Eighteen patients (14 men, 4 women), ages 24 to 77 years, with a common celiacomesenteric trunk (CMT) were treated between 1965 and 2004 at the University of Michigan. Four patients had CMT aneurysmal or occlusive disease that led to operative treatment. Pertinent arteriographic findings in these 4 patients included a CMT aneurysm (n = 2), an occluded proximal CMT (n = 1), and a type III aortic dissection that was compressing the CMT (n = 1). Therapy in these 4 patients included placement of a polytetrafluoroethylene bypass graft from the supraceliac aorta to the CMT (n = 2) or a Dacron bypass graft from a thoracoabdominal bypass to the CMT (n = 1), and endovascular fenestration of the septum between the true and false lumens of an aortic dissection at the level of the CMT (n = 1).