Suspected invasive placenta: evaluation with magnetic resonance imaging.

PURPOSE: To determine the utility of magnetic resonance imaging (MRI) in diagnosing invasive placenta (IP). MATERIALS AND METHODS: MRI findings in 32 women with suspected IP were evaluated independently by four readers. Interobserver agreement was calculated with kappa (κ) statistics. Associations between MRI findings and IP were assessed by univariate and multivariate analyses. Sensitivity, specificity and accuracy of MRI for the diagnosis of IP were estimated. RESULTS: Sixteen women (16/32; 50%) had confirmed IP. Interobserver correlation for the diagnosis of IP was fair (κ = 0.40). Univariate analysis revealed that thinning or focal defect of the uteroplacental interface (P < 0.0001) was the most discriminating MRI variable in the differentiation between normal and IP. Overall sensitivity and specificity of MRI for the diagnosis of IP were 84% [95% CI: 75-94%] and 80% [95% CI: 66-93%], respectively. Thinning or focal defect of the uteroplacental interface was the most accurate finding (88%) in the diagnosis of IP. Multivariate analysis revealed that thinning or focal defect of the uteroplacental interface was the single independent predictor of IP (P = 0.0006; OR = 64.99). CONCLUSION: MR imaging has 84% sensitivity [95% CI: 75-94%] and 80% specificity [95% CI: 66-93%] for the diagnosis of IP. Thinning or focal defect of the uteroplacental interface is the most discriminating independent MR variable in differentiating between normal placenta and IP. KEY POINTS: MR imaging has acceptable degrees of accuracy to diagnose invasive placenta. Focal uteroplacental interface defect is the best finding to diagnose invasive placenta. Focal uteroplacental interface defect is the single independent predictor of invasive placenta.

Innovative DIEP flap perfusion evaluation tool: Qualitative and quantitative analysis of indocyanine green-based fluorescence angiography with the SPY-Q proprietary software.

BACKGROUND: Perfusion-related complications remain the most common concern in DIEP flap breast reconstruction. Indocyanine green-based fluorescence angiography can be used for the real-time intra operative assessment of flap perfusion. The SPY Elite system is the most widely used device in this setting. The main objective was to describe the use of SPY-Q proprietary software to perform qualitative and quantitative analysis of flap perfusion. METHODS: This retrospective cohort study was performed at the Curie Institute between 2013 and 2017. We included patients undergoing unilateral DIEP flap breast reconstruction for whom indocyanine green-based angiography videos were of sufficient quality for analysis. Videos were recorded with the SPY Elite System and analyzed with SPY-Q proprietary software. RESULTS: We included 40 patients. We used real-time dynamic color analysis to describe three different patterns of flap perfusion. SPY-Q proprietary software provides quantitative flap perfusion parameters. Our quantitative analysis confirmed that zone I is the best perfused part of the flap and zone IV the less perfused one. There was no significant association between flap perfusion pattern and perforator anatomy, patients' clinical characteristics or postoperative outcomes. After exploratory univariate analysis, quantitative perfusion parameters were significantly impaired in young patients with diabetes mellitus or under hormone therapy by tamoxifen. CONCLUSIONS: We here describe a new approach to assess DIEP flap perfusion using the SPY Elite System proprietary software. It provides interesting qualitative and quantitative analysis that can be used in further studies to precisely assess DIEP flap perfusion.

T2-weighted MR imaging of the liver: qualitative and quantitative comparison of SPACE MR imaging with turbo spin-echo MR imaging.

OBJECTIVE: To qualitatively and quantitatively compare T2-weighted MR imaging of the liver using volumetric spin-echo with sampling perfection with application-optimized contrast using different flip angle evolutions (SPACE) with conventional turbo spin-echo (TSE) sequence for fat-suppressed T2-weighted MR imaging of the liver. MATERIALS AND METHODS: Thirty-three patients with suspected focal liver lesions had SPACE MR imaging and conventional fat-suppressed TSE MR imaging. Images were analyzed quantitatively by measuring the lesion-to-liver contrast-to-noise ratio (CNR), and the signal-to-noise ratio (SNR) of main focal hepatic lesions, hepatic and splenic parenchyma and qualitatively by evaluating the presence of vascular, respiratory motion and cardiac artifacts. Wilcoxon signed rank test was used to search for differences between the two sequences. RESULTS: SPACE MR imaging showed significantly greater CNR for focal liver lesions (median=22.82) than TSE MR imaging (median=14.15) (P<.001). No differences were found for SNR of hepatic parenchyma (P=.097), main focal hepatic lesions (P=.35), and splenic parenchyma (P=.25). SPACE sequence showed less artifacts than TSE sequence (vascular, P<.001; respiratory motion, P<.001; cardiac, P<.001) but needed a longer acquisition time (228.4 vs. 162.1s; P<.001). CONCLUSION: SPACE MR imaging provides a significantly increased CNR for focal liver lesions and less artifacts by comparison with the conventional TSE sequence. These results should stimulate further clinical studies with a surgical standard of reference to compare the two techniques in terms of sensitivity for malignant lesions.