Comparison of acute non-visual bright light responses in patients with optic nerve disease, glaucoma and healthy controls

Abstract

This study examined the effect of optic nerve disease, hence retinal ganglion cell loss, on non-visual functions related to melanopsin signalling. Test subjects were patients with bilateral visual loss and optic atrophy from either hereditary optic neuropathy (n = 11) or glaucoma (n = 11). We measured melatonin suppression, subjective sleepiness and cognitive functions in response to bright light exposure in the evening. We also quantified the post-illumination pupil response to a blue light stimulus. All results were compared to age-matched controls (n = 22). Both groups of patients showed similar melatonin suppression when compared to their controls. Greater melatonin suppression was intra-individually correlated to larger post-illumination pupil response in patients and controls. Only the glaucoma patients demonstrated a relative attenuation of their pupil response. In addition, they were sleepier with slower reaction times during nocturnal light exposure. In conclusion, glaucomatous, but not hereditary, optic neuropathy is associated with reduced acute light effects. At mild to moderate stages of disease, this is detected only in the pupil function and not in responses conveyed via the retinohypothalamic tract such as melatonin suppression.

Melanopsin‐mediated pupillary light reflex and sleep quality in patients with normal tension glaucoma

“…Hence, ipRGCs consist of different subtypes and have several central targets. Both studies in mouse and human have shown that it is possible that one ipRGC end-point can be affected but not another (Chen et al 2011;Munch et al 2015). Furthermore, a recent study on rat retina reported that the M1 ipRGCs are more resistant to injury than other ganglion cells following optic nerve transection (Perez de Sevilla Muller et al 2014).…”

Mood and behavior seasonality in glaucoma; assessing correlations between seasonality and structure and function of the retinal ganglion cells

“…The density of ipRGCs is, however, reduced in both primary and secondary glaucoma. Correspondingly, the NIF effects of light, specifically the sustained pupillary response to short wavelength light and the light induced suppression of pineal melatonin, are most severely affected in advanced stages of glaucoma [15][16][17]. In our population, approximately 55% had visual field defects worse than 12 dB in the better eye indicating an advanced stage of disease.…”

“…These associations may be attributable to a disrupted central light input as well as to the psychological burden of a chronic progressive disease and the threat of blindness. Indeed, there is evidence of attenuated NIF-functions in glaucoma such as reduced pupillary responses to blue light [12][13][14][15][16], reduced light induced suppression of pineal melatonin release [17] and a reduced alerting response to light [16]. These dysfunctions can all be linked to the loss of retinal ganglion cells, specifically the ipRGCs.…”

The Role of Daylight for Humans: Gaps in Current Knowledge

“…Pupil responses to light in healthy persons [167][168][169][170] and patients with eye disease [171][172][173][174][175]…”