Lacunar infarcts are commonly found in the basal ganglia, though little is known about the organization of small-scale microvascular territories that presumably subtend lacunae. We investigated microvascular territories of the lenticulostriate arteries, the recurrent artery of Heubner, the anterior choroidal artery, and striate branches of the anterior cerebral and anterior communicating arteries in perfusion-fixed human brains by simultaneous injection of fluorescent dyes and a radio-opaque substance in 5% gelatin. Territories were defined by ultraviolet illumination of dye and high-resolution mammography of radio-opaque substance. Brains were sectioned coplanar with the Talairach proportional grid system and vascular data were plotted, allowing for application to any human brain. The data suggest first that the lenticulostriate artery, recurrent artery of Heubner, and anterior choroidal artery supply distinct territories of the basal ganglia with minimal overlap and sparse anastomoses between major penetrating vessels. Individual territories are spatially consistent across brains and match the extent of major/minor infarcts. Second, branching patterns of parental, second-, and third-order vessels leading to circumscribed terminal vascular beds could account structurally for "lacunar" infarcts.

Micro- or macro-circulatory insufficiency has a negative impact in patients with Alzheimer’s disease (AD). This study used arterial spin-labeled magnetic resonance imaging (ASL-MRI) and ethylcysteinate dimer single-photon emission computed tomography (ECD-SPECT) in 50 patients with AD and 30 age-matched controls to investigate how hypoperfusion patterns were associated with gray matter atrophy and clinical data. All participants completed 3DT1-MRI, ECD-SPECT and ASL-MRI examinations. Medial temporal cortex (MTC) volumes were correlated with regional signals showing significantly lower relative cerebral blood flow (rCBF) in ASL-MRI or perfusion index (PI) in ECD-SPECT. Neurobehavioral scores served as the outcome measures. Regions with lower PI showed spatial similarities with atrophy in the medial, anterior and superior temporal lobes, posterior cingulate cortex and angular gyrus, while regions showing lower rCBF were localized to the distal branches of posterior cerebral artery territories (posterior parietal and inferior temporal lobe) and watershed areas (angular gyrus, precuneus, posterior cingulate gyrus and middle frontal cortex). rCBF values in watershed areas correlated with MTC volumes and language composite scores. Precuneus and angular gyrus hypoperfusion were associated with the corresponding cortical atrophy. Macro- or micro-vasculature perfusion integrities and cortical atrophy determined the overall perfusion imaging topography and contributed differently to the clinical outcomes.

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