30 resultados para Eye disease
Resumo:
Objective: To understand the knowledge and attitudes of rural Chinese physicians, patients, and village health workers (VHWs) toward diabetic eye disease and glaucoma. Methods: Focus groups for each of the 3 stakeholders were conducted in 3 counties (9 groups). The focus groups were recorded, transcribed, and coded using specialized software. Responses to questions about barriers to compliance and interventions to remove these barriers were also ranked and scored. Results: Among 22 physicians, 23 patients, and 25 VHWs, knowledge about diabetic eye disease was generally good, but physicians and patients understood glaucoma only as an acutely symptomatic disease of relatively low prevalence. Physicians did not favor routine pupillary dilation to detect asymptomatic disease, expressing concerns about workflow and danger and inconvenience to patients. Providers believed that cost was the main barrier to patient compliance, whereas patients ranked poorly trained physicians as more important. All 3 stakeholder groups ranked financial interventions to improve compliance (eg, direct payment, lotteries, and contracts) low and preferred patient education and telephone contact by nurses. All the groups somewhat doubted the ability of VHWs to screen for eye disease accurately, but patients were generally willing to pay for VHW screening. The VHWs were uncertain about the value of eye care training but might accept it if accompanied by equipment. They did not rank payment for screening services as important. Conclusions: Misconceptions about glaucoma's asymptomatic nature and an unwillingness to routinely examine asymptomatic patients must be addressed in training programs. Home contact by nurses and patient education may be the most appropriate interventions to improve compliance.
Resumo:
Despite great progress in elucidating risk factors and effective treatments for eye disease in the last decades, blindness prevalence in the developing and developed world is either static or rising. A research agenda is needed to develop and test specific strategies to reduce the burden of blindness from glaucoma and other common eye diseases. Current knowledge about open and closed-angle glaucoma is reviewed and a strategy to reduce glaucoma blindness in Asia is suggested. A critical component of this strategy is enhanced training in the detection of narrow angles and optic nerve damage by direct examination. Specific research topics that could inform such a strategy are outlined.
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P>The current paper provides an overview of current knowledge on the structure and function of the eye. It describes in depth the different parts of the eye that are involved in the ocular manifestations seen in the mucopolysaccharidoses (MPS). The MPS are a group of rare inheritable lysosomal storage disorders characterized by the accumulation of glycosaminoglycans (GAGs) in cells and tissues all over the body, leading to widespread tissue and organ dysfunction. GAGs also tend to accumulate in several tissues of the eye, leading to various ocular manifestations affecting both the anterior (cornea, conjunctiva) and the posterior parts (retina, sclera, optic nerve) of the eye.
Resumo:
Introduction
Standard treatment for neovascular age-related macular degeneration (nAMD) is intravitreal injections of anti-VEGF drugs. Following multiple injections, nAMD lesions often become quiescent but there is a high risk of reactivation, and regular review by hospital ophthalmologists is the norm. The present trial examines the feasibility of community optometrists making lesion reactivation decisions.
Methods
The Effectiveness of Community vs Hospital Eye Service (ECHoES) trial is a virtual trial; lesion reactivation decisions were made about vignettes that comprised clinical data, colour fundus photographs, and optical coherence tomograms displayed on a web-based platform. Participants were either hospital ophthalmologists or community optometrists. All participants were provided with webinar training on the disease, its management, and assessment of the retinal imaging outputs. In a balanced design, 96 participants each assessed 42 vignettes; a total of 288 vignettes were assessed seven times by each professional group.The primary outcome is a participant's judgement of lesion reactivation compared with a reference standard. Secondary outcomes are the frequency of sight threatening errors; judgements about specific lesion components; participant-rated confidence in their decisions about the primary outcome; cost effectiveness of follow-up by optometrists rather than ophthalmologists.
Discussion
This trial addresses an important question for the NHS, namely whether, with appropriate training, community optometrists can make retreatment decisions for patients with nAMD to the same standard as hospital ophthalmologists. The trial employed a novel approach as participation was entirely through a web-based application; the trial required very few resources compared with those that would have been needed for a conventional randomised controlled clinical trial.
Resumo:
OBJECTIVES: To compare the ability of ophthalmologists versus optometrists to correctly classify retinal lesions due to neovascular age-related macular degeneration (nAMD).
DESIGN: Randomised balanced incomplete block trial. Optometrists in the community and ophthalmologists in the Hospital Eye Service classified lesions from vignettes comprising clinical information, colour fundus photographs and optical coherence tomographic images. Participants' classifications were validated against experts' classifications (reference standard).
SETTING: Internet-based application.
PARTICIPANTS: Ophthalmologists with experience in the age-related macular degeneration service; fully qualified optometrists not participating in nAMD shared care.
INTERVENTIONS: The trial emulated a conventional trial comparing optometrists' and ophthalmologists' decision-making, but vignettes, not patients, were assessed. Therefore, there were no interventions and the trial was virtual. Participants received training before assessing vignettes.
MAIN OUTCOME MEASURES: Primary outcome-correct classification of the activity status of a lesion based on a vignette, compared with a reference standard. Secondary outcomes-potentially sight-threatening errors, judgements about specific lesion components and participants' confidence in their decisions.
RESULTS: In total, 155 participants registered for the trial; 96 (48 in each group) completed all assessments and formed the analysis population. Optometrists and ophthalmologists achieved 1702/2016 (84.4%) and 1722/2016 (85.4%) correct classifications, respectively (OR 0.91, 95% CI 0.66 to 1.25; p=0.543). Optometrists' decision-making was non-inferior to ophthalmologists' with respect to the prespecified limit of 10% absolute difference (0.298 on the odds scale). Optometrists and ophthalmologists made similar numbers of sight-threatening errors (57/994 (5.7%) vs 62/994 (6.2%), OR 0.93, 95% CI 0.55 to 1.57; p=0.789). Ophthalmologists assessed lesion components as present less often than optometrists and were more confident about their classifications than optometrists.
CONCLUSIONS: Optometrists' ability to make nAMD retreatment decisions from vignettes is not inferior to ophthalmologists' ability. Shared care with optometrists monitoring quiescent nAMD lesions has the potential to reduce workload in hospitals.
TRIAL REGISTRATION NUMBER: ISRCTN07479761; pre-results registration.
Resumo:
Aqueous humor is actively produced in the ciliary epithelium of the anterior chamber and has important functions for the eye. Under normal physiological conditions, the inflow and outflow of the aqueous humor are tightly regulated, but in the pathologic state this balance is lost. Aqueous outflow involves structures of the anterior chamber and experiences most resistance at the level of the trabecular meshwork (TM) that acts as a filter. The modulation of the TM structure regulates the filter and its mechanism remains poorly understood. Proteomic analyses have identified cochlin, a protein of poorly understood function, in the glaucomatous TM but not in healthy control TM from human cadaver eyes. The presence of cochlin has subsequently been confirmed by Western and immunohistochemical analyses. Functionally, cochlin undergoes multimerization induced by shear stress and other changes in the microenvironment. Cochlin along with mucopolysaccharide deposits have been found in the TM of glaucoma patients and in the inner ear of subjects affected by the hearing disorder DNFA9, a late onset, progressive disease that also involves alterations in fluid shear regimes. In vitro, cochlin induces aggregation of primary TM cells suggesting a role in cell adhesion, possibly in mechanosensation, and in modulation of the TM filter.
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Purpose: To investigate the association of cardiovascular risk factors and inflammatory markers with neovascular age-related macular degeneration (AMD). Design: Cross-sectional case-control study. Participants: Of the 410 of the =65-year-old community sample invited to attend, 205 participated (50% response rate). Of the 215 clinic attendees who were invited to participate, 212 agreed to take part (98% response rate). A diagnosis of neovascular AMD in at least one eye was made in 193 clinic attendees and 2 of the community sample. Methods: Clinic and community participants underwent a detailed ophthalmic examination with fundus imaging, were interviewed for assessment of putative risk factors, and provided a blood sample. Analysis included levels of serum lipids, intercellular adhesion molecule 1 (ICAM), vascular cellular adhesion molecule (VCAM), and C-reactive protein (CRP). All participants were classified by fundus image grading on the basis of the eye with more severe AMD features. Main Outcome Measure: Neovascular AMD. Results: There were 195 participants with choroidal neovascularization in at least one eye, 97 nonneovascular AMD participants, and 115 controls (no drusen or pigmentary irregularities in either eye). In confounder-adjusted logistic regression, a history of cardiovascular disease was strongly associated with neovascular AMD (odds ratio [OR], 7.53; 95% confidence interval [CI], 2.78-20.41). Cigarette smoking (OR, 3.71; 95% CI, 1.25-11.06), being in the highest quartile of body mass index (OR, 3.82; 95% CI, 1.22-12.01), stage 2 hypertension (OR, 3.21; 95% CI, 1.14-8.98), and being in the highest quartile of serum cholesterol (OR, 4.66; 95% CI, 1.35-16.13) were positively associated with neovascular AMD. There was no association between AMD status and serum CRP, ICAM, or VCAM. Conclusions: Our results suggest that cardiovascular disease plays an etiological role in the development of choroidal neovascularization in a proportion of older adults and highlight the importance of control of blood pressure and cholesterol, avoidance of smoking, and maintenance of a normal body weight. © 2008 American Academy of Ophthalmology.
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The retina is exposed to a lifetime of potentially damaging environmental and physiological factors that make the component cells exquisitely sensitive to age-related processes. Retinal ageing is complex and a raft of abnormalities can accumulate in all layers of the retina. Some of this pathology serves as a sinister preamble to serious conditions such as age-related macular degeneration (AMD) which remains the leading cause of irreversible blindness in the Western world.
The formation of advanced glycation end products (AGEs) is a natural function of ageing but accumulation of these adducts also represents a key pathophysiological event in a range of important human diseases. AGEs act as mediators of neurodegeneration, induce irreversible changes in the extracellular matrix, vascular dysfunction and pro-inflammatory signalling. Since many cells and tissues of the eye are profoundly influenced by such processes, it is fitting that advanced glycation is now receiving considerable attention as a possible pathogenic factor in visual disorders.
This review presents the current evidence for a pathogenic role for AGEs and activation of the receptor for AGEs (RAGE) in initiation and progression of retinal disease. It draws upon the clinical and experimental literature and highlights the opportunities for further research that would definitively establish these adducts as important instigators of retinal disease. The therapeutic potential for novel agents that can ameliorate AGE formation of attenuate RAGE signalling in the retina is also discussed.
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The formation of advanced glycation end products (AGEs) is a key pathophysiological event with links to a range of important human diseases. It is now clear that AGEs may act as mediators, not only of diabetic complications(1 2) but also of widespread age related pathology such as Alzheimer's disease,(3) decreased skin elasticity,(4) (5) male erectile dysfunction,(6) (7) pulmonary fibrosis,(8) and atherosclerosis.(9 10) Since many cells and tissues of the eye are profoundly influenced by both diabetes and ageing, it is fitting that advanced glycation is now receiving considerable attention as a possible modulator in important visual disorders. An increasing number of reports confirm widespread AGE accumulation at sites of known ocular pathology and demonstrate how these products mediate crosslinking of long lived molecules in the eye. Such studies also underscore the putative pathophysiological role of advanced glycation in ocular cell dysfunction in vitro and in vivo.
Resumo:
Lipoxidation reactions and the subsequent accumulation of advanced lipoxidation end products (ALEs) have been implicated in the pathogenesis of many of the leading causes of visual impairment. Here, we begin by outlining some of the major lipid aldehydes produced through lipoxidation reactions, the ALEs formed upon their reaction with proteins, and the endogenous aldehyde metabolizing enzymes involved in protecting cells against lipoxidation mediated damage. Discussions are subsequently focused on the clinical and experimental evidence supporting the contribution of lipid aldehydes and ALEs in the development of ocular diseases. From these discussions, it is clear that inhibition of lipoxidation reactions and ALE formation could represent a new therapeutic avenue for the treatment of a broad range of ocular disorders. Current and emerging pharmacological strategies to prevent or neutralize the effects of lipid aldehydes and ALEs are therefore considered, with particular emphasis on the potential of these drugs for treatment of diseases of the eye.
Resumo:
Purpose: To describe associations between reticular pseudodrusen, individual characteristics, and retinal function.
Design: Cohort study.
Participants: We recruited 105 patients (age range, 52–93 years) who had advanced neovascular age-related macular degeneration (AMD) in only 1 eye from 3 clinical centers in Europe.
Methods: Minimum follow-up was 12 months. The eye selected for study was the fellow eye without advanced disease. Clinical measures of vision were distance visual acuity, near visual acuity, and results of the Smith-Kettlewell low-luminance acuity test (SKILL). Fundus imaging included color photography, red-free imaging, blue autofluorescence imaging, fluorescein angiography, indocyanine green angiography, and optical coherence tomography using standardized protocols. These were used to detect progression to neovascular AMD in the study eye during follow-up. All imaging outputs were graded for the presence or absence of reticular pseudodrusen (RPD) using a multimodal approach. Choroidal thickness was measured at the foveal center and at 2 other equidistant locations from the fovea (1500 μm) nasally and temporally. Metrics on retinal thickness and volume were obtained from the manufacturer-supplied automated segmentation readouts.
Main Outcome Measures: Presence of RPD, distance visual acuity, near visual acuity, SKILL score, choroidal thickness, retinal thickness, and retinal volume.
Results: Reticular pseudodrusen was found in 43 participants (41%) on 1 or more imaging method. The SKILL score was significantly worse in those with reticular drusen (mean score ± standard deviation [SD, 38±12) versus those without (mean score ± SD, 33±9) (P = 0.034). Parafoveal retinal thickness, parafoveal retinal volume, and all of the choroidal thickness parameters measured were significantly lower in those with reticular drusen than in those without. The presence of RPD was associated with development of neovascular AMD when corrected for age and sex (odds ratio, 5.5; 95% confidence interval, 1.1–28.8; P = 0.042). All participants in whom geographic atrophy developed during follow-up had visible RPD at baseline.
Conclusions: Significant differences in retinal and choroidal anatomic features, visual function, and risk factor profile exist in unilateral neovascular AMD patients with RPD compared with those without; therefore, such patients should be monitored carefully because of the risk of developing bilateral disease.
Resumo:
Previous research has shown that Parkinson's disease (PD) patients can increase the speed of their movement when catching a moving ball compared to when reaching for a static ball (Majsak et al., 1998). A recent model proposed by Redgrave et al. (2010) explains this phenomenon with regard to the dichotomic organization of motor loops in the basal ganglia circuitry and the role of sensory micro-circuitries in the control of goal-directed actions. According to this model, external visual information that is relevant to the required movement can induce a switch from a habitual control of movement toward an externally-paced, goal-directed form of guidance, resulting in augmented motor performance (Bienkiewicz et al., 2013). In the current study, we investigated whether continuous acoustic information generated by an object in motion can enhance motor performance in an arm reaching task in a similar way to that observed in the studies of Majsak et al. (1998, 2008). In addition, we explored whether the kinematic aspects of the movement are regulated in accordance with time to arrival information generated by the ball's motion as it reaches the catching zone. A group of 7 idiopathic PD (6 male, 1 female) patients performed a ball-catching task where the acceleration (and hence ball velocity) was manipulated by adjusting the angle of the ramp. The type of sensory information (visual and/or auditory) specifying the ball's arrival at the catching zone was also manipulated. Our results showed that patients with PD demonstrate improved motor performance when reaching for a ball in motion, compared to when stationary. We observed how PD patients can adjust their movement kinematics in accordance with the speed of a moving target, even if vision of the target is occluded and patients have to rely solely on auditory information. We demonstrate that the availability of dynamic temporal information is crucial for eliciting motor improvements in PD. Furthermore, these effects appear independent from the sensory modality through-which the information is conveyed.
Resumo:
Background: Chronic kidney disease (CKD) and hypertension are global public health problems associated with considerable morbidity, premature mortality and attendant healthcare costs. Previous studies have highlighted that non-invasive examination of the retinal microcirculation can detect microvascular pathology that is associated with systemic disorders of the circulatory system such as hypertension. We examined the associations between retinal vessel caliber (RVC) and fractal dimension (DF), with both hypertension and CKD in elderly Irish nuns.
Methods: Data from 1233 participants in the cross-sectional observational Irish Nun Eye Study (INES) were assessed from digital photographs with a standardized protocol using computer-assisted software. Multivariate regression analyses were used to assess associations with hypertension and CKD, with adjustment for age, body mass index (BMI), refraction, fellow eye RVC, smoking, alcohol consumption, ischemic heart disease (IHD), cerebrovascular accident (CVA), diabetes and medication use.
Results: In total, 1122 (91%) participants (mean age: 76.3 [range: 56-100] years) had gradable retinal images of sufficient quality for blood vessel assessment. Hypertension was significantly associated with a narrower central retinal arteriolar equivalent (CRAE) in a fully adjusted analysis (P = 0.002; effect size= -2.16 μm; 95% confidence intervals [CI]: -3.51, -0.81 μm). No significant associations between other retinal vascular parameters and hypertension or between any retinal vascular parameters and CKD were found.
Conclusions: Individuals with hypertension have significantly narrower retinal arterioles which may afford an earlier opportunity for tailored prevention and treatment options to optimize the structure and function of the microvasculature, providing additional clinical utility. No significant associations between retinal vascular parameters and CKD were detected.