Influence of macular pigment on the sensitivity to discomfort glare from daylight.

Understanding the factors that influence the human perception of glare is necessary to properly address glare risks in buildings and achieve comfortable visual environments, especially in the workplace. Yet large inter-individual variabilities in glare perception remain unexplained and thus uncovered by the current empirical glare models. We hypothesize that this variability has an origin in the human retina, in particular in the density of macular pigments present in its central area, which varies between individuals.

Pathogenesis of Vascular Retinal Manifestations in Patients: A Review.

Pandemic infection secondary to coronavirus disease 2019 () had an important impact on the general population affecting not only respiratory tract but also many other organs. Ocular manifestations are quite common at the level of the anterior segment (conjunctivitis, dry eye), while posterior segment and, in particular, retinal findings are less frequent. In the retina, is associated with vascular events.

Susac Syndrome: A Case Series.

Background: Susac syndrome (SS) is an autoimmune disorder that involves the eyes, the brain, and the ears. It is a rare cause of recurrent branch retinal artery occlusion. The purpose of this study was to report cases of SS, highlighting the clinical presentations, therapeutic options, and their outcome.

Quantification of the early pupillary dilation kinetic to assess rod and cone activity.

Rods, cones and melanopsin contribute in various proportions, depending on the stimulus light, to the pupil light response. This study used a first derivative analysis to focus on the quantification of the dynamics of pupillary dilation that immediately follows light-induced pupilloconstriction in order to identify novel parameters that reflect rod and cone activity. In 18 healthy adults, the pupil response to a 1 s blue light stimulus ranging from - 6.

Case Report: A Novel Mutation in the Mitochondrial Gene Is Associated With Leber Hereditary Optic Neuropathy (LHON).

Leber hereditary optic neuropathy (LHON) is a mitochondrial disease causing severe bilateral visual loss, typically in young adults. The disorder is commonly caused by one of three primary point mutations in mitochondrial DNA, but a number of other rare mutations causing or associated with the clinical syndrome of LHON have been reported. The mutations in LHON are almost exclusively located in genes encoding subunits of complex I in the mitochondrial respiratory chain.

Can Extra Daytime Light Exposure Improve Well-Being and Sleep? A Pilot Study of Patients With Glaucoma.

Glaucoma damages retinal ganglion cells, including intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells modulate various non-visual physiological and psychological functions which are modulated by light. In patients with glaucoma, we assessed the effect of daily bright light exposure (LE) on several melanopsin-dependent functions, such as the pupil constriction, circadian rest-activity cycles, sleep and subjective well-being including relaxation, alertness and mood.

Update in the Management of Idiopathic Intracranial Hypertension.

Idiopathic intracranial hypertension is a syndrome of increased intracranial pressure of unknown cause that most often occurs in women of childbearing age. Most patients are overweight or obese with a history of recent weight gain. Following a brief review of the symptoms and signs, we discuss the approach to assessment and monitoring of this condition.

Early-Stage Alzheimer's Disease Does Not Alter Pupil Responses to Colored Light Stimuli.

Background: Pathologic changes in cerebral and retinal structures governing the pupillary light reflex occur in Alzheimer's disease (AD). Analysis of pupillary responses originating from different retinal cells may allow for non-invasive detection of cerebral AD pathology.

Objective: This study aimed to quantify the pupil light reflex using a portable chromatic pupillometer in patients with early stage AD and compare their responses to those of a healthy control group.

The Tadpole Pupil: Case Series With Review of the Literature and New Considerations.

Tadpole pupil is a rare phenomenon in which segmental spasm of the iris dilator muscle results in a tadpole-shaped pupil. The pupillary distortion is usually unilateral, lasts several minutes, and can recur in clusters. Any segment of the iris can be affected; thus, for some patients, a different-shaped tadpole pupil is noticed from episode to episode.

Maturation of the Pupil Light Reflex Occurs Until Adulthood in Mice.

With respect to photoreceptor function, it is well known that electroretinogram (ERG) amplitudes decrease with age, but to our knowledge, studies describing age-related changes in the pupil light response (PLR) of mice are lacking. This study recorded the PLR and ERG in C57BL/6 and Sv129S6 wild-type mice at three different ages during early adulthood. Dark- and light-adapted PLR and ERG measurements were performed at 1, 2, and 4 months of age.

Chromatic Pupillometry in Children.

Chromatic pupillometry is a technique that is increasingly used to assess retinal disorders. As age may be one of the various factors which can influence the pupillary light reaction, this study aimed to evaluate the pupil responses to colored light stimuli in the pediatric population. Fifty-three children with normal vision and without any history of ocular disorders were tested with a portable pupillometer.

Distinct modes of stress granule assembly mediated by the KH-type RNA-binding protein Rnc1.

We have previously identified the KH-type RNA-binding protein Rnc1 as an important regulator of the posttranscriptional expression of the MAPK phosphatase Pmp1 in fission yeast. Rnc1 localization in response to stress has not been elucidated thus far. Here, we report the dual roles of Rnc1 in assembly of stress granules (SGs), nonmembranous cytoplasmic foci composed of messenger ribonucleoproteins.

Invited Commentary: Evaluation of Horner Syndrome in the MRI Era.

Unlabelled: This Invited Commentary discusses the following article: BACKGROUND:: To identify the etiologies of adult Horner syndrome (HS) in the MRI era using a targeted evaluation approach and to assess the value and yield of targeted imaging.

Methods: A retrospective chart review was performed of 200 adult outpatients with HS, confirmed with cocaine eyedrop testing. Patients were divided into subgroups based on the presence or absence of symptoms and those who did or did not receive additional testing with hydroxyamphetamine drops.

International Consensus Statement on the Clinical and Therapeutic Management of Leber Hereditary Optic Neuropathy.

Leber hereditary optic neuropathy (LHON) is currently estimated as the most frequent mitochondrial disease (1 in 27,000-45,000). Its molecular pathogenesis and natural history is now fairly well understood. LHON also is the first mitochondrial disease for which a treatment has been approved (idebenone-Raxone, Santhera Pharmaceuticals) by the European Medicine Agency, under exceptional circumstances because of the rarity and severity of the disease.

Melanopsin-Mediated Acute Light Responses Measured in Winter and in Summer: Seasonal Variations in Adults with and without Cataracts.

Seasonal adaptation is a ubiquitous behavior seen in many species on both global hemispheres and is conveyed by changing photoperiods. In humans this seasonal adaptation is less apparent, in part because changes in daylength are masked by the use of electrical lighting at night. On the other hand, cataracts which reduce light transmission, may compound seasonal changes related to the reduced daylength of winter.

Optical Coherence Tomography to Differentiate Papilledema from Pseudopapilledema.

Purpose Of Review: Mild papilledema may be difficult to distinguish by clinical observation from pseudopapilledema. An accurate diagnosis is critical to avoid invasive workup and unwarranted treatment. In this review, we focus on the development and subsequent role of optical coherence tomography (OCT) in detecting and differentiating optic nerve head drusen (ONHD) from papilledema and other causes of acquired swelling of the optic disc.

frees mice from the repression of active wake behaviors by light.

Besides its role in vision, light impacts physiology and behavior through circadian and direct ( 'masking') mechanisms. In Smith-Magenis syndrome (SMS), the dysregulation of both sleep-wake behavior and melatonin production strongly suggests impaired non-visual light perception. We discovered that mice haploinsufficient for the SMS causal gene, (), were hypersensitive to light such that light eliminated alert and active-wake behaviors, while leaving time-spent-awake unaffected.