OPA1 and optic nerve disorder: The current literature reports 8 patients carrying LHON mtDNA mutations and 2 patients harboring OPA1 mutations who developed optic neuropathy during the use of EMB (Dotti et al., 1998; De Marinis, 2001; Hwang et al., 2003; Chowdhury et al., 2006; Ikeda et al., 2006; Guillet et al., 2010; Pradhan et al., 2010; Seo et al., 2010).