Preliminary clinical application of total free-breathing cardiac MR examination

Objective To observe the clinical application value of total free-breathing cardiac MR(CMR)examination preliminarily.Methods Two patients who underwent CMR scanning under free-breathing state,including cine,motion correction T1 and T2 mapping,blood flow imaging,and late gadolinium enhancement scanning were retrospectively enrolled,and the qualities of the above images were evaluated and compared with that of conventional CMR images under breath-holding state.Results No significant difference of imaging quality was found between total free-breathing and conventional breath-holding CMR.The differences of left ventricular ejection fraction,cardiac output,left ventricular end-diastolic volume index and left ventricular mass measured based on CMR images under different breath conditions were limited.Conclusion Total free-breathing CMR was feasible in clinical practice,which could provide"one-stop"evaluation of cardiac structure,function and myocardial histological characteristics,hence having promising clinical prospects.

Diagnostic value of whole-body MRI with diffusion-weighted sequence for detection of peritoneal metastases in colorectal malignancy

Objective:To assess the diagnostic accuracy of whole-body MRI using diffusion-weighted sequence(WB-DWI)to determine the peritoneal cancer index(PCI)in correlation with surgical and histopathological findings.Methods:Twenty-seven patients underwent preoperative WB-MRI,followed by cytoreductive surgery for primary tumors of the appendix(n=15),colorectum(n=12),and associated peritoneal disease.A total of 351 regions were retrospectively reviewed.The sensitivity,specificity,and accuracy were calculated at 13 anatomical sites.The WB-DWI PCI and PCI type were compared with surgical and histopathological findings.Results:No statistical difference was found between the WB-DWI PCI and surgical PCI(P=0.574).WB-DWI correctly predicted the PCI type in 24 of 27 patients with high accuracy(88.9%),including 10 of 10 patients with small-volume tumor,12 of 14 with moderate-volume tumor,and 2 of 3 with large-volume tumor.WB-DWI correctly depicted tumors in 163 of 203 regions,with 40false-negative and 23 false-positive regions.The overall sensitivity,specificity,and accuracy of WB-DWI for the detection of peritoneal tumors were 80.3%,84.5%,and 82.1%,respectively.For lesions<0.5 cm in diameter,WB-DWI demonstrated good sensitivity(69.4%).Conclusions:WB-DWI accurately predicted PCI before surgery in patients undergoing evaluation for cytoreductive surgery.