title: Feasibility of tissue similarity map-based relative cerebral blood volume assessment in the evaluation of gliomas.
abstract: OBJECTIVE
  To investigate the feasibility of tissue similarity map (TSM)-based relative cerebral blood volume (rCBV) assessment in evaluating the hemodynamic characteristics of gliomas and in differentiating high-grade gliomas from low-grade ones without concentration time curve (CTC).
  
  
  METHODS
  TSM-based rCBV (rCBV TSM ) and conventional rCBV (rCBV PWI ) maps were generated (n = 35). The differences in percentage and concordance correlation coefficient (CCC) of the rCBV TSM and rCBV PWI ratios were calculated. The Mann-Whitney test and the receiver operating characteristic (ROC) curve analysis were also performed to examine the relationships of rCBV ratios between high- and low-grade gliomas. The improvement factors of signal to noise ratio (SNR) of rCBV TSM maps were also calculated.
  
  
  RESULTS
  The mean difference in percentage between rCBV TSM and rCBV PWI ratios was 4.29 ± 2.62%. The CCC of rCBV TSM and rCBV PWI ratios was 0.9974, with 95% confidence interval of 0.9948, 0.9987, which implied a high agreement between them. The Mann-Whitney test suggested that the rCBV TSM and rCBV PWI ratios of high-grade gliomas were significantly different from those of low-grade gliomas (P < 0.001). The improvement factors of SNR of the rCBV TSM map were 1.31 ± 0.24 for glioma and 1.28 ± 0.24 for normal white matter.
  
  
  CONCLUSIONS
  It is feasible to use rCBV TSM in the evaluation of hemodynamic characteristics of gliomas and differentiation of high- and low-grade gliomas without CTC. Moreover, rCBV TSM maps possess a higher SNR, which allows potentially more accurate diagnosis compared with the conventional ones.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China.
authors.forename: Chun-Hong
authors.initials: CH
authors.lastname: Hu
authors.forename: Su
authors.initials: S
authors.lastname: Hu
authors.forename: Xi
authors.initials: X
authors.lastname: Gao
authors.forename: Chun-Ming
authors.initials: CM
authors.lastname: Sun
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Gan
authors.forename: Yun-Lian
authors.initials: YL
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Wen
authors.forename: Qi-Chun
authors.initials: QC
authors.lastname: Dai
authors.forename: Ping
authors.initials: P
authors.lastname: Li