title: Three‑time point view of mild brain injuries' structural alteration and their association with cognitive domains.
abstract: BACKGROUND
  Mild traumatic brain injury (mTBI) accounts for 70‑80% of total neurotrauma, majority among them manifest with cognitive deficits. Till date there are few/or no 3‑time‑point longitudinal studies that have evidenced brain volume changes. The current study has investigated volume changes at 3‑time‑points and their association with cognitive sequel.
  
  
  METHODS
  Twenty‑one mTBI patients with normal imaging and 15 GCS were recruited. Initially these patients were evaluated with magnetic resonance imaging (MRI) scan ≤36hours and neuropsychological test (NPT) during 2‑3weeks after‑injury. All the patients were available for follow‑up for repeat MRI and NPT on 3‑4 and 6‑7months. The imaging and test scores were analyzed using repeated measures of analysis (P<0.05). The brain volumes were correlated with respective test‑scores using partial‑correlation.
  
  
  RESULTS
  Left frontal lobe (P<0.029) and thalamus (P=0.049) showed significant increase in mean volume overtime, whereas corpus callosum (mid‑anterior [P=0.011] and central [P=0.04]) and left cerebellum (P=0.043) showed significant decrease in mean volume overtime. Clinically cognitive scores improved with time. Eventual improvements in attention and memory scores were positively associated with increase in cingulate gyrus volume.
  
  
  CONCLUSIONS
  The 3‑time‑point longitudinal study illustrates brain areas that changes with time and their association with improving cognitive scores. The study provides hint about the pattern of natural recovery.
authors.affiliation: National Institute of Epidemiology (ICMR), Chennai, India.
authors.forename: Ashok
authors.initials: A
authors.lastname: Munivenkatappa
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, India - drindiradb@gmail.com.
authors.forename: Bhagavatula
authors.initials: B
authors.lastname: Indira Devi
authors.affiliation: Department of Neurosurgery, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Dhaval P
authors.initials: DP
authors.lastname: Shukla
authors.affiliation: Department of Clinical Psychology, National Institute of Mental Health and Neurosciences, Bangalore, India.
authors.forename: Jamuna
authors.initials: J
authors.lastname: Rajeswaran
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology* / Q000601:surgery; D001924:Brain Concussion / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D001930:Brain Injuries / Q000175:diagnosis / Q000473:pathology*; D003071:Cognition / Q000502:physiology; D060825:Cognitive Dysfunction / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D009483:Neuropsychological Tests