Medulloblastoma with extensive nodularity: single photon emission CT study with iodine-123 metaiodobenzylguanidine.

We present the case of an infant with medulloblastoma with extensive nodularity, which had been called cerebellar neuroblastoma. MR imaging clearly revealed a nodular enhancement, which appeared as a grape-like lesion. Single photon emission CT revealed markedly high iodine-123 metaiodobenzylguanidine uptake in the enhancing tumor. Iodine-123 metaiodobenzylguanidine single photon emission CT may be useful in the diagnosis of medulloblastoma with extensive nodularity, which has been considered to be a subgroup of medulloblastoma with extensive neuronal differentiation.