The effect of moderate exercise on retinal and optic nerve head blood flow as measured by the Heidelberg Retina Flowmeter

Purpose. The effect of moderate dynamic exercise on capillary blood flow parameters in the retina and optic nerve head (ONH) was evaluated using noninvasive Scanning Laser Doppler Flowmetry (Heidelberg Retina Flowmeter, HRF). Methods. Twenty young, healthy non-smoking volunteers were enrolled in the study. Five HRF measurements were taken before and two further measurements were completed immediately after exercise. All measurements were performed on right eyes. Blood pressure and pulse rate were obtained before and after exercise. Exercise required at least a 30% increase in pulse rate over baseline. HRF parameters volume, flow and velocity were recorded in the following four areas: nasal retina, within one disc diameter from ONH; temporal retina, within one disc diameter from ONH; nasal ONH rim; temporal ONH rim. Results. Pulse rate averaged 67 ± 9 before and 104 ± 14 (p < 0.05) after exercise. Paired, two-tailed t test yielded p values >0.092 for all measured HRF parameters in all four locations after exercise, showing no significant change. Conclusions. These results appear to indicate that in healthy young subjects autoregulation of blood flow in the ONH and retinal capillaries is effective after moderate exercise.