CCURATE localization of superficial lesions adjacent to the central sulcus is essential for preoperative di- agnostic imaging and surgical planning. The prereq- uisite is the presentation of the brain surface in a manner that allows reliable identification of the central sulcus with adjacent eloquent areas. Standard MR imaging in three or- thogonal 2D planes is often sufficient for anatomical identi- fication of sulci and gyri. 15–17 Nevertheless, problems may occur due to tumor-associated distortions of the anatomy or anatomical variations of the brain surface. Furthermore, it may be impossible to determine the complete localization of large tumors and their relationships to the motor area. To overcome these limitations, fMR imaging and complex sur- face-rendering algorithms can be used to provide more pre- cise mapping of eloquent areas. 4–7,14,18–20 These methods are often time consuming, however, and demand dedicated computer systems and the operator’s expertise. A novel way of brain-surface reconstruction is BSR imaging. This tech- nically quick and easy postprocessing method opens the en- tire central sulcus of both hemispheres into a flat plane. 9 The frontoparietal surface relief is displayed as a map with a mirror image–like overview of both hemispheres. In this preliminary study we evaluated whether this new form of surface representation is a suitable tool for the accurate de- piction of superficial brain lesions and their relation to the central sulcus and adjacent pre- and postcentral gyri. Clinical Material and Methods Patient Population Twenty-seven patients with brain lesions in the vicinity of the central sulcus were examined preoperatively with MR imaging on a 1.5-tesla system (Gyroscan Intera; Philips Medical Systems, Best, The Netherlands). Informed con- sent was obtained from all patients. The standard proto- col included axial, coronal, and sagittal imaging with T 1 - and T 2 -weighted sequences. All patients also underwent J Neurosurg 102:302–310, 2005 302 Brain surface reformatted images for fast and easy localization of perirolandic lesions ELKE HATTINGEN, M.D., CATRIONA GOOD, M.D., STEFAN WEIDAUER, M.D., SEBASTIAN HERMINGHAUS, M.D., PETER RAAB, M.D., GERHARD MARQUARDT , M.D., ANDREAS RAABE, M.D., PH.D., VOLKER SEIFERT , M.D., PH.D., AND FRIEDHELM E. ZANELLA, M.D., PH.D Institute of Neuroradiology, Department of Neurosurgery, Johann Wolfgang Goethe University, Frankfurt am Main; and Department of Radiology, Johannes Gutenberg–University Mainz, Germany Object. The goal of this study was to evaluate a novel form of brain surface representation that allows simple, reliable mapping of the surface neuroanatomy for the preoperative evaluation of the spatial relationship between a focal lesion and the precentral gyrus. Methods. High-resolution three-dimensional (3D) magnetic resonance (MR) imaging data sets were postprocessed us- ing a curved multiplanar reformatting technique to create brain surface reformatted (BSR) images. These BSR images were reconstructed in less than 5 minutes and demonstrated the entire central sulcus with adjacent surface structures in one view. Two experienced neuroradiologists determined the localization of lesions near the central sulcus in 27 patients on standard MR images in three orthogonal planes and on BSR images. In addition, these observers judged whether the lesions were easy or difficult to localize on standard MR and BSR images, and whether diagnoses based on these methods were certain or doubtful. Anatomical localization based on BSR images was compared with that based on functional MR (fMR) images or intraoperative mapping of motor function. The BSR images yielded a perfect concordance with the fMR images and in- traoperative mapping (Cohen  1.0) and optimal diagnostic accuracy in localizing perirolandic lesions (both sensitivity and specificity were 100%). Localization was judged to be easy for 48 of 54 diagnoses based on BSR images compared with 26 of 54 based on standard MR images. Diagnoses were assessed as certain for 52 cases based on BSR images and 34 cas- es based on standard MR images. Conclusions. Brain surface reformatted imaging improves the diagnostic accuracy of standard anatomical MR imaging for localizing superficial brain lesions in relation to the precentral gyrus. The complementary use of this technique with standard two-dimensional imaging is supported by the fast and simple postprocessing technique and may provide useful information for preoperative surgical planning. KEY WORDS • magnetic resonance imaging • brain surface • curved multiplanar reformatting • precentral gyrus • perirolandic lesion A J. Neurosurg. / Volume 102 / February, 2005 Abbreviations used in this paper: BSR = brain surface reformatted; CMPR = curved multiplanar reformatting; fMR = functional magnetic resonance; 2D = two-dimensional; 3D = three-dimensional.