Fig. 3

Case 3: 13 year old boy presenting with steroidresponsible opsoclonus-myoclonus syndrome. No I-123 MIBG tracer uptake could be detected in scintigraphy after the administration of 108 mBq I-123-mIBG (a). WB-MRI revealed a paravertebral right-sided retroperitoneal mass (white arrow) at the level of T11 to L1 with hyperintensity in T2 weighted sequences (b, axial T2w and c, coronal) and contrast enhancement in the post-contrast T1 weighted sequence after intravenous injection of 7 ml gadolinium compound (d, native T1 weighted sequence and E, post-contrast T1 weighted sequence). L = liver, S = spleen