Article Figures & Data
Figures
- Fig 1.
Group 1. MR images obtained 2 hours after cat brains were embolized with triolein show type 1 (solid arrow) and type 2 (open arrows) lesions. Type 2 lesions are bigger than type 1 lesions.
A, T2-weighted (3000/96/2 [TR/TE/NEX]) image. Type 1 and type 2 lesions are hyperintense.
B, Contrast-enhanced T1-weighted (320/30/2) image. Type 1 lesions show mild enhancement. Type 2 lesions show enhancement.
C, Diffusion-weighted image. Type 1 lesions are hyperintense. Type 2 lesions have isointensity or slight hyperintensity.
D, ADC map. Type 1 lesions are hypointense. Type 2 lesions are isointense.
- Fig 2.
Group 2. MR images obtained 2 hours after cat brains were embolized with oleic acid group show type 1 (solid arrow) and type 2 (open arrows) lesions.
A, T2-weighted (3000/96/2) image. Type 1 lesions have mild hyperintensity. Type 2 lesions are hyperintense.
B, Contrast-enhanced T1-weighted (320/30/2) image. Type 1 lesions show less enhancement than do type 2 lesions, which show strong enhancement.
C, Diffusion-weighted image. Type 1 lesions are hyperintense. Type 2 lesions have isointensity or mild hyperintensity.
D, ADC map. Type 1 lesions are hypointense. Type 2 lesions are isointense.
- Fig 3.
Bar graph of the signal intensity ratios on T2-weighted images. At 2 hours, the ratios in type 1 and type 2 lesions increase significantly in both groups (P < .001). The ratios of type 1 lesions are significantly higher in group 2 compared with group 1 at both 30 minutes and 2 hours (P = .013). However, in type 2 lesions, the ratios do not significantly differ in either group at either time (P > .643).
- Fig 4.
Bar graph of the signal intensity ratios on the ADC maps. Compared with the baseline value at 30 minutes, the ratios in types 1 and type 2 lesions did not change significantly at 2 hours in either group (P > .485). With the type 1 lesions, the ratios in group 2 were significantly lower than those in group 1 at each time point (P = .027). However, in type 2 lesions, the ratios were not significantly different in either group (P > .144).
- Fig 5.
Bar graph of the signal intensity ratios on contrast-enhanced T1-weighted images. Compared with the baseline values at 30 minutes, the ratios in type 1 lesions increase significantly at 2 hours in both groups (P = .034). In type 1 lesions, the ratios are not significantly different between group 1 and 2 at each time point (P > .051). However, in type 2 lesion, the ratios in group 1 are higher than those in group 2 at each time point (P < .001).
- Fig 6.
Electron microscopy findings in a type 1 lesion in a cat brain from group 1, which was treated with triolein (original magnification ×3000). Photomicrograph shows an intravascular fat vacuole (F) and defects in the endothelial wall (solid arrows). Areas of perivascular interstitial edema (asterisk) and neuropil swelling (arrowhead) are smaller than 5 μm in diameter. Open arrows represent red blood cells. Bar indicates 2 μm.
- Fig 7.
Electron microscopy findings in a type 1 lesion in a cat brain from group 1, which was treated with triolein (original magnification ×5000). The huge intravascular fat vacuole (F) distends the lumen and compresses the endothelial wall. The endothelial wall (arrows) is partly disrupted. Widening of the perivascular interstitial space (asterisks) is mild. Bar indicates 1 μm.
- Fig 8.
Electron microscopy findings in a type 1 lesion in a cat brain from group 2, which was treated with oleic acid (original magnification ×4000). Neuropil cells (arrowheads) are edematous, and widening of the interstitial space (asterisk) is prominent. Bar indicates 2 μm.
- Fig 9.
Electron microscopy findings in a type 1 lesion in a cat brains from group 2, which was treated with oleic acid (original magnification ×5000). A 5-μm intravascular fat vacuole (F) is shown. Neuropil swelling (arrowheads) is prominent, and widening of the perivascular interstitial space (asterisk) is also observed. Bar indicates 1 μm.
Tables
Group and Lesion Signal Intensity Ratio At 30 min At 2 h 1, triolein (n = 8) Type 1 (n = 7) 1.14 (0.08)* 1.41 (0.08)* Type 2 (n = 8) 1.21 (0.15) 1.36 (0.09) 2, oleic acid (n = 10) Type 1 (n = 8) 1.23 (0.10)* 1.67 (0.24)* Type 2 (n = 10) 1.15 (0.14) 1.36 (0.17) Note.—The data are the mean ± SD.
* In type 1 lesions, the signal intensity ratios were significantly higher in group 2 compared with group 1 at both 30 minutes and 2 hours (P < .013). However, in type 2 lesions, the signal intensity ratios did not significantly differ between the two groups at either time point (P > .643).
Group and Lesion Signal Intensity Ratio At 30 min At 2 h 1, triolein (n = 8) Type 1 (n = 7) 0.72 (0.12) 0.67 (0.12) Type 2 (n = 8) 0.97 (0.16) 1.12 (0.28) 2, oleic acid (n = 10) Type 1 (n = 8) 0.61 (0.08) 0.60 (0.11) Type 2 (n = 10) 0.91 (0.18) 0.95 (0.13) Note.—The data are the mean ± SD. In type 1 lesions, the signal intensity ratios were significantly lower in group 2 compared with those in group 1 at both 30 minutes and 2 hours (P = .027). However, in type 2 lesions, the signal intensity ratios did not significantly differ between the two groups at either time point (P = .144).
- TABLE 3:
Mean signal intensity ratios of the lesions on contrast-enhanced T1-weighted images
Group and Lesion Signal Intensity Ratio At 30 min At 2 h 1, triolein (n = 8) Type 1 (n = 7) 1.29 (0.22) 1.53 (0.22) Type 2 (n = 8) 1.94 (0.42)* 1.92 (0.45)* 2, oleic acid (n = 10) Type 1 (n = 8) 1.09 (0.18) 1.31 (0.19) Type 2 (n = 10) 1.36 (0.19)* 1.43 (0.12)* Note.—The data are the mean ± SD. The signal intensity ratios of type 1 lesions were not significantly different between groups 1 and 2 at either time point (P > .051).
* The signal intensity ratios in type 2 lesions were higher in group 1 compared with group 2 at both time points (P < .001).
