Article Figures & Data
Figures
- Fig 1.
Axial T1WI with fat saturation after Gd-DTPA. Areas outlined in color represent manually defined ROIs corresponding to injured nerve (red), contralateral nerve (yellow), muscle (green), and background/air (blue). Precontrast and nonenhancing nerves were localized by correlating T1WI and T2WI findings.
- Fig 2.
Axial T2WI with fat saturation (#5 Jeweler forceps injury, day 13). A, Injured sciatic nerve (arrows) shows increased caliber and signal compared with the nonoperative contralateral nerve. A small focus of susceptibility artifact (open arrow) is seen at the site of injury, presumably representing blood products. B, The adjacent section shows T2 hyperintensity in a distal branch (arrow) of the injured sciatic nerve.
- Fig 3.
Axial T1WI with fat saturation, pre- (A) and post- (B–D) Gd-DTPA (same animal as in Fig 2). A, On precontrast images, both injured and nonoperative nerves are isointense to muscle. B, Intense Gd-DTPA enhancement (open arrows) is demonstrated a few millimeters proximal to, in the region of, and distal to the site of crush injury (arrow) (On-line Video 1). C, The nonoperative contralateral nerve (arrows) is well seen in this section and demonstrates a thin rim of peripheral enhancement but no internal enhancement (On-line Video 2). D, Enhancement is seen in a distal branch (arrow) of the injured sciatic nerve (On-line Video 3).
- Fig 4.
Axial T1WI pre- (left) and post- (right) Gd-DTPA with fat saturation acquired at days 7 (A and B), 13 (C and D), and 21 (E and F) after severe (forceps) crush injury. Robust enhancement of injured nerves is seen at all 3 time points (arrows).
- Fig 5.
Peak enhancement after severe (forceps) crush injury compared with normal muscle between days 3 and 21. Enhancement is expressed as the percentage increase of the signal-to-noise ratio after Gd-DTPA administration. Error bars represent 1 SD.
- Fig 6.
ROI signal-to-noise ratio as a function of time after the intravenous administration of Gd-DTPA (same animal as in Figs 2 and 3). The presence of a delayed, higher peak suggests an enlarged extravascular extracellular space after severe (forceps) crush injury (On-line Video 4).13
- Fig 7.
ROI signal-to-noise ratio as a function of time after the intravenous administration of Gd-DTPA (same animal as in Figs 2, 3, and 6). The half-life of Gd-DTPA enhancement was approximately 1 hour after severe (forceps) crush injury.
Tables
- Table 1:
Number of MRI sessions at each time point after forceps (#5 jeweler or toothed Adson) crush injury
Forceps: Postop Day No. No. MRI Sessions (with Limited DCE) 0 1 (0) 1 4 (0) 2 2 (0) 3 3 (2) 4 1 (0) 5 1 (0) 7 6 (5) 12 2 (0) 13 2 (1) 14 5 (4) 19 1 (1) 21 1 (1) 22 1 (1) 30 1 (1) Total 31 (16) Note:—Postop indicates postoperative.
- Table 2:
Number of MRI sessions at each time point after clip (10–60 g microvascular/microaneurysm) crush injury
Clip: Postop Day No. No. MRI Sessions 1 3 2 4 3 2 4 3 5 4 6 1 7 2 Total 19
