title: Temporal lobe anatomy: eight imaging signs to facilitate interpretation of MRI.
abstract: OBJECTIVE
  The temporal lobe is anatomically and functionally complex. However, relatively few radiologic signs are described to facilitate recognition of temporal lobe sulci and gyri in clinical practice. We devised and tested 8 radiologic signs of temporal lobe anatomy.
  
  
  METHODS
  Images from volumetric magnetization-prepared rapid gradient-echo imaging were analyzed of 100 temporal lobes from 26 female and 24 male patients. Patient age ranged from 1 to 79 years (mean 19 years; standard deviation 16 years). Standardized axial, coronal, and sagittal planes were evaluated and cross-referenced. Eight signs to delineate the superior temporal gyrus, Heschl gyrus (HG), parahippocampal gyrus, rhinal sulcus, collateral sulcus proper, or the occipitotemporal sulcus, or a combination, were evaluated in the sagittal or axial plane. Two neuroradiologists independently evaluated each sign; the sign was considered present only with positive reader agreement.
  
  
  RESULTS
  All 8 signs were present in most patients. The most frequent signs were the posterior insular corner to identify HG in the axial plane (100 %), pointed STG to identify STG in the axial plane (98 %), and parahippocampal Y to identify the posterior parahippocampal gyrus in the sagittal plane (98 %). The frequencies were similar between the right and left cerebral hemispheres.
  
  
  CONCLUSIONS
  Temporal lobe gyri and sulci can be reliably identified in multiple planes using anatomic signs.
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA. lehman.vance@mayo.edu.
authors.forename: Vance T
authors.initials: VT
authors.lastname: Lehman
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.
authors.forename: David F
authors.initials: DF
authors.lastname: Black
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.
authors.forename: Matt A
authors.initials: MA
authors.lastname: Bernstein
authors.affiliation: Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.
authors.forename: Kirk M
authors.initials: KM
authors.lastname: Welker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: Collateral sulcus; Fusiform gyrus; Heschl gyrus; Lateral occipitotemporal gyrus; Occipitotemporal sulcus; Parahippocampal gyrus