Perfusion fraction of diffusion‐weighted MRI for predicting the presence of blood supply in ovarian masses

Abstract

Purpose: To evaluate whether perfusion fraction (PF) calculated with diffusion-weighted magnetic resonance imaging (MRI) predicts the presence of blood supply in ovarian masses. Materials and Methods:PFs of 92 ovarian lesions in 53 patients administered gadolinium were retrospectively calculated with diffusion-weighted images at b-values of 0, 500, and 1000 sec/mm 2 . PFs were compared between ovarian lesions, except for fat, with (n ¼ 21) or without contrast enhancement (n ¼ 57), using Student's t-test and receiver operating characteristics (ROC) curve analysis. Lesion enhancement rates of contrast-enhanced images at 30 and 180 seconds after gadolinium injection (ER 30sec and ER 180sec ) and PFs were compared using Pearson's correlation coefficient.Results: PFs of the lesions with contrast enhancement were significantly higher than those without contrast enhancement (0.22 6 0.09 and 0.02 6 0.08, respectively, P < 0.0001). The ROC curve identified the best cutoff point for PF at 0.135 (95.2% sensitivity and 94.7% specificity) as a predictor of the contrast enhancement effect. The area under the ROC curve was 0.984. PF correlated moderately with ER 30sec (0.62, y ¼ 0.13x þ 0.04, P < 0.0001) and ER 180sec (0.74, y ¼ 0.13x þ 0.03, P < 0.0001).Conclusion: PF calculated with diffusion-weighted images can potentially predict blood supply in ovarian masses.

Comparison between types I and II epithelial ovarian cancer using histogram analysis of monoexponential, biexponential, and stretched‐exponential diffusion models

“…In the IVIM model, D* and f are linked to perfusion, and the perfusion level may indirectly reflect the degree of tissue vascularity without the use of contrast agents . Thus, the difference of f values between type I and type II cancers we found may have implications for the use of vascular targeted therapy .…”

Characterization of malignancy of adnexal lesions using ADC entropy: Comparison with mean ADC and qualitative DWI assessment

“…Further prospective studies would be helpful to validate our preliminary observations regarding a potential role of ADC entropy in assisting adnexal lesion characterization. In addition, we note that recent studies have shown potential of other functional techniques such as DWI with biexponential fitting (18), MR spectroscopy (19), and quantitative dynamic contrast‐enhanced MRI (20) in adnexal lesion characterization; these techniques may also be worthwhile to pursue given the limited utility of mean ADC that was observed in this study.…”

Intravoxel incoherent motion (IVIM) imaging at different magnetic field strengths: What is feasible?

“…(4) was chosen to be monoexponential since this approach has been extensively used in previous IVIM analyses [1][2][3][4][5][6][7][8][9][10][11][12]. However, experiments indicating that the signal attenuation arising from blood may indeed be biexponential have been presented [21][22][23], but these studies are few and performed exclusively on rat brain.…”

“…Only a few publications exist, where the IVIM technique has been explored for retrieval of the perfusion fraction in the brain [1][2][3]. However, the IVIM concept has been more frequently applied to organs with a larger blood volume, such as the liver, pancreas, kidney, heart, placenta and ovarian masses, in both humans and animals [4][5][6][7][8][9][10][11][12]. During the last decades, MRI hardware has developed considerably, showing an increase in main magnetic field strength and improved coil design (e.g., number of receiver coils).…”