Good to see our animal work repeated in humans

Klistorner A, Graham EC, Yiannikas C, Barnett M, Parratt J, Garrick R, Wang C, You Y, Graham SL.
Progression retinal ganglion cell loss in multiple sclerosis is associated with new lesions in the optic radiations. Eur J Neurol. 2017 Aug 10. doi: 10.1111/ene.13404. [Epub ahead of print]

BACKGROUND: The mechanism of retinal ganglion cell (RGC) and retinal nerve fibre layer (RNFL) loss in multiple sclerosis (MS) remains unknown. This study aims to investigate the association between temporal RNFL (tRNFL) thinning and disease activity in the brain determined by T2 lesions on MRI.

METHODS: 55 consecutive relapsing-remitting MS (RRMS) patients and 25 controls were enrolled. All patients underwent annual optical coherence tomography (OCT) and high-resolution MRI scans for tRNFL thickness and brain lesion volume analysis, respectively.

RESULTS: Significant tRNFL thickness reduction was observed over the 3-year follow-up period at a relatively constant rate (1.02 μm per year). Thinning of tRNFL fibers was more prominent in younger patients (p = 0.01). The tRNFL loss was associated with new MRI lesions in the optic radiations (OR). There was significantly greater tRNFL thinning in patients with new lesional activity in OR compared to patients with new lesions outside of OR (p = 0.009).

CONCLUSIONS: This study supports the notion that retrograde transneuronal degeneration caused by optic radiation lesions might play a role in progressive RNFL loss.

The visual system is the most accessible, it is often used in MS to assess the effects of MS. Most recently it is being studied with optical coherence tomography (OCT). You shine a light beam in the eye and it reflects light back and it gives a picture of the eye. It's like an ultrasound of the eye but using light rather than sound.

A few years ago we made some mice that had retinal cells that glowed in the dark and the mice also got inflammation of the optic nerve.

Neuroprotection in a Novel Mouse Model of Multiple Sclerosis Katie Lidster, Samuel J. Jackson, Zubair Ahmed, Peter Munro, Pete Coffey, Gavin Giovannoni, Mark D. Baker, David Baker PLoS One. 2013; 8(11): e79188.

It showed us that damage to the optic pathway resulted in die-back of the nerve and the retinal ganglion cell died and disappeared a few days later.

This causes thinning of the retina, and a loss in retinal nerve thickness layer, so I'm not sure why this abstract starts the way it does as there are hundreds of animal studies showing retrograde loss of retinal nerves after damage nerves between the eye and the brain. So good to see when they look in humans they find the same thing happens.

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