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The following is a summary of “Neuroimaging changes in the pregeniculate visual pathway and chiasmal enlargement in Leber hereditary optic neuropathy,” published in the January 2024 issue of Ophthalmology by Xu et al.

Researchers conducted a retrospective study to characterize the MRI alterations in the pregeniculate visual pathway in Leber hereditary optic neuropathy (LHON).

They enrolled 60 LHON patients (January 2015 and December 2021) in a retrospective observational study. The study investigated abnormal MRI features within the pregeniculate visual pathway and examined their correlation with the causative mitochondrial DNA (mtDNA) mutation, MRI lesion distribution, and duration of vision loss.

The result showed that the cohort comprised 48 (80%) males, with 53 (88%) experiencing bilateral vision loss. The median age of onset was 17.0 years (range 4.0–58.0). 28 (47%) patients harbored the m.11778G>A mutation. T2 hyperintensity (HS) in the pregeniculate visual pathway was observed in 34 (57%) patients, while 13 (22%) exhibited chiasmal enlargement. Notably, 20 patients (71%) with the m.11778G>A mutation manifested T2 HS, significantly more than the 14 patients (44%) in other LHON mutation groups (P=0.039). A higher proportion of patients in the m.11778G>A group (16 patients (57%)) displayed T2 HS in the optic chiasm (OCh)/optic tract (OTr) compared to other LHON mutation groups (7 patients (22%), P=0.005). Optic chiasmal enlargement was more prevalent in patients with vision loss duration <3 months than those ≥3 months (P=0.028).

Investigators concluded that LHON patients with m.11778G>A mutation exhibit heightened early T2 HS and chiasmal enlargement, suggesting potential diagnostic utility.

Source: bjo.bmj.com/content/early/2024/01/17/bjo-2023-324628