Macular nerve fibre and ganglion cell layer changes in acute Leber's hereditary optic neuropathy

Abstract

AimsTo evaluate longitudinal retinal ganglion cell inner plexiform layer (GC-IPL) and macular retinal nerve fibre layer (mRNFL) thickness changes in acute Leber's hereditary optic neuropathy (LHON).MethodsSix eyes of four patients with LHON underwent SD-OCT (optical coherence tomography) at month 1, 3, 6 and 12 after visual loss. In two eyes, the examination was carried out in the presymptomatic stage. The relationship and curves for area under the receiver operator characteristic (AUROC) were generated to assess the ability of each parameter to detect ganglion cell loss.ResultsSignificant longitudinal thinning of GC-IPL and mRNFL was detected in LHON. GC-IPL thinning was detectable in the deviation map during the presymptomatic stage in the inner ring of the nasal sector and then it progressively extended following a centrifugal and spiral pattern. Similarly, mRNFL thinning began in the inferonasal sector and it progressively extended. No further statistically significant changes were detected after month 3. The highest level of AUROC values at 1 month were detected in the nasal sectors and inferonasal mRNFL thickness reached AUROC value=1. All the parameters were equally able to detect ganglion cell loss from month 2 to 12.ConclusionsThe natural history of GC-IPL thinning follows a specific pattern of reduction, reflecting the anatomical course of papillomacular fibres. Month 6 represents the end of GC-IPL loss. GC-IPL and mRNFL thinning is detectable before onset of visual loss. These observations can help future therapeutic approaches for both LHON carriers at high risk of conversion and patients with acute early LHON.

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

“…The natural history of peripapillary RNFL changes throughout the different LHON phases has been quantitatively described81819. Our study confirmed a thickening occurring in RNFL layer inferior-temporally, in LHON mutation carriers.…”

“…Recently, SD-OCT has been instrumental in the qualitative and quantitative assessment of funduscopic changes over the natural history of LHON81819. Nevertheless, OCT studies have been focused on measuring RNFL and RGC thickness, whereas the vascular changes remained neglected and poorly evaluated.…”

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

“…This study reveals significant peripapillary microvascular changes over the different stages of disease progression in patients affected by LHON. The changing pattern of RNFL and GC‐IPL is consistent with previous works . The key finding is that microvascular changes in the temporal sector, implicating the papillomacular bundle, precede the RNFL and mirror the GC‐IPL changes.…”

A neurodegenerative perspective on mitochondrial optic neuropathies

“…Interestingly, in patients presenting with first eye involvement, the macular ganglion cell and inner plexiform layer (GC-IPL) and the macular RNFL already showed pathological thinning in the presymptomatic stage about 6 weeks before the onset of visual loss in the fellow eye. Maximal GC-IPL thinning was reached by 6 months and this OCT parameter could, therefore, prove to be a more sensitive biomarker of optic nerve damage compared with peripapillary RNFL measurements where progressive thinning continues until at least 12 months after the first onset of visual loss [14]. …”