Article Figures & Data
Figures
- Fig 1.
MRA MIP (A) and axial source (B) images demonstrating high-grade stenosis of the right intracranial ICA. For an accurate measurement of the degree of Warfarin-Aspirin Symptomatic Intracranial Disease stenosis, we made a linear measurement of the most stenotic portion of the ICA on either the MIP or axial source image, in this case 0.9 mm (C). A second “normal” measurement was made at the widest, nontortuous, normal portion of the petrous ICA that had margins parallel with the site of stenosis, in this case 5.3 mm (D). If the petrous ICA was also diseased, the most distal, parallel part of the extracranial ICA was measured. The ratio of these 2 measurements was then used to calculate the WASID stenosis, in this case [1 − (0.9/5.30)] × 100 = 83% stenosis. Alternatively, we could use the single linear measurement at the site of greatest stenosis, 0.9 mm (C), which correlates with a stenosis of >70%.
- Fig 2.
Correlation scatterplot demonstrating a linear relationship between millimeter stenosis measurements and percentage WASID stenosis for all included patients with R = −0.84 (P < .0001).
- Fig 3.
A, Receiver operating characteristic curve for predicting >70% stenosis demonstrates an optimal cutoff of 1.3 mm. B, Receiver operating characteristic curve for predicting >50% stenosis demonstrates that a measurement of 2.1 mm is an ideal cutoff.
Tables
Variable No. (%) Age (yr) (mean) 71.9 ± 14.0 Female 91 (47.2) Race White 173 (89.6) Black 11 (5.7) Other 9 (4.7) Atrial fibrillation 27 (14.0) Coronary artery disease 37 (19.2) Carotid artery disease 7 (3.6) Diabetes 55 (28.5) Hypertension 132 (68.4) Dyslipidemia 103 (53.4) NIHSS quartile 1 54 (28.0) 2 48 (24.9) 3 22 (11.4) 4 69 (35.8) Prior stroke 63 (32.6) Peripheral vascular disease 13 (6.7) Active tobacco use 18 (9.3) Stroke subtype Cardioembolic 62 (32.1) Cryptogenic 77 (39.9) Large-artery atherosclerosis 25 (13.0) Small-vessel occlusion 20 (10.4) Other 9 (4.7) IV tPA administered 16 (8.3) Valvular disease 4 (2.1) - Table 2:
WASID percentage stenosis estimates from millimeter measurements of the most stenotic portion of the intracranial ICA
Stenosis (mm) % WASID Stenosis (95% CI) 3.0–3.8 14–30 2.2–2.9 31–48 1.3–2.2 50–65 <1.3 >65 - Table 3:
Breakdown of the millimeter measurements of the 139 arteries with detectable WASID stenosis
Stenosis Measurement <50% 50%–69% 70%+ Total >2.1 mm 75 6 0 81 1.4–2.1 mm 14 32 0 46 ≤1.3 mm 0 6 6 12 Total 89 44 6 139
