B-mode ultrasound assessment of pupillary function: Feasibility, reliability and normal values

PLoS ONE, Год журнала: 2017, Номер 12(12), С. e0189016 - e0189016

Опубликована: Дек. 6, 2017

To evaluate B-mode ultrasound as a novel method for the examination of pupillary function and to provide normal values reflex assessed by ultrasound.100 subjects (49 female, 51 male, mean [range] age [18-80 years]) with no history ophthalmologic disease, clinically detectable defects, corrected visual acuity ≥ 0.8 were included in this prospective observational study. was performed eyes closed using an Esaote-Mylab25 system according current guidelines orbital insonation. A standardized light stimulus applied.The ± standard deviation left right diameters (PD) at rest 4.7 4.5 mm. Following ipsilateral (Lstim), constricted PD 2.8 0.6 2.7 contralateral Lstim, 2.6 0.5 Left constriction time (PCT) following Lstim 970 261.6 967 220 ms. PCT 993.8 192.6 963 189.4 Patient inversely correlated after (all p<0.001), but not PCT.B-mode is simple, rapid objective quantitative assessment function, which may prove useful variety settings where eyelid retraction impeded or infrared pupillometry device unavailable.

Язык: Английский

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Melanopsin-Driven Pupil Response and Light Exposure in Non-seasonal Major Depressive Disorder

Frontiers in Neurology, Год журнала: 2018, Номер 9

Опубликована: Сен. 13, 2018

Background: Melanopsin-expressing intrinsically photosensitive Retinal Ganglion Cells (ipRGCs) signal non-imaging forming effects of environmental light for circadian phoentrainment, the pupil reflex, and mood regulation. In seasonal affective disorder, ipRGC dysfunction is thought to cause abberant transmission external illumination photoentrainment. It not known if patients with non-seasonal depression have abnormal melanospin mediated signaling and/or irregular exposure. Methods: Twenty-one adults who live in a sub-tropical region, including eight thirteen age-matched healthy controls were recruited. The Mini International Neuropsychiatry Interview diagnosed presence major depressive disorder. Light exposure was determined using actigraphy over 2 week period. melanopsin post-illumination response (PIPR) outer retinal inputs ipRGCs (transient maximum constriction amplitude) measured 1 s, short long wavelength high low excitation. Results: mean daylight as function clock hours total duration (mins) levels commonly recommended therapy significantly different between groups. Out 84 measurements (42 each control groups), melanopsin-mediated PIPR amplitude, transient response, amplitude Conclusions: This report provides initial evidence normal exposures pre-dominately mid moderate subtropical location southern hemisphere.

Язык: Английский

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Outer Retinal Structure and Function Deficits Contribute to Circadian Disruption in Patients With Type 2 Diabetes

Investigative Ophthalmology & Visual Science, Год журнала: 2019, Номер 60(6), С. 1870 - 1870

Опубликована: Май 1, 2019

Purpose: Light transmitted by retinal photoreceptors provides the input for circadian photoentrainment. In diabetes, there is a high prevalence of and sleep disruption but underlying causes are not well understood. Patients with diabetes can exhibit dysfunctional their role in health known. Here we quantify photoreceptor function contributions to patients without diabetic retinopathy healthy controls. Methods: Rod, cone, melanopsin was derived using chromatic pupillometry 47 participants including 23 type 2 24 age-matched controls after an ophthalmic examination thickness assessment optical coherence tomography. Circadian determined dim light melatonin onset (DLMO) questionnaires; exposure measured actigraphy. Results: Compared control group, had significantly earlier DLMO (1 hour) (P = 0.008), higher subjective scores < 0.05), reduction pupil constriction amplitude red stimuli 0.039) early postillumination response (PIPR) blue 0.024) stimuli. There were no between-group differences pattern, activity levels, intrinsic melanopsin-mediated PIPR > 0.05). A significant correlation evident between outer (r −0.65, P 0.03) 0.63, 0.03); thinner retina lower amplitudes. Conclusions: We infer that observed changes due structural functional rod deficits at stage eye disease.

Язык: Английский

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Handheld chromatic pupillometry can accurately and rapidly reveal functional loss in glaucoma

British Journal of Ophthalmology, Год журнала: 2021, Номер 107(5), С. 663 - 670

Опубликована: Дек. 1, 2021

Background/aims Early detection and treatment of glaucoma can delay vision loss. In this study, we evaluate the performance handheld chromatic pupillometry (HCP) for objective rapid functional loss in glaucoma. Methods clinic-based, prospective enrolled 149 patients (median (IQR) years: 68.5 (13.6) years) with confirmed 173 healthy controls (55.2 (26.7) years). Changes pupil size response to 9 s exponentially increasing blue (469 nm) red (640 light-stimuli were assessed monocularly using a custom-built pupillometer. Pupillometric features extracted from individual traces compared between groups. Features highest classification potential, selected gradient boosting machine technique, incorporated into generalised linear model classification. Receiver operating characteristic curve analyses (ROC) used compare HCP, optical coherence tomography (OCT) Humphrey Visual Field (HVF). Results Pupillary light responses altered controls. For classification, HCP yielded an area under ROC (AUC) 0.94 (95% CI 0.91 0.96), sensitivity 87.9% specificity 88.4%. The early-moderate (visual field mean deviation (VFMD) > -12 dB; AUC=0.91 0.87 0.95)) was similar HVF (AUC=0.91) reduced OCT (AUC=0.97; p=0.01). severe (VFMD ≤ dB), had excellent (AUC=0.98, 95% 0.97 1) that OCT. Conclusion allows accurate, glaucomatous eyes different severities.

Язык: Английский

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Effect of Single and Combined Monochromatic Light on the Human Pupillary Light Response

Frontiers in Neurology, Год журнала: 2018, Номер 9

Опубликована: Ноя. 29, 2018

The pupillary light reflex (PLR) is a neurological driven by rods, cones, and melanopsin-containing retinal ganglion cells. Our aim was to achieve more precise picture of the effects 5-min duration monochromatic stimuli, alone or in combination, on human PLR, determine its spectral sensitivity assess importance photon flux. Using pupillometry, PLR assessed 13 participants (6 women) aged 27.2 ± 5.41 years (mean±SD) during stimuli purple (437nm), blue (479nm), red (627nm), combinations red+purple red+blue light. In addition, nine 5-min, photon-matched ranging 10nm increments peaking between 420 500nm were tested 15 (8 25.7±8.90 years. Maximum pupil constriction, time this, constriction velocity, area under curve (AUC) at short (0-60s) longer (240-300s) exposures, 6-s post-illumination response (6-s PIPR) assessed. Photoreceptor activation estimated mathematical modelling. velocity significantly faster with than Within spectrum (between 500nm), 480nm stimulus, while slowest observed 430nm achieved 470nm light, greatest AUC0-60 AUC240-300 490 460nm respectively. PIPR maximum after 490nm stimulus. Both transient (AUC0-60) sustained (AUC240-300) correlated melanopic activation. Higher fluxes for both produced greater amplitude constriction. findings confirm dependence wavelength, bichromatic flux stimuli. Since most rapid high occurred within 460-490nm range (alone combined), our results suggest that colour discrimination should be studied total partial substitution this (460-490nm) shorter wavelengths (∼440nm). Thus nocturnal lighting, replacement might plausible solution preserve minimizing

Язык: Английский

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