Table 2. Clinical comments concerning Figures 4 and 5.
| Subject | Detailed diagnosis | CVR map and z-map description |
|---|---|---|
| 1 | Previous Hx of stroke. Presented with R TIAs. Angiography shows R ICA occlusion and VA stenosis | The CVR map shows steal in R MCA and PCA territories. The z-maps show not only the extent, but also the severity of abnormality. The lowest z-scores correspond to the ‘blue' of the CVR; the z-map confirms that the CVR in the WM on the left side is also diffusely reduced |
| 2 | R TIA presentation. Angiography shows L ICA occlusion | The CVR map shows that steal is present in the entire left hemisphere. The z-maps indicate the severity of the abnormality and the extent of hemodynamic involvement. The CVR in the R hemisphere also appears reduced (Sam et al.44) |
| 3 | TIA. L ICA stenosis | Despite the unilateral vascular lesion, the CVR map is symmetrical, but appears reduced. The z-maps confirm marked reduction in CVR throughout the cortex and deep WM regions |
| 4 | Hx previous stroke. L ICA stenosis | The CVR map appears to be normal except for a mild CVR impairment in the area of the stroke. The z-maps confirm that CVR is normal in the normal-appearing areas of the CVR map; severe reduction of CVR in area of stroke |
| 5 | Stroke in the watershed area extending into the MCA. Stroke in the left subcortical region. Left cavernous ICA occlusion and R ICA stenosis | The CVR map appears to be normal with some reduction in the left subcortical area. The z-maps confirmed the normality of much of the scan but show that the subtle-appearing changes of the CVR map are in fact severely abnormal |
| 6 | Hx astrocytoma of the optic chiasm as a child, Rx with surgical resection, chemotherapy, and radiotherapy. L EC-IC bypass 2 years ago for MM | The CVR map appears to be close to normal but gives an impression that CVR was somewhat diffusely reduced with little visible steal. The z-maps emphasize that there are widespread reductions in CVR and indicate their severity, particularly in the R WM region which was not apparent from the CVR. Note despite the severity of reductions in CVR, the necessary conditions to generate steal were not met (Sobczyk et al.1) |
| 7 | Hx of repeat TIAs | The CVR map shows impaired CVR in the right MCA, which extends to the ACA territory, with the severity difficult to judge; CVR elsewhere appears normal. The z-maps scores the severity and extent of reduced CVR in the area of steal, but shows the extent of impaired CVR exceeds that of steal; confirms normal reactivity in the contralateral hemisphere on the side of the EC-IC bypass |
| 8 | Hx MM with intraventricular hemorrhage | The CVR map shows that CVR is reduced globally, with reduced CVR and possibly some steal evident on the left. The z-maps show that the bilateral CVR impairment in both R and L MCA territories is severe beyond 2 s.d. |
| 9 | Hx MM with infarct. Post-R EC-IC bypass; rescanned for assessment of continuing TIA | The CVR map indicates a persistent reduction of CVR throughout the R MCA region. The z-maps confirm these bilateral reductions in CVR, much worse in the areas of steal |
| 10 | Idiopathic intracranial hypertension | The CVR map shows areas of steal in the WM of the frontal and occipital lobes, with normal-appearing CVR in the rest of the brain. The z-maps, however, confirm bilateral severe reduction in CVR in deep GM and WM, that was not realized from an examination of the CVR map |
ACA, anterior cerebral artery; CVR, cerebrovascular reactivity; EC-IC, external carotid to internal carotid; GM, gray matter; Hx, history; ICA, internal carotid artery; L, left; MCA, middle cerebral artery; MM, Moyamoya; PCA, posterior cerebral artery; R, right; Rx, treatment; s.d., standard deviation; TIA, transient ischemic attack; VA, vertebral artery; WM, white matter.