POLG and Leber hereditary optic neuropathy: The prevalence of neuroradiological abnormalities was 9.8% and the five patients were characterized by different clinical phenotypes and mutations (MIDD, LS, ANS, LHON and LBSL were associated with m.3243A > G, m.13513G > A, POLG, m.11778G > A and DARS2 mutations, respectively; Table 2).