Table 1.

Experimentally observed values of vessel diameter and flow rate in different parts of the murine and human adult retina as reported in various publications. BTBR and C57BL/6J are two common mouse strains used as models of human disease. Values given as mean ± s.e. of the mean, when possible. The values reported by Zhi et al. [22] are measured at five different arteries/veins and averaged over three independent measurements. Significant inconsistencies are found across the surveyed literature: (a) Wright et al. [23] and Wang et al. [21] measured flow rates approximately one order of magnitude higher than Zhi et al. [22] and (b) the arterial diameter measured in Ninomiya & Inomata [14] is substantially lower than in Wright et al. [23].

authors	species	measurement	value
Wright et al. [23]	30-week-old C57BL/6J male mice	arterial diameter	∼57 μm
		venous diameter	∼62 μm
		mean arterial velocity	∼25 mm s−1
		mean venous velocity	∼24 mm s−1
		arterial flow rate	∼3.9 μl min−1
		venous flow rate	∼4.8 μl min−1
Zhi et al. [22]	22-week-old BTBR female mice	arterial flow rate	(0.40 ± 0.04) μl min−1
			(0.55 ± 0.06) μl min−1
			(0.50 ± 0.05) μl min−1
			(0.48 ± 0.05) μl min−1
			(0.40 ± 0.04) μl min−1
			(0.45 ± 0.06) μl min−1
		venous flow rate	(0.45±0.04) μl min−1
			(0.62 ± 0.06) μl min−1
			(0.60 ± 0.04) μl min−1
			(0.59 ± 0.05) μl min−1
			(0.38 ± 0.03) μl min−1
			(0.63 ± 0.06) μl min−1
Wright et al. [24]	11–12-week-old C57BL/6 male mice	arterial diameter	(60.4 ± 0.7) μm
		venous diameter	(69.3 ± 1.3) μm
		mean arterial velocity	(28.3 ± 1.4) mm s−1
		mean venous velocity	(26.3 ± 1.2) mm s−1
Ninomiya & Inomata [14]	4-month-old mice (ex vivo)	arterial diameter	up to 28 μm
		capillary diameter	5 μm to 6 μm
Wang et al. [21]	adult human	arterial diameter	(91.23 ± 11.80) μm
		arterial peak velocity	(24.15 ± 1.50) mm s−1
		arterial flow rate	(6.83 ± 1.75) μl min−1
		venous diameter	(69.83 ± 3.52) μm
		venous peak velocity	(46.43 ± 1.42) mm s−1
		venous flow rate	(6.42 ± 0.72) μl min−1