PURPOSE: To compare periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) multishot fast spin-echo diffusion-weighted magnetic resonance (MR) imaging with single-shot echo-planar diffusion-weighted MR imaging for image quality and visualization of acute cerebral infarction. MATERIALS AND METHODS: Seventy subjects (35 men, 35 women; mean age, 55 years 24 [SD]) who were suspected of having acute cerebral infarction (symptom duration, 2.8 days :2.7) underwent PROPELLER and echo-planar MR imaging (b = 1,000 sec/mm(2)). Two neuroradiologists compared unlabeled images for presence of artifacts, visualization of infarction, and their preference of images. Interobserver agreement and image comparison were assessed by using the K statistic and the x(2) test, respectively. RESULTS: PROPELLER MR imaging reduced susceptibility artifacts (n = 70 subjects), limited visualization of temporal (echo-planar, n = 64; PROPELLER, n = 0; P < which 2.01, X test), frontal (echo-planar, n = 58; PROPELLER, n = 1; P <.01), and parietal n = 5; PROPELLER, n = 0; P <.05) and cerebellum (echo-planar, lobes (echo-planar, n = 0; P <.01) and brainstem (echo-planar, n = 23; n = 36; PROPELLER, PROPELLER, n = 0;,P <.01). Acute infarction (n = 31 subjects) was better demonstrated at PROPELLER MR imaging (PROPELLER better, n = 18; echo-planar better, n = 1; PROPELLER and echo-planar equal, n = 12; P <.01, x(2) test). PROPELLER MR imaging was preferred in all (n = 70) but one case in which the lesion lay within the intersection gap (PROPELLER preferred, n = 69; echo-planar preferred, n = 1; P <.01, x(2) test). CONCLUSION: With a short increase in imaging time, PROPELLER MR imaging offers better image quality and detection of acute cerebral infarction than does echo-planar MR imaging. (C) RSNA, 2002.