<p><b>A</b>: Example of a large AML at the central part of the right kidney in a 33 year-old female TSC patient. <b>A1</b>: At baseline a heterogeneous AML with a mixed-signal on the T2 fat saturated MR sequence (solid arrows) could be visualized. Slow flowing blood in a small vessel (dotted arrows) appears hyperintense on the fat saturated sequence. The unaffected “healthy” kidney tissue is also visualized with a hyperintense signal (*). <b>A2</b>: 2.5 months following the initiation of the mTOR inhibitor therapy a reduction in the overall signal of the AML on the T2 fat saturated sequence can be visualized. The vessel, which was visible at baseline (A1: dotted line) cannot be delineated anymore. Additionally, a reduction of size of the AML can be visualized. This case represents a good example of how difficult it can be to clearly quantify a size reduction in a heterogenous AML following the initiation of mTOR therapy. <b>B</b>: Example of a AML at the caudal part of the right kidney in a 45 year-old male TSC patient. <b>B1</b>: At baseline a heterogeneous relatively bright angiomyolipoma could be visualized on the T2 fat saturated sequence (arrows). The unaffected “healthy” kidney tissue is visualized with a homogenous hyperintense signal on the T2 fat saturated sequence (*). <b>B2</b>: 3 to 6 months following the initiation of the mTOR inhibitor therapy, a clear reduction in the signal on the T2 fat saturated sequence as well as in the size of the angiomyolipoma is visualized. The signal of the healthy kidney tissue does not change following the initiation of the therapy (*). MRI: Magnetic Resonance Imaging. Fatsat: Fat saturated. Scale bar: 1.5 cm.</p
