Aortic Major Diameters Comparison














The pictures above are measurements done by Stanford’s 3DQ Lab and are taken from one patient’s CT scans over a 3 year period.  It shows an aortic dissection that becomes aneurysmal. An aneurysm is defined as an abnormal bulge of a major blood vessel that transmits blood from your heart to other organs. An aortic dissection is a tear in the inner wall of the aorta. As the tear expands along the wall of the aorta, blood can flow in between the aortic layers and can cause the aorta to expand. Both aneurysms and dissections can be life threatening.

Stanford 3DQ Lab Technologists provide serial measurements of the aorta at predetermined locations along the length of the aorta for our cardiovascular surgeons. This enables them to track regions within the aorta that increase due to the presence of an aneurysm or aortic dissection. Figure 1a is a diagram of the aorta; the green arrow points to the location of the measurements shown in Figs. 2a-c.  Figure 2a shows an aortic dissection whose is within the normal range, and there is no aneurysm present. Figure 2b shows a measurement at the same location 2 years later, revealing a significant increase in the size of the aorta. If the diameter crosses a threshold, the surgeon may decide to take the patient to surgery. Figure 2c shows a measurement done 1 year later following the implantation of a stent-graft in the aorta. A stent-graft is metal web covered with material that is delivered to the diseased aorta through a catheter to create a new inner wall without having to perform major abdominal surgery.

Once the 3DQ Lab technologists complete all of the measurements, the diameters obtained are entered into a database and delivered to the cardiovascular surgeons in a  report. Figure 3a is an example of such showing the growth of the aorta over time for this patient. The measurements that the 3DQ Lab technologists provide are critical to the surgical decision-making.