Table 4.

Spontaneous cerebral microembolization and paradoxical embolization via right–left shunts.

Reference	Aim of study	Type of study	n MCI	n AD	n VD	n Controls	Parameters	Outcome
Purandare et al. (2005)	Spontaneous cerebral microemboli, v-a circulation shunts and carotid artery disease in dementia and controls	Cross-sectional		24	17	16	Spontaneus cerebral emboli in MCAs, bubbles in MCAs, PSV in ICA	More cerebral microemboli in VD than controls, in AD not significant, no difference in shunt or carotid stenosis between dementia and controls
Purandare et al. (2006)	Spontaneous cerebral microemboli, v-a circulation shunts and carotid artery disease in dementia and controls	Cross-sectional		85	85	150	Spontaneus cerebral emboli in MCAs, bubbles in MCAs, PSV in ICA	More cerebral microemboli in VD and AD than controls, no difference in shunt or carotid stenosis between dementia and controls
Purandare and Burns (2009)	Association of spontaneous cerebral microembolization with dementia etiology, dementia progression and depression in dementia or controls	Cross-sectional Longitudinal		85	85	150	Spontaneus cerebral emboli in MCAs, bubbles in MCAs, PSV in ICA. Neuropsychological tests in time 0 and 6 months	More cerebral microemboli in AD and VD than controls, more in depression (both dementia and controls). Association with more rapid cognitive decline in dementia

AD, Alzheimer’s disease; ICA, internal carotid artery; MCA, middle cerebral artery; MCI, mild cognitive impairment; PSV, peak systolic velocity; v-a, venous-to-arterial; VD, vascular dementia.