More articles from Brain
- Apolipoprotein E ε4 Does Not Modulate Amyloid-β–Associated Neurodegeneration in Preclinical Alzheimer Disease
These authors investigated the relationship between amyloid-β, phosphorylated tau, and apolipoprotein E in preclinical Alzheimer disease in 170 patients and controls who had serial imaging up to 3.5 years after the initial study. Global volumes as well as volumes in brain regions known to be involved in the chronic stages of the disease were assessed. Their results led them to propose that atrophy rates are primarily influenced by apolipoprotein E via amyloid-β mechanisms and that amyloid-β -associated neurodegeneration occurs only in the presence of phosphorylated tau.
- Blood-Brain Barrier Disruption after Cardiac Surgery
To shed light on brain complications occurring after heart surgery, the authors assessed BBB disruption and DWI findings in half of their patients by imaging at 24 hours after surgery and 24–48 hours later. Additionally, postcontrast T1 images were obtained postoperatively at 2–4 days in the other half of the patients. Almost half the patients undergoing cardiac surgery had evidence of BBB abnormalities and three-quarters showed acute lesions on DWI after surgery. BBB disruption is more prevalent in the first 24 hours after surgery. These findings suggest that MR can be used as an imaging biomarker to assess therapies that may protect the BBB in patients undergoing heart surgery.
- Evaluating CT Perfusion Using Outcome Measures of Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage
Ninety-six patients with SAH were evaluated with CT perfusion for cortical deficits and these were correlated with primary (permanent neurologic deficits and infarctions) and secondary (delayed cerebral ischemia manifesting as clinical deterioration) outcome measures. One-third of patients developed permanent neurologic deficits (78% showed CT perfusion defects), infarctions developed in 18% (88% had perfusion defects), and delayed cerebral ischemia was found in 50% (81% had perfusion defects). The most common perfusion abnormalities were reduced CBF and prolonged MTT.