Table 2.

Arterial characteristics by arterial segment.

Arterial segments	Interadventitial diameter (mm ± SD)*	Lumen diameter (mm ± SD)*	Media thickness (μm ± SD)*	Media proportion of the wall (%)	Adventitia thickness (μm ± SD)*	Wall thickness (μm ± SD)*	Luminal stenosis(% ± SD)*	Wall-to- lumen ratio (± SD)*
Proximal ICA (supraclinoid) (N = 70)	3.9±0.9	2.9±0.8	200.8±68.9	40.2±9.7	159.8±60.2	529.8±232.1	19.9±14.9	6.2±2.5
Distal ICA (supraclinoid) (N = 238)	3.8±0.8	2.9±0.7	189.8±52.8	43.4±8.9	140.6±36.5	451.5±141.2	15.1±10.4	7.0±2.6
Proximal M1 MCA (N = 291)	3.1±0.7	2.3±0.6	149.5±42.7	41.1±9.1	134.4±33.7	383.6±131.8	15.4±10.8	6.6±2.2
Distal M1 MCA (N = 296)	2.9±0.6	2.2±0.5	141.2±37.1	41.2±8.2	124.2±32.6	357.4±131.8	14.5±9.5	6.5±2.0
Proximal M2 MCA (N = 264)	2.4±0.6	1.8±0.5	125.6±36.2	41.5±8.1	116.8±31.9	311.9±102.1	14.5±10.3	5.9±1.8
Proximal A1 ACA (N = 252)	2.4±0.6	1.7±0.5	133.4±43.9	42.9±8.4	112.5±30.4	318.7±106.2	15.8±11.8	5.8±2.1
Distal A1 ACA (N = 152)	2.3±0.5	1.7±0.4	124.5±47.2	43.0±8.8	106.6±26.0	296.4±97.9	13.1±7.7	6.2±2.1
Proximal V4 VA (N = 148)	3.2±1.2	2.3±0.9	152.0±50.9	38.4±9.9	160.2±83.0	431.3±212.9	17.8±13.1	6.1±2.5
Distal V4 VA (N = 220)	2.9±0.9	2.2±0.8	148.3±49.1	42.0±9.6	113.2±37.7	368.7±136.2	17.8±12.4	6.3±2.2
Proximal BA (N = 167)	3.7±1.0	2.9±0.8	165.5±51.9	43.7±11.0	117.0±32.7	407.0±175.8	14.7±12.3	7.8±2.9
Distal BA (N = 122)	3.4±0.9	2.6±0.6	165.5±52.6	45.9±9.1	109.0±32.7	377.9±145.6	13.8±10.7	7.6±2.7
Proximal P1 PCA (N = 43)	2.5±0.6	1.8±0.6	160.9±49.4	47.3±10.4	94.5±20.6	353.9±102.9	20.4±15.3	5.5±2.3
Distal P1 PCA (N = 16)	2.6±0.4	1.7±0.4	136.0±39.3	36.0±16.4	100.0±27.3	442.3±184.9	34.6±23.7	4.6±2.5

Abbreviations: mm, millimeters; um, micrometers; ICA, internal carotid artery; MCA, middle cerebral artery; ACA, anterior cerebral artery; BA, basilar artery; VA, vertebral artery; PCA, posterior cerebral artery; N, number.

^*ANOVA test resulted in P ≤ 0.001 for all comparisons.