Aortic dissection - Stanford A /DeBakey I

• Aneurysmalaneurysmal dilatation of the ascending aorta, aortic arch and descending aorta with a aspiralspiral intimal flap is seen denoting aortic dissection.
• Mildmild dilatation of the left atrium with concentric hypertrophy of the left ventricle, no gross cardiomegaly. No pericardial effusion.
• Thethe left thyroid lobe is seen enlarged with a small retrosternal extension, it shows heterogeneously isointense T1 and hyperintense T2 signal intensity. The lesion is seen displacing the trachea to the right side.
• Nono other mediastinal or hilar masses or lymph nodal enlargement.
• Smallsmall bilateral basal atelectatic bands.
• Mildmild para-cardiac bat-wing alveolar haze suggestive of mild bilateral pulmonary edema with probably pulmonary venous hypertension.
• Thickenedthickened left apical pleural cap.
• Minimalminimal right pleural effusion.

• Anan aortic dissecting intimal flap seen spiraling along the whole aorta extending from its root down to its bifurcation and through into the left common iliac artery (CIA).
• Thethe dissected intimal flap is seen dividing the aortic lumen into false and true lumina, with the false lumen is much larger than, and compromising, the true lumen in the distal aortic arch and the whole descending aorta, while the true lumen is larger in the ascending aorta and almost equal to the false lumen in the proximal arch. The false lumen is not thrombosed. The dissection flap shows two fenestrations at the ascending aorta and another two at the mid arch.
• Consequentconsequent dilatation of the ascending aorta (5 cm in diameter) and the descending thoracic aorta (5.7 X 4.9 cm) is noted.
• Thethe narrowest true lumen is seen at D11 level measuring 21.4 X 9.3 mm.
• Almostalmost all the main branches of the different segments of the aorta arise from the true lumen, except the left CIA which is seen involved by the false lumen with no appreciable dilatation.
• Nono evidence of aortic wall rupture or extra-aortic contrast leak.

• Evidenceevidence of bilateral pulmonary edema with para-cardiac batwing alveolar haze as well as interstitial edema with indistinct vessels and thickened interlobular septa. This is most probably due to pulmonary venous hypertension.  

Aortic dissection with intimal flap involving the whole aorta (Stanford type A, DeBakey type I) down to the left CIA with the other aortic branches arising from the true lumen, non-thrombosed false lumen and no extra-aortic leak.

(The case is courtesy of Dr. Ahmad Yousry, MD and Dr. Mohammed A. ElBeialy, MD, FRCR)