Article Figures & Data
Figures
- Fig 1.
Flowchart illustrating study selection.
- Fig 2.
Axial fat-suppressed T2-weighted spectral adiabatic inversion recovery (SPAIR) images just distal to the greater sciatic foramen. A, Grade 0 nerve signal in a normal right sciatic nerve (circle). B, Grade I nerve signal abnormality shows a mildly hyperintense right sciatic nerve but less intense than the adjacent vasculature. C, Grade II nerve signal abnormality, similar to that of adjacent veins.
- Fig 3.
Coronal fat-suppressed T2 SPAIR (A and B), axial fat-suppressed T2 SPAIR (C), and maximum-intensity reconstruction of 3D coronal fat-suppressed T2 STIR (D) reveal marked abnormal asymmetric signal involving the left L4 nerve root extending to the left femoral nerve (arrows, A, B, and D). Signal abnormality also extends along the left obturator nerve (dashed arrow, A), also supplied by the L4 nerve root. An axial slice through the L3–L4 level (C) shows a disc extrusion (arrow, C) compressing the left L4 nerve root, accounting for the nerve inflammation.
- Fig 4.
3D coronal fat-suppressed T2 STIR (A), coronal fat-suppressed T2 SPAIR (B), axial T1 (C), and axial fat-suppressed T2 SPAIR (D) images show a typical example of right sciatic neuropathy. There is abnormal signal in the right sciatic nerve (arrows) through the greater sciatic foramen (circle, C), a characteristic location of piriformis-related sciatic nerve compression. There is corresponding asymmetric signal of the right sciatic nerve compared with the left (circle, D).
- Fig 5.
Coronal T1 (A), maximum-intensity reconstruction of 3D coronal fat-suppressed T2 STIR (B), and sequential coronal fat-suppressed T2 SPAIR (C–E) images show abnormal signal of the left L4, left femoral (dashed arrow, B) and left obturator (arrows) nerves. There is also abnormal intramuscular T2 hyperintense signal in the left iliacus muscle (circle, B). This patient had a long-standing history of type 2 diabetes, and signal abnormality was attributed to diabetic amyotrophy.
Tables
Sequence Matrix TR (ms) TE (ms) NEX FOV (cm) In-Plane Resolution (mm) Slice Thickness (mm) Acquisition Time (min: sec) Axial T1 TSE 320 × 240 663 12 2 31 1.0 × 1.3 3.5 6:18 Axial T2 FS SPAIR 320 × 192 6220 83 2 31 1.0 × 1.6 3.5 7:52 Coronal T1 384 × 216 3160 9.9 1 36 1.0 × 1.7 3 3:49 Coronal PD SPAIR 320 × 224 4380 35 2 36 1.1 × 1.6 3 4:10 3D Coronal SPACE STIR 256 × 256 1500 119 1.4 38 1.5 × 1.5 1.5 8:23 Sagittal T2 Dixon (lumbar spine) 448 × 300 4160 83 2 28 0.6 × 0.9 3 3:59 Note:—PD indicates proton density; SPACE, sampling perfection with application-optimized contrasts by using different flip angle evolution (Siemens); FS, fat suppressed.
↵a All lumbosacral plexus MR imaging was performed on a 3T Magnetom Skyra (Siemens) scanner without contrast.
Variable Value Range/Percentage Subjects 64 Age (yr) 57 20–84 Sex (male) 33 51.6% Symptom duration (mo) 26 1–312 Diabetes 12 18.8% Prior surgery 9 14.1% Weakness 29 45.3% Numbness 31 48.4% Leg pain 48 75.0% Back pain 28 43.8% Tingling 23 35.9% MRN intraneural T2 signal abnormality (grade I or II) 28 43.8% MRN evidence of muscular denervation 8 12.5% EMG findings of active radiculopathy 20 31.3% Correlations ϕ Coefficient/Cramér V P Value Denervation/subjective weakness 0.13 .30 Denervation/objective weakness 0.21 .10 Denervation/objective atrophy 0.33 .02 MRN intraneural signal/EMG active radiculopathy 0.79 <.001 MRN laterality/EMG laterality 1.00 <.001
Jump to section
Related Articles
Cited By...
- No citing articles found.