Article Figures & Data
Figures
- Fig. 1.
A 22-year-old man with HIVD at L5-S1. On T2-weighted sagittal MR imaging (TR/TE, 4200/100), the herniated disk is wasted by the PLL and it resembles budding (arrows).
- Fig. 2.
A 65-year-old man with a subligamentous HIVD at L4–5. T1-weighted axial (A) and T1-weighted sagittal (B) MR images (TR/TE, 500/10 ms) show the intact low-signal-intensity line covering the HIVD.
- Fig. 3.
A 36-year-old man with an extraligamentous HIVD at L5-S1. A, T2-weighted axial MR image (TR/TE, 4200/100 ms) shows disruption of the continuous low-signal-intensity line covering the herniated disk (arrow) and the internal dark line (arrowhead). B, T1-weighted sagittal MR image (TR/TE, 500/10 ms) shows disruption of the continuous low-signal-intensity line covering the herniated disk (arrow).
- Fig. 4.
A 47-year-old man with extraligamentous HIVD at L5-S1. On the T2-weighted axial MR image (TR/TE, 4200/100 ms), the internal dark line (arrow) is interposed in the herniated disk.
Tables
- Table 1:
Evaluation of MR imaging criteria for indicating extraligamentous HIVD in the lumbar spine
MR Imaging Criteria Sensitivity (%) Specificity (%) Accuracy (%) P Value Presence of disk migration 50/66 (75.8) 20/51 (39.2) 70/117 (59.8) .0817 Budding appearance in HIVD 15/66 (22.7) 43/51 (84.3) 58/117 (49.6) .3427 Spinal canal compromised for more than half its dimension 30/66 (45.5) 42/51 (82.4) 72/117 (61.5) .0015 Internal signal difference in HIVD 23/66 (34.8) 42/51 (82.4) 65/117 (55.6) .0385 Ill-defined margin of HIVD 10/66 (15.2) 49/51 (96.1) 59/117 (50.4) .0471 Disruption of continuous low-signal-intensity line covering HIVD 38/66 (57.6) 40/51 (78.4) 78/117 (66.7) <.0001 Presence of internal dark line in HIVD 20/66 (30.3) 46/51 (90.2) 66/117 (56.4) .0072 Adjacent bone marrow corner erosion 35/66 (53.0) 29/51 (56.9) 64/117 (48.6) .2877 Bone marrow corner edema 19/66 (28.8) 42/51 (82.4) 61/117 (52.1) .1615 Severe height loss of original disk 61/66 (92.4) 6/51 (11.8) 67/117 (57.3) .3238 MR Imaging Criteria Sensitivity (%) Specificity (%) Accuracy (%) PPV (%) NPV (%) Odds Ratio/P Value Spinal canal compromised for more than half its dimension 30/66 (45.5) 42/51 (82.4) 72/117 (61.5) 30/39 (76.9) 42/78 (53.8) 3.88/.0015 Internal signal difference in HIVD 23/66 (34.8) 42/51 (82.4) 65/117 (55.6) 23/32 (71.9) 42/85 (49.4) 2.49/.0385 Ill-defined margin of HIVD 10/66 (15.2) 49/51 (96.1) 59/117 (50.4) 10/12 (83.3) 49/105 (46.7) 4.37/.0471 Disruption of continuous low-signal-intensity line covering HIVD 38/66 (57.6) 40/51 (78.4) 78/117 (66.7) 38/49 (77.6) 40/68 (58.8) 4.93/<.0001 Presence of internal dark line in HIVD 20/66 (30.3) 46/51 (90.2) 66/117 (56.4) 20/25 (80.0) 46/92 (50.0) 4.00/.0072 Combination of 5 MR imaging criteria 51/66 (77.3) 38/51 (74.5) 89/117 (76.1) 51/64 (79.7) 38/53 (71.7) 9.93/<.0001
