| 1. |
- Baptista, Antonio M. G., et al.
(författare)
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Causes of Vision Impairment in Portugal : A hospital based study
- 2015
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 56:7
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Causes of vision impairment (VI) are influenced by factors such as race or socio-economic circumstances. Because of this collecting national information is important for planning reduction of vision loss. The aim of this study was to determine causes of vision impairment in a population visiting ophthalmology departments in public hospitals in Portugal.Methods This study was designed according with the guidelines of the Vancouver Economic Burden of Vision Loss Group (IOVS, 2010, V51/4/1801). Recommendations are to collect hospital data during 1 year to determine causes of VI. We selected four public hospitals that are expected to have over 120-140K appointments per year. Files are analysed weekly to detect patients with vision impairment. Inclusion criteria are: visual acuity with the current refractive correction equal or less than 0.5 (20/40) in the better-seeing eye and/or a visual field of less than 20 degrees. Patients were selected by trained hospital staff (medics and orthoptists) and inserted in a database. Diagnoses were classified according the ICD9. Data collected included fundamental demographic information, main diagnosis, secondary diagnosis and comorbidities.Results We have now 2462 patients selected that correspond to 4 to 33 weeks of data collection. The number of weeks is variable because we did not start all hospitals simultaneously. From the current number of cases detected, 58% are female, 1.9% are under 20, 8.2% are between 20 and 50 and 89.9% are 50 years or older. The leading causes of vision impairment among these patients are diabetic retinopathy (DR), cataract (C), glaucoma (GC) and age-related macular degeneration (AMD). Using the North American definition of VI the proportions are 26.8% for DR, 25.5% for C, 10.4% for GC and 8.2% for AMD. The remaining causes of VI have percentages below 5% and in total they correspond to approximately 29% of the cases detected.Conclusions Our results show that the most common causes of vision impairment are eye diseases related with systemic conditions and aging of the population. Vision impairment was relatively low under the age of 20 and the causes were mostly inherited diseases. Numbers reported now will be more accurate at the end of the study but they already highlight the importance of targeting conditions such as diabetes.
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| 2. |
- Baptista, António M. G., et al.
(författare)
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The macular photostress test in diabetes, glaucoma, and cataract
- 2013
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Ingår i: 8th Iberoamerican Optics Meeting and 11th Latin American Meeting on Optics, Lasers, and Applications. - : SPIE - International Society for Optical Engineering.
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Konferensbidrag (refereegranskat)abstract
- Purpose. The photostress recovery time test (PSRT) has been widely reported as a helpful screening clinical tool. However, the poor standardization of its measurement technique remains to be a limitation among clinicians. The purpose of this study is to apply a recommended clinical technique to measure the PSRT in some of the most commons eye diseases to ascertain whether these diseases affect the PSRT values. Methods. One hundred and one controls and 105 patients, with diagnosed diabetes (without visible signs of diabetic retinopathy), primary open angle glaucoma (POAG) or cataracts underwent photostress testing. The test was performed with a direct ophthalmoscope for illuminating the macula for 30 seconds. Participants belonged to three age classes: A, B and C; and were divided into four groups: control, diabetic, POAG and cataract. The age range for A, B and C classes were respectively 43-54, 55-64 and 65-74 years. The groups were also further compared within each age class. In addition, the influence of age on PSRT was evaluated using the control group. Results. Results demonstrate that PSRT changes with age (p<0.02). In class A, diabetic group had a faster PSRT than control group, (mean ± standard deviation) 20.22±7.51 and 26.14±8.34 seconds. The difference between these groups was statistical significant (t-test, p=0.012). Cataract and POAG groups did not affect the PSRT significantly. Conclusions. The technique used for the Photostress showed that diabetics, younger than 54 years, may have faster PSRT and that, aging delays PSRT
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| 3. |
- Cima, Joana, et al.
(författare)
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EQ-5D and Activity Inventory : Measures of Visual Health Outcome
- 2015
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Ingår i: European Journal of Public Health. - : Oxford University Press (OUP). - 1101-1262 .- 1464-360X. ; 25:Suppl 3
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study is to test if EQ-5D, a more generic instrument, and Activity Inventory, a more specific instrument to the visual condition, produce consistent results when considering the different levels of visual impairment. By assessing how these instruments reflect visual status in a sample of patients with visual impairment, we will help to understand how they can work in cultural context and population in which they were never tested before.Method is based on Multivariate Analysis of Variance, in which the levels of visual impairment (slightly, moderate, severe/blindness) are defined through the visual acuity values, and the utility values derived from EQ-5D and the Activity Inventory.Participants were recruited in 3 public hospitals as a part of an ongoing study of prevalence and costs of visual impairment in Portugal. Patients attending outpatient appointments in these hospitals with acuity in the better eye of 0,30logMAR or worse and/or visual field in the better eye <20 degrees were invited to take part in face-to-face interviews. Additional visual measures, as acuity was collected using standardize methods. Visual acuity was assessed using an internally illuminated ETDRS chart at 4 m with room lights extinguished.The results show that both instruments have a good explanatory power. However when considering different clinical conditions, the AI presents better results. The EQ-5D due its low sensitivity/adaptability does not capture differences in health status in patients with slightly and moderate visual impairment.Since EQ-5D is the instrument most used in the evaluation of public health programs performance, the results suggest that its use should be more cautious in a situation of different difficulty levels. The results indicate that in these cases the EQ-5D should be used with a complementary instrument more specific to the clinical condition.Key messagesThe results suggest that with different difficulty levels the EQ-5D should be used with a complementary instrument more specific to the clinical condition to be produced more reliable resultsThis study is supported by the Portuguese Foundation for Science and Technology (FCT) -POCTI & FSE GRANT: PTDC/DPT-EPI/0412/2012
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| 4. |
- Freitas, Cristina, et al.
(författare)
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Functional impairment with minimal macular damage in femtosecond laser plasma injury : case report : [ Comprometimento funcional com dano macular mínimo em lesão com plasma de laser de femtosegundo: relato de caso ]
- 2013
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Ingår i: Arquivos Brasileiros de Oftalmologia. - 0004-2749 .- 1678-2925. ; 76:5, s. 317-319
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Tidskriftsartikel (refereegranskat)abstract
- A 26 years old female patient was examined twenty-four hours after observing laser-induced plasma formation in a process of nanoparticle production complaining of bilateral central scotoma. The ophthalmologic evaluation included dilated fundus observation, fluorescein angiography, and optical coherence tomography (OCT). In the first assessment, visual acuity was 20/20 in the right eye and 20/25 in the left eye. Ophthalmologic evaluation revealed colour changes in the macular region of both eyes. Optical coherence tomography showed a central interruption of the photoreceptor layer in both eyes and fluorescein angiography was normal. In subsequent appointments acuity was always 20/20 in both eyes. Abnormal optical coherence tomography findings disappeared in less than 5 months, but subjective complaints of scotoma in the left eye remained. Extra care must be taken in this type of experiment by, for example, reducing the time that the retina is directly exposed to the plasma radiation.
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| 5. |
- Goncalves Fernandes Ferreira, Flavio Pedro, et al.
(författare)
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Artificial eye for calibration of an eye-tracker, eye tracking calibration system and method thereof
- 2021
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Patent (populärvet., debatt m.m.)abstract
- Abstract(EN) An artificial eye for eye tracking calibration of an eye-tracker, comprising: an eye model comprising a foveal region; an optical position sensor arranged at the foveal region for transducing the position of a foveal light spot into a sensor position signal; a two-axis rotational pivoting support upon which the eye model is mounted; a two-axis actuator for rotating the eye model in said pivoting support; a feed-back electronic circuit, connected between the sensor and actuator, arranged to cause rotation of the eye model by said actuator such that the sensor position signal matches a reference position signal. The reference position signal may be adjustable to cause an off-set between the pupillary-axis of the eye model and a visual-axis defined by the reference position signal, in particular the reference position signal being adjustable by configuration of the feed-back electronic circuit.(FR) L'invention concerne un oeil artificiel pour l'étalonnage de suivi de l'oeil d'un oculomètre, comprenant : un modèle d'oeil comprenant une région fovéale ; un capteur de position optique disposé au niveau de la région fovéale pour convertir la position d'un point lumineux fovéal en un signal de position de capteur ; un support pivotant rotatif à deux axes sur lequel est monté le modèle oculaire ; un actionneur à deux axes pour faire tourner le modèle d'oeil dans ledit support pivotant ; un circuit électronique de rétroaction, connecté entre le capteur et l'actionneur, agencé pour provoquer la rotation du modèle d'oeil par ledit actionneur de telle sorte que le signal de position de capteur corresponde à un signal de position de référence. Le signal de position de référence peut être réglé pour provoquer un décalage entre l'axe pupillaire du modèle d'oeil et un axe visuel défini par le signal de position de référence, en particulier le signal de position de référence étant réglable par la configuration du circuit électronique de rétroaction.
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| 6. |
- Hernández-Moreno, Laura, et al.
(författare)
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The Portuguese version of the activity inventory
- 2015
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 56:7
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To characterize interventions needed by the population with visual impairment or to assess interventions in vision rehabilitation validated and standardized instruments used in different cultural contexts are necessary. The aim of this work was to characterize the functional status of a sample of people with visual impairment with the Portuguese version of the activity inventory (AI)Methods: A group of participants in the study Prevalence and Costs of Visual Impairment in Portugal (PC-VIP) was recruit to face-to-face interviews and the activity inventory was administered. The AI examines 50 goals split between three objectives: social functioning, recreation and daily living. Goals rated ‘not important’ were skipped, but for all other goals the participant was asked to rate its difficulty on a five point scale ranging from ‘not difficult’ to ‘impossible without help’. The difficulty responses were Rasch analysed (Winsteps v3.81.0) to produce a continuous measure of visual ability (AI score). Additional information about distance and near visual acuity (ETDRS scale), contrast sensitivity (MARS test) and critical print size (MNREAD test) was collected.Results: A total of 94 persons participated in this study. Some participants were not able to read or recognize letters due to their poor vision or poor literacy and were excluded from further analysis. Data reported here are from 62 participants, median age 63y (range=12-85) and the most common cause of visual impairment were retinal diseases. Mean presenting acuity in the better eye was 0.93logMAR (SD=0.5). The mean difficulty (item measure) in the AI was -0.33 logits (SD=0.96). The most difficult items were "sew or do needlework", "read the newspaper", "drive" and the easiest items were "provide care for a pet", "eat your meals", "use the restroom in a public place". The mean ability score (person measures) was 1.11 logits (SD=2.04). The ability measures in the AI were correlated with distance visual acuity (r=-0.57, p<.001), near visual acuity (r=-0.66, p<0.001), contrast sensitivity (r=0.62, p<.001) and critical print size (r=-0.60, p<.001).Conclusions: Our results indicate that the AI scores in a sample of people Portuguese people with visual impairment were in line with what has been found in other cultural contexts. The visual ability measured by the AI was correlated with visual function assessed by different visual tests, which shows that this instrument can be used with confidence.
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| 7. |
- Macedo, António Filipe, 1976-, et al.
(författare)
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An exploratory study of temporal integration in the peripheral retina of myopes
- 2017
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Ingår i: Proceedings of SPIE 10453. - : SPIE - International Society for Optical Engineering. - 9781510613843 - 9781510613836
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Konferensbidrag (refereegranskat)abstract
- The visual system takes time to respond to visual stimuli, neurons need to accumulate information over a time span in order to fire. Visual information perceived by the peripheral retina might be impaired by imperfect peripheral optics leading to myopia development. This study explored the effect of eccentricity, moderate myopia and peripheral refraction in temporal visual integration. Myopes and emmetropes showed similar performance at detecting briefly flashed stimuli in different retinal locations. Our results show evidence that moderate myopes have normal visual integration when refractive errors are corrected with contact lens; however, the tendency to increased temporal integration thresholds observed in myopes deserves further investigation.
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| 8. |
- Macedo, António Filipe, et al.
(författare)
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Temporal Processing in the Peripheral Retina
- 2012
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 53:14
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: There is an increasing number of reports in the literature about the possible influence of the peripheral refraction in myopia development. The aim of this work was to determine whether the peripheral refractive differences lead to changes in visual performance. We used a forced choice procedure to assess the speed and accuracy (visual processing) of people with and without myopia at detecting the direction of a Gabor patch presented at different retinal locations. Methods: Visual processing was measured twice in random order at 6 retinal locations: 10, 20 and 30 degrees eccentricity at the temporal and at the nasal retina. We tested the dominant eye of 8 adults (aged 19 to 33 years) with moderate myopia (spherical equivalent ranging from -4.25 to -2.00 D) and 8 age-matched adults without myopia (spherical equivalent from -0.63 to 0.75 D). Participants’ task was to report via bottom press whether the Gabor patch, with suprathreshold contrast and spatial frequency, was tilted 30º to the right or to the left. The target was preceded by a 50 msec duration cue, exposed for variable periods of 10, 30, 60, 90 and 140 msec, selected in random order, and followed by a noise mask until response was given. For each block, processing time was determined using the method of constant stimuli based in 400 trials per retinal location (80 trials per exposure). Threshold was defined as the exposure time yielding 75% of correct responses; results were analysed using linear mixed models (SPSS, v18). Results: The mean processing time in the group with myopia was 73 msec and in the group without myopia was 66 msec; the difference between groups was not statistically significant (p = 0.087). There was a statistically significant difference between the nasal and temporal retina, mean difference was 13 msec (p = 0.002) with smaller processing time in the nasal retina. Conclusions: For the type of paradigm used in this study, there was no difference in processing time of the peripheral retina between people with and people without myopia. Despite extensive reports in the literature about different refraction patterns in this study we found evidences that this does not translate into functional changes.
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| 9. |
- Macedo, António Filipe, et al.
(författare)
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Visual and health outcomes, measured with the activity inventory and the EQ-5D, in visual impairment
- 2017
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Ingår i: Acta Ophthalmologica. - : Wiley-Blackwell. - 1755-375X .- 1755-3768. ; 95:8, s. e783-e791
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Tidskriftsartikel (refereegranskat)abstract
- PurposeGeneric instruments to assess health utilities can be used to express the burden of health problems in widely used indexes. That is in contrast with what can be obtained with condition-specific instruments, outcomes are very specific and difficult to compare across conditions. The purpose of this study was to assess health and visual outcomes and its determinants in patients with visual impairment (VI) using the EQ-5D-3L and the Activity Inventory (AI).MethodsParticipants were recruited in different hospitals during the PCVIP-study. A total of 134 patients with acuity 0.30 logMAR or less in the better eye were interviewed. The AI includes 46 goals split between three objectives: social functioning, recreation and daily living, and was used to measure visual ability. The EQ-5D consists of five questions covering one domain each and was used to provide a measure of health states. Responses to each domain were combined to produce a single individual index.ResultsThe AI and the EQ-5D-3L showed enough discriminatory power between VI levels (p < 0.001), and their results were strongly correlated r(134) = 0.825, (p < 0.001). Explanatory factors for visual ability were level of VI in better eye, age and gender, R2 = 0.43, (p < 0.001). Explanatory factors for the EQ-5D-3L were level of VI in the better eye, comorbidities and gender, R2 = 0.36, (p < 0.001).ConclusionOur results showed that the EQ-5D-3L is useful when characterizing the burden of VI and to compute, when necessary, quality-adjusted-life-years (QALY) changes due to VI. However, it is important to consider that the EQ-5D-3L uses a coarse response scale, assesses a limited spectrum of domains and is influenced by comorbidities. This might limit its responsiveness to small changes in visual ability.
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| 10. |
- Marques, Ana Patricia, et al.
(författare)
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Emergence of intravitreal injections in a National Health System : 2002-2012
- 2014
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Ingår i: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 55:13
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Intravitreal injections of antivascular endothelial growth factor (anti-VEGF) are an innovative procedure with well-proven benefits to preserve vision in certain eye conditions. The aim of this study was to examine the diffusion of this treatment in the Portuguese National Health System.Methods We used a database of all in-patient and day cases stays from all Portuguese public hospitals during period 2002-2012. We selected cases based on four procedures, ICD-9-CM codes: 1414, 1475, 1479, 149. Given that these procedures are not specific for intravitreal injections it is likely that our results captured cases that are not anti-VEGF injections. Because we were only interested in the diffusion of new anti-VEGF treatments we included years 2002-2005 as baseline because during that period drugs anti-VEGF were not licenced. We calculated absolute values, yearly rates of episodes and rates of patients treated per 100,000 habitants.Results Our final sample included 98,408 episodes, 52% performed in men. The total number of episodes increased from 1,815 in 2002 to 25,106 in 2012 (mean annual increase of 32%). These values corresponded to an increase in ratios per 100,000 from 17.4 to 238.77. The highest increase was observed between 2007 and 2009 with an increase of 337%. The number of treated patients was six times higher in 2012 with 11,937 treated compared with 1,561 in 2002 (mean annual increase of 24%). The highest increase was also observed between 2006 and 2009. In 2012, 86.2% of the procedures were performed as day cases, representing an increase of 78.3% as compared to 2002. The percentage of patients older than 60 years increased from 60% in 2002 to 80% in 2012. Five diagnoses (See Figure: wet AMD, diabetic macular oedema, oedema of the retina, retinal neovascularization and non-specific AMD) were associated with 73% of these procedures in 2012, in contrast with only 16% in 2002.Conclusions The number of procedures grew exponentially since anti-VGEF treatments were approved. The aging of the population and the expected growth in conditions such as diabetes and AMD are likely to increase the demand for these procedures in years to come. These factors are likely to impose tremendous challenges to health services. That will happen not only due to the price of the procedures but also for number of physicians and other staff needed in Ophthalmology departments. View
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