Positron Emission Tomographic Imaging in Stroke Cross-Sectional and Follow-Up Assessment of Amyloid in Ischemic Stroke

• Background and Purpose Cardiovascular risk factors significantly increase the risk of developing Alzheimer disease. A possible mechanism may be via ischemic infarction-driving amyloid deposition. We conducted a study to determine the presence of -amyloid in infarct, peri-infarct, and hemispheric areas after stroke. We hypothesized that an infarct would trigger -amyloid deposition, with deposition over time. Methods Patients were recruited within 40 days of acute ischemic stroke and imaged with computed tomographic or magnetic resonance imaging and Pittsburgh compound B (11C-PiB) positron emission tomographic scans. Follow-up positron emission tomographic scanning was performed in a subgroup 18 months after the stroke event. Standardized uptake value ratios for regions of interest were analyzed after coregistration. Results Forty-seven patients were imaged with C-11-PiB positron emission tomography. There was an increase in C-11-PiB accumulation in the stroke area compared with a reference region in the contralesional hemisphere, which was not statistically significant (median difference in standardized uptake value ratio, 0.07 [95% confidence interval, -0.06 to 0.123]; P=0.452). There was no significant increase in the accumulation of C-11-PiB in the peri-infarct region or in the ipsilesional hemisphere (median difference in standardized uptake value ratio, 0.04 [95% confidence interval, -0.02 to 0.10]; P=0.095). We repeated C-11-PiB positron emission tomography in 21 patients and found a significant reduction in accumulation of C-11-PiB between regions of interest (median difference in standardized uptake value ratio, -0.08 [95% confidence interval, -0.23 to -0.03]; P=0.04). Conclusions There was no significant increase in C-11-PiB accumulation in or around the infarct. There was no increase in ipsilesional hemispheric C-11-PiB accumulation over time. We found no evidence that infarction leads to sustained or increased -amyloid deposition 18 months after stroke.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Neurovetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Neurosciences (hsv//eng)

Nyckelord

Alzheimer disease

follow-up studies

positron emission tomography

risk factors

pittsburgh compound-b

vascular risk-factors

alzheimers-disease

cerebrovascular-disease

a-beta

dementia

brain

deposition

hemorrhage

cognition

Neurosciences & Neurology

Cardiovascular System & Cardiology

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)