Table 4.

Longitudinal changes in retinal capillary blood flow from baseline to four-year follow-up in OAG patients of African and European descent.

HRF	Retinal Area	Race	Baseline Mean (n)	4-year Mean (n)	Mean change from baseline to follow-up	p-value	Comparison of change between races (p-value)
Zero Pixel Blood Flow*	Superior Retina	AD	0.193 (29)	0.214 (19)	0.019	0.214	0.856
		ED	0.199 (83)	0.224 (61)	0.023	0.012
	Inferior Retina	AD	0.172 (28)	0.228 (20)	0.042	0.001	0.034
		ED	0.189 (83)	0.204 (59)	0.013	0.143
Mean Blood Flow**	Superior Retina	AD	449.79 (29)	458.15 (19)	8.21	0.815	0.460
		ED	411.45 (83)	392.08 (61)	−20.33	0.285
	Inferior Retina	AD	487.46 (28)	430.44 (20)	−64.57	0.092	0.429
		ED	397.34 (83)	374.95 (59)	−23.73	0.176

Bold P-values indicate statistical significance (p<0.05).

Note: At four-year follow-up, the superior retinal HRF recording was unable to be obtained in one AD patient due to poor image quality. Also two patients of ED were unable to be assessed for HRF inferior retinal flow due to poor image quality.

Table 4 legend: AD-African descent; ED-European descent; HRF-Heidelberg Retinal Flowmetry; n-number of participants; OAG-open angle glaucoma.

^*Zero pixel blood flow represents the % (shown as a decimal) avascular area of the total peripapillary retinal area measured with no detectable blood flow.

^**Mean blood flow represents the average recorded retinal capillary blood flow in the respective peripapillary superior and inferior retina.