OCTA Signal Quality Augmentation Using the Isometric Handgrip Test to Maximize Vascular Flow (SQUEEZE): A Randomized...

Area of Science:

• Ophthalmology
• Medical Imaging
• Cardiovascular Physiology

Background:

• Macular abnormalities can affect retinal vascularity.
• Optical coherence tomography angiography (OCTA) is crucial for visualizing retinal vasculature.
• Improving OCTA signal quality is essential for accurate diagnosis.

Purpose of the Study:

• To investigate if the isometric handgrip test (IHGT) can enhance OCTA vascular signal quality in eyes with macular abnormalities.

Main Methods:

• A randomized, single-blinded crossover trial involving 36 participants with macular abnormalities.
• Participants underwent OCTA with and without IHGT (50% maximum grip strength for 1 minute).
• Primary outcome: OCTA signal quality; Secondary outcomes: vascular flow measures and blood pressure changes.

Main Results:

• The IHGT did not significantly improve overall OCTA signal quality (P = 0.73).
• Nested analyses revealed increased OCTA B-scan retinal vascular flow (P < 0.05) and elevated blood pressure (P < 0.05) with IHGT.
• OCTA signal quality was associated with sex, refraction, race/ethnicity, and right-hand IHGT use.

Conclusions:

• The IHGT can temporarily increase OCTA B-scan retinal vascular flow in patients with macular abnormalities.
• IHGT-induced blood pressure changes correlate with absolute grip strength, suggesting potential ineffectiveness with low grip strength.
• Further research in larger cohorts is recommended to validate these findings.