Objective: The purpose of this study was to define the optimal Doppler criteria for the diagnosis of inferior mesenteric artery (IMA) stenosis in patients with suspected chronic mesenteric ischemia (CMI).
Methods: A retrospective review of 205 dedicated color and pulsed Doppler sonographic studies of mesenteric arteries was performed in 205 patients. All studies were performed in patients with suspected CMI. Correlative angiography was available in 50 patients.
Results: The IMA was visualized in 176 of 205 Doppler sonographic examinations (86%) and in 92% of the correlative studies. The visualization rate for the detection of a patent IMA by Doppler sonography in this series was 90%. The ranges of the peak systolic velocity (PSV), end-diastolic velocity (EDV), and mesenteric-aortic velocity ratio (MAR) in the nonstenotic IMA were 70 to 200 cm/s, 0 to 33 cm/s, and 0.7 to 3.7, respectively. The ranges of the PSV, EDV, and MAR in IMA stenosis were 200 to 485 cm/s, 0 to 177 cm/s, and 0.69 to 8.1. The threshold values for severe IMA stenosis by logistic regression analysis (n = 42) were as follows: PSV, greater than 200 cm/s; EDV, greater than 25 cm/s; and MAR, greater than 2.5, with sensitivities of 90%, 40%, and 80%; specificities of 97%, 91%, and 88%; positive predictive values (PPVs) of 90%, 57%, and 67%; negative predictive values (NPVs) of 97%, 83%, and 93%; and accuracy of 95%, 79%, and 86%, respectively.
Conclusions: We found that a PSV of greater than 200 cm/s was the best criterion for the diagnosis of IMA stenosis. The sensitivity, specificity, PPV, NPV, and accuracy for the PSV were 90%, 97%, 90%, 97%, and 95%, respectively.