AUTHOR=La Morgia Chiara , Carelli Valerio , Carbonelli Michele 

TITLE=Melanopsin Retinal Ganglion Cells and Pupil: Clinical Implications for Neuro-Ophthalmology

JOURNAL=Frontiers in Neurology

VOLUME=Volume 9 - 2018

YEAR=2018

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2018.01047

DOI=10.3389/fneur.2018.01047

ISSN=1664-2295

ABSTRACT=Melanopsin retinal ganglion cells (mRGCs) are intrinsically photosensitive RGCs that mediate many relevant non-image forming functions of the eye, including the pupillary light reflex, through the projections to the olivary pretectal nucleus.
In particular, the post-illumination pupil response (PIPR), as evaluated by chromatic pupillometry, can be used as a reliable marker of mRGC function in vivo. In the last years, pupillometry has become a promising tool to assess mRGC dysfunction in various neurological and neuro-ophthalmological conditions. In this review we will present the most relevant findings of pupillometric studies in various neuro-ophthalmological conditionsincluding hereditary optic neuropathies, glaucoma, ischemic optic neuropathies, idiopathic intracranial hypertension, multiple sclerosis and Parkinson’s disease. The use of PIPR as a marker for mRGC function is also proposed for other neurodegenerative disorders in which circadian dysfunction is documented.