Objective: It has recently been described that perirolandic cortex generally had a low signal intensity (SI) in neurologically normal brain. The aim of this study was to confirm this finding by an objective quantitative study. Materials and methods: Turbo fluid attenuated inversion recovery (FLAIR) magnetic resonance (MR) images of 24 neurologically normal patients were evaluated retrospectively. Signal intensity measurements of the precentral and superior frontal cortices (SFCs) were obtained at a manually traced irregular region-of-interest (ROI). t-Test for paired samples was used to evaluate the significance of differences between signal intensity measurements. Results: Mean signal intensities of precentral and superior frontal cortices were 349.5 and 380.7, respectively, on the right, and 351.7 and 374.1 on the left hemisphere. The difference between the mean signal intensities of the side-matched precentral and superior frontal cortices was statistically significant (P < 0.001). Conclusion: Low signal intensity of the precentral cortex (PCC) in normal brain on turbo FLAIR images is an objective finding, confirmed by ROI measurement. (C) 2004 Elsevier Ireland Ltd. All rights reserved.