Table 3.

Number of outcomes and Kaplan–Meier curve–based risk of the outcome among near-occlusions at different time intervals after presenting event. Different definitions of full collapse are presented. Conventional ≥ 50% stenosis group presented for general comparison. The outcome was preoperative recurrent ipsilateral ischemic stroke or ipsilateral retinal artery occlusion

Definition of full collapse	Full collapse	Cases (% of near-occlusions)	2 days		7 days		14 days		28 days		pa
			n	% Risk (95%CI)	n	% Risk (95%CI)	n	% Risk (95%CI)	n	% Risk (95%CI)
Traditional, by appearance	No	69 (59)	4	6 (0–11)	6	9 (2–15)	7	11 (3–18)	7	11 (3–18)	0.047
	Yes	47 (41)	8	17 (6–28)	9	19 (8–30)	10	21 (10–33)	12	27 (14–39)
Distal ICA diameter ≤ 2.4 mm	No	58 (50)	1	2 (0–5)	2	4 (0–8)	2	4 (0–8)	2	4 (0–8)	< 0.001
	Yes	58 (50)	11	19 (9–29)	13	22 (12–33)	15	26 (15–38)	17	31 (18–43)
Distal ICA diameter ≤ 2.0 mm	No	71 (61)	3	4 (0–9)	4	6 (0–11)	4	6 (0–11)	4	6 (0–11)	< 0.001
	Yes	45 (39)	9	20 (8–32)	11	24 (12–37)	13	29 (16–43)	15	34 (20–48)
ICA ratio ≤ 0.47	No	68 (61)	2	3 (0–7)	4	6 (0–12)	4	6 (0–12)	4	6 (0–12)	< 0.001
	Yes	44 (39)	10	23 (10–35)	11	25 (12–38)	13	30 (16–43)	15	35 (21–50)
ECA ratio ≤ 0.96	No	43 (37)	2	5 (0–11)	4	10 (1–18)	4	10 (1–18)	4	10 (1–18)	< 0.001
	Yes	73 (63)	10	14 (6–22)	11	15 (7–23)	13	18 (9–27)	15	22 (12–32)
Distal ICA diameter ≤ 2.0 mm and/or ICA ratio ≤ 0.42	No	70 (60)	2	3 (0–7)	3	4 (0–9)	3	4 (0–9)	3	4 (0–9)	< 0.001
	Yes	46 (40)	10	22 (10–34)	12	26 (13–39)	14	31 (17–44)	16	36 (22–50)
Conventional ≥ 50% stenosis		315 (NA)	9	3 (1–5)	16	5 (3–8)	25	10 (6–13)	27	11 (7–15)	NA

95%CI 95% confidence interval, ECA external carotid artery, ICA internal carotid artery, NA not applicable

^aLog rank test between the two near-occlusion groups, i.e., conventional ≥ 50% stenosis group not included in these calculations