are common after stroke, affecting up to 30% of individuals with unilateral brain damage.
• These defects significantly impact daily functioning and quality of life.

Purpose of the Study:

• To systematically review and synthesize evidence on biomechanical changes in visual field loss following stroke.
• To understand alterations in eye, head, and body movements during visual exploration in individuals with hemianopia.

Main Methods:

• A systematic review of randomized controlled trials, cohort studies, before-after studies, and case-controlled studies.
• Inclusion of studies investigating eye, head, or body movements in post-stroke visual field loss.
• Independent selection and data extraction by two authors, with risk of bias assessment.

Main Results:

• Thirty-six articles involving 1123 participants were analyzed.
• Individuals with hemianopia and simulated visual field loss showed altered fixation and saccade parameters compared to controls.
• Gaze behavior in true hemianopia was biased towards the blind hemifield, unlike simulated hemianopia.

Conclusions:

• Significant evidence exists for altered eye movements in hemianopia, with compensatory mechanisms observed.
• Successful visual exploration involves increased saccade amplitude, velocity, and a shift into the blind field.
• There is a notable lack of research on head and body movement parameters in hemianopia, necessitating further investigation.