Article Figures & Data
Figures
- Fig 1.
Comparison of the 2 CTA protocols for detecting an aneurysm in the posterior communicating artery. A and B, An 80-kVp cerebral CTA with 30 mL of contrast agent in a 49-year-old woman. A volume-rendered digital subtraction CTA image (A) shows an aneurysm in the left posterior communicating artery (red arrow), which is confirmed by 3D-DSA (B). C and D, A 120-kVp cerebral CTA with 60 mL of contrast agent in a 66-year-old woman. C, Volume-rendered digital subtraction CTA image (C) shows an aneurysm in the right posterior communicating artery (red arrow), which is confirmed by 2D-DSA (D).
- Fig 2.
An 80-kVp cerebral CTA with 30 mL of contrast agent in a 45-year-old man. Maximum-intensity-projection image (A) and a volume-rendered digital subtraction CTA image (B) show an aneurysm in the right middle cerebral artery (red arrow), which is confirmed by 3D-DSA (C).
- Fig 3.
False-negative aneurysms in the 2 CTA protocols. A and B, An 80-kVp cerebral CTA with 30 mL of contrast agent in a 50-year-old man. A volume-rendered digital subtraction CTA image (A) shows 2 true-positive aneurysms in the anterior communicating artery and right middle cerebral artery, respectively (yellow arrows), while another 2 small aneurysms with diameters of 1.1 and 0.6 mm were found in the right middle cerebral artery (white arrows) on 3D-DSA (B), which were not found in the CTA image. C and D, A 120-kVp cerebral CTA with 60 mL of contrast agent in a 46-year-old man. The volume-rendered digital subtraction CTA image (C) shows a true-positive aneurysm in the left anterior choroidal artery (red arrow) and a false-negative aneurysm in the left posterior communicating artery (yellow arrow). The aneurysm in the left posterior communicating artery (yellow arrow) was found at repeat interpretation. 3D-DSA shows the 2 aneurysms (D).
- Fig 4.
A 120-kVp cerebral CTA with 60 mL of contrast agent in a 70-year-old woman. A and B, Volume-rendered digital subtraction CTA images show a true-positive aneurysm in the top of basilar artery (red arrow), which was confirmed by 3D-DSA (C) and a false-positive aneurysm in the left middle cerebral artery (yellow arrow), which was not evident in 2D-DSA.
Tables
Approach Results (No.) Statistical Analysis (%) TP TN FP FN Sensitivity Specificity PPV NPV Accuracy Per patient Group A 60 39 1 2 96.8 (89.0–99.1) 97.5 (87.1–99.6) 98.4 (91.2–99.7) 95.1 (83.9–98.7) 97.0 (91.7–99.0) Group B 58 42 1 1 98.3 (91.0–99.7) 97.7 (87.9–99.6) 98.3 (91.0–99.7) 97.7 (87.9–99.6) 98.0 (93.1–99.5) Per aneurysm Group A 77 39 3 10 88.5 (81.6–95.4) 92.9 (88.6–98.6) 96.3 (91.3–100.0) 79.6 (67.3–89.8) 89.9 (84.5–94.6) Group B 66 42 3 4 94.3 (88.6–98.6) 93.3 (84.4–100.0) 95.7 (89.9–100.0) 91.3 (82.6–97.8) 93.9 (88.7–98.3) Note:—TP indicates true positive; TN, true negative; FP, false positive; FN, false negative.
↵a The data in parentheses are 95% confidence intervals.
Aneurysm Size Results (No.) Statistical Analysis (%) TP TN FP FN Sensitivity Specificity PPV NPV Accuracy <3 mm Group A 24 39 2 8 75.0 (59.4–90.6) 95.1 (87.8–100.0) 92.3 (80.8–100.0) 83.0 (72.3–93.6) 86.3 (78.1–93.2) Group B 17 42 2 4 81.0 (61.9–95.2) 95.5 (88.6–100.0) 89.5 (73.7–100.0) 91.3 (82.6–97.8) 90.8 (83.1–96.9) 3–8 mm Group A 44 39 1 2 95.7 (89.1–100.0) 97.5 (92.5–100.0) 97.8 (93.3–100.0) 95.1 (87.8–100.0) 96.5 (93.0–100.0) Group B 38 42 1 0 100 (100.0–100.0) 97.7 (93.0–100.0) 97.4 (92.3–100.0) 100 (100.0–100.0) 98.8 (96.3–100.0) >8 mm Group A 9 39 0 0 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) Group B 11 42 0 0 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) 100 (100.0–100.0) Note:—TP indicates true positive; TN, true negative; FP, false positive; FN, false negative.
↵a The data in parentheses are 95% confidence intervals.
Location Results (No.) Statistical Analysis (%) TP TN FP FN Sensitivity Specificity PPV NPV Accuracy Anterior circulation Group A 50 39 1 8 86.2 (77.6–94.8) 97.5 (92.5–100.0) 98.0 (94.1–100.0) 83.0 (70.2–93.6) 90.8 (84.7–95.9) Group B 28 42 2 2 93.3 (83.3–100.0) 95.5 (88.5–100.0) 93.3 (83.3–100.0) 95.5 (88.6–100.0) 94.6 (89.2–98.6) Posterior circulation Group A 27 39 2 2 93.1 (82.8–100.0) 95.1 (87.8–100.0) 93.1 (82.8–100.0) 95.1 (87.8–100.0) 94.3 (88.6–98.6) Group B 38 42 1 2 95.0 (87.5–100.0) 97.7 (93.0–100.0) 97.4 (92.3–100.0) 95.5 (88.6–100.0) 96.4 (91.6–100.0) Note:—TP indicates true positive; TN, true negative; FP, false positive; FN, false negative.
↵a The data in parentheses are 95% confidence intervals.
