MDCT evaluation of intimal defects in intramural hematoma of the aorta: initial findings and follow-up.

The purpose of this study is to assess the incidence and type of intimal defects in acute stage of the intramural hematoma (IMH) of the aorta using multi-detector CT (MDCT), and to see whether there was any difference in disease progression according to the presence and types of intimal defects. A retrospective analysis of 37 patients with following inclusion criteria was performed: (1) DeBakey type III IMH, (2) CT scans using 16-/64-channels MDCT within 24 h from symptom onset, and (3) no previous history of acute aortic syndrome. IMH patients were classified into 3 groups according to the initial MDCT findings: Group I included those patients without any intimal defects, Group II included those patients with ulcer-like projections, and Group III included those patients with atherosclerotic plaque ulcers. Thirty-four patients who underwent follow-up CT scans were assessed for changes in intimal defect size and hematoma thickness. For the initial CT studies, Group I included 6 patients, Group II included 7 patients, and Group III included 24 patients, In Group I, all patients showed regression of IMH without development of de novo intimal defects. However, in Groups II and III, intimal defect size was increased in 5 (83.3%) and 16 (72.7%) patients (P = 0.595), respectively. IMHs were complicated in 0 (0.0%), 1 (16.7%), and 4 (11.8%) patients in Groups I, II, and III, respectively (P = 0.587). Intimal defects are very common findings in the acute stage of IMH, and most of are associated with atherosclerotic plaque. Intimal defects have a tendency to increase in size in patients with ulcer-like projections or atherosclerotic plaque ulcers. However, IMHs improved with medical treatment, as shown by the decrease in hematoma thickness in all groups following treatment.