title: Post-concussion syndrome: Correlation of neuropsychological deficits, structural lesions on magnetic resonance imaging and symptoms.
abstract: BACKGROUND
  Post-concussion syndrome (PCS) associated with mild traumatic brain injury (MTBI) can cause long-lasting disabilities. Magnetic resonance imaging (MRI) evaluation in these patients may demonstrate structural lesions that correlate with functional deficits on neuropsychological testing. However, little is known about the significance of the relationship between structural lesions on MRI, functional deficits on neuropsychological evaluation and outcome in patients with MTBI.
  
  
  OBJECTIVE
  To assess neuropsychological deficits and structural lesions on MRI in patients with PCS following MTBI, and to find correlation between these findings and PCS.
  
  
  METHODS
  Prospective, observational, cohort study in a tertiary hospital.
  
  
  METHODS
  The study cohort included consecutive patients with MTBI (three months or more duration) and PCS. All the patients in the cohort had neuropsychological testing using the National Institute of Mental Health and Neurological Sciences Neuropsychological Battery for head injury and also MRI using T1, T2 and FLAIR sequences. Statistical analysis was done using Fisher's Exact test of significance.
  
  
  RESULTS
  All the 20 patients evaluated had neuropsychological deficits. Eleven patients had lesions on MRI. Disturbances of sleep, behavior and memory and abnormalities in tests for mental speed were more frequent in patients with lesions on MRI, but were not statically significant (P = 0.08). Both the test modalities localized lesions predominantly to the frontal and temporal lobes. All the symptoms observed in the patients were associated with prefrontal dysfunction on neuropsychological testing.
  
  
  CONCLUSIONS
  Prefrontal dysfunction is invariably associated with PCS following MTBI. Structural lesions on MRI may not always be present but when present may influence the degree or severity of the symptoms.
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: S G S
authors.initials: SG
authors.lastname: Datta
authors.forename: Shibu V
authors.initials: SV
authors.lastname: Pillai
authors.forename: S L
authors.initials: SL
authors.lastname: Rao
authors.forename: J M E
authors.initials: JM
authors.lastname: Kovoor
authors.forename: B A
authors.initials: BA
authors.lastname: Chandramouli
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology*; D015331:Cohort Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D019370:Observation; D038223:Post-Concussion Syndrome / Q000150:complications* / Q000473:pathology; D012720:Severity of Illness Index; D013223:Statistics as Topic; D055815:Young Adult