The Value Of Susceptibility Weighted Imaging In Fetal Spinal Imaging

Purpose:To evaluate the image quality of conventional MRI sequence and susceptibility weighted imaging(SWI),and to assess the learning competence of junior physicians to locate the designated vertebral body of the fetus in conventional MRI sequences and SWI images.Methods:22 pregnant women over 22 weeks of gestation were included in this study.Conventional MRI sequences and SWI sequences were scanned under 1.5T MRI.The image quality of two sequences were recorded and compared,including qualitative analysis and quantitative analysis.Qualitative analysis of the image was graded by two doctors using the five-point confidence scale,and the visibility of vertebral bodies and appendages was subjectively graded by the five-point confidence scale.Quantitative analysis includes the contrast noise ratio(CNR)of the image and the number of vertebrae and ribs clearly displayed in routine MRI sequence and SWI.The time required to locate the 12 thoracic vertebrae in routine MRI sequence and SWI was recorded by two junior physicians,respectively.The vertebral body was labeled.The time required for two junior physicians to locate the vertebrae is compared.The results of markingvertebral bodies of two junior doctors were compared with senior doctors,and the cumulative sum(CUSUM)analysis was used to evaluate the performance of the two junior doctors.Results:In terms of conventional MRI sequence and SWI sequence image quality scores,both qualitative analysis and quantitative analysis showed statistical differences(p < 0.05).The time required for the localization of the 12 thoracic vertebrae in the SWI image was significantly less than that in the conventional T2 WI image.According to CUSUM results of two junior physicians,compared with conventional T2 WI images,fewer images were read in SWI images,while CUSUM curve showed an upward trend and the positioning accuracy of the vertebral body became stable.Conclusion:Sensitivity weighted imaging(SWI)can better display the anatomical structure of the fetal spine than conventional MRI sequences.Comparing the learning curve of locating the designated vertebral body of the fetus in the conventional MRI sequences and the SWI images,junior physicians can achieve accurate positioning of the vertebral body in less time and read fewer images in the SWI images.