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• W2048160905 abstract "To determine the efficacy of prisms used for redirection of incoming images towards the peripheral retina in cases with macular function loss. Meta-analysis of published work reporting outcomes from interventions using prisms was performed. The primary outcome measure selected for analysis was visual acuity (VA) used for viewing distance targets. Pooled data from 449 cases where prisms were prescribed for wearing in distance glasses were analysed. Visual acuity was better after using prisms (1.05 versus 0.89 logMAR units, p < 0.044). Mean effect size for improving VA was 79 bigger than the effect size calculated for the control group (0.158 versus 0.002). Most patients (76%) reported compliance with the therapy and also reported other benefits directly derived from the realized VA improvement. Published studies collectively offer positive evidence in support of using prisms for low vision rehabilitation after macular function loss. Further research is required to reach definitive binding conclusions. The demographic profile of the Western World is changing. Evidence suggests that the population is ageing with an increase in incidence of conditions, which will result in visual impairments (Taylor 2003). It was estimated that there are approximately 124 million people worldwide who have low vision (LV) (Resnikoff et al. 2004) with a high probability that actual numbers are much higher. Statistics show that the leading cause of central vision loss among Canadians 50 years and older is age-related macular degeneration, which results in LV in nearly 1 million individuals (CNIB 2006). It is expected that in the United States, the annual number of new cases of visual impairment will double that of the current rate by 2025 (Massof 2002) and it will affect about 1.5 million people in France. Vision rehabilitation for such vast numbers of patients is an urgent and impending need as is its cost to the public purse. Of special interest are rehabilitation methods aiming at reducing the impact from loss of central vision. Current vision therapy protocols for central vision loss aim to enhance awareness to scotoma and peripheral preferred retinal loci (PRL) by teaching redirection of incoming images towards the peripheral retina. A large number of practitioners, mainly in the United States, practice PRL and scotoma awareness methods to implement this rehabilitation concept. This method is common in Western countries and well publicized in the low vision rehabilitation (LVR) literature (Stelmack et al. 2004). Prisms are also used as a device for LVR and occupy a special place in the imagination of practitioners as well as in patients. They derive their mythology from the ability they have to break the path of light and change its direction, a not so small feat, given the ubiquitous knowledge that light travels always in straight lines. In addition, prisms also offer an intriguing alternative to the traditional method of magnification used for eons in LVR practice. The discovery that prisms enhance vision in many who lost it enchanted generations of practitioners, and many use them today in clinical practice. Theoretically prisms may achieve the same as PRL and scotoma awareness methods. If used together with PRL and scotoma awareness methods, they even may enhance further LVR outcomes. Use of prisms would be logical, practical and would require only passive patient participation. Few studies were published on use of prisms for LVR after macular function loss, and there is no reliable single study offering compelling evidence one way or another. Furthermore, a recent study suggests that PRL and scotoma awareness training are inefficient (Seiple et al. 2011). Hence, there is a current and urgent need to revisit the issue and attempt to determine whether prisms are efficacious in vision rehabilitation. Meta-analysis of available data may provide such answer. This is the endeavour that we attempt with this article. A review of published work based on the usage of internet search engines was carried out. Publications were identified according to keywords pertinent to various aspects of use of prisms in LVR extracted from a review paper on LVR (Markowitz 2006a). Only work published in the English and French languages was included in the study. After the search, the articles were reviewed and tabulated in Table 1. All studies identified were included, regardless of methodology or sample sizes. Outcomes that could be related to changes in visual acuity (VA) were reported by all studies. The primary outcome measure selected for analysis was VA for viewing distance targets. The papers reviewed presented VA data in a variety of formats and units and therefore required ‘translation’ to one system of LogMar units. In one case (Rosenberg et al. 1989), there were no reported data on VA; however, other outcome measures were reported. Yet in another case, near VA data reported was converted to reflect distance VA values (Romayananda et al. 1982). Analysis was based on descriptive statistics (frequency distributions, mean, standard deviation and t-test). Effect size for distance VA was calculated also. Effect size was defined as the difference of means related to the pooled standard deviation (Cohen 1988). Analysis was performed to determine heterogeneity and sensitivity. Meta-analysis of pooled data from all studies was performed to satisfy the purpose of this study with the Comprehensive Meta Analysis software (cma, v 2; Biostat, Englewood, NJ, USA). Review of the literature identified only nine published studies (Romayananda et al. 1982; Rosenberg et al. 1989; Verezen et al. 1996, 2006; Bertrand et al. 1997; Parodi et al. 2004; Vettard et al. 2004; Smith et al. 2005; Al-Karmi & Markowitz 2006). One study (Verezen et al. 2006) included in fact two separate studies and as such each was reported and analysed separately (Verezen et al. 2006; Verezen et al. 2006). The methodology used by various authors was far from uniform, and all studies are flawed, some more, some less. Studies were mostly prospective with the exception of two retrospective studies (Al-Karmi & Markowitz 2006; Verezen et al. 2006). Only three studies used a design, which includes a control group in addition to the interventional group (Parodi et al. 2004; Smith et al. 2005; Al-Karmi & Markowitz 2006). We identified only two prospective randomized studies, while the rest were observational case series (Parodi et al. 2004; Smith et al. 2005). The Oxford Centre for Evidence-based Medicine (http://www.cebm.net/index.aspx?o=1025) guidelines provided the modality for classification of research studies strength. Accordingly, two studies (level 3b, individual case–control studies) qualified as fair evidence (B studies) in linking the use of the intervention (prisms) to the observed outcome (VA) (Rosenberg et al. 1989; Al-Karmi & Markowitz 2006). Evidence classified as weak (C studies) is provided by five studies (level 4, case series) and two studies qualified as strong evidence (A studies; level 1b, randomized control trials) (Parodi et al. 2004; Smith et al. 2005). Compliance as a factor in data analysis and conclusions is essential when scrutinizing interventions in clinical care. In one of the randomized studies, it is reported that about 70% of the participants used the prism glasses prescribed rarely or not at all (Smith et al. 2005). Randomized studies omitting compliance as a factor in data analysis are widely known to underestimate effects under scrutiny (Nagelkerke et al. 2000). Two additional studies offer no data on compliance (Romayananda et al. 1982; Vettard et al. 2004). A variety of outcome measures were reported. Some studies presented data on reading speed (Smith et al. 2005) and/or critical print size (Romayananda et al. 1982; Rosenberg et al. 1989; Bertrand et al. 1997; Vettard et al. 2004; Al-Karmi & Markowitz 2006). Other reported data on abilities involved in activities of daily living like walking (Rosenberg et al. 1989; Smith et al. 2005; Verezen et al. 2006), spatial orientation (Rosenberg et al. 1989; Verezen et al. 1996, 2006; Smith et al. 2005), face recognition (Verezen et al. 1996, 2006) or better contrast identification (Bertrand et al. 1997; Verezen et al. 2006). Most reported data on VA. Altogether, a total of 727 subjects were enrolled in the various studies (Table 1). Only 479 people participated in the intervention group, and 109 took part in control groups. In 479 cases, prisms were prescribed for wearing in distance glasses. Wearing time reported was between 3 and 54 months (mean 14.5), and the average amount of prisms used was 10.3/5.8 prism dioptres (mean/SD) with the base in various directions. With the exception of two studies (Smith et al. 2005; Verezen et al. 2006), compliance in wearing the glasses was high (75.8%/31.5, mean/SD). At the end of the trial period, VA was better after using prisms (1.05 versus 0.89 logmar units, p ≤ 0.044). Out of the total enrolment, 109 subjects were used as a control group. Visual acuity in this group was not significantly different at the end of trial as compared to initial values. The pooled effect size on distance VA observed in the interventional group was 0.158 (p < 0.031) (Fig 1). The pooled effect size on VA acuity observed in the control group was 0.002 (p < 0.97). Hence, the effect size from using prisms is 79 larger than in those where prisms were not used. Heterogeneity was high in the interventional group (p < 0.001) and absent in the control group (p < 0.911). Two of the studies (Verezen et al. 1996, 2006) were the major contributors to heterogeneity. These studies included 197 cases and were based on patients with profound loss of vision. The rest of the studies reflected more or less a similar clinical population. Sensitivity analysis was performed by removing one study each time from the analysis to see whether the pooled effect size and its 95% confidence intervals and p-value change or not. Indeed, when removing the heterogeneous studies (Verezen et al. 1996, 2006; Verezen et al. 2006) from the analysis, sensitivity analysis found that this did not impact on the final effect size estimate (Fig 2). Forest plot for intervention group. Sensitivity analysis for intervention group. Low vision rehabilitation is a relatively new subspecialty in ophthalmology (Markowitz 2006b). Hence, we were forced to use in this study all data available and even so, not much was available. Studies under scrutiny were also based on limited number of participants and reported a variety of outcome measures tested with various methods (Colenbrander 2010). In all studies reviewed the traditional method of analysis used focused on statistical significance testing. Significance testing is not well suited to get a broader view well above any individual study as it is highly dependent on sample size and all the biases involved in the definition and selection of samples. Hence, our approach in our current review was to use meta-analysis. Meta-analysis changes the focus to the direction and magnitude of the effects across studies. The effect size makes meta-analysis possible as it standardizes findings across studies such that they can be directly compared one to another. In the final count, it provide a more powerful and credible estimate of the ‘true’ effect size as opposed to the effect size derived from any single study (Egger & Smith 1997). The rationale for performing meta-analysis in the context of prisms for LVR is therefore compelling in view of currently limited availability of published studies and their heterogeneity. None of the studies in this review presents the compelling evidence to sway opinion its way. Most, however, present a positive and encouraging view on the practice of using prisms in cases with macular function loss. Meta-analysis of all data summarized in this article shows collectively a significant benefit from using prisms in LVR. Demonstration that use of prisms enhances VA is fundamental as VA is the basis for all other possible outcomes such as face recognition, reading, writing, orientation and mobility and other. These results are reinforced by the sensitivity analysis, which shows that removal of heterogeneous studies could not change the size of the pooled effect size. Additional support to the positive results from this study is rendered by the fact that papers included in this study describe attempts to identify the retinal area with residual useful vision and prescribe prisms for redirecting of income images accordingly. The main limitations of this meta-analysis reside in the limited number of studies available for analysis, their heterogeneity and their contribution based on relatively weak evidence. Due to the fact that VA was assessed in each setting with various methods, VA findings need to be reassessed under stricter testing guidelines in future studies. It seems, however, based on the results from this meta-analysis that prisms for image relocation towards the periphery of the retina after macular function loss offer an easy modality of LVR and a relatively effective and beneficial one as well. A main benefit of the prisms method seems to be also non-dependence on cognitive skills, whereas the gaze training methods cannot be used in those with immature or poor cognition. Yet another important benefit when using prisms is in preserving the ability to make eye contact with other persons and also reducing torticollis and aberrant body positions used for eccentric viewing. Compliance seems to be relatively high and side effects seem to be relatively benign in most cases. Prisms should therefore be considered in clinical practice in addition or together with the commonly used gaze training methods as well as with other training methods (Nguyen et al. 2011). Further research and technology developments in future may offer additional insight into this aspect of vision rehabilitation." @default.
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• W2048160905 title "The use of prisms for vision rehabilitation after macular function loss: an evidence-based review" @default.
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• W2048160905 cites W2004534323 @default.
• W2048160905 cites W2007626415 @default.
• W2048160905 cites W2012336712 @default.
• W2048160905 cites W2050720072 @default.
• W2048160905 cites W2070575165 @default.
• W2048160905 cites W2071839287 @default.
• W2048160905 cites W2076807560 @default.
• W2048160905 cites W2078676474 @default.
• W2048160905 cites W2079534743 @default.
• W2048160905 cites W2084254640 @default.
• W2048160905 cites W2097027506 @default.
• W2048160905 cites W2124393280 @default.
• W2048160905 cites W2128213420 @default.
• W2048160905 cites W2143532939 @default.
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