title: Apparent diffusion coefficient with higher b-value correlates better with viable cell count quantified from the cavity of brain abscess.
abstract: OBJECTIVE
  DWI by using higher b-values provides tissue diffusivity with less T2 shinethrough effect. VCD in the abscess cavity correlates with ADC values. The purpose of this study was to investigate which b-value-derived ADC correlates better with VCD.
  
  
  METHODS
  Thirty patients with brain abscess underwent conventional MR imaging and DWI with b = 1000, 2000, and 3000 s/mm(2) on a 3T MR imaging scanner. ADC values were quantified by placing regions of interest inside the abscess cavity in all sections where the lesion was apparent on coregistered ADC maps derived from different b-values. VCD was measured on pus aspirated.
  
  
  RESULTS
  An increase in b-value was associated with a decrease in ADC values in normal parenchyma as well as in the abscess cavity. The most significant negative correlation of VCD was observed with b = 3000 s/mm(2) (r = -0.98, P = .01).
  
  
  CONCLUSIONS
  VCD in the abscess cavity can be best assessed at b = 3000 s/mm(2) secondary to the reduction in the T2 shinethrough effect. DWI with b = 3000 s/mm(2) is of promising value in the assessment of the therapeutic response of brain abscess.
authors: Department of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors: V
authors: V
authors: Tomar
authors: A
authors: A
authors: Yadav
authors: R K S
authors: RK
authors: Rathore
authors: S
authors: S
authors: Verma
authors: R
authors: R
authors: Awasthi
authors: V
authors: V
authors: Bharadwaj
authors: B K
authors: BK
authors: Ojha
authors: K N
authors: KN
authors: Prasad
authors: R K
authors: RK
authors: Gupta
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001921:Brain / Q000473:pathology*; D001922:Brain Abscess / Q000473:pathology*; D002452:Cell Count / Q000379:methods*; D002470:Cell Survival; D002648:Child; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D055815:Young Adult