Edinburgh Imaging

MSc projects 1718 006

The role of MR perfusion in treatment-related changes in high-grade gliomas of the brain. Differentiation between pseudoprogression, ractionecrosis, & recurrence.

  • Background: The purpose of this meta-analyis is to assess the accuracy of MR perfusion in differentiating between tumor and treatment related changes in patients with high-grade gliomas. Our main purpose was to evaluate the (DSC) perfusion-weighted imaging parameters and especially Rcbv value.  
  • Methods: An extensive literature search was performed from 1997 until November 3d 2017 using the Ovid Gateway and selected Embase and Medline databases. Additionally, the search was performed by Google scholar and discovered library of the University of Edinburgh. The quality of eligible studies was assessed according to the Quality Assessment of Diagnostic Accuracy Studies-2 (QADAS-2). The assumption of the homogeneity of the actual magnitudes of the results was evaluated by a Cochrane Q test and the degree of inconsistency in the studies was calculated by the I inconsistency index. Spearman correlation coefficient between the logit of 1-specificity and the logit of sensitivity was calculated to test the threshold. Pooled analyses were performed using the software Rev Man 5.3. Sensitivity and specificity, positive and negative (LR+/ LR-) with a 95% confidence interval (CI) were re-calculated for each study from trne positives, false positives, false negatives, and trne negative negatives using the Review Manager 5.3  
  • Results: Of 648 abstracts screened, 17 articles were included. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio , diagnostic odds ratio were 0.852(95%CI 0.819-0.880), 0. 783(95%CI, 0.727-0.833), Positive likelihood ratio 3,367 (95% CJ 2,673-4,242), Negative likelihood ratio 0.212(95%CJ 0.162- 0.276) and diagnostic odds ratio 18.380(95%CI 12,130-27,849. The AUC under the SROC was 0.8451. The result indicates that the accuracy of the prediction of the Rcbv is good and moreover the average area under the ROC curve could be considered high. The funnel plot of the 20 studies were symmetrical.  
  • Conclusion: In conclusion rcbv has a good diagnostic accuracy and can improve the diagnosis of high grade glioma recurrence compared with conventional MRI techniques. Has moderately high degree of differentiating tumor recurrence from radiation necrosis and pseudoprogression. Also by combining MR perfusion with other modalities we can achieve increased sensitivity and specificity.
Project type:
  • Literture review
Imaging keywords:
Application / disease keywords:
  • Gliomas
  • Pseudoprogression
  • Radiation necrosis
  • 17-18