Background: To compare objective electrophysiological contrast sensitivity function (CSF) in patients implanted with either multifocal intraocular lenses (MIOLs) or monofocal intraocular lenses (IOLs) by pattern reversal visual evoked potentials (prVEP) measurements.
Methods: Fourty-five cataract patients were randomly allocated to receive bilaterally: apodized diffractive-refractive Alcon Acrysof MIOL (A), full diffractive AMO Tecnis MIOL (B) or monofocal Alcon Acrysof IOL (C). Primary outcomes: 1-year differences in objective binocular CSF measured by prVEP with sinusoid grating stimuli of 6 decreasing contrast levels at 6 spatial frequencies. Secondary outcomes: psychophysical CSF measured with VCTS-6500, photopic uncorrected distance (UDVA), and mesopic and photopic uncorrected near and intermediate visual acuities (UNVA and UIVA respectively).
Results: Electrophysiological CSF curve had an inverted U-shaped morphology in all groups, with a biphasic pattern in Group B. Group A showed a lower CSF than group B at 4 and 8 cpd, and a lower value than group C at 8 cpd. Psychophysical CSF in group A exhibited a lower value at 12 cpd than group B. Mean photopic and mesopic UNVA and UIVA were worse in monofocal group compared to the multifocal groups. Mesopic UNVA and UIVA were better in group B.
Conclusions: Electrophysiological CSF behaves differently depending on the types of multifocal or monofocal IOLs. This may be related to the visual acuity under certain conditions or to IOL characteristics. This objective method might be a potential new tool to investigate on MIOL differences and on subjective device-related quality of vision.
Abstract: The article discusses the early abandonment of mechanical theories about eye enlargement in degenerative myopia at the turn of the 20th century. At that time, the number of theories about myopia grew unrestricted, but with scant support from the experimental field. The mechanical theories vanished as a new wave of metabolism-based theories appeared, propelled by the huge advances in molecular biology. Modern techniques allow reconsidering those theories and to put them to test with higher confidence.
Background: The ORVIS infrastructure aims to facilitate the development and availability of valid and adapted tools that will allow functional, perceptual, cognitive and psychological evaluation of low vision clients by researchers and clinicians who work in low vision and visual impairment rehabilitation.
Methods: The tools developed or documented within ORVIS Infrastructure are tests or questionnaires which allow, or will allow to assess—in an accurate and reliable manner—characteristics related to visual impairment. The tools in development are: (I) questionnaire de repérage des hallucinations visuelles liées au syndrome de Charles-Bonnet (QR-SCB); (II) repérage des personnes agées présentant des INDices de déficience VISUELle (IndiVisuel); (III) mesure de l’impact de la déficience visuelle dans les activités quotidiennes (MIDVAQ) and (IV) M’EYE read test. The directory documents 14 tools and offers—within a descriptive sheet—characteristics, components and metrological properties as supported by cited scientific studies.
Results: The ORVIS Infrastructure, which aims at the development and availability of assessment tools, fills researchers’ and clinicians’ needs for measurement tools that are valid, effective and appropriate for use with a visually impaired clientele. Such tools are, especially in French, little known and hard to find, and represent a precious resource for those who want to evaluate the efficacy of treatments or interventions.
Conclusions: ORVIS is available at www.orvis.vision. Between November 2015 and September 2017, the directory has been accessed 1,383 times by 952 unique visitors.
Background: With a large portion of older adults living longer, the number of individuals diagnosed with low vision is increasing. The use of optical coherence tomography/scanning laser ophthalmoscope (OCT/SLO) to diagnose retinal disease has become common place in the last 10 years, yet currently there are no OCT/SLO databases for pathological vision. Our aim is to develop a clinical database of individuals who have drusen (i.e., lipid deposits found under the retina), or have been diagnosed with age-related macular degeneration (AMD), with information as to how the structure of the diseased retina changes over time, as well as measures of visual and cognitive functional performance.
Methods: Fundus photographs and retinal scans will be taken using the same model of optos OCT/SLO located in three test sites (MAB-Mackay Rehabilitation Centre, School of Optometry Clinic at the University of Montreal, and the Lighthouse Institute, New York, USA). For each individual entry in the database, demographic and diagnosis information will be available. All OCT/SLO images will be graded according to the Age-related Eye Disease Study standard, in addition to number and size of drusen, severity of geographic atrophy, severity of pigment mottling and presence of choroidal neovascularization. Retinal topography and Raster scans from the OCT/SLO will provide a cross-sectional look at affected retinas. Fixation stability will be recorded using the SLO function, and present four different tasks that are designed to reproduce typical tasks of daily vision, with each task lasting for 10 seconds. The tasks are cross fixation, face recognition, visual search, and reading. These tasks in addition to the retinal scans will be used to determine the eccentricity of a preferred retinal locus from the anatomical fovea, and can be used as an outcome measure for clinical interventions in visually impaired patients.
Results: The database will be available to professors training eye-care practitioners and rehabilitation specialists as a teaching tool. Students will be able to familiarize themselves with the retina and a variety of AMD-related pathologies before they start working with patients. The database will also be accessible by researchers interested in studying AMD from basic science to epidemiology, to investigate how drusen and AMD impact visual and cognitive functional performance.
Conclusions: The common infrastructure is easily accessible to all VHRN members on request. The database will also be accessible online in 2018 (see http://cvl.concordia.ca for more information).
Background: Dementia is a syndrome that affects a person’s ability to understand and express information. The higher prevalence of vision and/or hearing losses among persons with dementia in long-term care (LTC) facilities interferes with the ability of nurses to provide optimal care because communication is compromised. Therefore, the detection and screening for sensory impairment is of the utmost importance in LTC facilities; however, there is currently no agreement among nursing professionals on how to best identify such losses for the purpose of further referral, and the need for a validated screening measure suitable for nurses in LTC facilities is clear. The present project aims to close this gap by investigating the screening recommendations of vision- and hearing-care professionals working with clients affected by dementia.
Methods: Eleven experts in audiology, optometry, deafblindness, and technology participated in individual semi-structured interviews on the topic of tools and strategies that can be used to screen individuals with dementia for sensory loss. Interview transcripts were coded by two evaluators using verbal agreement and consensus building.
Results: Three main themes emerged from the interviews with experts: barriers, facilitators, and strategies. Barriers to sensory screening were often mentioned, particularly impaired communication and lack of staff cooperation. Facilitators consisted uniquely of people, such as family members, intervenors, and nurses. Strategies for sensory screening in this population consisted of improving communication through repetition and encouragements; considerations based on familiarity; and inferring an impairment on the basis of patient behaviour. Few of our interviewees were knowledgeable on the topic of screening apps.
Conclusions: Our findings, to be integrated with a similar environmental scan conducted among LTC nurses, can inform the administration of sensory impairment screening tests among a population with dementia in order to optimize care.
Background: A growing number of older adults with vision loss require vision rehabilitation services to address reading difficulties. Braille may be the most appropriate option for those with functional blindness, poor visual prognoses or dual sensory loss. While standardized braille assessment and training protocols are in place to guide interventions with children, there is a high degree of inconsistency and a lack of evidence-based knowledge about best practices to use with adults and seniors who require braille training. Age-related declines in tactile acuity, motor dexterity and cognition present unique barriers to braille training, but very little is known about the impact of aging on factors related to braille reading performance. The aim of this scoping review is to identify the perceptual, motor, and cognitive factors related to braille reading performance and to determine how these factors have been assessed or measured among blind adults and elderly individuals in prior studies.
Methods: Using the scoping review method, a comprehensive search was conducted in three databases: PubMed, Educational Resource Information Center (ERIC), and the Cochrane library. Two reviewers screened articles for inclusion to ensure internal agreement, based on identified exclusion criteria.
Results: The initial search resulted in 1,565 qualitative and quantitative articles. The results synthesize the perceptual, motor and cognitive factors known to predict braille reading performance, how these variables are impacted by the aging process, and how they have been measured in prior studies.
Conclusions: This scoping review is the first step in working towards the development of evidence-based assessment and training protocols to standardized practice with adult and senior clients who require braille training. It also serves to clarify where current knowledge gaps exist in order to guide future studies on braille reading and aging.
Background: (I) To describe the development and components of the automobile simulator driving behavior evaluation system developed by CRIR-Institut Nazareth et Louis-Braille; (II) to present the preliminary results of the content evaluation of the driving behavior evaluation grid.
Methods: The evaluation system consists of five components: (I) the VS500M Car Simulator (Virage Simulation); (II) four VS500M driving scenarios, modified to minimize the occurrence of simulator sickness and expose subjects to commonly encountered driving situations on highways and city boulevards; (III) the Tobii Pro Glasses 2 eye tracking device; (IV) a car simulator driving behavior observation grid (DBOG); (V) a software application used during the behaviour evaluation phase, where synchronized video tracking, certain data from the simulator (e.g., speed) and the DBOG grid are presented. Initially, the expected safe driving behaviors were identified, including 235 of a visual nature, supported by literature data and consultation of the project steering committee and an expert in driving assessment. Driving behaviors were assessed in 22 subjects without visual impairment (mean age 55±20 years). Subsequently, the items were revised to determine their relevance based on their importance in terms of road safety or on the frequency with which behaviors were observed among participants. For analysis purpose, the items of the DBOG were grouped according to their content, by type of expected driving behavior (e.g., following a stop, look to the left and right before crossing the intersection) or element to be detected (e.g., pedestrians).
Results: Some visual behaviors are difficult to observe with the eye tracker device because they are more dependent on peripheral than central vision. Others are rarely observed, possibly because they are little or not realized in daily life or the representation of reality on the simulator does not stimulate their adoption. On the other hand, the visual detection behaviors expected in a situation where safety can be compromised are mostly carried out (e.g., detection of oncoming vehicles, side mirror verification when changing lanes).
Conclusions: This first phase of the study has made possible to better target the items to be kept in the car simulator driving behavior observation grid, and those that will have to be removed as they are too difficult to observe or too rarely adopted by the participants. Content validity and inter-rater reliability will be assessed from the simplified grid.
Background: This infrastructure delivers biological material necessary for several research projects to Vision Health Research Network investigators (VHRN).
Methods: Héma-Québec is the organism in charge obtaining consent and retrieving donor eyes for patient treatment or for research. In Quebec City, donor eyes are sent to the eye bank of the “Centre Universitaire d’Ophtalmologie” (CUO) of Saint-Sacrement hospital. Technicians at the eye bank evaluate the quality of the tissues. Those unfit for graft are transferred to the infrastructure where the coordinator encodes samples prior to their distribution.
Results: Between 2013 and 2017, 27 fundamental investigators, clinical investigators and collaborators supported by 60 students, trainees and laboratory assistants used this infrastructure to move forward their projects. Since 2013, results from those projects generated 21 scientific publications and 232 presentations. The infrastructure helped VHRN investigators obtain near 4 million dollars in grants from many organisms (CIHR, NSERC, Foundations, etc.). These grants allowed recruitment and formation of highly qualified personnel. Last year (April 2016 to March 2017), 189 corneas and 23 eyes transited through the infrastructure.
Conclusions: This infrastructure is available for all investigators that are members of the VHRN. Many original projects have been elaborated thanks to the human ocular tissues provided by this infrastructure. These projects will advance our knowledge in vision health. A better understanding of eye functions will lead to new treatments for eye diseases.
