Evaluating placental microstructure and microcirculation in predicting the progression of gestational hypertension to preeclampsia: a systematic comparison between virtual MR elastography, IVIM, ultrasound and lab indexes.

OBJECTIVE

We aimed to utilize functional magnetic resonance imaging (fMRI), including placental virtual magnetic resonance elastography (vMRE), intravoxel incoherent motion (IVIM) parameters, MRI morphological parameters, ultrasound and laboratory indexes to predict the progression of GH to PE and differentiate patients with GH and controls.

METHODS

Between January 2018 and March 2023, we retrospectively collected 382 pregnant women and ultimately included 68 subjects: 24 with PE, 14 with GH, and 30 healthy controls. The stiffness value (μdiff) from vMRE, true diffusion coefficient, pseudo-diffusion coefficient, perfusion fraction (f) from IVIM-based analysis, and apparent diffusion coefficient were calculated. MRI morphological parameters were evaluated using T2-weighted imaging. Doppler parameters of the umbilical artery (UA) and middle cerebral artery, cerebroplacental ratio (CPR), and laboratory tests were retrospectively collected. ANOVA analysis compared parameters across three groups. Predictive performance was evaluated using receiver operating characteristic curve analysis and area under the curve (AUC).

RESULTS

Doppler parameters (pulsatility index, resistance index, peak systolic velocity/end-diastolic velocity in UA, and CPR) and fMRI parameters (μdiff and f) effectively predicted PE in patients with GH. The fMRI combined model exhibited superior predictive efficacy compared to the Doppler model (AUC, 0.845 vs. 0.792). Their combined model further improved predictive efficacy (AUC, 0.920). The prothrombin time level, μdiff and f could identify patients with GH and controls, with no substantial differences in all Doppler parameters.

CONCLUSIONS

vMRE and IVIM parameters might be superior to ultrasound and laboratory indexs in predicting the progression of GH to PE and differentiating patients with GH and controls.