Fig. 6

Two different patients with filler injections performed under unclear circumstances (patient 1, 53-year-old woman, a-c; patient 2, 46-year-old woman, d-f) developed diffuse swelling and induration of the lips and cheeks 1 year after the respective procedures. The injected filler was a mixture of CHA and collagen in patient 1, and it was not known in patient 2. In both patients, the filler and the resulting soft tissue changes show intermediate-to-low signal intensity on T2 W images (arrows in a, d), and nodular and strong enhancement on postgadolinium T1 W images (arrows in b, e) suggesting an inflammatory reaction. However, in patient 1, the injected areas appear hypointense on the silicone only sequence (arrows in c), whereas in patient 2 the injected areas appear strongly hyperintense. Based on these images, the diagnosis of granuloma formation due to CHA and collagen in patient 1 and due to silicone oil in patient 2 was made. Biopsy obtained in both patients confirmed the radiologic diagnosis, in particular biopsy also confirmed the presence of silicone with a characteristic Swiss cheese pattern at histology