Objective To explore the significance and clinical value of 64-slice spiral CT angiography and postprocessing technology in the diagnosis of isolated superior mesenteric artery dissection(SIDSMA).Methods The clinical data,multi-slice spiral CT angiography,and image post-processing technology of 23 patients with SIDSMA in our hospital from 2021 to 2023 were analyzed retrospectively,and the CT manifestations of SIDSMA were discussed.Results There were obvious double-lumen changes in all 23 patients,20 cases showed intimal film and 20 cases showed intimal rupture.The interlayer range is 18~62 mm,with an average of(40±7)mm.The break is 21~30 mm from the beginning of superior mesenteric artery(SMA),with an average of(25±5)mm.Conclusion MSCT angiog-raphy and image post-processing technology can clearly and intuitively display the true and false cavities,intima films,the position of rupture and its relationship with surrounding tissues and structures of SIDSMA,and can also measure the data such as the range of interlayer and the distance from the rupture to the beginning of SMA,which is of great significance to the selection of clinical treatment methods.