Crossed cerebellar hypoperfusion in hyperacute ischemic stroke.
Level 4 - case-series / case-control
Observational case-control / comparative cross-sectional imaging study
PubMed 15465087 · doi:10.1016/j.jns.2004.07.004
What was done
Single-photon emission computed tomography (SPECT) was performed in 21 patients with middle cerebral artery (MCA) embolic infarction within 6 hours of onset (mean 3.2 ± 1.1 hours). Symmetrical regions of interest were placed across cerebral cortical and subcortical areas and the cerebellar hemispheres to measure regional blood flow ratios, which were compared with normal controls.
What was found
The ratio of ipsilateral to contralateral cerebellar blood flow was significantly higher than in normal controls (P < 0.001), indicating depressed contralateral cerebellar perfusion. Cerebellar blood flow asymmetry correlated with cerebral blood flow ratios in the whole hemispheres (r = 0.44, P < 0.05), anterior frontal lobe (r = 0.44, P < 0.05), and anterior temporal lobe (r = 0.58, P < 0.01), but not in infarct areas (r = 0.26, P = 0.3). Stepwise regression analysis identified anterior temporal lobe hypoperfusion as the primary factor associated with cerebellar asymmetry (multiple regression analysis, r = 0.58, P < 0.01).
Why it matters
This study demonstrates that crossed cerebellar diaschisis is present in the hyperacute phase of stroke (within 6 hours) before conventional CT typically identifies infarction, and suggests it is related to remote anterior temporal and frontal hypoperfusion.
Limits
The sample size was small (21 patients), and the abstract does not report the number or characteristics of the normal controls. The study only included MCA embolic strokes and evaluated cross-sectional imaging without long-term clinical outcome correlation.
Cited by
- supports Damage to the left frontal lobe turns off or suppresses activity in the right cerebellum due to cross-cerebellar diaschisis.