title: Correlation of quantitative diffusion tensor tractography with clinical grades of subacute sclerosing panencephalitis.
abstract: OBJECTIVE
  SSPE is a persistent infection of the central nervous system caused by the measles virus. The correlation between the clinical staging and conventional MR imaging is usually poor. The purpose of this study was to determine whether tract-specific DTI measures in the major white mater tracts correlate with clinical grades as defined by the Jabbour classification for SSPE.
  
  
  METHODS
  Quantitative DTT was performed on 20 patients with SSPE (mean age, 9 years) and 14 age- and sex-matched controls. All patients were graded on the basis of the Jabbour classification into grade II (n=9), grade III (n=6), and grade IV (n=5) SSPE. The major white matter tracts quantified included the CC, SLF, ILF, CST, CNG, SCP, MCP, ICP, ATR, STR, and PTR.
  
  
  RESULTS
  Although a successive decrease in mean FA values was observed in all the fiber tracts except for the SCP and ICP, moving from controls to grade IV, a significant inverse correlation between clinical grade and mean FA values was observed only in the splenium (r=-0.908, P<.001), CST (r=-0.663, P=.013), SLF (r=-0.533, P=.050), ILF (r=-0.776, P=.001), STR (r=-0.538, P=.047), and PTR (r=-0.686, P=.035) fibers. No significant correlation of mean MD values from these white matter tracts was observed with clinical grades of the disease.
  
  
  CONCLUSIONS
  We conclude that the grade of encephalopathy correlates inversely with the tract-specific mean FA values. This information may be valuable in studying the disease progression with time and in assessing the therapeutic response in the future.
authors.affiliation: Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: R
authors.initials: R
authors.lastname: Trivedi
authors.forename: H
authors.initials: H
authors.lastname: Anuradha
authors.forename: A
authors.initials: A
authors.lastname: Agarwal
authors.forename: R K S
authors.initials: RK
authors.lastname: Rathore
authors.forename: K N
authors.initials: KN
authors.lastname: Prasad
authors.forename: R P
authors.initials: RP
authors.lastname: Tripathi
authors.forename: R K
authors.initials: RK
authors.lastname: Gupta
mesh_terms: D002648:Child; D056324:Diffusion Tensor Imaging / Q000379:methods* / Q000592:standards; D018450:Disease Progression; D005260:Female; D006801:Humans; D056784:Leukoencephalopathies / Q000145:classification / Q000473:pathology; D008297:Male; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013344:Subacute Sclerosing Panencephalitis / Q000145:classification* / Q000473:pathology*