Prevalence, associated risk factors; and patient and economic impact of multiple sensory impairment in a multi-ethnic elderly population in Singapore: the PIONEER study.

BACKGROUND: To determine the prevalence, risk factors; and impact on patient health and economic outcomes across the laterality spectrum of multiple sensory impairment (MSI) in a multi-ethnic older Asian population. METHODS: In this population-based study of Singaporeans aged ≥ 60 years, MSI was defined as concomitant vision (visual acuity > 0.3 logMAR), hearing (pure-tone air conduction average > 25 dB), and olfactory (score < 12 on the Sniffin' Sticks test) impairments across the spectrum of laterality (any, unilateral, combination [of unilateral and bilateral], and bilateral). RESULTS: Among 2,057 participants (mean ± SD 72.2 ± 0.2 years; 53.1% female), the national census-adjusted prevalence rates of any, unilateral, combination, and bilateral MSI were 20.6%, 1.2%, 12.2%, and 7.2%, respectively. Older age, male gender, low socioeconomic status (SES), and smoking (all p < 0.05) were independently associated with higher likelihood of any MSI. Compared to those with no sensory loss, those with MSI had significantly decreased mobility (range 5.4%-9.2%), had poor functioning (OR range 3.25-3.45) and increased healthcare costs (range 4-6 folds) across the laterality spectrum. Additionally, bilateral MSI had a significant decrease in HRQoL (5.5%, p = 0.012). CONCLUSIONS: MSI is a highly prevalent medical condition, with 1 in 5; and almost 1 in 10 community-dwelling older Asians having any and bilateral MSI, respectively, with a higher likelihood in men, smokers, and those with low SES. Critically, MSI has a substantial negative impact on patient health and economic outcomes across the laterality spectrum. Sensory testing is critical to detect and refer individuals with MSI for management to improve their functional independence and QoL.

Does using a bioptic telescope improve visual recognition of the on-road environment?

SIGNIFICANCE: Individuals with reduced visual acuity (VA) may drive with bioptic telescopes in some jurisdictions. The effect of bioptic telescope use on on-road recognition distances is important for driving safety, as increased recognition distances increase the time available to react to road signs or driving events. PURPOSE: This study aimed to investigate the impact of bioptic telescope use on visual recognition of road signs, traffic lights, and hazards in an on-road driving environment in individuals with reduced VA. METHODS: Ten individuals (mean ± standard deviation age, 39.1 ± 19.1 years) with reduced VA (trained to use bioptic telescopes) participated in a repeated-measures on-road experiment for two viewing conditions, with and without a bioptic telescope (randomized order). Participants underwent a clinical low vision assessment, including high-contrast VA with and without the bioptic telescope aligned, visual fields, and contrast sensitivity testing. For the driving component, participants seated in the front passenger seat of a moving car reported all road signs, traffic lights, and hazards (unpredictable road events that represent a risk to driving safety including other vehicles, cyclists, pedestrians) seen along a route that included suburban roads and highways. Video cameras captured participants' viewing behavior, verbal commentary, and the distance at which three pre-selected road signs were reported. RESULTS: In the eye with the bioptic telescope, high-contrast VA improved from 0.75 ± 0.17 (without) to 0.25 ± 0.1 logMAR with the bioptic telescope. Bioptic telescope use did not affect the percentage of road signs, traffic lights, or hazards correctly recognized but did result in 2.6 times longer recognition distances (49 ± 23 vs. 19 ± 11 m, t9 = 5.02, p<0.001). CONCLUSIONS: Road signs were recognized at significantly longer distances when using a bioptic telescope, confirming their positive impact on timely visual recognition of objects within the driving scene. Future work should explore whether this effect generalizes to individuals using bioptic telescopes when driving a vehicle.

Hyperopia in schoolchildren: Investigating the impact on vision and determining appropriate methods for screening.

INTRODUCTION: Hyperopia is associated with reduced vision and educational outcomes in schoolchildren. This study explored the impact of clinically significant hyperopia (≥+2.00 D) on visual function in schoolchildren and compared the ability of different screening tests (alone and in combination) to detect this level of hyperopia. METHODS: Vision testing including monocular logMAR visual acuity (VA) measured to threshold (distance [DVA], near [NVA] and DVA through a plus lens [+2.50 D]), stereoacuity and cycloplegic autorefraction (tropicamide 1%) were undertaken on 263 schoolchildren (mean age: 11.76 years ± 3.38) in Queensland, Australia. Vision measures were compared between children with clinically significant hyperopia in at least one meridian (≥+2.00 D) and emmetropia/low hyperopia (>0.00 and <+2.00 D). Receiver operating curve (ROC) analysis was performed to identify optimal pass/fail criteria for each test and the diagnostic accuracy of individual and combinations of tests. RESULTS: Thirty-two children had clinically significant hyperopia and 225 had emmetropia/low hyperopia. DVA and NVA were worse (p < 0.01), while the difference in DVA through a plus lens was less in children with clinically significant hyperopia (p < 0.01). ROC analysis for individual tests resulted in areas under the curve (AUCs) ranging from 0.65 to 0.85. Combining screening tests revealed that failing one or more of the following tests was most effective for detecting hyperopia: DVA, NVA and difference in DVA through a plus lens, resulting in a sensitivity and specificity of 72% and 81%, respectively. CONCLUSION: Significant differences in visual function existed between schoolchildren with clinically significant hyperopia and emmetropia/low hyperopia. Combining measures of DVA and NVA and the difference in DVA through a plus lens demonstrated good discriminative ability for detecting clinically significant hyperopia in this population.

Effect of low luminance on face recognition in adults with central and peripheral vision loss.

PURPOSE: To investigate the effect of low luminance on face recognition, specifically facial identity discrimination (FID) and facial expression recognition (FER), in adults with central vision loss (CVL) and peripheral vision loss (PVL) and to explore the association between clinical vision measures and low luminance FID and FER. METHODS: Participants included 33 adults with CVL, 17 with PVL and 20 controls. FID and FER were assessed under photopic and low luminance conditions. For the FID task, 12 sets of three faces with neutral expressions were presented and participants asked to indicate the odd-face-out. For FER, 12 single faces were presented and participants asked to name the expression (neutral, happy or angry). Photopic and low luminance visual acuity (VA) and contrast sensitivity (CS) were recorded for all participants and for the PVL group, Humphrey Field Analyzer (HFA) 24-2 mean deviation (MD). RESULTS: FID accuracy in CVL, and to a lesser extent PVL, was reduced under low compared with photopic luminance (mean reduction 20% and 8% respectively; p < 0.001). FER accuracy was reduced only in CVL (mean reduction 25%; p < 0.001). For both CVL and PVL, low luminance and photopic VA and CS were moderately to strongly correlated with low luminance FID (ρ = 0.61-0.77, p < 0.05). For PVL, better eye HFA 24-2 MD was moderately correlated with low luminance FID (ρ = 0.54, p = 0.02). Results were similar for low luminance FER. Together, photopic VA and CS explained 75% of the variance in low luminance FID, and photopic VA explained 61% of the variance in low luminance FER. Low luminance vision measures explained little additional variance. CONCLUSION: Low luminance significantly reduced face recognition, particularly for adults with CVL. Worse VA and CS were associated with reduced face recognition. Clinically, photopic VA is a good predictor of face recognition under low luminance conditions.

The relationship between central and mid-peripheral motion perception and the hazard perception test in younger and older adults.

INTRODUCTION: Vision standards for driving are typically based on visual acuity, despite evidence that it is a poor predictor of driving safety and performance. However, visual motion perception is potentially relevant for driving, as the vehicle and surroundings are in motion. This study explored whether tests of central and mid-peripheral motion perception better predict performance on a hazard perception test (HPT), which is related to driving performance and crash risk, than visual acuity. Additionally, we explored whether age influences these associations, as healthy ageing impairs performance on some motion sensitivity tests. METHODS: Sixty-five visually healthy drivers (35 younger, mean age: 25.5; SD 4.3 years; 30 older adults, mean age: 71.0; SD 5.4 years) underwent a computer-based HPT, plus four different motion sensitivity tests both centrally and at 15° eccentricity. Motion tests included minimum displacement to identify motion direction (Dmin ), contrast detection threshold for a drifting Gabor (motion contrast), coherence threshold for a translational global motion stimulus and direction discrimination for a biological motion stimulus in the presence of noise. RESULTS: Overall, HPT reaction times were not significantly different between age groups (p = 0.40) nor were maximum HPT reaction times (p = 0.34). HPT response time was associated with motion contrast and Dmin centrally (r = 0.30, p = 0.02 and r = 0.28, p = 0.02, respectively) and with Dmin peripherally (r = 0.34, p = 0.005); these associations were not affected by age group. There was no significant association between binocular visual acuity and HPT response times (r = 0.02, p = 0.29). CONCLUSIONS: Some measures of motion sensitivity in central and mid-peripheral vision were associated with HPT response times, whereas binocular visual acuity was not. Peripheral testing did not show an advantage over central testing for visually healthy older drivers. Our findings add to the growing body of evidence that the ability to detect small motion changes may have potential to identify unsafe road users.

Low levels of refractive blur increase the risk of colour misperception of red train signals.

PURPOSE: Red signals signify danger in a range of situations, including train operations. Importantly, misperception of a red signal as yellow can have serious safety implications. This study investigated the effects of lens blur on incorrect colour perception of red signals, which has been implicated in previous train crashes. METHODS: Participants included 15 young (26.6 ± 4.6 years) and 15 older (55.8 ± 3.1 years) visually normal adults. Red and yellow wayside train signals were simulated for two brightness levels (dim, bright) using a custom-built projection system. The effect of blur (best-corrected refraction [No Blur], +0.25 DS, +0.50 DS, +0.75 DS, +1.00 DS, +1.25 DS) on the number of incorrect colour perception responses of the signals was recorded. The order of conditions was randomised between participants. RESULTS: For incorrect responses to the red signal, there were significant main effects of blur (p < 0.001) and signal brightness (p < 0.001) and a significant interaction between blur and brightness (p < 0.001). The effects of blur were greater for the dim compared to the bright signals, with significantly higher colour misperceptions for the dim signal for +0.50 DS blur and higher, compared with No Blur. Colour misperceptions of the yellow signals were low compared with that of the red signals, with only +1.25 DS blur resulting in a significantly higher number of incorrect responses than No Blur (p < 0.001). There were no effects of age for the red or yellow colour misperceptions (p > 0.19). CONCLUSIONS: Low levels of blur (+0.50 DS to +1.25 DS) resulted in a significant misperception of the red signals as orange-yellow, particularly for dim signals. The findings have implications for vision testing and refractive correction of train drivers to minimise the possibility of colour misperception of red train signals.

High Rates of Uncorrected Vision Conditions among Schoolchildren in Rural Queensland, Australia.

SIGNIFICANCE: This study is the first to report high rates of uncorrected vision conditions among Australian secondary schoolchildren living in a rural area and to comment on the rate of eye examinations undertaken on Australian Indigenous children. Uncorrected vision problems that continue throughout the school years have significant implications for children's quality of life and education. PURPOSE: This study aimed to investigate the prevalence of uncorrected vision conditions among Australian schoolchildren. METHODS: Participants included 280 students from rural primary and secondary schools (aged 4 to 18 years), of whom 40% identified as being of Aboriginal and/or Torres Strait Islander descent (Indigenous). All participants underwent an eye examination including measurements of monocular distance and near visual acuity, assessment of accommodative and vergence function, stereoacuity, color vision, and cycloplegic autorefraction. A parental questionnaire was used to determine whether the child had previously had his/her eyes examined. RESULTS: The overall prevalence of uncorrected vision conditions in this population was 35%. The odds of previously having had an eye examination were 2.3× higher for non-Indigenous compared with Indigenous children despite both groups exhibiting high rates of uncorrected vision conditions (Indigenous, 31 [29%]; non-Indigenous, 66 [40%]; χ21 = 3.24, P = .07). Of the children who had significant refractive error (Indigenous, 23 [21%]; non-Indigenous, 49 [30%]; χ21 = 2.70, P = .10), 82% were uncorrected, and only 39% of Indigenous children and 54% of non-Indigenous children had previously had an eye examination. CONCLUSIONS: These findings suggest that high rates of uncorrected vision conditions are present among Australian primary and secondary schoolchildren from a rural area and highlight that Indigenous children are much less likely to have had an eye examination. Understanding factors that affect the rate of eye examinations and compliance with spectacle correction must be addressed given the potential impact of these vision conditions.

Motion perception at mesopic light levels: effects of physiological ageing and eccentricity.

PURPOSE: To explore the differential effects of age and eccentricity on the perception of motion at photopic and mesopic light levels. METHODS: Thirty-six visually normal participants (18 younger; mean age 25 years, range: 20-31) and (18 older; mean age 70 years, range: 60-79) underwent two testing sessions, one at photopic and one at mesopic light levels. In each session, motion perception was tested binocularly at two eccentricities (centrally, and peripherally at 15° rightwards and 5° superior to the horizontal) for four motion tasks: minimum contrast of a drifting Gabor to identify motion direction (motion contrast); translational global motion coherence; biological motion embedded in noise and the minimum duration of a high-contrast Gabor to determine the direction of motion, using two Gabor sizes to measure spatial surround suppression of motion. RESULTS: There was a significant main effect of light condition (higher thresholds in mesopic) for motion contrast (p < 0.001), translational global motion (p = 0.001) and biological motion (p < 0.001); a significant main effect of age (higher thresholds in older adults) for motion contrast (p < 0.001) and biological motion (p = 0.04) and a significant main effect of eccentricity (higher thresholds peripherally) for motion contrast (p < 0.001) and biological motion (p < 0.001). Additionally, we found a significant three-way interaction between light levels, age and eccentricity for translational global motion (similar increase in mesopic thresholds centrally for both groups, but a much larger deterioration in older adult's peripheral mesopic thresholds, p = 0.02). Finally, we found a two-way interaction between light condition and eccentricity for translational global motion (higher values in central mesopic relative to peripheral photopic, p = 0.001) and for biological motion (higher values in peripheral mesopic relative to central photopic, p < 0.001). CONCLUSIONS: For the majority of tasks assessed, motion perception was reduced in mesopic relative to photopic conditions, to a similar extent in both age groups. However, because some older adults exhibited elevated thresholds even under photopic conditions, particularly in the periphery, the ability to detect mesopic moving stimuli even at high contrast was markedly impaired in some individuals. Our results imply age-related differences in the detection of peripheral moving stimuli at night that might impact hazard avoidance and night driving ability.

Determinants of concern about falling in adults with age-related macular degeneration.

PURPOSE: To investigate the prevalence and level of concern about falling (CF) among older people with vision impairment due to age-related macular degeneration (AMD) compared to a visually normal control group, and to identify determinants of CF for the AMD group. METHODS: Participants included 133 older people: 77 with AMD (mean age = 80.5 ± 6.2 years), and 56 controls (mean age = 75.4 ± 5.3 years). Binocular visual acuity, contrast sensitivity and visual fields were measured, and CF was assessed using the Falls Efficacy Scale - International (FES-I). Data were also collected for sensorimotor function (postural sway, sit-to-stand, knee extensions, walking speed, proprioception), and neuropsychological function (reaction time, symptoms of anxiety and depression) using validated tests and scales. RESULTS: Concern about falling scores were higher for AMD participants compared to control participants (mean ± S.D. 24.6 ± 8.0 vs 21.6 ± 5.7, p = 0.02, respectively), although these findings failed to reach significance when adjusted for age (p = 0.16). Among AMD participants, multivariable models showed that greater CF was associated with reduced contrast sensitivity (p = 0.02), slower sit-to-stand times (p < 0.001) and higher anxiety scores (p < 0.001); these factors explained 40% of the variance in CF (p < 0.01). CONCLUSION: Levels of CF in older people with AMD were not found to be elevated by their disease status alone, but rather by the extent of vision loss. Levels of CF in those with AMD were associated with various visual, sensorimotor and neuropsychological factors. These findings will assist clinicians in identifying those at greatest risk of developing high CF and inform the design of future intervention programmes for this population.

The effect of low light levels on postural stability in older adults with age-related macular degeneration.

PURPOSE: To investigate the effect of low light levels on postural stability in older adults with and without age-related macular degeneration (AMD). METHODS: Participants included 28 older adults [14 with AMD (mean age ± S.D., 83.4 ± 6.7 years) and 14 controls with normal vision (74.6 ± 3.3 years)]. Postural stability was assessed with eyes open on both a firm and foam surface under four lighting conditions in a randomised order: photopic (~436 lux, vertically at the eye), sudden reduction to mesopic (~436 to ~1 lux), adapted mesopic (~1 lux) and adapted mesopic with a light emitting diode (LED) door frame lighting system (~1.3 lux), using the root mean square (RMS) of the centre of pressure measures derived from an electronic force plate in the anterior-posterior (AP) and medio-lateral (ML) directions. Visual function was assessed binocularly (visual acuity, contrast sensitivity and visual fields), physical function was assessed using standardised measures (sit-to-stand, grip strength and the timed walk test) and self-reported difficulties under low light levels were recorded using the Low Luminance Questionnaire. Data were analysed using linear mixed models. RESULTS: For all participants, low light levels significantly increased postural sway on the foam surface in the AP (p = 0.01) but not ML (p = 0.80) direction, but had no effect on postural stability on the firm surface. On the foam surface, while AP-RMS sway was significantly greater in the sudden (p < 0.001) and adapted (p = 0.02) mesopic compared to the photopic condition, sway for the adapted mesopic with the LED lighting system was not significantly different to the photopic condition (p = 0.20). On the foam surface, AP-RMS (p = 0.02) and ML-RMS (p < 0.001) sway were significantly greater in the AMD compared to the control group. None of the measures of visual function was significantly associated with AP- or ML-RMS sway. CONCLUSIONS: On the foam surface, low light levels significantly reduced postural stability in older adults with and without AMD, and postural stability was significantly reduced for the AMD group compared to controls, regardless of light level. Importantly, the LED lighting system reduced sway under mesopic conditions, which was not significantly greater than that measured under photopic conditions in either group. These findings have important implications for enhancing the visual environment for older adults with and without AMD to improve postural stability and reduce the risk of falls in low lighting environments.

Eye movement patterns and reading ability in children.

PURPOSE: Eye movements are integral to the reading process. This study characterised the eye movement patterns of children differentiated by their reading ability, while completing a saccadic eye movement test with irregular target spacing (Development Eye Movement (DEM) test) using a novel eye movement classification algorithm. METHODS: Participants included 196 Grade 2 Australian schoolchildren (mean age: 7.9 ± 0.3 years) who completed a computerised version of the DEM test, while their eye movements were recorded (Tobii TX300 eye-tracker). Children also completed a standardised reading comprehension test, which categorised them into below average and average or above reading ability groups. A novel eye movement classification algorithm was developed that considered the vertical and horizontal eye movements of each child. RESULTS: Compared to children with average or above reading ability, the below average reading group displayed poor vertical eye movement control, demonstrated by a significantly greater proportion of interline eye movements (vertical eye movements away from the current line) (p < 0.001). Differences in horizontal eye movements were also observed, with below average readers demonstrating a smaller proportion of expected forward saccades (p < 0.001) (within-line forward saccades with horizontal amplitude between the minimum and maximum horizontal spacing between digits), while this group also displayed longer fixation durations (p = 0.001). The below average reading group demonstrated significantly poorer results on all standard DEM metrics than the average or above reading ability group: horizontal subtest time (p < 0.001), vertical subtest time (p = 0.004) and ratio (p = 0.004). CONCLUSIONS: Children exhibiting below average reading ability were poorer at maintaining control of vertical (interline), as well as horizontal, eye movements compared to children with average or above reading ability. Future studies should explore the mechanisms underlying these differences, particularly in vertical eye movements, given that reading paragraphs (involving multiple lines of text) requires accurate eye movements in both the vertical and horizontal direction.

The mental health and wellbeing survey of Australian optometrists.

PURPOSE: To investigate the prevalence of mental health conditions and burnout among practising optometrists in Australia. METHODS: A cross-sectional survey of registered practising Australian optometrists was undertaken over a three-week period from mid-November 2019. The survey comprised three well-established mental health scales (Kessler Psychological Distress Scale [K10], Depression Anxiety Stress Scales [DASS-21] and Maslach Burnout Inventory [MBI]) and an open-ended question inviting comments. RESULTS: Five hundred and five respondents completed the K10, representing 8.8% of registered optometrists in Australia; 466 completed all three scales. Prevalence of moderate to severe psychological distress (K10 ≥ 25) was 30.7% (95% CI 26.7%-34.7%), with similar findings for depression and anxiety (DASS-21). Prevalence of high burnout, as indicated by MBI-GS exhaustion was 56.1% (95% CI 51.7%-60.4%), cynicism 57.1% (95% CI 52.7%-61.5%) and professional efficacy 23.1% (95% CI 19.4%-26.8%). Optometrists aged ≤ 30 years were 3.5 times more likely to report moderate to severe psychological distress compared to optometrists aged >30 years (OR = 3.54, P < 0.001, 95% CI 2.38-5.25). The most frequently mentioned work-related issues concerned retail pressures, workload and career dissatisfaction. CONCLUSIONS: The rates of mental health conditions and burnout reported by practising Australian optometrists were high compared with the general population and other health professionals. Younger age and burnout were significant risk factors for psychological distress. Interventions are required to address these issues, particularly for younger optometrists, and could include workplace modifications and building resilience to improve personal mental wellbeing and ensure patient safety.

Refractive blur affects judgement of pedestrian walking direction at night.

PURPOSE: Many individuals drive with uncorrected refractive errors, which has implications for night driving, where poor visibility contributes to the increased crash risk relative to daytime. This study explored how small amounts of refractive blur affects the judgment of the walking direction of night-time pedestrians and whether different types of retro-reflective clothing influence this effect. METHODS: Judgement of the walking direction of night-time pedestrians was investigated for 20 young participants with normal vision (mean age, 21.8 ± 1.6 years) for two levels of binocular blur (+0.50DS, +1.00DS) compared to baseline (best-corrected refractive correction). Participants seated in a stationary car with low beam headlamps observed a pedestrian wearing three clothing conditions: retro-reflective vest (1) and retro-reflective biomotion clothing (incorporating thin (2) or thick (3) retro-reflective strips), who walked across the road in three directions (straight across, away or towards the car). The order of conditions was randomised among participants. Participants reported the perceived pedestrian walking direction and how confident they rated their response. Outcome measures included the proportion of correct responses (response accuracy) and confidence ratings. RESULTS: Blur had a significant effect on accuracy in judging pedestrian walking direction; accuracy decreased significantly with increasing blur (p < 0.001), with all blur levels being significantly different from one another. The effect of pedestrian clothing was also significant (p < 0.001); direction judgements were least accurate for vest, followed by both thin and thick biomotion, where accuracy judgements were similar. There was also a significant interaction between blur and clothing (p < 0.05). Similar trends were found for confidence ratings across the blur and clothing conditions. Greater confidence was significantly associated with increased response accuracy for the biomotion clothing, but not the vest. CONCLUSION: Findings highlight that even small amounts of blur (+0.50DS), that do not reduce visual acuity below the legal driving limits, reduce the ability to accurately judge pedestrian walking direction at night. Retro-reflective clothing in a biomotion configuration facilitated the highest accuracy and confidence in judgment of pedestrian walking direction, for both thin and thick strips compared to vest, for all blur levels.

Nighttime driving: visual, lighting and visibility challenges.

PURPOSE: Nighttime driving is dangerous and is one of the most challenging driving situations for most drivers. Fatality rates are higher at night than in the day when adjusted for distances travelled, particularly for crashes involving pedestrians and cyclists. Although there are multiple contributory factors, the low light levels at night are believed to be the major cause of collisions with pedestrians and cyclists at night, most likely due to their reduced visibility. Understanding the visibility problems involved in nighttime driving is thus critical, given the increased risk to road safety. RECENT FINDINGS: This review discusses research that highlights key differences in the nighttime road environment compared to the day and how this affects visual function and driving performance, together with an overview of studies investigating how driver age and visual status affect nighttime driving performance. Research that has focused on the visibility of vulnerable road users at nighttime (pedestrians and cyclists) is also included. SUMMARY: Collectively, the research evidence suggests that visual function is reduced under the mesopic lighting conditions of night driving and that these effects are exacerbated by increasing age and visual impairment. Light and glare from road lighting and headlights have significant impacts on vision and night driving and these effects are likely to change with evolving technologies, such as LED streetlighting and headlights. Research also highlights the importance of the visibility of vulnerable road users at night and the role of retroreflective clothing in the 'biomotion' configuration for improving their conspicuity and hence safety.

Experiences following cataract surgery - patient perspectives.

PURPOSE: Most patients report being highly satisfied with the outcome of cataract surgery but there are variable reports regarding the impact of cataract surgery on some real-world activities, such as fall rates. We hypothesised that adaptations to changed refractive correction and visual function may cause difficulties in undertaking everyday activities for some patients and used a series of focus groups to explore this issue. METHOD: Qualitative methods were used to explore patients' experiences of their vision following cataract surgery, including adaptation to vision changes and their post-surgical spectacle prescription. Twenty-six participants took part in five focus groups (Mean age = 68.2 ± 11.4 years), and the data were analysed using thematic analysis. RESULTS: We identified three themes. 'Changes to Vision' explores participants' adaptation following cataract surgery. While several had problems with tasks relying on binocular vision, few found them bothersome and they resolved following second eye surgery. Participants described a trial and error approach to solving these problems rather than applying solutions suggested by their eyecare professionals. 'Prescription Restrictions' describes the long-term vision problems that pre-surgery myopic patients experienced as a consequence of becoming emmetropic following surgery and thus needing spectacles for reading and other close work activities, which they did not need before surgery. Very few reported that they had the information or time to make a decision regarding their post-operative correction. 'Information Needs' describes participant's responses to the post-surgical information they were given, and the unmet information need regarding when they can drive following surgery. CONCLUSION: The findings highlight the need for clinicians to provide information on adaptation effects, assist patients to select the refractive outcome that best suits their lifestyle, and provide clear advice about when patients can start driving again. Patients need to be provided with better guidance from clinicians and prescribing guidelines for clinicians would be beneficial, particularly for the period between first- and second-eye surgery.

Impact of glaucoma on executive function and visual search.

PURPOSE: Executive function and visual search are linked to a number of activities of daily living including driving and mobility. Using a computerised version of the Trail Making Test B (TMT-B), we compared the executive function and visual search ability of older adults with glaucoma to age-similar controls and identified which visual function tests best predict TMT-B performance. Novel low-contrast and shifting-target variations of the test were incorporated to explore the effects of different levels of test complexity. METHODS: Thirty-one older adults with mild to moderate glaucoma (mean age = 71.2 years [SD 6.9]; better-eye mean deviation [MD]: median = -1.9 dB [IQR = -1.2 to 0.4], worse-eye MD: median = -11.1 dB [IQR = -14.0 to -7.7]) and 24 age-similar controls (mean age = 71.9 years [SD 6.6]) with normal vision participated. The groups were matched in age, sex, and cognitive status (mini-mental state examination [MMSE]). Participants underwent measurements of visual acuity, contrast sensitivity (CS), visual fields, and visual processing speeds using the useful field-of-view (UFoV). Participants then completed four variations of a computerised TMT-B test, with different levels of complexity based on target contrast (high/low-contrast) and shifts in target position (fixed/shifting locations). Linear mixed-effect models were used to explore the effects of group, target contrast and shift on TMT-B completion time. RESULTS: The glaucoma group took 17.3s longer than controls to complete the TMT-B (P = 0.028). All participants took 6.5s longer to complete the low- compared to the high-contrast tests (P = 0.012), and 10.6s longer for the shifting TMT-B compared to the fixed version (P < 0.001). There was no interaction effect between group, contrast, or target shift on completion time. Across all tests and participant groups, longer completion time was associated with slower UFoV processing speeds (divided attention: P = 0.003; selective attention: P = 0.006). Poorer CS was associated with longer completion times for the low (P = 0.007), but not the high-contrast tests. CONCLUSIONS: Our findings suggest that older adults with mild to moderate glaucoma have poorer visual search ability and executive function relative to controls. However, decreasing target contrast or shifting target position did not exacerbate the effects of glaucomatous visual impairment on performance. The UFoV was a strong predictor of TMT-B performance.

Differential aging effects in motion perception tasks for central and peripheral vision.

The perception of motion is considered critical for performing everyday tasks, such as locomotion and driving, and relies on different levels of visual processing. However, it is unclear whether healthy aging differentially affects motion processing at specific levels of processing, or whether performance at central and peripheral spatial eccentricities is altered to the same extent. The aim of this study was to explore the effects of aging on hierarchically different components of motion processing: the minimum displacement of dots to perceive motion (Dmin), the minimum contrast and speed to determine the direction of motion, spatial surround suppression of motion, global motion coherence (translational and radial), and biological motion. We measured motion perception in both central vision and at 15° eccentricity, comparing performance in 20 older (60-79 years) and 20 younger (19-34 years) adults. Older adults had significantly elevated thresholds, relative to younger adults, for motion contrast, speed, Dmin, and biological motion. The differences between younger and older participants were of similar magnitude in central and peripheral vision, except for surround suppression of motion, which was weaker in central vision for the older group, but stronger in the periphery. Our findings demonstrate that the effects of aging are not uniform across all motion tasks. Whereas the performance of some tasks in the periphery can be predicted from the results in central vision, the effects of age on surround suppression of motion shows markedly different characteristics between central and peripheral vision.

2015 Glenn A. Fry Award Lecture: Driving toward a New Vision: Understanding the Role of Vision in Driving.

More than 90% of the sensory information that we use for driving is estimated to be visual. However, there is ongoing debate regarding the extent to which different ocular conditions and types of visual impairment affect driving performance and which visual functions are most important for safe driving. My program of research has sought to address these questions using a range of experimental approaches including measures of real-world driving performance on a closed-circuit driving course and under in-traffic conditions. This article provides a current overview of how visual impairment affects driving ability and safety and also highlights the visual challenges of nighttime driving, including the visibility of vulnerable road users, based on the wider research literature, as well as providing a snapshot of some of my own studies. Emphasis is placed on those studies that are relevant to assessing a patient's visual fitness to drive, as well as providing appropriate advice regarding the impact of common visual impairments on driving ability and safety.

Eye Movements of Drivers with Glaucoma on a Visual Recognition Slide Test.

SIGNIFICANCE: Glaucoma has been shown to impair hazard detection ability and increase crash risk compared to controls. Differences in visual search behavior of the driving scene may explain these differences; however, there has been limited investigation of this issue with inconsistent findings. PURPOSE: Through eye movement tracking of older drivers with glaucoma, we explored their visual search behavior in comparison with controls while performing the DriveSafe, a slide recognition test purported to predict fitness to drive. METHODS: Thirty-one drivers with glaucoma (mean age, 71.7 ± 6.3 years; average better-eye mean defect,-3 dB; average worse-eye mean defect,-12 dB) and 25 age-matched controls underwent measurements of their visual acuity, contrast sensitivity, visual fields, and useful field of view (visual processing speeds). Participants' eye movements were recorded while they completed the DriveSafe test, which consists of brief presentations of static, real-world driving scenes containing various road users (pedestrians, bicycles, vehicles). Participants reported the types, positions, and direction of travel of road users in each image; the score was the total number of correctly reported items (maximum, 128). RESULTS: Drivers with glaucoma had significantly worse DriveSafe scores (P = .03), fixated on road users for shorter durations (P < .001), and exhibited smaller saccades (P = .02) compared with controls. For all participants, longer fixation times on road users (P < .001) was the eye movement measure most strongly associated with better DriveSafe scores; this relationship was not significantly different between groups. Useful field-of-view divided attention was the strongest visual predictor of DriveSafe scores. CONCLUSIONS: Eye movement changes in the glaucoma group may reflect increased difficulty in identifying relevant objects in the visual scene, which may be related to their lower DriveSafe scores. Given the DriveSafe's potential utility in assessing drivers with visual impairment before on-road testing, further investigations on how DriveSafe performance and eye movement patterns compare to those during on-road driving are warranted.

Validity of the +1.50 plus lens screening test as a predictor of uncorrected moderate hyperopia.

PURPOSE: Screening for uncorrected hyperopia in school children is important given its association with poorer visual function and academic performance. However, standard distance visual acuity screening may not detect low to moderate hyperopia. The plus lens test is used to screen for hyperopia in many school screening protocols, but has not been well validated. The current study investigated the effectiveness of the plus lens test to identify hyperopia in school children. METHODS: Participants included Grade 2 school children. Monocular distance visual acuity (logMAR letter chart) was measured unaided, and then through a +1.50D lens, known as the plus lens test. Cycloplegic refraction was undertaken to classify moderate hyperopia (≥+2.00D). Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were calculated for commonly used cut-offs for the plus lens test: 6/6, 6/9 and less than two lines difference between unaided acuity and acuity through the plus lens test. RESULTS: The sample included 59 children (mean age 7.2 ± 0.4 years). Fourteen (24%) children were classified as having uncorrected hyperopia. The sensitivity and specificity of the +1.50 plus lens test for identifying hyperopia were 0% and 98% respectively for a 6/6 cut-off, 29% and 91% for 6/9 cut-off, and 50% and 76% for a <2 line reduction between unaided acuity and acuity through the plus lens test. Receiver Operating Curve (ROC) analysis revealed area under curves of 0.69 based on acuity through the plus lens test, and 0.65 for a reduction in acuity through the plus lens test. CONCLUSIONS: The plus lens test has low sensitivity for detecting uncorrected hyperopia using traditional cut-offs of 6/9 or better. This raises questions about the role of the plus lens test in school screening batteries.