In vivo identification of morphologic retinal abnormalities in neuromyelitis optica

Abstract

We have identified a pattern of retinal morphologic abnormalities in NMO that is associated with severe retinal axonal and neuronal loss and corresponding visual disability. MME may contribute to poor visual outcomes following NMO-associated ON or alternatively represent a marker of ON severity. Additionally, our results support that subclinical involvement of the anterior visual pathway may occur in NMO spectrum disorders.

Retrograde Maculopathy in Patients With Glaucoma

“…The correlation with severity may also help to understand the variable MME prevalence previously reported in different types of optic neuropathies. Some optic neuropathies, including neuromyelitis optica, cause more severe optic atrophy and have a prevalence of MME up to 30%, 14,22 while more moderate optic neuropathies, such as those in MS, have a lower prevalence of about 4%. 23 We found a frequency of MME of 3% in the glaucoma group, while we previously found a prevalence of 8% in nonglaucomaassociated optic neuropathy.…”

“…11 Nerve fiber damage and the subsequent retrograde loss of ganglion cells is thought to cause a dysfunction of Muller cells, which impairs retinal water clearance and results in edema. [12][13][14][15] Muller cell gliosis is indeed a common finding in animal models of optic neuropathy 16,17 and in humans. 18 MME has been found in all types of optic neuropathy including glaucoma, 19 with a reported prevalence of 4% in the latter and 9% in nonglaucoma optic neuropathies.…”

The Clinical Spectrum of Microcystic Macular Edema

“…3 Recent studies predominantly have focused on MME in multiple sclerosis 1,4,5 and neuromyelitis optica (NMO). 6,7 It was suggested that MME originated from breakdown of the bloodretinal barrier or focal inflammation. 1 However, microcystic changes in the INL were also described in compressive optic neuropathy (due to glioma), 8 Leber's hereditary optic neuropathy, dominant optic atrophy, 9 and endemic optic neuropathy, 10 suggesting retrograde trans-synaptic degeneration from optic neuropathy as a causative factor for degeneration of the INL with formation of cystic spaces.…”

Formation of Macular Inner Nuclear Layer Cysts in Optic Atrophy

“…Subsequent reports noted similar cysts in other types of inflammatory optic neuropathies. 8,9 Balk et al 10 and Sotirchos et al 11 hypothesized that INL cysts were the product of an immune response against aquaporin-4 channel found on Müller cells. Their theory was supported by animal models in which deletion of aquaporin-4 led to induction of retinal inflammation and decreased capacity of Müller cells to regulate osmotic stress.…”

“…Therefore, Barboni et al 2 offered a hypothesis based on vitreous traction rather than transsynaptic degeneration, since transsynaptic degeneration would be expected to occur in all eyes over a sufficient period of time, and yet these cysts are not seen in all eyes. 10 They highlighted the importance of an attached posterior hyaloid membrane preventing the collapse of the INL and proposed that the spaces that previously were occupied by the now degenerated cells became fluid filled spaces.…”