Novel fast FFR derived from coronary CT angiography based on static first-pass algorithm: a comparison study.

BACKGROUND: Fractional flow reserve (FFR) is the invasive gold standard for evaluating coronary arterial stenosis. However, there have been a few non-invasive methods such as computational fluid dynamics FFR (CFD-FFR) with coronary CT angiography (CCTA) images that can perform FFR assessment. This study aims to develop a new method based on the principle of static first-pass of CT perfusion imaging technique (SF-FFR) and evaluate the efficacy in direct comparisons between CFD-FFR and the invasive FFR. METHODS: A total of 91 patients (105 coronary artery vessels) who were admitted from January 2015 to March 2019 were enrolled in this study, retrospectively. All patients underwent CCTA and invasive FFR. 64 patients (75 coronary artery vessels) were successfully analyzed. The correlation and diagnostic performance of SF-FFR method on per-vessel basis were analyzed, using invasive FFR as the gold standard. As a comparison, we also evaluated the correlation and diagnostic performance of CFD-FFR. RESULTS: The SF-FFR showed a good Pearson correlation (r = 0.70, P < 0.001) and intra-class correlation (r = 0.67, P < 0.001) with the gold standard. The Bland-Altman analysis showed that the average difference between the SF-FFR and invasive FFR was 0.03 (0.11-0.16); between CFD-FFR and invasive FFR was 0.04 (-0.10-0.19). Diagnostic accuracy and area under the ROC curve on a per-vessel level were 0.89, 0.94 for SF-FFR, and 0.87, 0.89 for CFD-FFR, respectively. The SF-FFR calculation time was about 2.5 s per case while CFD calculation was about 2 min on an Nvidia Tesla V100 graphic card. CONCLUSIONS: The SF-FFR method is feasible and shows high correlation compared to the gold standard. This method could simplify the calculation procedure and save time compared to the CFD method.

Study on the cephalopelvic relationship with cephalic presentation in nulliparous full-term Chinese pregnant women by MRI with three-dimensional reconstruction.

PURPOSE: To analyze the relationship between fetal head size and maternal pelvis size using magnetic resonance imaging (MRI) with a 3-D reconstruction technique. METHODS: A total of 301 nulliparous full-term Chinese pregnant women with cephalic presentation were enrolled and received MRI examinations before labor onset. Data were collected and imported into Mimics software to reconstruct the maternal pelvis and fetus. RESULTS: Of 301 pregnant women, 212 underwent vaginal delivery and 32 received cesarean section. The body mass index (BMI) was significantly different between the vaginal delivery group and the suspected cephalopelvic disproportion (CPD) group; the larger the BMI, the higher was the risk of CPD. The transverse diameter of the pelvic inlet and the posterior sagittal diameter of the midpelvis were significantly larger in the vaginal delivery group, compared with the suspected CPD group. Fetal weight > 3.5 kg could be used as a diagnostic indicator for CPD. CONCLUSIONS: BMI is a risk factor for CPD, and fetal weight < 3.5 kg is an important diagnostic indicator for natural delivery in Chinese pregnant women.

[Association of the CYP1B1 gene polymorphism with susceptibility to endometriosis].

OBJECTIVE: To study the association between gene polymorphisms of cytochrome P450 1B1 (CYP1B1) in exon 2 codon 119 (G-T) and exon 3 codon 432 (C-G) and the susceptibility to endometriosis. METHODS: Allele-specific polymerase chain reaction was used to analyze the gene polymorphisms in 55 cases of endometriosis and 45 cases of normal controls. RESULTS: The frequencies of alleles G and T in codon 119 G/T of CYP1B1 gene showed a significant difference between the endometriosis group and the control group (P<0.05), with an odds ratio of 2.061. There was a significant difference in the frequencies of genotypes G/G, G/T and T/T between the two groups (P<0.05). Compared with wild-type G/G, the susceptibility of endometriosis with genotypes T/T and G/T was 2.625 and 3.214 fold, respectively. In the population with combined genotypes of CYP1B1 codon 119 GT or GG-codon 432 CC, statistically significant difference was observed between cases and controls (GT+CC vs GG+CC, OR=2.976, P<0.05). CONCLUSION: The gene polymorphisms of CYP1B1 in exon 2 codon 119 may be a genetic risky factor for endometriosis. The combination of CYP1B1 -GT and CYP1B1 -CC may act as a risky factor in the development of endometriosis.