Changes in Choroidal Thickness follow the RNFL Changes in Leber’s Hereditary Optic Neuropathy

Abstract

Leber’s hereditary optic neuropathy (LHON) is typically characterized by vascular alterations in the acute phase. The aim of this study was to evaluate choroidal changes occurring in asymptomatic, acute and chronic stages of LHON. We enrolled 49 patients with LHON, 19 with Dominant Optic Atrophy (DOA) and 22 healthy controls. Spectral Domain-Optical Coherence Tomography (SD-OCT) scans of macular and peripapillary regions were performed in all subjects, to evaluate macular and peripapillary choroidal thickness, and retinal nerve fiber layer (RNFL) thicknes. Macular and peripapillary choroidal thicknesses were significantly increased in the acute LHON stage. On the contrary, macular choroidal thickness was significantly reduced in the chronic stage. Furthermore, peripapillary choroidal thickness was decreased in chronic LHON and in DOA. Both RNFL and choroid had the same trend (increased thickness, followed by thinning), but RNFL changes preceded those affecting the choroid. In conclusion, our study quantitatively demonstrated the involvement of the choroid in LHON pathology. The increase in choroidal thickness is a feature of the LHON acute stage, which follows the thickening of RNFL. Conversely, thinning of the choroid is the common outcome in chronic LHON and in DOA.

Peripapillary vessel density changes in Leber's hereditary optic neuropathy: a new biomarker

“…The present results, it should be noted, do not parallel our recent findings regarding choroidal thickness changes seen in LHON . This previous publication demonstrated that the RNFL and choroid in LHON underwent an increase in thickness, followed by permanent thinning, and the RNFL changes preceded those affecting the choroid.…”

Choroidal thickness and the retinal ganglion cell complex in chronic Leberʼs hereditary optic neuropathy: a prospective study using swept-source optical coherence tomography

“…Three mitochondrial mutations at nucleotide positions m.11778G > A, m.3460G > A m.11484T > C result in defective subunit expression of complex I protein in the electron transport chain, and account for ~90% of LHON cases [ 4 – 8 ]. Characteristic patterns of retinal nerve fibre layer (RNFL) thickening from nerve fibre swelling in early or acute stages of LHON followed by RNFL thinning from decreased nerve fibre swelling in late or chronic stages of LHON have been observed [ 9 – 11 ]. Acute LHON has been characterized by significant nerve fibre thickening in the superior and inferior quadrants followed later by swelling of nasal fibres, while in chronic LHON there is differential preservation of the nasal nerve fibres [ 4 – 6 ].…”

“…Aside from these structural nerve fibre changes, optical coherence tomography (OCT) studies have also suggested vascular pathology in LHON. Our laboratory recently demonstrated that RNFL thickening in acute LHON is accompanied by choroidal thickening, and RNFL thinning in chronic LHON is similarly accompanied by choroidal thinning [ 11 ]. This study also showed a direct correlation between RNFL and choroidal thicknesses in LHON, suggesting that RNFL thickness may be associated with changes in the choroid [ 11 ].…”

Treatment strategies for Leber hereditary optic neuropathy

“…LHON typically presents with unilateral, painless, subacute, central visual loss with the fellow eye becoming involved within the following 6 months [10  ]. In about 25% of cases, there is simultaneous involvement of both optic nerves at first presentation [2,11]. An international consensus statement has defined 3 clinical stages in LHON based on the time from onset of visual loss, namely subacute (< 6months), dynamic (6 -12 months) and chronic (> 12 months) [12  ].…”