Abstract
Purpose:
To report typical and atypical serial findings in three members of a LHON pedigree with an mt3460 mutation
Methods:
Three siblings born of a mother with acute onset LHON at age 20, an mt3460 genotype and 20/1000 VA were examined and followed over a 5 year period. The 300-year pedigree was noted for a history of profound vision loss, surprisingly preferential to females. The youngest sibling studied was a 7 year-old male with an initial best-corrected visual acuity (BCVA) of 20/20 OD and 20/25 OS. The second sibling studied was a 14 year-old female with BCVA 20/20 OD/OS. The third sibling was a 16 year-old male with BCVA 20/20 OD/OS. In addition to visual acuity, testing included fundus examination with fundus photography, OCT of the retinal nerve fiber layer (RNFL) and ganglion cell analysis (GCA).
Results:
The 7 year-old male had an atypical finding of pale discs OU. RNFL Analysis (Zeiss Cirrus) revealed RNFL loss superiorly, temporally, and inferiorly in both eyes. GCA revealed a profound loss of ganglion cells in the macula. Examination of the 14 year-old female revealed a hyperemic disc with peripapillary telangiectatic microangiopathy. The RNFL was thickened nasally in both eyes. GCA was statistically normal. Examination of the 16 year-old brother revealed mild peripapillary telangiectatic microangiopathy in both eyes. The right eye’s RNFL was normal but superior temporal thinning was seen in the left eye. Diffuse GCA thinning was seen in both eyes with denser loss inferiorly OD and temporally OS. Examination at 5 year follow-up revealed no change in any of the above findings in any of the two siblings with peripapillary telangiectatic microangiopathy. However, in the youngest sibling with pale discs, there was a one line reduction in visual acuity in both eyes but no additional changes in the examination findings.
Conclusions:
The rare presentation of early onset progressive LHON has only been reported in mt17778 pedigrees. This pedigree, with a mutation in the mt3460 locus, presents with characteristic findings of both typical LHON and rare atypical early-onset progressive LHON. Fundus photography, GCA, and RNFL analysis reveal varying stages of optic nerve appearance and optic neuropathy. This pedigree also reveals the existence of atypical early onset progressive LHON with good vision and an mt3460 mutation previously (to the authors' best knowledge) unreported in the world's literature.