The ratio of superior mesenteric artery diameter to superior mesenteric vein diameter based on non-enhanced computed tomography in the early diagnosis of spontaneous isolated superior mesenteric artery dissection

Abstract

Background: Spontaneous isolated superior mesenteric artery (SMA) dissection (SISMAD) is a rare cause of abdominal pain. The aim of the study is to investigate the role of a new parameter, the ratio of the SMA diameter to the superior mesenteric vein (SMV) diameter (SMA/SMV) based on non-enhanced computed tomography (CT), in the early diagnosis of SISMAD.

Methods: In a registry study from December 2013 to June 2021, 97 abdominal pain SISMAD patients (SISMAD group) admitted to our hospital were enrolled. Meanwhile, the matched sex and age abdominal pain non-SISMAD patients at 1:2 were collected in reverse chronological order as the control group. Student's t-test, Wilcoxon rank-sum test, and Chi-square test were used to compare differences between the SISMAD and control groups. MedCalc was used to generate receiver operating characteristic (ROC) curve.

Results: A total of 291 abdominal pain patients, including 97 SISMAD patients and 194 non-SISMAD patients, were included in the current study. The maximum SMA diameter, perivascular exudation, and SMA/SMV based on non-enhanced CT were significant between the two groups (all P<0.05). ROC curves showed that for the maximum SMA diameter, the area under the curve (AUC), cut-off, sensitivity, and specificity were 0.926, 9.80, 93.8%, and 79.4%, respectively. For SMA/SMV, its AUC, cut-off, sensitivity, and specificity were 0.956, 0.83, 88.7%, and 92.3%, respectively. The diagnostic efficiency of SMA/SMV was better than that of the maximum SMA diameter (P<0.05). The combined parameters of SMA/SMV and maximum SMA diameter had the best diagnostic efficiency (AUC=0.970).

Conclusion: SMA/SMV may be a potential marker for SISMAD.

Keywords: Abdominal pain; Computed tomography; Receiver operating characteristic curve; Spontaneous isolated superior mesenteric artery dissection.

Figure 1

ROC curves. ROC curves showing the AUC, cut-off, sensitivity and specificity of the maximum SMA diameter (A), SMA/SMV (B), combined parameters of maximum SMA diameter and perivascular exudation (D), SMA/SMV and perivascular exudation (E), and SMA/SMV and maximum SMA diameter (G). In the diagnostic efficiency aspect, SMA/SMV was better than the maximum SMA diameter (P<0.001, C). The combined parameters of SMA/SMV and perivascular exudation were better than the maximum SMA diameter and perivascular exudation (P<0.05, F); the combined parameters of SMA/SMV and maximum SMA diameter were the best (P<0.05, H). If the value of the maximum SMA diameter was X (mm), SMA/SMV was Y, and perivascular exudation was Z (if have, Z=1; if not, Z=2), then the value of X+Z = –17.418+1.602*X+1.135*Z; the value of Y+Z = –16.718+19.016*Y+0.928*Z; and the value of X+Y = –23.742+1.012*X +15.624*Y. ROC: receiver operating characteristic; AUC: area under the curve; SMA: superior mesenteric artery; SMA/SMV: the ratio of the SMA diameter to the superior mesenteric vein diameter.