CT diagnosis of nutcracker syndrome / 实用放射学杂志

ABSTRACT

Objective To investigate the diagnostic value of some measured values of CT for nutcracker syndrome(NCS).Methods 28 patients with NCS confirmed by clinical diagnosis and other 81 normal controls were enrolled in the study.The angle between the superior mesenteric artery and the abdominal aorta,and the diameter and the area of left renal vein before/within this angle were measured on enhanced CT and MPR reconstruction images.The ratios of the diameter and the area before the angle to those within the angle were calculated.ROC curve was established to calculate the cut-off value and to evaluate the sensitivity,specificity,positive predictive value and negative predictive value of these parameters.Results In patient group,the mean aortomesenteric angle was 22.4°± 7.16°,mean diameter ratio was 5.10 ± 1.76 and the mean area ratio was 4.07 ± 2.10.In control group,the mean aortomesenteric angle was 61.32°± 22.82°,mean diameter ratio was 1.38 ± 0.40 and mean area ratio was 1.29 ± 0.49.The area under the ROC of the aortomesenteric angle,and the diameter ratio and area ratio were 0.979,1.000 and 0.989 respectively with corresponding cut-off values of 32.5°,2.63 and 2.06,sensitivity of 92.8%,100% and 96.4%,specificity of 95.1%,100% and 92.6%,positive predictive value of 86.7%, 100% and 81.8%,and negative predictive value of 97.5%,100% and 98.7%,respectively.Conclusion The aortomesenteric angle, the diameter and area ratios of left renal vein before/within the aortomesenteric angle have significant diagnostic value in the patients with NCS,and the value of diameter ratio is the highest.