title: Comparison of the magnetization transfer ratio and fluid-attenuated inversion recovery imaging signal intensity in differentiation of various cystic intracranial mass lesions and its correlation with biological parameters.
abstract: OBJECTIVE
  To compare the signal intensity on the fluid attenuated inversion recovery (FLAIR) sequence and magnetization transfer ratios (MTRs) for the differentiation of abscesses from non-abscess cystic brain lesions, and to correlate these MR parameters with the viscosity, viable cell density and total protein concentration of the cystic fluid.
  
  
  METHODS
  Signal intensity on FLAIR and MTRs from the cystic cavity of lesions were calculated from 33 patients (brain abscess (N = 12) and non-abscess (N = 21)). The fluid from the lesion was aspirated at the time of surgery, and the viscosity, viable cell density, and total protein concentration were measured.
  
  
  RESULTS
  Signal intensity on FLAIR correlated significantly with the total protein concentration in abscess (r = 0.60, P < 0.05) and non-abscess lesions (r = 0.41, P < 0.05). However, there was no significant difference (P > 0.05) in the FLAIR signal intensity of the abscess (318.8 +/- 75) and non-abscess group (258 +/- 47). The MTR of the brain abscesses (13 +/- 0.95) was significantly higher (P < 0.05) than that of the non-abscess group (3.5 +/- 0.3). A significant correlation was observed between MTR and viscosity (r = 0.75, P < 0.05), total protein concentration (r = 0.60, P < 0.05), and cell density (r = 0.70, P < 0.05) in brain abscess, and viscosity (r = 0.81, P < 0.05) and total protein concentration (r = 0.41, P < 0.05) in non-abscess lesions.
  
  
  CONCLUSIONS
  It is possible to differentiate brain abscesses from non-abscess cystic lesions using MT imaging. The MTR correlates significantly with the viscosity, viable cell density, and total protein concentration in brain abscess, and with viscosity and total protein concentration in non-abscess lesions. FLAIR signal intensity correlates significantly only with the total protein concentration in abscess and non-abscess lesions.
authors.affiliation: Department of Radiodiagnosis, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Asht M
authors.initials: AM
authors.lastname: Mishra
authors.forename: Sangala J
authors.initials: SJ
authors.lastname: Reddy
authors.forename: Mazhar
authors.initials: M
authors.lastname: Husain
authors.forename: Sanjay
authors.initials: S
authors.lastname: Behari
authors.forename: Nuzhat
authors.initials: N
authors.lastname: Husain
authors.forename: Kashi N
authors.initials: KN
authors.lastname: Prasad
authors.forename: Sunil
authors.initials: S
authors.lastname: Kumar
authors.forename: Rakesh K
authors.initials: RK
authors.lastname: Gupta
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001922:Brain Abscess / Q000473:pathology*; D001927:Brain Diseases / Q000175:diagnosis* / Q000473:pathology; D001930:Brain Injuries / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged