Chronic brain changes including WMCs, MTLA, and AD pathology are associated with incident dementia after stroke/TIA. Interventions targeting these chronic brain changes may reduce burden of vascular cognitive impairment.

C ognitive impairment in the context of stroke or transient ischemic attack (TIA) is a prototype of vascular cognitive impairment (VCI). Our recent in vivo study using carbon-11-labeled Pittsburgh compound B ( 11 C-PiB) positron emission tomography (PET) found that ≈30% of subjects with poststroke/TIA cognitive impairment harbored Alzheimer's pathology.1 Although some studies suggested that in patients with clinical Alzheimer's disease (AD), comorbid cerebrovascular disease was associated with a more rapid cognitive decline, 2,3 it is still unknown whether concurrent presence of Alzheimer's pathology is associated with a faster cognitive deterioration in patients with poststroke/TIA cognitive impairment.In this study, we compared the longitudinal cognitive changes between VCI patients with and without AD-like amyloid-beta (Aβ) deposition measured using 11 C-PiB PET. We hypothesized that over 3 years, PiB-positive VCI (mixed VCI [mVCI]) subjects would experience a more rapid and continuous course of cognitive deterioration, resulting in more severe cognitive impairment than those who were PiB-negative (pure VCI [pVCI]). Methods SubjectsSubjects of this study were participants of the ongoing Stroke Registry Investigating cognitive Decline (STRIDE) study. 1 In the Background and Purpose-We hypothesized that comorbid amyloid-beta (Aβ) deposition played a key role in long-term cognitive decline in subjects with stroke/transient ischemic attack. Methods-We recruited 72 subjects with cognitive impairment after stroke/transient ischemic attack to receive Carbon-11-labeled Pittsburgh compound B positron emission tomography. We excluded subjects with known clinical Alzheimer's disease. Those with and without Alzheimer's disease-like Aβ deposition were classified as mixed vascular cognitive impairment (mVCI, n=14) and pure VCI (pVCI, n=58), respectively. We performed Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment to evaluate global cognition and cognitive domains (memory, visuospatial function, language, attention, and executive function) at 3 to 6 months (baseline) and annually for 3 years after the index event. We compared cognitive changes between mVCI and pVCI using linear mixed models and analysis of covariance adjusted for age and education. Results-Over 3 years, there were significant differences between mVCI and pVCI on change of MMSE score over time (group×time interaction, P=0.007). We observed a significant decline on MMSE score (P=0.020) in the mVCI group but not in the pVCI group (P=0.208 6 were performed on subjects at 3 to 6 months (baseline) after the index event to index general cognition. Then subjects were further invited to return for annual follow-up. This study analyzed the data collected ≤3 years.This substudy included a sample of 72 subjects with cognitive impairment (CDR grade ≥0.5) from the STRIDE study. Clinical diagnoses were made by 2 neurologists specialized in dementia (V.C.T.M. and L.A.). Thirty-six subjects had CDR grade of ≥1 and met the criteria for dementia acco...

The success of liver transplantation (LT) for hepatocellular carcinoma (HCC) is enhanced by careful patient selection on the basis of the Milan criteria. The criteria are traditionally assessed by contrast CT, which is known to be affected by structural or architectural changes in cirrhotic livers. We aimed to compare dual-tracer ( 11 C-acetate and 18 F-FDG) PET/CT with contrast CT for patient selection on the basis of the Milan criteria. Methods: Patients who had HCC and had undergone both preoperative dual-tracer PET/CT and contrast CT within a 1-mo interval were retrospectively studied. They then underwent either LT (n 5 22) or partial hepatectomy (PH) (n 5 21; HCC of # 8 cm). Imaging data were compared with data from postoperative pathologic analysis for accuracy in assessment of parameters specified by the Milan criteria (tumor size and extent, vascular invasion, and metastasis), TNM staging, and patient selection for LT. Results: Dual-tracer PET/CT performed equally well in both LT and PH groups for HCC detection (94.1% vs. 95.8%) and TNM staging (90.9% vs. 90.5%). Contrast CT performed reasonably well in the LT group but not in the PH group for HCC detection (67.6% vs. 37.5%) and TNM staging (54.5% vs. 28.6%). In the LT group, the sensitivity and specificity of contrast CT for patient selection on the basis of the Milan criteria were 43.8% and 66.7%, respectively (comparable to values in the literature); the sensitivity and specificity of dual-tracer PET/CT were 93.8% and 100%, respectively (both Ps , 0.05). From the surgeon's perspective, we tended to perform transplantation for patients with higher diagnostic certainty (stricter CT criteria) because of a shortage of donor grafts. Patients who were not transplant candidates usually underwent up-front hepatectomy without the benefit of reassessment contrast CT, resulting in lower accuracies for the PH group. The overall sensitivity (96.8%) and specificity (91.7%) of dual-tracer PET/CT for patient selection for LT were significantly higher than those of contrast CT (41.9% and 33.0%, respectively) (both Ps , 0.05). Sources of error for contrast CT were related to cirrhosis or previous treatment and included difficulty in differentiating cirrhotic nodules from HCC (39%) and estimation of tumor size (14%). Overstaging of vascular invasion (4.6%) and extrahepatic metastases (4.6%) was infrequent. The rate of false-negative results of dual-tracer PET/CT was 4.7%. Conclusion: Dual-tracer PET/CT was significantly less affected by cirrhotic changes than contrast CT for HCC staging and patient selection for LT on the basis of the Milan criteria. The inclusion of dual-tracer PET/CT in pretransplant workup may warrant serious consideration.