system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Aged, Aged, 80 and over, Cerebral Infarction, Cerebrovascular Circulation, Diffusion Magnetic Resonance Imaging, Disease Progression, Female, Humans, Ischemic Attack, Transient, Male, Middle Aged, Predictive Value of Tests, Prospective Studies, Risk Assessment, Risk Factors, Stroke, Time Factors.
user
Does normal magnetic resonance perfusion-weighted imaging in lacunar infarcts predict a low risk of early deterioration? Context: Current clinical tools to identify lacunar infarct patients at risk of deterioration are inadequate, and imaging techniques to predict fluctuation and deterioration would be of value. We sought to determine the occurrence of MRI perfusion-weighted imaging (PWI) abnormalities in lacunes, and whether they help predict clinical and radiological outcome. Patients with lacunar stroke or TIA were selected from a prospective MR imaging study. MRI was performed within 24 h of the event and follow-up imaging completed at 30 or 90 days. Baseline perfusion maps were qualitatively assessed and infarct volumes measured. Early clinical deterioration (NIHSS worsening of > or = 3 points within 72 h of event) and 90-day modified Rankin Scale score (mRS) were recorded. Twenty-two patients were included. Fifteen (68.2%) had abnormal PWI at the site of the diffusion-weighted imaging lesion. Patients with abnormal PWI were more likely to have stroke than TIA as their index event (RR 2.2, 95% CI 0.9-5.2, p = 0.02). Early clinical deterioration occurred in 4 patients (18.2%), all of whom had abnormal PWI. PWI lesions were not associated with a higher 90-day NIHSS or mRS score, nor did they predict infarct volume growth.
assistant
MR-PWI abnormalities are seen in two thirds of lacunar infarcts, and are associated with stroke rather than TIA. Normal PWI identifies patients at low risk of early clinical deterioration. Final Decision: yes