title: Histological-MRI correlation in the primary motor cortex of patients with amyotrophic lateral sclerosis.
abstract: OBJECTIVE
  To establish the relationship between ALS histopathology and quantitative MRI metrics.
  
  
  METHODS
  ALS patients (N = 8) in advanced stages of the disease were enrolled and, immediately after death, the brain of each patient was removed. Freshly excised ALS tissue was imaged at 3.0 Tesla with T1 and T2 mapping protocols and subsequently stained with astrocyte, myelin, and neuronal markers. Measures of ALS histological stains were compared with the internal control (primary visual cortex) and longitudinal parametric maps.
  
  
  RESULTS
  Post-mortem T1 -weighted images demonstrate diminished contrast between gray and white matter and alterations in T1 relaxation within the primary motor cortex. An increase in astrocyte number and reactivity as well as evident neuronal loss, a decrease in axonal density, and unraveling of the myelin sheaths in subcortical white matter were found in the ALS primary motor cortex exhibiting significant T1 relaxation and contrast changes.
  
  
  CONCLUSIONS
  This study provides a histopathological basis for differences in MR T1 contrast and relaxation seen in the ALS brain.
authors.affiliation: Department of Neurosurgery, The Pennsylvania State University - College of Medicine, Milton S. Hershey Medical Center, Hershey, Pennsylvania, USA; Department of Radiology (Center for NMR Research), The Pennsylvania State University - College of Medicine, Milton S. Hershey Medical Center, Hershey, Pennsylvania, USA.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Meadowcroft
authors.forename: Nathan J
authors.initials: NJ
authors.lastname: Mutic
authors.forename: Don C
authors.initials: DC
authors.lastname: Bigler
authors.forename: Jian-Li
authors.initials: JL
authors.lastname: Wang
authors.forename: Zachary
authors.initials: Z
authors.lastname: Simmons
authors.forename: James R
authors.initials: JR
authors.lastname: Connor
authors.forename: Qing X
authors.initials: QX
authors.lastname: Yang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology*; D002102:Cadaver; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology* / Q000648:ultrastructure
keywords: ALS; MRI; T1; amyotrophic lateral sclerosis; histology; longitudinal relaxation; magnetic resonance imaging