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PURPOSE: Clinical assessment of rod and cone photoreceptor sensitivity often involves the use of extended dark adaptation times to minimise cone involvement or the use of bright adapting backgrounds to saturate rods. In this study we examine a new rod/cone sensitivity test, which requires minimal dark adaptation. The aim was to establish whether rod/cone sensitivity losses could be measured reliably in patients with retinal diseases that selectively affect rods or cones when compared to age-matched subjects with normal vision.\ud \ud METHODS: Flicker modulation thresholds (FMTs) were measured psychophysically, using cone- and rod-enhanced stimuli located centrally, and in four quadrants, at 5° retinal eccentricity in 20 patients (age range: 10-41 years) with cone-dominated (Stargardt's disease or macular dystrophy; n = 13) and rod-dominated (retinitis pigmentosa; n = 7) disease. These data were compared against age-matched normals tested with identical stimuli.\ud \ud RESULTS: Across all retinal locations, cone FMTs in cone-dominated diseases (Median ± IQR: 32.32 ± 28.15% for central location) were greater than a majority (83%; 49/59) of corresponding rod FMTs (18.7 ± 3.29%; p = 0.05) and cone FMTs of controls (4.24 ± 2.00%). Similarly, rod FMTs in rod-dominant disease (14.99 ± 22.58%) were greater than a majority (88%; 29/39) of the corresponding cone FMTs (9.09 ± 10.33%) (p = 0.13) and rod FMT of controls (6.80 ± 2.60 %).\ud \ud CONCLUSIONS: Cone-specific deficits were larger than rod-specific deficits in cone-dominated diseases, and vice versa in rod-dominated disease. These results suggest that the new method of assessing photoreceptor sensitivity has potential application in detecting specific rod/cone losses without the need for dark adaptation.

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

PURPOSE This study examined the effectiveness of the LuxIQ, the Apple iPad and a smart bulb in assessing optimal colour and illumination to facilitate reading in younger, older and visually impaired adults. METHODS Participants read standardised texts at baseline (normal lighting/no device), then using the Apple iPad, LuxIQ and smart bulb, with their normal vision (20/20 condition) and using a simulated reduction in visual acuity/contrast sensitivity (20/80 condition). Visually impaired participants followed the same procedure used in the 20/80 condition. RESULTS There was a significant interaction between condition and device in younger, F(1.5, 43.51) = 30.41, p

BACKGROUND: Older adults with visual impairments experience a higher risk of falling, and are more vulnerable to adverse health consequences associated with falls than those with normal vision. This study characterizes longitudinal changes in objectively measured physical activity and fear of falling (FoF) occurring after various types of falls in visually impaired older adults. DESIGN: Prospective cohort study. SETTING: Hospital-based enrollment. PARTICIPANTS: People with glaucoma or suspected glaucoma. MEASUREMENTS: Falls were defined as unintentionally coming to rest on the ground or a lower level, and injurious falls were determined though follow-up calls. Study participants were categorized into three groups–fallers with injurious consequences, fallers without injurious consequences, and non-fallers based on fall status in the first year. Physical activity was assessed by waist-bound accelerometer. FoF was evaluated by questionnaire, with Rasch modeling generating FoF scores where higher scores reflected worse FoF. The three-year longitudinal changes of physical activity and FoF were modeled using mixed-effects models. RESULTS: In linear models fully adjusted for visual field damage and other covariates, physical activity among injurious fallers showed greater annual (per year) declines in daily steps (−425 steps/day, 95% confidence interval [CI]: −793, −57), daily active minutes (−13 minutes/day, 95% CI: −21, −6), and daily moderate and vigorous physical activity (MVPA) minutes (−3 MVPA minutes/day, 95% CI: −5, 0) over the three-year period as compared to non-fallers; however, physical activity did not significantly decline among non-injurious fallers. No longitudinal increases in FoF scores were observed in injurious or non-injurious fallers when compared to non-fallers. CONCLUSION: Among visually impaired older adults, injurious falls identified prospectively over 12 months contributed to a significant decline in physical activity over a three-year period, while minimal changes were observed in FoF.

Purpose This study aimed to develop and validate a new Chinese reading chart for children. The characteristics of reading profiles among Hong Kong children were also investigated. Methods A new reading chart was developed using the design principles of the MNREAD chart. Children (N = 169) aged seven to 11 years with normal vision and no developmental or reading difficulties were recruited from four local Hong Kong primary schools located in four different districts. Reading performance was measured using three versions of the new Chinese reading chart for children as well as six short passages. Repeated reading measures were conducted for 79 participants 4–8 weeks later. A linear mixed-model analysis was performed for the reading measures to identify the contribution of each source of variation (individual participant, among-charts within-session and between-sessions, and error) to the total variance. Results Three reading parameters were derived from the Chinese reading chart for children – maximum reading speed (MRS), critical print size (CPS) and reading acuity (RA). Results from the linear mixed-model and Bland and Altman analyses revealed that all three versions of the chart were reproducible, with little variability among-charts and between-sessions (p

Objectives Reading performance has been considered as an effective functional endpoint for low vision. Contrary to many extensive studies for reading performance in English, there are few systematic studies for Chinese reading. Methods In the present study, the reading performance of 30 normally sighted Chinese college students was systematically investigated. All participants passed the equivalent test of Cambridge ESOL PET in China. The reading speeds for Chinese and English text at a variety of text sizes were measured with rapid serial visual presentation (RSVP). The threshold acuities for Chinese characters and English letters were measured. Maximum reading speed, critical font size, and critical acuity reserve were derived according to the individual's reading speed curve. Results The maximum reading speed for Chinese characters was 259.5 ± 38.2 characters/min, which was significantly faster than that for English letters (135.7 ± 18.5 words/min, p = 2.8 × 10‐18). The critical font size for Chinese characters was larger than that for English letters (24.2 ± 2.8 arcmin vs. 20.7 ± 1.0 arcmin, p = 1.6 × 10‐7). Interestingly, the critical acuity reserve was similar for these two languages (3.4 ± 0.4 for Chinese and 3.4 ± 0.2 for English, p = 0.4). Conclusion The present study provides the first step for establishing visual functional endpoints for Chinese reading. Our findings pose rigorous constrains on present theories in language information processing and brain plasticity.

Patients treated for bilateral congenital cataract are later impaired on several hallmarks of adults' expertise with upright faces but report no problem with remembering faces. Here, we provide the first formal data on their face memory. We compared 12 adults with a history of visual deprivation from bilateral congenital cataracts to 24 age-matched controls with normal vision on their ability to recognize famous and recently learned faces, and on their subjective impression of their face memory. Bilateral congenital cataract patients demonstrated a prosopagnosic-like deficit, being slower and less accurate in recognizing both famous faces and recently learned faces, despite not differing on most questions about their impression of their face memory. Patients' results on three perceptual tasks (the composite face effect, the Benton test of recognizing faces through a change in point of view, and the Jane test of sensitivity to feature spacing) were also not correlated with their face memory deficits. These results suggest that early visual input is necessary not only for perceptual expertise in differentiating among unfamiliar upright faces, but also for normal accuracy in remembering the identity of individual faces. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 56: 96-108, 2014.

Background Children with multiple impairments have more complex developmental problems than children with a single impairment. Method We compared children, aged 4 to 11 years, with intellectual disability (ID) and visual impairment to children with single ID, single visual impairment and typical development on ‘Child Behavior Check List/4–18’ (CBCL/4–18), Parent Report. Results Children with ID and visual impairment had more emotional and behavioural problems than other groups of children: with single impairment and with typical development (F = 23.81; d.f.1/d.f.2 = 3/156; P

Background: To estimate the rate of uncorrected refractive error and the associations with gender, age, ethnicity and place of residence. Design: Population-based study. Participants: Secondary school students in the Central Division of Fiji. Methods: All 58 secondary schools in the Central Division of Fiji were invited to participate and one class per year level at each participating school was randomly selected for screening. Visual acuity was tested using a logMAR chart and pinhole. Outcomes of screening included normal vision, corrected refractive error, uncorrected refractive error (VA

Purpose: To determine whether the hill of vision for Short-Wavelength Automated Perimetry (SWAP) is shallower for women who consume phyto-oestrogen-rich foods than for women who do not. Methods: Visual field data were compared for two groups of healthy amenorrhoeic women 48–69 years-old with normal vision and not using hormone replacement: (1) 24 subjects who reported consuming soy and/or flax products and (2) 20 subjects who reported not consuming these products. Two types of 24-2 visual fields were measured: (1) Full Threshold SWAP and (2) a white-on-white (W/W) field obtained using a Swedish Interactive Threshold Algorithm (SITA Standard). Results: The reduction of SWAP sensitivity from the centre of the field (4 loci, mean eccentricity = 4.2°) to the periphery (20 loci, mean eccentricity = 21.9°) was less for soy/flax consumers than for nonconsumers, both with age-referencing (mean difference = 1.7 dB, p = 0.018) and without (p = 0.012). Corresponding distinctions existed for the SWAP – W/W difference, and there was minimal effect for W/W fields alone. The peripheral age-referenced SWAP sensitivities averaged 2.5 dB higher for consumers than nonconsumers (p = 0.022). Conclusion: The between-group distinctions are consistent with the possibility (derived from the women’s health literature) that phyto-oestrogens may counteract a decline of short-wavelength-sensitive cone-mediated response among postmenopausal women. These results suggest another potential application for SWAP outside its original intended purpose as a glaucoma test. Future studies should assess whether phyto-oestrogen consumption is most beneficial for women who are sufficiently young and/or not too far beyond menopause.

PURPOSE: The influence of background attenuation on the spatial frequency bandwidth requirements for image recognition was assessed in normal young and older groups and in a group with age-related macular degeneration (AMD). Bandwidth requirements were also assessed in the visual periphery of young normal observers. METHODS: In Experiment 1, each observer was presented with 20 series of images. Each series consisted of a sequence of progressively low-pass filtered images, presented in an order of increasing bandwidth, i.e., according to an ascending method of limits. For half of the series, the background of the base image was selectively darkened by 80% of its original luminance. Three measures were analyzed: (1) the critical bandwidth defined as the bandwidth in cycles/image (cpi) at which 50% of the images were recognized, (2) the minimal bandwidth, defined as the minimal bandwidth at which images were recognized and (3) the proportion of images recognized at full bandwidth. In Experiment 2, young normal observers were similarly tested in central vision and at 5.5° eccentricity (superior or inferior visual field). A third background attenuation condition was included, as well, in which the background was low-pass filtered. RESULTS: The critical bandwidth for image recognition was significantly reduced by darkening the image background for normal young and old and the AMD groups. This improvement was found to be contrast dependent for the darkened background. In addition, AMD observers tended to recognize more images at full bandwidth if the background was darkened. For normal young observers, making the background low-pass was ineffective in lowering the critical bandwidth in the fovea. Fewer images were recognized at full bandwidth at 5.5° eccentricity for a low-pass background and marginally fewer for a darkened background. CONCLUSIONS: Selective attenuation of the image background can lead to reductions in the bandwidth requirements for image recognition in AMD. However, performance of young normal observers for images presented in the periphery was unlike AMD performance under the conditions investigated. These results have interesting implications for the design of image enhancement algorithms to aid low vision observers.

Background Unilateral refractive amblyopia is a common cause of reduced visual acuity in childhood, but optimal treatment is not well defined. This review examined the treatment effect from spectacles and conventional occlusion. Objectives Evaluation of the evidence of the effectiveness of spectacles and or occlusion in the treatment of unilateral refractive amblyopia. Search strategy We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and LILACS. Relevant conference proceedings were manually searched. There were no date or language restrictions. The searches were last run on 7 July 2008. Selection criteria Randomised controlled trials of treatment for unilateral refractive amblyopia by spectacles, with or without occlusion were eligible. We included studies with participants of any age. Data collection and analysis Two authors independently assessed abstracts identified by the searches. We obtained full text copies and contacted study authors where necessary. Eight trials were eligible for inclusion. Data were extracted from seven. No meta-analysis was performed. Main results For all studies mean acuity (standard deviation (SD)) in the amblyopic eye post treatment is reported. Comparison: Spectacles only versus no treatment (Clarke 2003). Mean (SD) visual acuity: spectacles group 0.31 (0.17); no treatment group 0.42 (0.19). Mean difference (MD) between groups -0.11 (borderline statistical significance: 95% confidence interval (CI) -0.22 to 0.00). Comparison: Spectacles plus occlusion versus no treatment (Clarke 2003). Mean (SD) visual acuity: full treatment 0.22 (0.13); no treatment 0.42 (0.19). Mean difference between the groups -0.20 (statistically significant: 95% CI -0.30 to -0.10). Comparison: Spectacles plus occlusion versus spectacles only: Clarke 2003 MD -0.09 (borderline statistical significance 95% CI, -0.18 to 0.00); PEDIG 2005b; MD -0.15 (not statistically significant 95% CI -0.32 to 0.02); PEDIG 2006a; MD 0.01 (not statistically significant 95% CI -0.08 to 0.10). Comparison: Occlusion regimes. PEDIG 2003a: 2 hours versus 6 hours for moderate amblyopia: MD 0.01 (not statistically significant: 95% CI -0.06 to 0.08); PEDIG 2003b: 6 hours versus full-time for severe amblyopia: MD 0.03 (not statistically significant: 95% CI -0.08 to 0.14). Stewart 2007a: 6 hours versus full-time occlusion: MD -0.12 (not statistically significant: 95% CI -0.27 to 0.03) Authors' conclusions In some cases of unilateral refractive amblyopia it appears that there is a treatment benefit from refractive correction alone. Where amblyopia persists there is some evidence that adding occlusion further improves vision. It remains unclear which treatment regimes are optimal for individual patients. The nature of any dose/response effect from occlusion still needs to be clarified. Plain Language Summary Patching treatment for amblyopia (lazy eye) caused by needing spectacles Patching treatment for amblyopia (lazy eye) caused by unequal optical errors in either eye when the (usually) worst eye can fail to develop optimum vision. Amblyopia is a condition where the vision of one (or more rarely both) eyes is reduced because the part of the brain responsible for vision does not develop properly. Amblyopia happens because the brain receives a weaker image from the eye with the greater optical error and prefers the eye with a clearer image. Children who have amblyopia because of optical errors are often given a patch to cover the good eye in addition to their spectacle correction to improve their vision. This review found that for some children with this type of amblyopia a period of spectacles wear can restore normal vision. At present it is not possible to tell at the start of treatment which children will just need spectacles and which ones will need a patch as well. For those children who still have reduced vision even after they have been wearing their spectacles for a while there is evidence that patching therapy further improves their vision. The amount of patching that will be needed for an individual child can not yet be predicted. This is because the effects of factors such as age are not fully understood. These findings are based on the results of six high quality trials.

To describe the role of an ophthalmic optician in the eye protection activities of occupational health care this paper concerns the basic training of the opticians in Finland, the optoergonomics courses, the importance of eye protection activities, and the role of an optician in the protection of eyes and vision at work. It is concluded that it is important to correct the refraction of the employees, because the workers with poor vision have more industrial accidents than those with normal vision. A programme created to increase the use of eye protectors indicates the role of the optician in eye protection activities.

A series of 131 successive hospitalized cases of traumatic hyphaema after blunt injury of the eye were treated with complete bed-rest for 6 days and double eye-patching but without any topical medication. Seven patients (5.3%) had a secondary bleeding. The visual acuities of 115 patients were tested, and 105 regained their normal vision, i.e. 1.0 or over. These results are no better than those reported in series treated with moderate bed-rest for 3-4 days combined with topical administration of corticosteroids and mydriatics. The results indicate that our present treatment may be unnecessarily severe.

Delayed visual maturation (DVM) can present as an isolated anomaly (type 1A), but can be compounded by perinatal problems (type 1B), severe neurodevelopmental delay (type 2), or ocular anomalies/nystagmus (type 3), in which group the common feature appears to be nystagmus. The neurodevelopmental and ophthalmic aspects of 26 infants with DVM were studied. Onset of visual improvement, rate of acquisition of normal vision and eventual outcome were studied quantitatively, using an adaptation of the acuity card procedure. Neurodevelopmental assessment was performed after visual improvement. The results support the long-held clinical impression that if blindness is the presenting feature, neurodevelopmental outlook is excellent. DVM could represent a defect in the extrageniculostriate visual system, and the onset of vision in all types--and the development of nystagmus in type 3--could herald the emergence of geniculostriate function.

This report describes two families with the Nance-Horan syndrome, an X-linked trait featuring lenticular cataracts and anomalies of tooth shape and number. Previous reports have described blindness in affected males but posterior sutural cataracts with normal vision as the primary ocular expression in heterozygous females. In one of these two families, the affected female is not only blind in one eye but reportedly had supernumerary central incisors (mesiodens) removed. This constitutes the most severe ocular and dental expression of this gene in heterozygous females yet reported.

In normal vision, visual scenes are predictable, as they are both spatially and temporally redundant. Evidence suggests that the visual system may use the spatio-temporal regularities of the external world, available in the retinal signal, to extract information from the visual environment and better reconstruct current and future stimuli. We studied this by recording neuronal responses of primary visual cortex (area V1) in anaesthetized and paralysed macaques during the presentation of dynamic sequences of bars, in which spatio-temporal regularities and local information were independently manipulated. Most V1 neurons were significantly modulated by events prior to and distant from stimulation of their classical receptive fields (CRFs); many were more strongly tuned to prior and distant events than they were to CRFs bars; and several showed tuning to prior information without any CRF stimulation. Hence, V1 neurons do not simply analyse local contours, but impute local features to the visual world, on the basis of prior knowledge of a visual world in which useful information can be distributed widely in space and time.

Purpose: To evaluate a new letter matching visual acuity (VA) chart (the KM chart) for children aged 5-7 years, designed as a Monoyer-based chart, in order to obtain a better consistency between school and preschool VA recordings. Methods: Visual acuities were assessed using three methods: the HVOT, KM and Monoyer charts. Comparisons were made between the KM method versus the HVOT and Monoyer methods, respectively. Children with normal vision and with different degrees of amblyopia were investigated. Results: Visual acuity levels appeared significantly higher in children with amblyopia when tested with the HVOT chart than when tested with the KM chart. Visual acuities obtained with the Monoyer and KM methods were comparable. The difference between the Monoyer and KM methods on the one hand, and the HVOT method on the other, can be explained by the fact that the HVOT chart elicits less crowding effect than the other two charts. Conclusions: Visual acuity in children with amblyopia might be overestimated if the HVOT test alone is used to assess vision. Use of the HVOT chart, therefore, should be restricted to the 3.5-4.5 years age group, for whom the KM chart is somewhat too difficult. In our opinion the KM chart should be preferred for use with older preschool children because it shows good consistency with the Monoyer chart. (Less)

Following an application from Omikron Italia S.r.l. submitted for authorisation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Italy, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation of a health claim related to cytidine 5-diphosphocholine and maintenance of normal vision. The Panel considers that the food constituent cytidine 5-diphosphocholine (CDP-choline or citicoline), which is the subject of the health claim, is sufficiently characterised. The claimed effect, maintenance of normal vision, is a beneficial physiological effect. The Panel considers that no conclusions can be drawn from the three narrative reviews and the eight human intervention studies provided by the applicant for the scientific substantiation of the claim. The Panel concludes that a cause and effect relationship has not been established between the consumption of CDP-choline and maintenance of normal vision.

Normal vision depends on the normal function of retinal neurons, so vision loss in diabetes must ultimately be explained in terms of altered neuronal function. However to date relatively little attention has been paid to the impact of diabetes on the neural retina. Instead, the focus of most research has been primarily on retinal vascular changes, with the assumption that they cause altered neuronal function and consequently vision loss. An increasing body of evidence suggests that alterations in neuronal function and viability may contribute to the pathogenic mechanisms of diabetic retinopathy beginning shortly after the onset of diabetes. This view arises from neurophysiological, psychometric, histopathological and biochemical observations in humans and experimental animals. The collective evidence from past and recent studies supports the hypothesis that neurodegeneration, together with functional changes in the vasculature, is an important component of diabetic retinopathy. The authors invite other investigators to include the neural retina as a component of their studies so that the pathogenesis of diabetic retinopathy can be understood more clearly.

A 10-year-old spayed domestic shorthaired cat was presented for behavioural changes, signs suggestive of visual deficits and aimless circling. Neuro-ophthalmological examination suggested the cat had central blindness. CT scans following administration of iohexol demonstrated a contrast-enhancing mass in the vicinity of the third ventricle resulting in obstructive hydrocephalus. Following rostral tentorial craniotomy and incision through the cerebral cortex, the third ventricle was approached via the dilated left lateral ventricle. An ependymoma was seen through a dorsocaudolateral incision into the third ventricle, and removed by gentle manipulation and suction. The cat recovered unremarkably, regaining normal vision and behaviour.

The purpose of this study was to investigate performance on the Random-Dot E (RDE) stereotest under binocular and monocular non-stereoscopic viewing conditions. Sixteen adult observers with normal vision were tested with the RDE stereotest. Four new RDE tests were shown to each observer in varying combinations of monocular viewing, binocular but non-stereoscopic viewing, and normal binocular viewing conditions. The test conditions were masked (where possible) and were presented in pseudo-random order. Control experiments were also conducted using the Frisby stereotest. Fifteen of the sixteen observers could discern some differences between the plates monocularly and therefore satisfied the passing criterion of the RDE test. Under these conditions, no observers could discern the stereoscopic E figure nor did any observer report a sensation of depth. No observer satisfied the passing criterion of the Frisby test monocularly. We conclude that caution should be used when interpreting results from the RDE stereotest, since adult observers could discern some differences between the test plates monocularly.

Forty-nine volunteers (20 to 75 years old) with normal vision were tested on color judgment using the Lanthony New Color Test (NCT), under twofluorescent light sources-warm white and SP30. Mixed analyses of variancefor the effects of light source, age, and saturation revealed that age and saturation had an effect on color judgment whereas light type did not. As age increased, the number of errors in color judgment increased, and at lower saturation levels the oldest age group made significantly more errors in color judgment than the youngest age group. Implicationsfor interior designers, color and lighting consultants, and planners are discussed.

Purpose A close interaction between neurosensory retina and the retinal pigmentepithelium (RPE) is a prerequisite for normal vision. Glaucomatous damage is characterized by neuroretinal degeneration. As a result, an imbalanced interaction exists. However, there is only limited evidence regarding RPE involvement in glaucoma patients’ eyes. This study investigates the correlation between retinal nerve fiber layer (RNFL) thickness and RPE alterations as detected by widefield fundus autofluorescence (FAF). Methods Peripapillary RNFL thickness was quantified by optical coherence tomography (OCT). The six corresponding retinal areas were defined by a standardized grid and FAF intensity/irregularities were assessed and correlated to RNFL measurements. Results 84 glaucomatous eyes were investigated. A correlation between RNFL thickness and standardized FAF in the corresponding topographic retina segments was observed. Correlation coefficients ranged between -0.12 to 0.35 and were statistically significant in the temporal inferior central field (r=0.35, p=0.02) and the temporal inferior peripheral field (r=0.31, p=0.04). Conclusion This study provides early evidence that in glaucoma RNFL degeneration may be accompanied by corresponding RPE alterations

Orbital teratoma is a rare, rapidly growing tumour that usually presents with congenital proptosis. Visual outcome is usually poor. A case is described of orbital teratoma presenting in an 18-month-old child as an inferior orbital mass with normal vision and intermittent hypertropia. Computed tomography demonstrated a cystic mass containing a tooth adjacent to the inferior orbital fissure. Histology revealed tissues derived from all three germ cell layers. The tumour was removed with preservation of vision and resolution of the strabismus. Late presentation of an orbital teratoma with a good visual outcome is exceptional.

Purpose Diabetic retinopathy (DR) is among the most common causes of blindness in the developed world. Since many patients retain normal vision and may experience only minimal reduction despite the presence of a severe, sight-threatening disease, screening and early detection of DR is highly recommended. Our purpose was to develop an automated DR screening system to gain computational support for high throughput screening activities. Methods Detection of microaneurysms (MA) - the most important indicators and the earliest signs of DR - and of other lesions (exudates, vascular structures, etc.) have been assembled in an ensemble-learning based framework, which has been tested on 1200 images of the Messidor database. Results Images were classified as having DR or non by the MA detector only with 95% sensitivity, 51% specificity and 76% accuracy. By including other lesions, our system reached 89% sensitivity, 82% specificity and 85% accuracy. Conclusion Our system has sensitivity/specificity values for the MA step comparable to or better then other automated systems available, as tested in the Retinopathy Online Challenge, where it is currently ranked as first. MA detection remains a key component in automated DR screening, but detection of other DR lesions can lead to further improvement. This work was supported in part by NKTH, TECH08-2, Hungary DRSCREEN project and the NIHR BMRC in Ophthalmology (TP).

Purpose To test the hypothesis that patients with bilateral glaucoma exhibit different eye movements compared to normally-sighted subjects when viewing computer displayed photographs, or searching for features or items within them. Methods Thirteen glaucoma patients and 17 age-matched subjects with normal vision viewed 28 randomised digital photographs of various everyday scenes displayed on a computer screen for 3 seconds each. Subjects were instructed to view the images as they would when looking at a slideshow. The subjects then viewed another set of images, but were timed to find a feature or item in the scene. Eye movements were simultaneously recorded using an Eyetracking system. Results In the passive viewing experiment, there was a significant reduction in the average number of saccades for glaucoma patients compared to controls (p

Background: A corneal fungal ulcer, which appeared to be quite superficial clinically, was found by histologic examination to unexpectedly involve the full thickness of the cornea. Methods: A patient with an apparent superficial corneal fungal ulcer due to Phialophora species was resistant to topical and intravenous antifungal therapy. Results: Penetrating keratoplasty cured the condition with retention of normal vision with a follow-up of two years. Conclusions: If keratomycosis is unresponsive to topical and intravenous antifungal therapy, penetrating keratoplasty may be required to eliminate the infection. Resistance to medical therapy might suggest presence of fungus far deeper in the cornea than suspected clinically.

Even though prophylactic medical examination of children has been carried out in Denmark since 1947, measurement of visual acuity in young children was not performed systematically until the National Health Service issued instructions making sight testing a major part of the 4 year medical examination. If this has had an effect, it should now be possible to record a fall in the number of school children with amblyopia as a result of anomalies of refraction and strabismus. The present investigation comprises all the children, who attended int the 2nd to 5th classes during the school year 1983/84, in schools in the municipality of Odense. 8769 school medical files were examined and 1216 children selected for supplementary eye examination. The remainder had normal vision without glasses. 1034 of those examined had an anomaly of refraction or reduced vision from other causes. 97% of all the eyes had a visual acuity of 6/6. The frequency of children with unilateral vision ≤6/12, and who did not suffer from eye disease, comprised 1.07%. There were statistically significantly more boys (1.39%) than girls (0.73%) with amblyopia. Thus, there is a fall in the number of amblyopic children in relation to previous Danish investigations. Bilateral reduction in visual acuity ≤6/18 was found in 0.09%; this has not changed to any greater extent during the last decades. Myopia was found in 4.0% of the children between the ages of 7–11 years. compared to previous studies no change was observed in the younger ages and modest rise in the older age groups. The onset of myopia occurred earlier in girls (9–10 years) than in boys (11 years). This may, in part, explain why myopia was seen in 4.4% of the girls and only in 3.6% of the boys. Severe myopia (>/6.0 D) was found in 13 children (18 eyes) corresponding to a frequency of 0.15%.

Introduction: Optic nerve hypoplasia (ONH) is a congenital deficiency of retinal ganglion cells and their axons that form the optic nerve. This condition is associated with visual deficits ranging from no light perception in severe cases to vision within normal ranges in mild cases of ONH. In mild cases, deficits can be limited to sectoral anomalies in the visual field and normal vision with colour vision anomalies have been reported. We report here a case of mild ONH with visual symptoms relating to Pulfrich phenomenon (PP) occurring spontaneously. Methods: A 12 year girl presented with typical visual symptoms (bumping into objects when walking, poor object location at tennis) associated with the spontaneous PP. A simple pendulum revealed a perceived anticlockwise ellipse indicative of a left eye defect. This was neutralised by an 85% transmission filter placed before the right eye. The inter-ocular latency difference was calculated to be 0.88 (S.D., 0.55) ms. Results: Fundus biometry showed an asymmetry in optic nerve size, the left being smaller than the right. Visual fields, anomaloscope and other colour vision tests, and both flash and pattern-reversal stimuli Visually Evoked Potentials showed no difference in visual function between the right and left eyes. Conclusions: A case of very mild ONH gives inter-ocular normal vision and visual function and yet a subtle inter-ocular delay occurs resulting in visual symptoms associated with PP. These were completely removed with tinted spectacles.

Technology to improve the clarity of video for home theater viewers is available utilizing a low cost enhancement chip (DigiVision DV1000). The impact of such a device on the preference for enhanced video was tested for people with impaired vision and normally sighted viewers. Viewers with impaired vision preferred the enhancement effects more than normally sighted viewers. Preference for enhancement was correlated with loss in contrast sensitivity and visual acuity. Preference increased with increased enhancement settings (designed for those with normal vision) in the group with vision impairments. This suggests that higher enhancement levels may be of even greater benefit, and a similar product could be designed to meet the needs of the large, growing population of elderly television viewers with impaired vision.

Purpose: To determine the effect of disruption of the inputs from the somatosensory and vestibular systems, refractive blur and dual tasking on postural stability in healthy, elderly subjects. Methods: Fifteen healthy, elderly subjects (mean age 71 ± 5 years, binocular VA −0.07 ± 0.05 logMAR, Snellen 20/17) with no history of falls and normal vision were recruited. Postural stability during standing was assessed using an AMTI force plate, and was determined as the Root Mean Square (RMS) of the Centre of Pressure (COP) signal in the anterior–posterior (AP) and medial–lateral (ML) directions collected over 30 s periods. Data were collected under normal standing conditions and when the inputs from the somatosensory and vestibular systems were disrupted. Measurements were also repeated with the subject being given an additional physical task (holding a tray of cups) and/or mental task (counting backwards). For all measurement conditions, postural sway was measured under conditions of binocular refractive blur of 0,1, 2, 4 and 8 D and with eyes closed. The data were analysed using a population-averaged linear model. Results: All factors except the additional physical task significantly decreased postural stability (p

Two experiments are described in which visual information is derived from a single moving boundary in the retinal image, all other boundaries being stabilized so that they contribute no visual information. In this situation the subject perceives the same colours on the two sides of the boundary as would be perceived in normal vision when, owing to eye-movements, all boundaries in the retinal image are moving relative to the retina. Thus complete information leading to perception of hue and saturation as well as brightness, and not merely differences of hue etc. on the two sides, can be derived from a single boundary.

Visual evoked responses (VERs) to brief light flashes were recorded from occipital regions in a group of 30 "cortically blind" children aged 4 months to 15 years and were compared with those of 31 children of similar age range who had the same type of central nervous system diseases but without signs or symptoms of blindness. The VERs were analyzed for amplitude, number of peaks, and morphology, following a method used previously by other authors. All the responses had some degree of abnormality, but there were no significant differences between the two groups. The findings suggest that recording of VERs is not always an accurate method for diagnosis of cortical blindness in children since the presence of abnormal responses is not incompatible with normal vision. Only 1 patient with coritcal blindness showed no response.

health depends upon the interaction of two sets of factors, the environment in which we live and the response of the body to this environment. Disease results when we are exposed to an intensity of harmful stimuli, either external or internal, which we cannot adequately overcome : our ability to cope with such stimuli depends in part, probably in a large part, on our genetic make-up. Simmons et al. (1955), May (1958) and others have stressed the complexity of the environment to which we may be exposed : apart from variations in physical conditions, such as climate, temperature, humidity and cosmic radiations for which bodily adjustments must be made, numerous disease producing micro-organisms may be present. The harmful effects of these organisms may be altered by such varied factors as general climatic conditions, rainfall, animal carriers and the type of vegetation, or they may vary for no apparent reason, such as in the decline in severity of syphilis over the last four centuries, which is considered by some to indicate a change in the spirochete itself. Any consideration of environment must take into account the cultural and social conditions in which we exist. Such factors as type of dwelling, domestic animals, sleeping habits (e.g. if the whole family group sleeps close together the chances of spread of any communicable disease are enhanced) and sanitary habits must all have a profound influence on health. Man himself is constantly changing his environment in an effort to improve his own existence : sometimes he actually creates new hazards. For example, small prematurely born babies are kept in an incubator where humidity, temperature, composition of the air and so on can be controlled, in an attempt to simulate the environment in utero. Unfortunately, some of these premature offspring were exposed to a high concentration of oxygen which stimulated growth of blood vessels immediately behind the lens of the eye, finally resulting in a new disease, retrolental fibroplasia, interfering with normal vision. As a further example may be mentioned the harmful environment to which man could be exposed in space travel : he will eventually succeed in overcoming this to allow survival under what are considered to-day to be extreme conditions. With continuous exposure to a constantly changing environment our adjustments to it must be constantly changing also. If the change in the environment is too

Five children with cancer treated with high dose cyclophosphamide experienced blurring of vision. In three patients, the blurring lasted less than one hour and disappeared, abruptly, but in the other two, it was prolonged, lasting three and 14 days with gradual improvement. In all five complete restoration of normal vision occurred. We have not found other reports of this association in the literature.