Article Figures & Data
Figures
- FIGURE 1.
133Xe CBF images at rest (top row) and after ACZ enhancement (bottom row) with placement of regions of interest. Mean CBF is calculated in MCA territories on 4 slices from basal ganglia through centrum semiovale. CPR is defined as percentage increase in CBF after ACZ enhancement, or CPR = [(CBF [ACZ] − CBF [rest])/CBF (rest)] × 100 (%).
- FIGURE 2.
Comparisons of visual analysis and L/N ratio. Visual interpretation agrees well with L/N ratio. All cases of moderate or severe hypoperfusion show L/N ratios less than 0.9.
- FIGURE 3.
A 63-y-old woman (patient 4) with giant aneurysm of right ICA. (A) Right ICA angiogram shows giant aneurysm in carotid siphon. (B) Left ICA angiogram during BOT of right ICA shows good collateral cross-flow. (C) 99mTc-ECD SPECT images demonstrate symmetric cerebral uptake (L/N of 0.96), and no neurologic symptoms were observed. This patient was considered to be tolerant of carotid occlusion. However, after proximal occlusion of right ICA, she showed transient left hemiparesis when her blood pressure dropped. Her hemiparesis disappeared immediately after injection of vasoconstrictor, and no infarction developed. (D) 133Xe-CBF SPECT revealed normal CBF at rest but decreased CPR in right cerebral hemisphere (mean CPR in right MCA territory was −13% on day 11) (arrows). On follow-up, impaired CPR gradually improved.
- FIGURE 4.
Comparisons of CBF and CPR before and after permanent carotid occlusion. (A) CBF changed slightly (54 ± 8 mL/100 g/min vs. 52 ± 6 mL/100 g/min, not significant (NS)). (B) CPR significantly decreased in all patients after permanent carotid occlusion (35% ± 7% vs. 7% ± 14%, P < 0.05). In 5 of 7 patients, CPR decreased below normal range (CPR < 15%), and steal phenomenon was observed in 3 patients.
- FIGURE 5.
Changes in CBF and CPR on follow-up after permanent carotid occlusion. (A) CBF changed within normal range (CBF ≥ 43 mL/100 g/min). (B) In contrast, decreased CPR gradually improved after permanent carotid occlusion.
Tables
Patient no. Age Sex Disease Site of occlusion Treatment CBF (mL/ 100 g/min) CPR (%) Symptoms (BOT) Infarction (CT/MRI) Before After Before After 1 64 F Aneurysm R ICA Ligation 54 49 33 −2 Absent Absent 2 59 F Aneurysm R ICA Balloon occlusion 44 43 36 14 Absent NA 3 49 F Aneurysm R ICA Balloon occlusion 56 60 39 27 Absent Absent 4 63 F Aneurysm R ICA Coil embolization 67 56 34 −13 Present* Absent 5 70 F Aneurysm R ICA Balloon occlusion 44 53 23 −2 Absent Present† 6 66 M Aneurysm R ICA Balloon occlusion 54 49 48 18 Absent Absent 7 36 F Aneurysm L ICA Trapping 58 55 34 4 Absent Absent
