Objective: To prove that CTA can be used as the modality of choice for final diagnosis of and management decision of aortic dissection, and also to analyze CTA appearances of the aortic dissection. Methods: Aortic CTA images of 145 patients between Sept 1, 2003-Aug 31, 2005 at King Chulalongkorn Memorial Hospital (KCMH) were reviewed by two consensus radiologists. These patients’ history of management decisions and results of treatment were also reviewed. The incidence of aortic dissection and the image appearances were also analyzed. Results: The incidence of aortic dissection at KCMH was 31 cases in two years of wich 11 cases were classified as type A (35 %), while 20 cases into type B (65 %). No patient required another investigative modality after CTA diagnosis of aortic dissection. True/false lumens, intimal tear, peri-aortic fluid, pleural effusion, pericardial effusion, intramural hematoma and contrast leakage were imaging findings obtained in that order. Conclusion: CTA can replace theconventional invasive aortography and can be used as the modality of choice for management decision of aortic dissection.