Article Figures & Data
Figures
- Fig 1.
Signal intensity versus time.
A, Mean signal intensity as a function of time from an ROI placed within the proximal intracranial branch of the MCA. The start-stop interval is used to define the mean baseline signal intensity, while the stop-last interval represents the first pass of the contrast bolus. Note that subsequent decreases in signal intensity occur as the contrast material is recirculated.
B, Gamma-variate fit (solid line) to the baseline subtracted and inverted data (dashed line). The two variables used to quantify the curve are the first moment of the gamma-variate fit, termed the first-moment transit time (TTFM), and the area under the fitted curve (relative cerebral blood volume [rCBV]).
- Fig 2.
Placement of the ROIs.
A, PCAT.
B, MCAT1.
C, MCAT2.
D, ACAT.
- Fig 3.
Perfusion data obtained at the level of the lateral ventricles in a patient with a symptomatic 95% stenosis in the left ICA and a 50% stenosis of the contralateral ICA.
A, Preintervention rCBV map.
B, Preintervention TTFM map.
C, Gamma-variate fits corresponding to the depicted regions show a longer TTFM and a smaller rCBV in the symptomatic hemisphere.
D, Postintervention rCBV map.
E, Postintervention TTFM map.
F, Corresponding gamma-variate fits. Note the resolution of interhemispheric asymmetry in TTFM.
Tables
Subject/Sex/Age, y Presenting Symptoms ICA Stenosis, % Time between MR Examinations, h:min Symptomatic Side Asymptomatic Side 1/F/74 Amaurosis fugax 90 0 06:31 2/M/58 Nondisabling stroke 95 50 03:59 3/F/72 Amaurosis fugax 85 <30 03:52 4/F/61 Transient ischemic attack 95 <30 03:39 5/F/79 Transient ischemic attack 90 <30 02:13 6/M/71 Transient ischemic attack 85 50 02:57 7/F/75 Amaurosis fugax 80 70 04:30 8/M/58 Nondisabling stroke 66 0 06:16 9/M/71 Transient ischemic attack 80 0 03:07 10/M/62 Minor stroke 95 30 06:13 11/M/76 Amaurosis fugax 90 0 03:17 ROI rCBVR ΔTTFM, seconds Before Intervention After Intervention Before Intervention After Intervention PCAT 0.98 ± 0.17 0.96 ± 0.26 −0.14 ± 0.42 −0.02 ± 0.68 MCAT1 1.01 ± 0.19 0.91 ± 0.18 1.31 ± 1.15* 0.51 ± 0.61†‡ MCAT2 1.06 ± 0.27 1.00 ± 0.13 1.09 ± 0.90* 0.57 ± 0.75† ACAT 1.11 ± 0.36 1.01 ± 0.51 0.12 ± 0.64 0.16 ± 0.66 Note.—Data are the mean ± standard deviation. For cases of inter-hemispheric symmetry, the rCBVR was 1, and ΔTTFM was 0 seconds.
* Statistically significant interhemispheric asymmetry in mean TTFM, P < .005.
† Statistically significant interhemispheric asymmetry in mean TTFM, P < .05.
‡ Significant difference in mean ΔTTFM before and after intervention, P < .05.
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