PURPOSE: To evaluate the utility of FLAIR (Fluid Attenuated Inversion Recovery) MR imaging in cerebral infarction by comparing its results with those of T2-weighted spin-echo imaging. MATERIALS AND METHODS: We retrospectively evaluated fast FLAIR images and conventional spin echo images of 82 patients (47 men and 20 women; median age 60.9 years) with cerebral infarction. MR imaging used a 1.5T MR unit with conventional T2 (TR 3900, TE 90) and fast FLAIR sequence (TR 8000, TE 105, TI 2400). We analysed the size of the main lesion and number of lesions, and discrimination between old and new lesions and between small infarction and perivascular space. RESULTS: When T2-weighted and FLAIR imaging were compared, the latter showed that the main lesion was larger in 38 cases (46%), similar in 38 (46%), and smaller in six (7%). The number of lesions was greater in 23 cases (28%), similar in 52 (63%), and fewer in seven (9%). FLAIR images discriminated between old and new lesions in 31 cases ; perivascular space and small infartion were differentiated in eight cases, and CSF inflowing artifact was observed in 66 (80%). CONCLUSION: In the diagnosis of cerebral infaretion, fast FLAIR provides images that are equal or superior to T2-weighted images. The fast FLAIR sequence may therefore be used as a part of routine MR brain study in the diagnosis of cerebral infarction.