Wang D, Liu HL, Du YY, et al. - Researchers conducted this retrospective cross-sectional study to identify the peripapillary retinal nerve fibre layer (pRNFL) thickness changes in patients with Leber’s hereditary optic neuropathy (LHON) having m.11778G>A (MT-ND4) mutation. They involved 221 eyes from patients with LHON (n = 145) classified into seven groups according to disease duration and 52 eyes from healthy controls (n = 26). All individuals had pRNFL examinations. pRNFL thickness of the superior, nasal and inferior, and temporal quadrants, and the 360° average have been measured. The temporal pRNFL thickness decreased significantly within 3 months of onset, while the remaining quadrants and average pRNFL thickness increased initially. In LHON, the papillomacular bundle was first and preferentially affected. pRNFL thickness initially increased and then decreased, which leads to the retinal ganglion cell swelling and apoptosis. pRNFL thinning occurred first in the temporal quadrant, followed by the inferior and superior quadrants, and eventually, the nasal quadrant. In some quadrants, pRNFL continued to thin slowly even after 60 months.