Table 4. Magnetic Resonance Imaging Findings at 6 to 12 Months and 0 to 12 Months.
| Measure | Months 6-12 | Months 0-12 | ||||||
|---|---|---|---|---|---|---|---|---|
| PTA (n = 70) | Sham (n = 33) | P Value | Adjusted P Valuea | PTA (n = 73) | Sham (n = 37) | P Value | Adjusted P Valuea | |
| New combined brain lesionsb | ||||||||
| No. of lesions, mean (SD) | 0.47 (1.19) | 1.27 (2.65) | NA | NA | 1.40 (4.21) | 1.95 (3.73) | NA | NA |
| Mean lesion ratio (95% CI)c | 0.37 (0.15-0.91) | .03 | .09 | 0.72 (0.32-1.63) | .45 | .45 | ||
| Median (range) | 0 (0-7) | 0 (0-13) | NA | NA | 0 (0-31) | 1 (0-8) | NA | NA |
| Patients free of lesions, No. (%) | 58 (79.5) | 22 (59.5) | NA | NA | 46 (63.0) | 18 (48.7) | NA | NA |
| Lesion free, OR (95% CI)d | 2.64 (1.11-6.28) | .03 | .09 | 1.80 (0.81-4.01) | .15 | .30 | ||
| New or enlarged T2 lesions | ||||||||
| No. of lesions, mean (SD) | 0.36 (0.98) | 1.14 (2.63) | NA | NA | 1.10 (3.03) | 1.59(3.42) | NA | NA |
| Mean lesion ratio (95% CI)c | 0.31 (0.11-0.86) | .02 | .06 | 0.69 (0.28-1.67) | .41 | .82 | ||
| Median (range) | 0 (0-5) | 0 (0-13) | NA | NA | 0 | 0 (0-18) | NA | NA |
| Patients free of lesions, No. (%) | 61 (83.6) | 24 (64.9) | NA | NA | 50 (68.5) | 21 (56.8) | NA | NA |
| Lesion free, OR (95% CI)d | 2.75 (1.10-6.89) | .03 | .09 | 1.66 (0.73-3.75) | .22 | .62 | ||
| Gadolinium-enhancing T1 lesions | ||||||||
| No. of lesions, mean (SD) | 0.36 (1.08) | 0.59 (1.55) | NA | NA | 1.07 (4.11) | 1.06 (2.47) | NA | NA |
| Mean lesion ratio (95% CI)c | 0.60 (0.20-1.75) | .35 | .35 | 1.01 (0.35-2.93) | .98 | .98 | ||
| Median (range) | 0 (0-7) | 0 (0-9) | NA | NA | 0 | 0 (0-14) | NA | NA |
| Patients free of lesions, No. (%) | 62 (84.9) | 26 (70.3) | NA | NA | 53 (76.8) | 18 (54.6) | NA | NA |
| Lesion free, OR (95% CI)d | 2.38 (0.92-6.19) | .07 | .14 | 2.76 (1.14-6.68) | .02 | .08 | ||
Abbreviations: NA, not applicable; OR, odds ratio; PTA, percutaneous transluminal angioplasty.
a
P values adjusted for multiplicity using Hommel method.
b
New combined lesions included new lesions on T2-weighted images, preexisting lesions enlarged by >30% on T2-weighted images, and gadolinium-enhancing lesions in T1-weighted images of preexisting lesions (no enlarged T2 lesions were observed).
c
Estimated effect of PTA on number of lesions; negative-binomial model was used to derive P values.
d
Estimated effect of PTA on proportion lesion-free patients; χ2 test was used to derive P values.