Functional diagnosis of placenta accreta by intravoxel incoherent motion model diffusion-weighted imaging

Objectives To investigate the diagnostic value of intravoxel incoherent motion (IVIM) DWI for placenta accreta by comparing diffusion and perfusion characteristics of placentas with accreta lesions (APs) with those of normal placentas (NPs). Methods Twenty-five pregnant women with AP and 24 with NP underwent 3-T magnetic resonance examinations with IVIM-DWI. The perfusion percentage (f), pseudo-diffusion coefficient (D*), and diffusion coefficient (D) values were calculated from different ROIs: the entire-plane of the AP (AP-ROI) and NP (NP-ROI) and the implanted (IR-ROI) and non-implanted region (NIR-ROI) of the AP. The AP-ROIs and NP-ROIs were compared using covariance analysis; the IR-ROIs and NIR-ROIs were compared using the Wilcoxon signed-rank test. ROC curves were produced to evaluate the parameters for predicting placenta accreta. Results ThefandD* values for the AP-ROIs ([45.0 +/- 7.63]%, [11.64 +/- 2.15]mm(2)/s) were significantly higher than those for the NP-ROIs ([31.85 +/- 5.96]%, [9.04 +/- 3.13]mm(2)/s) (bothp< 0.05); the IR-ROIs (54.8%, 14.03 mm(2)/s) were also significantly higher than the NIR-ROIs (37.4%, 11.4 mm(2)/s) (bothp< 0.05). No significant differences were found between theDvalues of the AP-ROIs and NP-ROIs (p> 0.05) or of the IR-ROIs and NIR-ROIs (p> 0.05). The areas under the curve forfandD* of the ROC curves were 0.93 and 0.79, respectively. Conclusions These results suggest that the IVIM parametersfandD* can be used to quantitatively evaluate the higher perfusion of AP when compared with NP. Furthermore, IVIM may be a useful functional diagnostic technique to predict placenta accreta.

Automated summary

The study found that IVIM parameters f and D* can quantitatively evaluate the higher perfusion in AP compared to NP. Additionally, IVIM may be a useful functional diagnostic technique for predicting placenta accreta.