Laser in Glaucoma and Ocular Hypertension (LiGHT) trial. A multicentre, randomised controlled trial: design and methodology

PURPOSE

The Laser in Glaucoma and Ocular Hypertension (LiGHT) Trial aims to establish whether initial treatment with selective laser trabeculoplasty (SLT) is superior to initial treatment with topical medication for primary open-angle glaucoma (POAG) or ocular hypertension (OHT).

DESIGN

The LiGHT Trial is a prospective, unmasked, multicentre, pragmatic, randomised controlled trial. 718 previously untreated patients with POAG or OHT were recruited at six collaborating centres in the UK between 2012 and 2014. The trial comprises two treatment arms: initial SLT followed by conventional medical therapy as required, and medical therapy without laser therapy. Randomisation was provided online by a web-based randomisation service. Participants will be monitored for 3 years, according to routine clinical practice. The target intraocular pressure (IOP) was set at baseline according to an algorithm, based on disease severity and lifetime risk of loss of vision at recruitment, and subsequently adjusted on the basis of IOP control, optic disc and visual field. The primary outcome measure is health-related quality of life (HRQL) (EQ-5D five-level). Secondary outcomes are treatment pathway cost and cost-effectiveness, Glaucoma Utility Index, Glaucoma Symptom Scale, Glaucoma Quality of Life, objective measures of pathway effectiveness, visual function and safety profiles and concordance. A single main analysis will be performed at the end of the trial on an intention-to-treat basis.

CONCLUSIONS

The LiGHT Trial is a multicentre, pragmatic, randomised clinical trial that will provide valuable data on the relative HRQL, clinical effectiveness and cost-effectiveness of SLT and topical IOP-lowering medication.

TRIAL REGISTRATION NUMBER

ISRCTN32038223, Pre-results.

Evidence of advanced stage colorectal cancer with longer diagnostic intervals: a pooled analysis of seven primary care cohorts comprising 11 720 patients in five countries

BACKGROUND

The benefits from expedited diagnosis of symptomatic cancer are uncertain. We aimed to analyse the relationship between stage of colorectal cancer (CRC) and the primary and specialist care components of the diagnostic interval.

METHODS

We identified seven independent data sets from population-based studies in Scotland, England, Canada, Denmark and Spain during 1997-2010 with a total of 11 720 newly diagnosed CRC patients, who had initially presented with symptoms to a primary care physician. Data were extracted from patient records, registries, audits and questionnaires, respectively. Data sets were required to hold information on dates in the diagnostic interval (defined as the time from the first presentation of symptoms in primary care until the date of diagnosis), symptoms at first presentation in primary care, route of referral, gender, age and histologically confirmed stage. We carried out reanalysis of all individual data sets and, using the same method, analysed a pooled individual patient data set.

RESULTS

The association between intervals and stage was similar in the individual and combined data set. There was a statistically significant convex (∩-shaped) association between primary care interval and diagnosis of advanced (i.e., distant or regional) rather than localised CRC (P=0.004), with odds beginning to increase from the first day on and peaking at 90 days. For specialist care, we saw an opposite and statistically significant concave (∪-shaped) association, with a trough at 60 days, between the interval and diagnosis of advanced CRC (P<0.001).

CONCLUSIONS

This study provides evidence that longer diagnostic intervals are associated with more advanced CRC. Furthermore, the study cannot define a specific 'safe' waiting time as the length of the primary care interval appears to have negative impact from day one.

A Quantitative and Qualitative Exploration of Photoaversion in Achromatopsia

Purpose

Photoaversion (PA) is a disabling and ubiquitous feature of achromatopsia (ACHM). We aimed to help define the characteristics of this important symptom, and present the first published assessment of its impact on patients' lives, as well as quantitative and qualitative PA assessments.

Methods

Molecularly confirmed ACHM subjects were assessed for PA using four tasks: structured survey of patient experience, novel quantitative subjective measurement of PA, visual acuities in differing ambient lighting, and objective palpebral aperture-related PA testing.

Results

Photoaversion in ACHM was found to be the most significant symptom for a substantial proportion (38%) of patients. A novel subjective PA measurement technique was developed and demonstrated fidelity with more invasive paradigms without exposing often very photosensitive patients to brighter light intensities used elsewhere. An objective PA measurement was also refined for use in trials, indicating that higher light intensities than previously published are likely to be needed. Monocular testing, as required for trials, was also validated for the first time.

Conclusions

This study offers new insights into PA in ACHM. It provides the first structured evidence of the great significance of this symptom to patients, suggesting that PA should be considered as an additional outcome measure in therapeutic trials. It also offers new insights into the characteristics of PA in ACHM, and describes both subjective and objective measures of PA that could be employed in clinical trials.

Health State Utility Values for Age-Related Macular Degeneration: Review and Advice

Health state utility values are a major source of uncertainty in economic evaluations of interventions for age-related macular degeneration (AMD). This review identifies and critiques published utility values and methods for eliciting de novo utility values in AMD. We describe how utility values have been used in healthcare decision making and provide guidance on the choice of utility values for future economic evaluations for AMD. Literature was searched using PubMed, and health technology assessments (HTA) were searched using HTA agency websites to identify articles reporting utility values or approaches to derive utility values in AMD and articles applying utilities for use in healthcare decision making relating to treatments for AMD. A total of 70 studies qualified for data extraction, 22 of which were classified as containing utility values and/or elicitation methods, and 48 were classified as using utility values in decision making. A large number of studies have elicited utility values for AMD, although those applied to decision making have focused on a few of these. There is an appreciation of the challenges in the measurement and valuation of health states, with recent studies addressing challenges such as the insensitivity of generic health-related quality of life (HRQoL) questionnaires and utility in the worse-seeing eye. We would encourage careful consideration when choosing utility values in decision making and an explicit critique of their applicability to the decision problem.

Concerns, perceived need and competing priorities: a qualitative exploration of decision-making and non-participation in a population-based flexible sigmoidoscopy screening programme to prevent colorectal cancer

OBJECTIVE

Optimising uptake of colorectal cancer (CRC) screening is important to achieve projected health outcomes. Population-based screening by flexible sigmoidoscopy (FS) was introduced in England in 2013 (NHS Bowel scope screening). Little is known about reactions to the invitation to participate in FS screening, as offered within the context of the Bowel scope programme. We aimed to investigate responses to the screening invitation to inform understanding of decision-making, particularly in relation to non-participation in screening.

DESIGN

Qualitative analysis of semistructured in-depth interviews and written accounts.

PARTICIPANTS AND SETTING

People from 31 general practices in the North East and East of England invited to attend FS screening as part of NHS Bowel scope screening programme were sent invitations to take part in the study. We purposively sampled interviewees to ensure a range of accounts in terms of beliefs, screening attendance, sex and geographical location.

RESULTS

20 screeners and 25 non-screeners were interviewed. Written responses describing reasons for, and circumstances surrounding, non-participation from a further 28 non-screeners were included in the analysis. Thematic analysis identified a range of reactions to the screening invitation, decision-making processes and barriers to participation. These include a perceived or actual lack of need; inability to attend; anxiety and fear about bowel preparation, procedures or hospital; inability or reluctance to self-administer an enema; beliefs about low susceptibility to bowel cancer or treatment and understanding of harm and benefits. The strength, rather than presence, of concerns about the test and perceived need for reassurance were important in the decision to participate for screeners and non-screeners. Decision-making occurs within the context of previous experiences and day-to-day life.

CONCLUSIONS

Understanding the reasons for non-participation in FS screening can help inform strategies to improve uptake and may be transferable to other screening programmes.

Preclinical Disability

Accomplishing a compression of morbidity will require prevention of disability, a significant component of illness in older adults. To do this, better understanding is needed of the natural history of functional loss prior to disability. The authors hypothesize that there is an identifiable stage of preclinical disability that will predict future disability and identify a focus for prevention. It is proposed, based on observations in the Johns Hopkins Functional Status Laboratory, that preclinical disability is characterized by persons who perceive no difficulty with performance of a task and yet are found to have either (a) general diminution in activities requiring related abilities, or (b) changes in the performance of specific tasks. Both models are due to impairments. The authors suggest that nondisabled persons use compensatory strategies that minimize functional restrictions resulting from impairment; this may keep functional decline at a preclinical level. These hypotheses, if verified in prospective studies, may provide a basis for early detection of those at risk of disability and suggest effective preventive measures.

A new bromelain-based enzyme for the release of Dupuytren's contracture: Dupuytren's enzymatic bromelain-based release

Objectives

Injectable Bromelain Solution (IBS) is a modified investigational derivate of the medical grade bromelain-debriding pharmaceutical agent (NexoBrid) studied and approved for a rapid (four-hour single application), eschar-specific, deep burn debridement. We conducted an ex vivo study to determine the ability of IBS to dissolve-disrupt (enzymatic fasciotomy) Dupuytren’s cords.

Materials and Methods

Specially prepared medical grade IBS was injected into fresh Dupuytren’s cords excised from patients undergoing surgical fasciectomy. These cords were tested by tension-loading them to failure with the Zwick 1445 (Zwick GmbH & Co. KG, Ulm, Germany) tension testing system.

Results

We completed a pilot concept-validation study that proved the efficacy of IBS to induce enzymatic fasciotomy in ten cords compared with control in ten cords. We then completed a dosing study with an additional 71 cords injected with IBS in descending doses from 150 mg/cc to 0.8 mg/cc. The dosing study demonstrated that the minimal effective dose of 0.5 cc of 6.25 mg/cc to 5 mg/cc could achieve cord rupture in more than 80% of cases.

Conclusions

These preliminary results indicate that IBS may be effective in enzymatic fasciotomy in Dupuytren’s contracture.

Cite this article: Dr G. Rubin. A new bromelain-based enzyme for the release of Dupuytren’s contracture: Dupuytren’s enzymatic bromelain-based release. Bone Joint Res 2016;5:175–177. DOI: 10.1302/2046-3758.55.BJR-2016-0072.

A Developmental Deficit in Localizing Objects from Vision

We describe a college student, A H, with a developmental deficit in determining the location of objects from vision The deficit is selective in that (a) localization from auditory or tactile information is intact, (b) A H reports the identity of mislocalized objects accurately, (c) visual localization errors preserve certain parameters of the target location, and (d) visual localization is severely impaired under certain stimulus conditions, but nearly intact under other conditions These results bear on the representation and processing of location information in the visual system, and also have implications for understanding developmental dyslexia

Minimally invasive burn care: a review of seven clinical studies of rapid and selective debridement using a bromelain-based debriding enzyme (Nexobrid®)

Current surgical and non-surgical eschar removal-debridement techniques are invasive or ineffective. A bromelainbased rapid and selective enzymatic debriding agent was developed to overcome these disadvantages and compared with the standard of care (SOC). The safety and efficacy of a novel Debriding Gel Dressing (DGD) was determined in patients with deep partial and full thickness burns covering up to 67% total body surface area (TBSA). This review summarizes data from seven studies, four of which were randomized clinical trials that included a SOC or control vehicle. DGD eschar debridement efficacy was >90% in all studies, comparable to the SOC and significantly greater than the control vehicle. The total area excised was less in patients treated with DGD compared with the control vehicle (22.9% vs. 73.2%, P<0.001) or the surgical/non-surgical SOC (50.5%, P=0.006). The incidence of surgical debridement in patients treated with DGD was lower than the SOC (40/163 [24.5%] vs. 119/170 [70.0%], P0.001). Less autografting was used in all studies. Long-term scar quality and function were similar in DGD- and SOCtreated. DGD is a safe and effective method of burn debridement that offers an alternative to surgical and non-surgical SOC.

Randomised, single-masked non-inferiority trial of femtosecond laser-assisted versus manual phacoemulsification cataract surgery for adults with visually significant cataract: the FACT trial protocol

INTRODUCTION

Cataract is one of the leading causes of low vision in the westernised world, and cataract surgery is one of the most commonly performed operations. Laser platforms for cataract surgery are now available, the anticipated advantages of which are broad and may include better visual outcomes through greater precision and reproducibility, and improved safety. FACT is a randomised single masked non-inferiority trial to establish whether laser-assisted cataract surgery is as good as or better than standard manual phacoemulsification.

METHODS AND ANALYSIS

808 patients aged 18 years and over with visually significant cataract will be randomised to manual phacoemulsification cataract surgery (standard care) or laser-assisted cataract surgery (intervention arm). Outcomes will be measured at 3 and 12 months after surgery. The primary clinical outcome is uncorrected distance visual acuity (UDVA, logMAR) at 3 months in the study eye recorded by an observer masked to the trial group. Secondary outcomes include UDVA at 12 months, corrected distance visual acuity at 3 and 12 months, complications, endothelial cell loss, patient-reported outcome measures and a health economic analysis conforming to National Institute for Health and Care Excellence standards.

ETHICS AND DISSEMINATION

Research Ethics Committee Approval was obtained on 6 February 2015, ref: 14/LO/1937. Current protocol: v2.0 (08/04/2015). Study findings will be published in peer-reviewed journals.

ISRCTN

77602616.

Free myocutaneous flap transfer to treat congenital Volkmann's contracture of the forearm

The purpose of this study is to report our experience with free functional muscle transfer procedures for the late sequelae of the rare condition of congenital Volkmann's ischaemic contracture of the forearm. Four children, with an average age of 9.5 years (range 1.5-17), were treated and were followed for a mean of 6 years (range 1-14). Two patients had dorsal forearm contractures, and two had both flexor and extensor forearm contractures. We carried out free functional muscle transfers to replace the flexor or extensor muscles. The functional result was assessed according to the classification system of Hovius and Ultee. All patients had wrist contractures and skeletal involvement with limb length discrepancy that influenced the outcome. All five transferred muscles survived and improved the function of the hand in three of the four patients. LEVEL OF EVIDENCE 4.

Assistive technology for children and young people with low vision

BACKGROUND

Recent technological developments, such as the near universal spread of mobile phones and portable computers and improvements in the accessibility features of these devices, give children and young people with low vision greater independent access to information. Some electronic technologies, such as closed circuit TV, are well established low vision aids and newer versions, such as electronic readers or off-the shelf tablet computers, may offer similar functionalities with easier portability and at lower cost.

OBJECTIVES

To assess the effect of electronic assistive technologies on reading, educational outcomes and quality of life in children and young people with low vision.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to October 2014), EMBASE (January 1980 to October 2014), the Health Technology Assessment Programme (HTA) (www.hta.ac.uk/), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 30 October 2014.

SELECTION CRITERIA

We intended to include randomised controlled trials (RCTs) and quasi-RCTs in this review. We planned to include trials involving children between the ages of 5 and 16 years with low vision as defined by, or equivalent to, the WHO 1992 definition of low vision. We planned to include studies that explore the use of assistive technologies (ATs). These could include all types of closed circuit television/electronic vision enhancement systems (CCTV/EVES), computer technology including tablet computers and adaptive technologies such as screen readers, screen magnification and optical character recognition (OCR). We intended to compare the use of ATs with standard optical aids, which include distance refractive correction (with appropriate near addition for aphakic (no lens)/pseudophakic (with lens implant) patients) and monocular/binoculars for distance and brightfield magnifiers for near. We also planned to include studies that compare different types of ATs with each other, without or in addition to conventional optical aids, and those that compare ATs given with or without instructions for use.

DATA COLLECTION AND ANALYSIS

Independently, two review authors reviewed titles and abstracts for eligibility. They divided studies into categories to 'definitely include', 'definitely exclude' and 'possibly include', and the same two authors made final judgements about inclusion/exclusion by obtaining full-text copies of the studies in the 'possibly include' category.

MAIN RESULTS

We did not identify any randomised controlled trials in this subject area.

AUTHORS' CONCLUSIONS

High-quality evidence about the usefulness of electronic AT for children and young people with visual impairment is needed to inform the choice healthcare and education providers and family have to make when selecting a technology. Randomised controlled trials are needed to assess the impact of AT. Research protocols should carefully select outcomes relevant not only to the scientific community, but more importantly to families and teachers. Functional outcomes such as reading accuracy, comprehension and speed should be recorded, as well as the impact of AT on independent learning and quality of life.

Irritable bowel syndrome: an integrated explanatory model for clinical practice

BACKGROUND

Although irritable bowel syndrome (IBS) is a symptom-based diagnosis, clinicians' management of and communication about the disorder is often hampered by an unclear conceptual understanding of the nature of the problem. We aimed to elucidate an integrated explanatory model (EM) for IBS from the existing literature for pragmatic use in the clinical setting.

METHODS

Systematic and exploratory literature searches were performed in PubMed to identify publications on IBS and EMs.

KEY RESULTS

The searches did not identify a single, integrated EM for IBS. However, three main hypotheses were elucidated that could provide components with which to develop an IBS EM: (i) altered peripheral regulation of gut function (including sensory and secretory mechanisms); (ii) altered brain-gut signaling (including visceral hypersensitivity); and (iii) psychological distress. Genetic polymorphisms and epigenetic changes may, to some degree, underlie the etiology and pathophysiology of IBS and could increase the susceptibility to developing the disorder. The three model components also fit into one integrated explanation for abdominal symptoms and changes in stool habit. Additionally, IBS may share a common pathophysiological mechanism with other associated functional syndromes.

CONCLUSIONS & INFERENCES

It was possible to elucidate an integrated, three-component EM as a basis for clinicians to conceptualize the nature of IBS, with the potential to contribute to better diagnosis and management, and dialog with sufferers.

Long-term effect of gene therapy on Leber's congenital amaurosis

BACKGROUND

Mutations in RPE65 cause Leber's congenital amaurosis, a progressive retinal degenerative disease that severely impairs sight in children. Gene therapy can result in modest improvements in night vision, but knowledge of its efficacy in humans is limited.

METHODS

We performed a phase 1-2 open-label trial involving 12 participants to evaluate the safety and efficacy of gene therapy with a recombinant adeno-associated virus 2/2 (rAAV2/2) vector carrying the RPE65 complementary DNA, and measured visual function over the course of 3 years. Four participants were administered a lower dose of the vector, and 8 were administered a higher dose. In a parallel study in dogs, we investigated the relationship among vector dose, visual function, and electroretinography (ERG) findings.

RESULTS

Improvements in retinal sensitivity were evident, to varying extents, in six participants for up to 3 years, peaking at 6 to 12 months after treatment and then declining. No associated improvement in retinal function was detected by means of ERG. Three participants had intraocular inflammation, and two had clinically significant deterioration of visual acuity. The reduction in central retinal thickness varied among participants. In dogs, RPE65 gene therapy with the same vector at lower doses improved vision-guided behavior, but only higher doses resulted in improvements in retinal function that were detectable with the use of ERG.

CONCLUSIONS

Gene therapy with rAAV2/2 RPE65 vector improved retinal sensitivity, albeit modestly and temporarily. Comparison with the results obtained in the dog model indicates that there is a species difference in the amount of RPE65 required to drive the visual cycle and that the demand for RPE65 in affected persons was not met to the extent required for a durable, robust effect. (Funded by the National Institute for Health Research and others; ClinicalTrials.gov number, NCT00643747.).

The role of primary care in cancer diagnosis via emergency presentation: qualitative synthesis of significant event reports

BACKGROUND

Patients diagnosed with cancer in the context of an emergency presentation (EP) have poorer outcomes. It is often assumed that such patients present to the emergency department without consulting their general practitioner (GP). Little work has been done to identify primary care involvement before hospital attendance.

METHODS

Participating primary care practices completed a significant event audit (SEA) report for the last patient diagnosed with cancer as a result of an EP. Accounts were synthesised and a qualitative approach to analysis undertaken.

RESULTS

SEAs for 222 patients were analysed. A range of cancers were included, the most common being lung (32.4%) and upper gastrointestinal (19.8%). In most cases, patients had contact with their practice before diagnosis, primarily in the period immediately before admission. In only eight cases had there been no input from primary care. Accounts of protracted primary care contact generally demonstrated complexity, often related to comorbidity, patient-mediated factors or reassurance provided by negative investigations. Learning points identified by practices centred on the themes of presentation and diagnosis, consultation and safety-netting, communication and system issues, patient factors and referral guidelines.

CONCLUSIONS

There is extensive primary care input into patients whose diagnosis results from EP, and for the most part potential 'delay' in referral can be reasonably explained by the complexity of the presentation or by coexisting patient factors.

Symptoms and other factors associated with time to diagnosis and stage of lung cancer: a prospective cohort study

BACKGROUND

This prospective cohort study aimed to identify symptom and patient factors that influence time to lung cancer diagnosis and stage at diagnosis.

METHODS

Data relating to symptoms were collected from patients upon referral with symptoms suspicious of lung cancer in two English regions; we also examined primary care and hospital records for diagnostic routes and diagnoses. Descriptive and regression analyses were used to investigate associations between symptoms and patient factors with diagnostic intervals and stage.

RESULTS

Among 963 participants, 15.9% were diagnosed with primary lung cancer, 5.9% with other thoracic malignancies and 78.2% with non-malignant conditions. Only half the cohort had an isolated first symptom (475, 49.3%); synchronous first symptoms were common. Haemoptysis, reported by 21.6% of cases, was the only initial symptom associated with cancer. Diagnostic intervals were shorter for cancer than non-cancer diagnoses (91 vs 124 days, P=0.037) and for late-stage than early-stage cancer (106 vs 168 days, P=0.02). Chest/shoulder pain was the only first symptom with a shorter diagnostic interval for cancer compared with non-cancer diagnoses (P=0.003).

CONCLUSIONS

Haemoptysis is the strongest symptom predictor of lung cancer but occurs in only a fifth of patients. Programmes for expediting earlier diagnosis need to focus on multiple symptoms and their evolution.

Assessing the impact of an English national initiative for early cancer diagnosis in primary care

BACKGROUND

The Cancer Networks Supporting Primary Care programme was a National Health Service (NHS) initiative in England between 2011 and 2013 that aimed to better understand and improve referral practices for suspected cancer.

METHODS

A mixed methods evaluation using semi-structured interviews with purposefully sampled key stakeholders and an analysis of Cancer Waiting Times and Hospital Episode Statistics data for all 8179 practices in England were undertaken. We compared periods before (2009/10) and at the end (2012/13) of the initiative for practices taking up any one of four specified quality improvement initiatives expected to change referral practice in the short to medium term and those that did not.

RESULTS

Overall, 38% of general practices were involved in at least one of four quality improvement activities (clinical audit, significant event analysis, use of risk assessment tools and development of practice plans). Against an overall 29% increase in urgent cancer referrals between 2009/10 and 2012/13, these practices had a significantly higher increase in referral rate, with reduced between-practice variation. There were no significant differences between the two groups in conversion, detection or emergency presentation rates. Key features of successful implementation at practice and network level reported by participants included leadership, organisational culture and physician involvement. Concurrent health service reforms created organisational uncertainty and limited the programme's effectiveness.

CONCLUSIONS

Specific primary care initiatives promoted by cancer networks had an additional and positive impact on urgent referrals for suspected cancer. Successful engagement with the programmes depended on effective and well-supported leadership by cancer networks and their general practitioner (GP) leads.

Optical reading aids for children and young people with low vision

BACKGROUND

Low vision in childhood is a significant barrier to learning and development, particularly for reading and education. Optical low vision aids may be used to maximise the child's functional vision. The World Health Organization (WHO) has previously highlighted the importance of the use of low vision aids in managing children with visual impairment across the world.

OBJECTIVES

To assess the effect of optical low vision aids on reading in children and young people with low vision.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to January 2015), EMBASE (January 1980 to January 2015), the Health Technology Assessment Programme (HTA) (www.hta.ac.uk/), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 8 January 2015.We also used manual searching to check the references listed in retrieved articles. Manufacturers of low vision aids were contacted to request any information about studies or research regarding their products.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) and quasi-RCTs where any optical low vision aid was compared to standard refractive correction in children and young people aged between 5 and 16 years of age with low vision as defined by the WHO. We planned to include within-person design studies where the order of presentation of devices was randomised.

DATA COLLECTION AND ANALYSIS

Two authors independently reviewed the search results for eligibility .

MAIN RESULTS

No studies met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

There is a lack of good quality evidence regarding the use of optical low vision aids in children and young people. As such, no implications for practice can be drawn. We believe future research should include functional outcome measures such as reading speed, accuracy and comprehension, as well as the effect of low vision aids on quality of life, in order to truly assess and compare the effect of these devices on a child's life and development.

Clinical Impact of Double Protease Inhibitor Boosting with Lopinavir/Ritonavir and Amprenavir as Part of Salvage Antiretroviral Therapy

PURPOSE

Double protease inhibitor (PI) boosting is being explored as a new strategy in salvage antiretroviral (ARV) therapy. However, if a negative drug interaction leads to decreased drug levels of either or both PIs, double PI boosting could lead to decreased virologic response. A negative drug interaction has been described between amprenavir (APV) and lopinavir/ritonavir (LPV/r). This observational cohort study assessed the virologic impact of the addition of APV to a salvage ARV regimen, which also contains LPV/r, compared to a regimen containing LPV/r alone.

METHOD

Patients initiated on a salvage ARV regimen that included LPV/r obtained from the expanded access program in Toronto, Canada, were evaluated. APV (600-1,200 mg bid) was added at the discretion of the treating physician.

RESULTS

Using multivariate Cox proportional hazards models, we found that the addition of APV to a LPV/r-containing salvage regimen was not significantly associated with time to virologic suppression (< 50 copies/mL; adjusted hazard ratio [HR] = 0.75, p =.12) or with time to virologic rebound (adjusted HR = 1.46, p =.34). Those patients who received higher doses of APV had an increased chance of virologic suppression (p =.03). In a subset of 27 patients, the median LPV C(trough) was significantly lower in patients receiving APV (p =.04), and the median APV C(trough) was reduced compared to reported controls.

CONCLUSION

Our data do not support an additional benefit in virologic reduction of double boosting with APV and LPV/r relative to LPV/r alone in salvage ARV therapy. Our study's limitations include its retrospective nature and the imbalance between the two groups potentially confounding the results. Although these factors were adjusted for in the multivariate analysis, a prospective randomized controlled trial is warranted to confirm our findings.

A multicentre phase III randomised controlled single-masked clinical trial evaluating the clinical efficacy and safety of light-masks at preventing dark-adaptation in the treatment of early diabetic macular oedema (CLEOPATRA): study protocol for a randomised controlled trial

Background

This study will evaluate hypoxia, as a novel concept in the pathogenesis of diabetic macular oedema (DMO). As the oxygen demand of the eye is maximum during dark-adaptation, we hypothesize that wearing light-masks during sleep will cause regression and prevent the development and progression of DMO. The study protocol comprises both an efficacy and mechanistic evaluation to test this hypothesis.

Method/Design

This is a phase III randomised controlled single-masked multicentre clinical trial to test the clinical efficacy of light-masks at preventing dark-adaptation in the treatment of non-central DMO. Three hundred patients with non-centre-involving DMO in at least one eye will be randomised 1:1 to light-masks and control masks (with no light) to be used during sleep at night for a period of 24 months. The primary outcome is regression of non-central oedema by assessing change in the zone of maximal retinal thickness at baseline on optical coherence tomography (SD-OCT). Secondary outcomes will evaluate the prevention of development and progression of DMO by assessing changes in retinal thickness in different regions of the macula, macular volume, refracted visual acuity and level of retinopathy. Safety parameters will include sleep disturbance. Adverse events and measures of compliance will be assessed over 24 months. Participants recruited to the mechanistic sub-study will have additional retinal oximetry, multifocal electroretinography (ERG) and microperimetry to evaluate the role of hypoxia by assessing and comparing changes induced by supplemental oxygen and the light-masks at 12 months.

Discussion

The outcomes of this study will provide insight into the pathogenesis of DMO and provide evidence on whether a simple, non-invasive device in the form of a light-mask can help prevent the progression to centre-involving DMO and visual impairment in people with diabetes.

Systematic review: the perceptions, diagnosis and management of irritable bowel syndrome in primary care--a Rome Foundation working team report

OBJECTIVE

To review studies on the perceptions, diagnosis and management of irritable bowel syndrome (IBS) in primary care.

METHODS

Systematic searches of PubMed and Embase.

RESULTS

Of 746 initial search hits, 29 studies were included. Relatively few primary care physicians were aware of (2-36%; nine studies) or used (0-21%; six studies) formal diagnostic criteria for IBS. Nevertheless, most could recognise the key IBS symptoms of abdominal pain, bloating and disturbed defaecation. A minority of primary care physicians [7-32%; one study (six European countries)] preferred to refer patients to a specialist before making an IBS diagnosis, and few patients [4-23%; three studies (two European, one US)] were referred to a gastroenterologist by their primary care physician. Most PCPs were unsure about IBS causes and treatment effectiveness, leading to varied therapeutic approaches and broad but frequent use of diagnostic tests. Diagnostic tests, including colon investigations, were more common in older patients (>45 years) than in younger patients [<45 years; five studies (four European, one US)].

CONCLUSIONS

There has been much emphasis about the desirability of an initial positive diagnosis of IBS. While it appears most primary care physicians do make a tentative IBS diagnosis from the start, they still tend to use additional testing to confirm it. Although an early, positive diagnosis has advantages in avoiding unnecessary investigations and costs, until formal diagnostic criteria are conclusively shown to sufficiently exclude organic disease, bowel investigations, such as colonoscopy, will continue to be important to primary care physicians.