TEE image of the proximal ascending aorta (approximately at level of sinotubular junction) in mid-esophageal short axis view. The true lumen (TL) can be seen with the right, left, and noncoronary cusps. The false lumen (FL) is clearly obvious and occupies approximately forty percent of the aortic luminal area. This pathology caused severe aortic insufficiency which was demonstrable with color flow doppler (not shown).