J Korean Radiol Soc.
1994 Dec;31(6):1033-1038.
The Role of CT and MR in Diagnosis of Aortic Dissection
Abstract
- PURPOSE
The purpose of this study was to determine the role of CT and MR imagings in the diagnosis
aortic dissection and differentiation between the true and false lumen.
MATERIALS AND METHODS
We retrospectively studied forty patients with aortic dissection(AD) diagnosed
imagings or surgery. Of the forty patients, 19 were examined with only CT, 14 with CT and MR, and 7 with MI~:
Our points of view were(1) the classification of AD according to configuration of intimal flap by cross-sectional
imaging, (2) differentiation between the true and false lumens, (3) the course of the false lumen, and (4)!
detectability of the origin of major branch vessels of the abdominal aorta.
RESULTS
The classification by corss-sectional imaging were crescentic(65%), circumferential(15%), flat(12%),
and irregular(8%) type, in which false negative diagnosis was made in 1 case of crescentic and circumferential
type, respectively. In 2 case of flat type and 1 case of irregular type, the differentiation between the true and
false lumen was impossible with CT. The course of the false lumen in descending thoracic aorta revealed
countrclock wise rotation(66%), clockwise rotation(5%) or fixed(29%) apperance. MR imaging was superior to
CT in the detection of the origin of major branch vessels of the abdominal aorta. The determination of the origin
of major branches of abdominal aorta arising from the true and false lumen were impossible in 2 cases in
which only CT was done.
CONCLUSION
Diagnosis of crescentic and circumferential types of AD with narrow and thrombosed false
lumen was problematic in both CT and MR with no difference of diagnostic accuracy between the two modalities.
The differentiation between the true and false lumen was difficult in flat and irregular types with only CT.
Therefore, when surgical treatment is considered as in type B aortic dissection, MR imaging is recommended in
order to determine the origin of major branch vessels.