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Documenta Ophthalmologica. Advances in... Dec 2022To develop and validate a flicker electroretinogram (ERG) protocol in term-born neonates as a potential tool for assessing preterm infants at risk of developing...
PURPOSE
To develop and validate a flicker electroretinogram (ERG) protocol in term-born neonates as a potential tool for assessing preterm infants at risk of developing retinopathy of prematurity.
METHODS
A custom flicker ERG protocol was developed for use with the hand-held RETeval® electrophysiology device. Feasibility of measuring flicker ERG through closed eyelids and without mydriasis was established in a pilot study enabling optimisation of the test protocol. Following this, healthy term-born neonates (gestational age 37-42 weeks) were recruited at the Neonatology clinic of the University Hospital Zurich. Flicker ERG recordings were performed using proprietary disposable skin electrodes during the first four days of life when the infants were sleeping. Flicker stimuli were presented at 28.3 Hz for a stimulus series at 3, 6, 12, 30, and 50 cd·s/m, with two measurements at each stimulus level. Results were analysed offline. Flicker ERG peak times and amplitudes were derived from the averaged measurements per stimulus level for each subject.
RESULTS
28 term-born neonates were included in the analysis. All infants tolerated the testing procedure well. Flicker ERG recording was achieved in all subjects with reproducible flicker ERG waveforms for 30 and 50 cd·s/m stimuli. Reproducible ERGs were recorded in the majority of infants for the weaker stimuli (with detectable ERGs in 20/28, 25/28, and 27/28 at 3, 6, and 12 cd·s/m, respectively). Flicker ERG amplitudes increased with increasing stimulus strength, with peak times concurrently decreasing slightly.
CONCLUSION
Flicker ERG recording is feasible and reliably recorded in sleeping neonates through closed eyelids using skin electrodes and without mydriasis. Flicker ERG amplitude decreases for lower luminance flicker but remains detectable for 3 cd·s/m flicker in the majority of healthy term-born neonates. These data provide a basis to study retinal function in premature infants using this protocol.
Topics: Infant, Newborn; Infant; Humans; Electroretinography; Mydriasis; Pilot Projects; Photic Stimulation; Infant, Premature; Retina
PubMed: 36199003
DOI: 10.1007/s10633-022-09889-5 -
Journal of Ophthalmic & Vision Research 2019To compare the water-drinking test (WDT) and pharmacologic mydriasis as provocative tests in patients with primary angle closure suspect (PACS). (Review)
Review
PURPOSE
To compare the water-drinking test (WDT) and pharmacologic mydriasis as provocative tests in patients with primary angle closure suspect (PACS).
METHODS
This observational non-randomized comparative study evaluated changes in intraocular pressure (IOP) in 21 patients with PACS who underwent pharmacologic mydriasis and compared it with IOP changes in 26 patients given the WDT. Ocular biometric and anterior chamber parameters were also assessed. Tests were repeated on the same patient two weeks after performing laser peripheral iridotomy (LPI).
RESULTS
The mean age standard deviation was 60 7 and 57 9 years in the mydriasis and WDT groups, respectively ( = 0.201). Before LPI, both provocative tests were associated with a significant increase in IOP (mydriasis: 15.1 3.1 to 16.6 3.5 mmHg, = 0.025; WDT: 16.2 2.8 to 18.5 3.3 mmHg, < 0.001). However, the IOP changes were not statistically different between groups ( = 0.102). After LPI, only the WDT group showed a continued significant IOP elevation after the test (mydriasis: 16.4 3.3 to 16.7 3.5 mmHg, = 0.569; WDT: 14.9 3.0 to 17.8 4.1 mmHg, < 0.001). The post-test IOP change was significantly greater in the WDT than in the mydriasis group (3.0 versus 0.3 mmHg, respectively; = 0.002). Step-wise multiple regression analysis verified the type of provocative test as the only independent factor affecting the post-test IOP change after LPI (regression coefficient: 2.664; = 0.002).
CONCLUSION
Pharmacologic mydriasis and the WDT had similar IOP elevation before LPI, but after LPI, IOP elevation was much greater in the WDT group.
PubMed: 31660105
DOI: 10.18502/jovr.v14i3.4782 -
Medical Science Monitor : International... Mar 2022Adie's pupil, also called tonic pupil, is mainly seen in young women. Most patients have unilateral eye involvement. The pupil of the affected side is significantly... (Review)
Review
Adie's pupil, also called tonic pupil, is mainly seen in young women. Most patients have unilateral eye involvement. The pupil of the affected side is significantly larger than that on the healthy side. The direct and indirect light reflection from the pupil on the affected side disappears. The pupil on the affected side is sensitive to low concentrations of pilocarpine. The pathogeneses of Adie's pupil are complex, some of which are insidious and lack corresponding specific diseases. Through a literature review, we found that Adie's pupil is mainly associated with infectious diseases, most commonly syphilis, followed by immune diseases and paraneoplastic syndromes. The ophthalmological symptoms and pupil abnormalities can disappear after active treatment of the primary disease. Pilocarpine can be used to treat ophthalmologic symptoms, such as blurred vision, for which patients might visit an ophthalmologist or neurologist. It is essential for clinicians to improve their understanding of the disease to avoid misdiagnosis. Differential diagnosis between Adie's pupil, oculomotor nerve palsy, anticholinergic drug overdose, Argyll-Robertson pupil, and congenital mydriasis need to be identified by the physician. Here, the clinical manifestations, pathogenesis, relationship between Adie's pupil and diseases, and differential diagnosis of Adie's pupil are reviewed.
Topics: Adie Syndrome; Diagnosis, Differential; Humans; Physicians; Pupil; Tonic Pupil
PubMed: 35304432
DOI: 10.12659/MSM.934657 -
Clinical Genetics Sep 1977Routine ophthalmoscopy and fundoscopy of 673 individuals revealed 42 whose irides failed to dilate to a clinically useful degree within 25 to 30 min after the...
Routine ophthalmoscopy and fundoscopy of 673 individuals revealed 42 whose irides failed to dilate to a clinically useful degree within 25 to 30 min after the administration of drops of 1% mydracil. These individuals occurred with different frequency among the Aymara, Mestizo, and non-Aymara groups which made up the sample of examinees. The phenomenon was most common among the Aymara, less common among the Mestizos, and least common among the non-Aymara. Distribution of affected individuals within the three groups suggests that the trait is inherited.
Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Chile; Eye Color; Female; Fundus Oculi; Genetics, Medical; Humans; Indians, South American; Infant; Infant, Newborn; Male; Middle Aged; Mydriatics; Ophthalmoscopy; Pupil
PubMed: 908166
DOI: No ID Found -
Journal of Ophthalmology 2016Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons... (Review)
Review
Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis) without affecting the accommodative ability of the eye (cycloplegia) could be useful in many clinical and research contexts. Phenylephrine hydrochloride (PHCl) is a sympathomimetic agent that is used clinically to dilate the pupil. Nevertheless, first investigations suggested some loss of functional accommodation in the human eye after PHCl instillation. Subsequent studies, based on different measurement procedures, obtained contradictory conclusions, causing therefore an unexpected controversy that has been spread almost to the present days. This manuscript reviews and summarizes the main research studies that have been performed to analyze the effect of PHCl on the accommodative system and provides clear conclusions that could help clinicians know the real effects of PHCl on the accommodative system of the human eye.
PubMed: 28053778
DOI: 10.1155/2016/7968918 -
Internal Medicine (Tokyo, Japan) 2017A 40-year-old woman with bipolar disorder who was taking mirtazapine presented with mydriasis, abnormal diaphoresis, myoclonus and muscle rigidity after taking...
A 40-year-old woman with bipolar disorder who was taking mirtazapine presented with mydriasis, abnormal diaphoresis, myoclonus and muscle rigidity after taking metocloplamide. Her medical history, which included the use of serotonergic agents, and the presence of symptoms including myoclonus and muscle rigidity were consistent with a diagnosis of serotonin syndrome (SS) according to the Hunter criteria. The symptoms diminished following three days of treatment with oral lorazepam and cyproheptadine and a reduced dose of mirtazapine. Metoclopramide is frequently used to various gastric symptom. Metoclopramide is not widely known to induce SS. This potentially fatal condition should be avoided by exercising care in the use of drugs that have the potential to cause drug-drug interactions.
Topics: Adult; Antiemetics; Bipolar Disorder; Drug Interactions; Female; Humans; Metoclopramide; Mianserin; Mirtazapine; Serotonin Syndrome; Selective Serotonin Reuptake Inhibitors
PubMed: 28321081
DOI: 10.2169/internalmedicine.56.7727 -
Trends in Hearing 2018In recent years, the fields of Audiology and Cognitive Sciences have seen a burgeoning of research focusing on the assessment of the effort required during listening....
In recent years, the fields of Audiology and Cognitive Sciences have seen a burgeoning of research focusing on the assessment of the effort required during listening. Among approaches to this question, the pupil dilation response has shown to be an informative nonvolitional indicator of cognitive processing during listening. Currently, pupillometry is applied in laboratories throughout the world to assess how listening effort is influenced by various relevant factors, such as hearing loss, signal processing algorithms, cochlear implant rehabilitation, cognitive abilities, language competency, and daily-life hearing disability. The aim of this special issue is to provide an overview of the state of the art in research applying pupillometry, guidance for those considering embarking on pupillometry studies, and to illustrate the diverse ways in which it can be used to answer-and raise-pertinent research questions.
Topics: Attention; Audiometry; Auditory Perception; Cognition; Female; Hearing Loss; Humans; Male; Mydriasis; Pupil; Reaction Time; Signal-To-Noise Ratio; Speech Intelligibility; Speech Perception
PubMed: 30208763
DOI: 10.1177/2331216518799437 -
Scientific Reports Nov 2016Diabetic retinopathy (DR) is a leading cause of blindness among working-age adults. Therefore, it is important to detect DR accurately during mass screening. The purpose... (Clinical Trial)
Clinical Trial
Diabetic retinopathy (DR) is a leading cause of blindness among working-age adults. Therefore, it is important to detect DR accurately during mass screening. The purpose of this study was to determine whether a small, hand-held, mydriasis-free, full-field flicker electroretinographic (ERGs) device called RETeval can be used to screen for DR. To accomplish this, we recorded full-field flicker ERGs with this device from 48 normal eyes and 118 eyes with different severities of DR in patients with diabetes mellitus (DM). This system delivered a constant flash retinal luminance by adjusting the flash luminance that compensated for changes in the pupil size. Our results showed that there were significant correlations between the severity of DR and the implicit times (P < 0.001; r = 0.55) and the amplitudes (P = 0.001; r = -0.29). When the implicit time was used for the index, the area under the receiver operating characteristic curve was 0.84 for the detection of DR, and was 0.89 for the detection of DR requiring ophthalmic treatments. These results suggest that the implicit times of the flicker ERGs recorded by the small, mydryasis-free ERG system can be used as an adjunctive tool to screen for DR.
Topics: Adult; Diabetic Retinopathy; Electroretinography; Female; Humans; Male; Middle Aged; Prospective Studies; Retina
PubMed: 27824158
DOI: 10.1038/srep36591 -
Ophthalmic Research 2019The aim of this article was to describe recent advances in the use of new technology in diabetic retinopathy screening by looking at studies that assessed the... (Review)
Review
PURPOSE
The aim of this article was to describe recent advances in the use of new technology in diabetic retinopathy screening by looking at studies that assessed the effectiveness and cost-effectiveness of these technologies.
METHODS
The author conducts an ongoing search for articles relating to screening or management of diabetic retinopathy utilising Zetoc with keywords and contents page lists from relevant journals.
RESULTS
The areas discussed in this article are reference standards, alternatives to digital photography, area of retina covered by the screening method, size of the device and hand-held cameras, mydriasis versus non-mydriasis or a combination, measurement of distance visual acuity, grading of images, use of automated grading analysis and cost-effectiveness of the new technologies.
CONCLUSIONS
There have been many recent advances in technology that may be adopted in the future by screening programmes for sight-threatening diabetic retinopathy but each device will need to demonstrate effectiveness and cost-effectiveness before more widespread adoption.
Topics: Diabetic Retinopathy; Global Health; Humans; Incidence; Mass Screening; Photography; Retina; Visual Acuity
PubMed: 31132764
DOI: 10.1159/000499539 -
Arquivos Brasileiros de Oftalmologia 2023Cycloplegia is crucial for reliable pediatric ophthalmology examinations. This document provides a re-commendation for pediatric cycloplegia and mydriasis for Brazilian...
Cycloplegia is crucial for reliable pediatric ophthalmology examinations. This document provides a re-commendation for pediatric cycloplegia and mydriasis for Brazilian ophthalmologists. This article was developed based on literature reviews; the clinical experience of Brazilian specialists, as obtained through questionnaires; and the consensus of the Expert Committee of the Brazilian Pediatric Ophthalmology Society. According to the best evidence and formulations available in Brazil, this committee recommends the use of one drop of 1% cyclopentolate plus one drop of 1% tropicamide in children older than 6 months and two drops of 1% tropicamide 0-5 minutes apart for those younger than 6 months. Mydriasis may be increased by a single drop of 2.5% phenylephrine. For retinopathy of prematurity screening, the recommendation is 0.5% or 1% tropicamide, administered two or three times, 5 minutes apart, and 2.5% phenylephrine, used preferably once. In all scenarios, we recommend the use of a prior drop of 0.5% proxymetacaine.
PubMed: 35319660
DOI: 10.5935/0004-2749.20230049