Figure 5a. Severe aortic valve stenosis in an 80-year-old patient. Degree of calcification of the tricuspid aortic valve was graded as moderate (grade 3, multiple larger spots of calcification) on both (a) nonenhanced and (b) contrast-enhanced multi-detector row CT images. Image quality was rated as poor (grade 2, poor visibility of the anatomic details of the aortic valve) on a and as good (grade 3, good visibility of the anatomic details of the aortic valve) on b. Note aortic valve calcification (large arrows), aortic valve leaflets (small arrows), free edges of the aortic valve leaflets (black arrowheads on b), and aortic valve annulus (white arrowheads on b).