Axial imaging of a patella slice with clinical gradient echo (A), GE with fat saturation (B), PD FSE (C), PD FSE with FS (D), T1 FSE (E), T1 FSE with FS (F), conventional UTE with a TE of 8 μs (G) and 6.6 ms (H), subtraction of the second echo from the first echo (I), fat saturated UTE with a TE of 8 μs (J) and 6.6 ms (K) with the corresponding later echo subtraction (L), and DIR UTE (M). Clinical GE or SE sequences show no signal from deep radial and calcified cartilage, which appears bright with UTE sequences but there is limited contrast between the deep layers of cartilage and superficial layers of cartilage as well as with bone marrow fat. The DIR UTE image shows the deep radial and calcified cartilage with high contrast (pink arrows) with good suppression of the signal from the superficial layers of cartilage and fat. There is some residual signal from the superficial layers of cartilage due to variation in its T1 (imperfect nulling).