TABLE 1.

Summary Statistics for Reconstructions¹

Recon	EVF	Sheet EVF	Tunnel EVF	Overall median ECW (nm)	Sheet median ECW (nm)	Tunnel median ECW (nm)
A	—	—	—	—	17.32	18.34
B	0.080	0.63	0.37	8.93	7.92	18.43
C	0.201	0.67	0.33	38.25	37.65	41.34
D	0.199	0.66	0.34	33.27	32.26	36.75
E	0.207	0.37	0.63	31.25	22.06	71.59
F	0.203	0.50	0.50	34.55	26.75	46.89
G	0.200	0.23	0.77	30.29	9.52	83.03
H	0.202	0.29	0.71	40.40	15.54	59.00

Recon	Total Area (μm2)	Sheet Area (μm2)	Tunnel area (μm2)	Geometric tortuosity	Diffusivity in ECS (μm2/ms)
A	—	—	—	—	—
B	2,343.62	1,843.46	485.46	1.42 ± 0.04	0.60 ± 0.04
C	2,575.47	1,868.90	704.49	1.22 ± 0.06	0.44 ± 0.05
D	1,940.06	1,389.01	549.57	1.22 ± 0.04	0.44 ± 0.03
E	2,494.80	1,459.41	1033.50	1.28 ± 0.06	0.49 ± 0.05
F	1,834.73	1,168.28	664.57	1.25 ± 0.04	0.47 ± 0.03
G	2,533.01	1,440.60	1090.81	1.41 ± 0.06	0.59 ± 0.05
H	1,866.52	1,042.14	823.09	1.33 ± 0.04	0.53 ± 0.03

¹Recon refers to reconstruction labels in Figure 2. ECW is the median width of the extracellular space (ECS) measured from each surface at a density equivalent to tiling the surface with equilateral triangles of side length 40 nm and then measuring the extracellular width from the barycenter of each triangle. Raw reconstruction has a total volume of 1.83347e+11 nm³. Nonscaled (f = 1) reconstruction has a total volume of 1.82012e+11 nm³. Scaled (f = 1.15) reconstruction total volume was assumed to be 50% more than the nonscaled volume. The square root of the ratio of total surface area of the scaled to nonscaled reconstruction should equal the scaling factor f. Given mean surface areas of 2,534.4 and 1,880.4 μm² for scaled and nonscaled reconstruction respectively, the calculated scaling factor is 1.16, close to the 1.15 used, suggesting that total surface area is insensitive to reconstruction lacunarity.

EVF, extracellular volume fraction.