Article Figures & Data
Figures
- Fig 1.
Optic glioma.
A, Sagittal spin-echo image (TR, 643 ms; TE, 12 ms) shows markedly enlarged optic nerve (arrow).
B, Axial fast spin-echo (TR, 6000 ms; TE, 84 ms) image shows bilateral enlargement, along with tortuosity of intraorbital optic nerves (arrow).
- Fig 2.
Tortuosity of optic nerves
A, Axial fast spin-echo T2-weighted image showing factor 1: interruption of the optic nerve out of the axial plane (tip of arrow) without return.
B, Axial fast spin-echo T2-weighted image showing factor 2: interruption of the optic nerve out of the axial plane (tip of arrow) with return of the nerve into the axial plane.
C, Axial fast spin-echo T2-weighted image showing factor 3: deviation of the optic nerve within the axial plane (arrow).
D, Sagittal T1-weighted image showing factor 4: increased curvature (tip of arrow) in the sagittal plane.
E, Coronal fast spin-echo T2-weighted image showing factor 5: lack of congruity of the optic nerves (arrow) in the coronal plane.
F, Coronal fast spin-echo T2-weighted image showing factor 6: dilation of the subarachnoid space (encircled by arrows) surrounding anterior portion of optic nerves.
Tables
Case No. Definitely Not Tortuous Probably Not Tortuous Toss-Up Probably Tortuous Definitely Tortuous 1 ••• ○○○ ○○○ ○○○ ○○○ 2 ○○• ••○ ○○○ ○○○ ○○○ 3 ○○○ ○○○ ○○○ •○○ ○•• 4 ○○○ ○○○ ○○○ ○○○ ••• 5 ••• ○○○ ○○○ ○○○ ○○○ 6 ○○○ ○○○ ○○○ ○○○ ••• 7 •○○ ○○○ ○○○ ○○• ○•○ 8 •○• ○○○ ○•○ ○○○ ○○○ 9 ••• ○○○ ○○○ ○○○ ○○○ 10 ••• ○○○ ○○○ ○○○ ○○○ 11 ○○○ ○○○ ○○○ ○○○ ••• 12 ○○○ ○○○ ○○○ ○○• ••○ 13 ○○○ ○○○ ○○○ ○○○ ••• 14 ○○○ •○○ ○○○ ○○• ○•○ 15 ••• ○○○ ○○○ ○○○ ○○○ 16 ○○○ ○○○ ○○○ ••○ ○○• 17 ○○○ ○○○ ○○○ ○○○ ••• 18 ○○○ ○○○ ○○○ •○• ○•○ 19 •○○ ○○• ○○○ ○○○ ○•○ 20 ○○• ○○○ ○•○ ○○○ •○○ 21 ••• ○○○ ○○○ ○○○ ○○○ 22 ••• ○○○ ○○○ ○○○ ○○○ 23 ••○ ○○• ○○○ ○○○ ○○○ 24 ○○○ •○• ○○○ ○•○ ○○○ 25 ○○○ ○○○ •○○ ○•• ○○○ 26 ○○○ ○○○ ○○• ○○○ ••○ 27 ••• ○○○ ○○○ ○○○ ○○○ 28 ••• ○○○ ○○○ ○○○ ○○○ Column Perfect Agreement 9 0 0 0 5 14/28 = 50% Column Majority Agreement 11 2 0 3 8 23/28 = 82% Dichotomous Agreement 12 9 21/28 = 75% Note:—• represents, for a given case, the response on the Likert scale that best describes the presence of tortuosity as read by 1 of 3 individual radiologists.
Case No. Radiographic Factor 1 Out Axial Plane 2 Out/In Axial Plane 3 Deviation within Axial Plane 4 Curvature Sagittal Plane 5 Lack of Coronal Congruity 6 Dilation Subarachnoid Space Mean Total Score 1 ○○○ ○○○ ○○○ ○○○ n/a ○○○ 2 ○○• ••○ ○○• ••• ○○○ ○○○ 2.3 3 ○○○ ○•• ••• ○•• ••• ••• 4.3 4 ••○ ○○• ••• ○•• ••• ••• 4.7 5 ○○○ ○○○ ○○○ ○○○ ○○○ ○○○ 0 6 ••○ ○○• ••• ••• •○• •○• 4.3 7 ○○○ ○•• ○•○ ○•• ○•○ ○•• 2.7 8 ○○○ ○○○ ○•• ○○○ n/a ○○○ 9 ○○○ ○○○ ○○○ ○○○ ○○○ ○○○ 0 10 ○○○ ○○○ ○○○ ○○○ n/a ○○• 11 ○○○ ○•• ••• ••• ••• ••• 4.7 12 ○○○ ○•• ••• ••• ••• ••• 4.7 13 ○•○ •○• ••• ••• ••• ••• 5.0 14 ○•○ ○○• ○•• ••• ○•○ ••○ 3.3 15 ○○○ ○○○ ○○○ ○○○ ○○○ ••• 1.0 16 ○○○ ••• •○○ ••• •○• ••• 4.0 17 ○○○ ○•• ••• ••○ ••• ••• 4.3 18 ○○○ ••• ••○ ••• ••• ••○ 4.3 19 ○○○ ••• ○○○ ○•• ○○○ ○•○ 2.0 20 ••• ○○○ ••• ○○○ ○•○ ○○○ 2.3 21 ••• ○○○ ○○○ ○○• ○○○ ○○○ 1.3 22 ••• ○○○ ○○○ n/a ○○○ •○○ 23 ○•• ○○• ○○○ ••• ○○○ ○○○ 2.0 24 ○○○ ○○• ••• ○○• ○•○ •○○ 2.3 25 ○○○ ○•• ••• •○• ○•• ○○○ 3.0 26 ○○○ ••• •○○ ••• ••• •○○ 3.7 27 ○○○ ○○○ ○○○ ○○○ ○○○ ○○○ 0 28 ••• ○○○ ○○○ ○○○ ○○○ •○○ 1.3 Column Perfect Agree 22/28 = 79% 15/28 = 54% 21/28 = 75% 19/27 = 70% 18/25 = 72% 18/28 = 64% Note:—Radiologist decision: ○, factor absent; •, factor present; n/a, not available for review.
- Table 3:
Univariate analysis of radiographic factors for predicting a diagnosis of tortuosity
Variable Univariate OR for Prediction of Tortuosity 1 .67 (CI .22–2.1) 2 4.6 (CI 1.7–12.7) 3 14.4 (CI 4.2–49-8) 4 7.9 (CI 2.3–26.6) 5 23.6 (CI 6.5–85.4) 6 28.6 (CI 7.1–114.7) Note:—OR indicates odds ratio; CI, 95% confidence interval.
Radiographic Factor Combination Concordance Statistic Sensitivity Specificity Factors 5 & 6 .903 89 (CI .79–1) 93 (CI .86–1) Factors 3, 5, & 6 .911 85 (CI .66–1) 93 (CI .86–1) Factors 3 & 6 .898 85 (CI .66–1) 91 (CI .83–.98) Factor 5 .826 93 (CI .83–1) 80 (CI .64–.94) Factor 6 .832 93 (CI .83–1) 76 (CI .58–.91) Factor 3 .780 89 (CI .71–1) 69 (CI .46–.86) Note:—CI indicates 95% confidence interval.
Radiographic Factor Combination Likelihood Ratio Factors Present 5 & 6 13.3 (CI 6.4–46.1) 3, 5, & 6 12.7 (CI 6.0–44) 3 & 6 9.6 (CI 4.8–34.2) 5 4.6 (CI 2.3–11.5) 6 3.8 (CI 2.2–9.7) 3 2.8 (CI 1.6–7.1) Factors Absent 3 .16 (CI 0–.49) 6 .10 (CI 0–.26) 5 .09 (CI 0–2.4) 3 & 6 .07 (CI 0–.27) 5 & 6 .06 (CI 0–.22) 3, 5, & 6 0* Note:—CI indicates 95% confidence interval.
* Unable to calculate confidence interval.
