Article Figures & Data
Figures
- FIGURE.
Illustrative case showing covert SS. A patient in her 60s presented with aphasia and right-sided weakness. A, A left ICA lateral angiogram shows occlusion of distal M2 segment (arrow). B, After 3 attempts of thrombectomy using a Trevo 3 × 20 mm (not shown), successful reperfusion was achieved. Note that vasospasm is revealed (arrowheads) without definite contrast extravasation. M2 angulation is measured as 130° on the final angiogram. C, A noncontrast CT scan obtained 1 day after thrombectomy shows a small amount of hyperdense lesions (arrow) in the left Sylvian fissure. D, Axial GRE MR imaging performed 3 days after thrombectomy reveals an apparent hypointense signal lesion in the left Sylvian fissure (arrow), consistent with SAH.
Tables
Total (n = 209) Sulcal SAH (n = 33) Non-Sulcal SAH (n = 176) P Value Age (mean) (yr) 69.9 (SD, 12.4) 73.1 (SD, 11.2) 69.3 (SD, 12.6) .104 Male 110 (56.9) 16 (48.5) 103 (58.5) .38 Risk factor Hypertension 139 (66.5) 21 (63.6) 118 (67.0) .857 Diabetes 71 (34.0) 13 (39.4) 58 (33.0) .606 Dyslipidemia 53 (25.4) 11 (33.3) 42 (23.9) .353 Smoking 43 (20.6) 10 (30.3) 33 (18.8) .203 Coronary artery disease 21 (10.0) 3 (9.1) 18 (10.2) 1.0 Atrial fibrillation 97 (46.4) 13 (39.4) 84 (47.7) .49 Previous stroke 30 (14.4) 4 (12.1) 26 (14.8) .898 Etiology of occlusion Thromboembolic 180 (86.1) 29 (87.9) 151 (85.8) .999 In-situ thrombosis 27 (12.9) 3 (9.1) 24 (13.6) .583 Intravenous tPA 44 (21.1) 6 (18.2) 38 (21.6) .835 Prestroke mRS 0 (0–1) 0 (0–0) 0 (0–1) .85 Admission NIHSSb 10 (7–15) 11 (7–15) 10 (7–15) .953 ASPECTSb 9 (8–10) 9 (8–9) 9 (8–10) .764 Occlusion site <.001 Proximal 146 (69.9) 10 (30.3) 136 (77.3) Distal 63 (30.1) 23 (69.7) 40 (22.7) Division .064 Superior 98 (46.9) 21 (63.6) 77 (43.8) Inferior 106 (50.7) 11 (33.3) 95 (54.0) Middle 5 (2.4) 1 (3.0) 4 (2.3) Characteristics Sulcal SAH (n = 33) Overt SAH (with Intraprocedural Contrast Extravasation)(n = 10) (30.3%) Covert SAH (without Intraprocedural Contrast Extravasation)(n = 23) (69.7%) Management Coil embolization 7 (70.0) Observation 3 (30.0) Imaging findings SAH detected solely by serial CT 5 (50.0) 2 (8.7) SAH detected by GRE/FLAIR 5 (50.0) 21 (91.3) Location of SAH Only Sylvian fissure 0 (0) 14 (60.9) Sylvian fissure + 1 sulcus 0 (0) 9 (39.1) Sylvian fissure + ≥2 sulci 5 (50.0) 0 (0) Diffuse, bilateral 5 (50.0) 0 (0) Clinical outcomes Neurologic deterioration 4 (40.0) 1 (4.3) mRS at 90 daysb 4 (4–5) 2 (1–5) mRS 0–2 at 90 days 3 (30.0) 12 (52.2) Mortality at 90 days 1 (10.0) 3 (13.0) a Data are presented as number (%) except where otherwise noted.
↵b Data are median, and numbers in parentheses are interquartile range.
Variable Crude OR (95% CI) P Value Adjusted OR (95% CI) P Value Age 1.02 (0.99–1.06) .105 Female 1.49 (0.70–3.18) .287 Hypertension 0.86 (0.40–1.91) .704 History of stroke 0.79 (0.22–2.23) .691 Prestroke mRS 0.88 (0.58–1.22) .749 Admission NIHSS 1.01 (0.92–1.09) .854 Baseline ASPECTS 0.96 (0.71–1.31) .805 Procedural time (min) 1.02 (1.01–1.03) <.001 Distal (vs proximal) 7.82 (3.52–18.50) <.001 12.04 (4.56–35.67) <.001 Superior division 2.25 (1.06–4.99) .039 3.83 (1.43–11.26) .010 SR use (vs aspiration) 1.56 (0.67–4.09) .332 M2 angulationa 1.02 (1.01–1.03) <.001 1.02 (1.01–1.04) <.001 No. of passes 1.51 (1.22–1.89) <.001 1.58 (1.22–2.09) <.001 ↵a Continuous variable. Higher M2 angulation indicates greater vessel curvature.
