title: Correlation between anatomic landmarks and fMRI in detection of the sensorimotor cortex in patients with structural lesions.
abstract: BACKGROUND
  Structural lesions in/near the sensorimotor cortex may cause distortion/obscuration of the anatomic landmarks.
  
  
  OBJECTIVE
  To compare the localization of the sensorimotor cortex using anatomical landmarks and fMRI in the clinical setting in patients with structural lesions in/near the central sulcus.
  
  
  METHODS
  We analyzed the anatomic and fMRI data of 68 consecutive patients (42 tumors, 15 gliotic lesions, 11 focal cortical dysplasias [FCD]) who underwent MRI to assess the relationship of these lesions to the sensorimotor cortex. Anatomical data was analyzed on conventional two- and three-dimensional sequences. BOLD fMRI was performed with block design hand/leg or lip movement paradigm and general linear model was used for detecting the activated cortex. fMRI was considered as a valid method for identifying the sensorimotor cortex based on previously reported literature.
  
  
  RESULTS
  The sensorimotor cortex could not be identified with anatomical landmarks in 9/68 (13.2%) patients. fMRI detected activation in areas different from that predicted by anatomical landmarks in 11/68 (16.2%) cases. This occurred in 5/42 (11.9%) tumors, 6/15 (40%) gliotic lesions, and 0/11 (0%) FCDs. The kappa value for concordance between fMRI and anatomic landmarks was 0.883 overall, 1.0 for tumors, 0.721 for gliotic lesions, and in none of the patients with focal cortical dysplasias.
  
  
  CONCLUSIONS
  In patients with lesions that obscure normal cerebral landmarks, fMRI supplies the information that is not available from the anatomic images. In patients with landmarks that can be recognized, the location of the rolandic cortex may be misjudged in some cases if functional imaging is not used. Anatomic landmarks may not correlate with the area of functional activation in gliotic lesions and tumors. Determining the risk of a postoperative neurologic defect from surgery is likely to be more reliable with functional imaging than with conventional anatomic imaging.
authors.affiliation: Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, India.
authors.forename: Divyata
authors.initials: D
authors.lastname: Hingwala
authors.forename: Bejoy
authors.initials: B
authors.lastname: Thomas
authors.forename: Ashalatha
authors.initials: A
authors.lastname: Radhakrishnan
authors.forename: N
authors.initials: N
authors.lastname: Suresh Nair
authors.forename: C
authors.initials: C
authors.lastname: Kesavadas
mesh_terms: D000293:Adolescent; D000328:Adult; D001927:Brain Diseases / Q000175:diagnosis* / Q000473:pathology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology*; D012189:Retrospective Studies; D013003:Somatosensory Cortex / Q000473:pathology*
keywords: anatomical landmarks; fMRI; focal cortical dysplasia; gliosis; sensorimotor cortex; tumors