Letter to the Editor concerning «A systematic review of controlled trials on visual stress using intuitive overlays or colorimeter» / Carta al Editor en relación a «Revisión sistemática de ensayos controlados sobre estrés visual utilizando filtros intuitivos o colorímetro»

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The effect of coloured overlays and lenses on reading: a systematic review of the literature.

PURPOSE: There are many anecdotal claims and research reports that coloured lenses and overlays improve reading performance. Here we present the results of a systematic review of this literature and examine the quality of the evidence. METHODS: We systematically reviewed the literature concerning the effect of coloured lenses or overlays on reading performance by searching the PsychInfo, Medline and Embase databases. This revealed 51 published items (containing 54 data sets). Given that different systems are in use for issuing coloured overlays or lenses, we reviewed the evidence under four separate system headings (Intuitive, Irlen, Harris/Chromagen and Other), classifying each published item using the Cochrane Risk of Bias tool. RESULTS: Although the different colour systems have been subjected to different amounts of scientific scrutiny, the results do not differ according to the system type, or whether the sample under investigation was classified as having visual stress (or a similarly defined condition), reading difficulty, or both. The majority of studies are subject to 'high' or 'uncertain' risk of bias in one or more key aspects of study design or outcome, with studies at lower risk from bias providing less support for the benefit of coloured lenses/overlays on reading ability. While many studies report improvements with coloured lenses, the effect size is generally small and/or similar to the improvement found with a placebo condition. We discuss the strengths and shortcomings of the published literature and, whilst acknowledging the difficulties associated with conducting trials of this type, offer some suggestions about how future trials might be conducted. CONCLUSIONS: Consistent with previous reviews and advice from several professional bodies, we conclude that the use of coloured lenses or overlays to ameliorate reading difficulties cannot be endorsed and that any benefits reported by individuals in clinical settings are likely to be the result of placebo, practice or Hawthorne effects.

Infantile Periocular Haemangioma: Optimising the Therapeutic Response.

Oral propranolol is now established as the first-line treatment for infantile haemangiomas, and used in up to 20 % of all cases. Propranolol use in infants is most commonly instigated in a controlled environment to monitor for potential serious adverse events such as hypoglycaemia and hypotension. Two test doses are recommended, the first one of 300 µg/kg followed by 2-hourly monitoring. On the subsequent day, a further dose of 650 µg/kg is administered with the same monitoring. A dose of 2 mg/kg divided into three is started from the next day. Parents/carers need to be warned of common adverse effects, of which disturbed sleep is the commonest. Treatment is recommended for up to a year to avoid rebound growth and the need to restart the treatment.

Global Surgery 2030: a roadmap for high income country actors.

The Millennium Development Goals have ended and the Sustainable Development Goals have begun, marking a shift in the global health landscape. The frame of reference has changed from a focus on 8 development priorities to an expansive set of 17 interrelated goals intended to improve the well-being of all people. In this time of change, several groups, including the Lancet Commission on Global Surgery, have brought a critical problem to the fore: 5 billion people lack access to safe, affordable surgical and anaesthesia care when needed. The magnitude of this problem and the world's new focus on strengthening health systems mandate reimagined roles for and renewed commitments from high income country actors in global surgery. To discuss the way forward, on 6 May 2015, the Commission held its North American launch event in Boston, Massachusetts. Panels of experts outlined the current state of knowledge and agreed on the roles of surgical colleges and academic medical centres; trainees and training programmes; academia; global health funders; the biomedical devices industry, and news media and advocacy organisations in building sustainable, resilient surgical systems. This paper summarises these discussions and serves as a consensus statement providing practical advice to these groups. It traces a common policy agenda between major actors and provides a roadmap for maximising benefit to surgical patients worldwide. To close the access gap by 2030, individuals and organisations must work collectively, interprofessionally and globally. High income country actors must abandon colonial narratives and work alongside low and middle income country partners to build the surgical systems of the future.

Surrendering control, or nothing to lose: Parents' preferences about participation in a randomised trial of childhood strabismus surgery.

BACKGROUND: Intermittent exotropia is the most common form of divergent strabismus (squint) in children. Evidence regarding its optimum management is limited. A pilot randomised controlled trial has recently been completed (Surgery versus Active Monitoring in Intermittent Exotropia trial) to determine the feasibility of a full randomised controlled trial. PURPOSE: To identify drivers for and barriers against parents' participation in Surgery versus Active Monitoring in Intermittent Exotropia and to seek their views on information received, the need for randomisation, and enhancing acceptability. METHODS: Multiple method qualitative study using semi-structured telephone interviews to explore parents' motivations and trial screening logs to provide an indication of common barriers. Exploratory thematic analysis identified key themes. RESULTS: A total of 48 interviews were conducted (14 participants; 34 non-participants). Barriers included no desire for surgery/preference to 'wait and see', wanting surgery immediately, feeling uncomfortable about 'surrendering control' over decision-making/being managed 'at random', lack of confidence in the effectiveness of surgery, believing the risks outweighed the benefits, and lack of trust. Drivers included desiring surgery, 'nothing to lose', benefits offsetting the risks, and being in a trial would result in better care. Some also mentioned 'doing their bit' for research. Suggestions for enhancing acceptability included allowing choice of treatment group, giving more time for decision-making, expanding on information given, and improving communication. Many felt the necessity of randomisation was adequately explained, but there was some indication that it was misunderstood. Information extracted from the screening logs of 80/89 eligible non-participants indicated the most prevalent barrier was not wanting surgery/preferring to observe (56%), followed by desiring surgery straightaway (15%). Opposition to randomisation/wanting to retain control was recorded in 9% of cases as was the belief that the child's squint was not severe enough to warrant surgery. LIMITATIONS: Interviews were not audio-recorded. Not all who consented to interview could be contacted, although the response/contact rate was good (48/62). A few parents did not provide reasons for refusing the trial. CONCLUSION: Opposition to surgery and concerns about surrendering control were common obstacles to participation, whereas parents keen for their child to undergo the operation but happy to defer tended to embrace a 'nothing to lose' attitude. Many non-participants would have consented if allowed to choose group, although most of these would have chosen observation. While most parents felt happy with information given and that randomisation was adequately explained, it is of concern that there may be some misunderstanding, which should be addressed in any trial. These findings will inform future trials in childhood exotropia, for example, consideration of preference arms and improving communication. Lessons learnt from the Surgery versus Active Monitoring in Intermittent Exotropia trial could prove valuable to paediatric and surgical trials generally.

Severe complications of strabismus surgery.

PURPOSE: To determine the type, incidence, and clinical outcomes of severe complications from strabismus surgery in the United Kingdom. METHODS: Cases were identified prospectively through a national surveillance unit between September 1, 2008, and August 31, 2010. Questionnaire data were requested at the time of the complication recognition and at 6 months' follow-up. Outcome was graded I to V, with a poor or very poor outcome meaning either loss of corrected visual acuity or primary position double vision. RESULTS: A total of 60 completed reports of adverse events and complications were received during the study period. During the same time approximately 24,000 strabismus surgeries were performed in the United Kingdom, yielding an overall incidence of 1 in 400 operations (95% binomial confidence, 1 per 333-500 operations). The most common reported complication was perforation of the globe (19 [0.08%]), followed by a suspected slipped muscle (16 [0.067%]), severe infection (14 [0.06%]), scleritis (6 [0.02%]), and lost muscle (5 [0.02%]). Overall, complications were reported in adults and children in equal numbers; however, scleritis was significantly more common in adults. A poor or very poor clinical outcome was recorded as 1 operation per 2,400. CONCLUSIONS: This study provides an assessment of the overall risks associated with strabismus surgery in the United Kingdom. Complications with the potential for a poor outcome are relatively common, but the final clinical outcome is good in the majority of cases.

International surgery: the development of postgraduate surgical training in Guyana.

BACKGROUND: Like many developing countries, Guyana has a severe shortage of surgeons. Rather than rely on overseas training, Guyana developed its own Diploma in Surgery and asked for assistance from the Canadian Association of General Surgeons (CAGS). This paper reviews the initial results of Guyana's first postgraduate training program. METHODS: We assisted with program prerequisites, including needs assessment, proposed curriculum, University of Guyana and Ministry of Health approval, external partnership and funding. We determined the outputs and outcomes of the program after 2 years, and we evaluated the impact of the program through a quantitative/qualitative questionnaire administered to all program participants. RESULTS: Five residents successfully completed the 2-year program and are working in regional hospitals. Another 9 residents are in the training program. Twenty-four modules or short courses have been facilitated, alternating Guyanese with visiting Canadian surgical faculty members coordinated through CAGS. A postgraduate structure, including an Institute for Health Sciences Education and Surgical Postgraduate Education Committee, has been developed at the Georgetown Public Hospital Corporation (GPHC). An examination structure similar to Canada's has been established. Hospital staff morale is greater, surgical care is more standardized and academic opportunities have been enhanced at GPHC. Four regional hospitals have welcomed the new graduates, and surgical services have already improved. Canadian surgeons have a greater understanding of and commitment to surgical development in low-income countries. CONCLUSION: Guyana has proven that, with visiting faculty assistance, it can mount its own postgraduate training suitable to national needs and will provide a career path to encourage its own doctors to remain and serve their country.

Conjunctival granuloma caused by surgical talc.

Talc from surgical gloves has been known to be a cause of granulomas within the surgical cavity. We report a case in which recurrent conjuntival inflammation was found to be caused by talc.

Fascicular keratitis in children: can corneal phlycten be mobile?

Phlyctenulosis is an uncommon condition that usually affects children's cornea or conjunctiva. Although its exact aetiology is unknown, it is thought to be a non-specific delayed hypersensitivity reaction to staphylococci or other bacterial, fungal or parasitic antigens. Herein a case of a 3.5-year-old boy with corneal phlyctenulosis is described in whom the phlycten appears to have has migrated from its origin at the limbus to the central cornea (fascicular keratitis) and become visually disabling. At his last follow up he was asymptomatic. Some stromal scarring of the right cornea remained and his visual acuity improved in both eyes following treatment.

Review of a Canadian forum on international surgery: the Bethune Round Table.

The Bethune Round Table is an annual conference on international surgery that is unique in North America. Hosted by the Office of International Surgery at the University of Toronto, the conference provides a forum for profiling the global realities of surgical need, particularly as they relate to vulnerable and disadvantaged people of low-income countries. The 2004 Bethune Round Table, drawing on input from 4 continents, highlighted "emerging directions". Presentations and discussions focused on the themes of current surgical realities, the implications for surgical education, the role of specialized surgical services and the function of surgical partnerships.

Tied and tidy: closing the conjunctiva over adjustable sutures.

BACKGROUND: Adjustable sutures have revolutionized strabismus surgery. Numerous techniques have been described that aim to facilitate postoperative adjustment. Nevertheless, some sort of procedure is always necessary following adjustable suture surgery and has to be arranged within 24 hours. Where no adjustment is required, the muscle needs to be secured at the existing position and the conjunctiva, sometimes left on a loop, has to be tidied up and sutured. METHODS: As fewer than half of the operated on eyes need a final adjustment, we describe a technique whereupon the muscle is left on a loop and the conjunctiva is closed over it with two interrupted polyglactin 910 sutures. If an adjustment is deemed necessary, one of the sutures has to be cut and replaced at the end of the procedure. When the result of squint surgery is satisfactory and no muscle movement is needed, no further manipulation of the conjunctiva is required. CONCLUSIONS: In a series of 17 patients, we have found this technique to be excellent for patient comfort and time efficiency. We have not encountered any muscle slippage. We think that the ease of postoperative management may tend to bias the surgeon against adjustment.

Effect of emergent presentation on outcome from rectal cancer management.

BACKGROUND: We have previously reported outcomes for all rectal cancers in BC in 1996. We found that our local recurrence rates and survival were suboptimal relative to current standards in recent literature. METHODS: In this retrospective, population-based study, we report the influence of emergent presentation (obstruction, perforation, massive hemorrhage) on outcomes, types of surgical procedures and use of staging investigations, and use of adjuvant radiation and chemotherapy. RESULTS: There were 452 invasive adenocarcinomas of the rectum of which 45 were emergent and 407 nonemergent. Disease-specific survival at 4 years for emergent and nonemergent stage II cancers were 66% versus 80%, respectively, and for stage III cancers, 60% versus 73%, respectively (P <0.04). Local recurrence rates at 4 years for emergent and nonemergent stage II cancers were 20% versus 15%, respectively, and for stage III cancers, 70% and 20%, respectively (P <0.05). Surgical resection more frequently involved a stoma for emergent (60%) than for nonemergent (35%) cases (P <0.01). Percent of patients having complete staging investigations were similar between emergent (42%) and nonemergent patients (39%). Adjuvant radiation was given in similar proportion to emergent (61%) and nonemergent (55%) patients. Adjuvant chemotherapy was given to a slightly higher proportion of emergent patients (63%) than nonemergent patients (43%). CONCLUSIONS: We conclude that outcome from rectal cancer management is worse for emergent than nonemergent presentation. Since there is no difference in use of staging investigations or adjuvant therapy, the difference in outcome is likely due to difference in surgical technique between emergent and nonemergent cases.

Effects of positive resection margin and tumor distance from anus on rectal cancer treatment outcomes.

PURPOSE: Rectal cancer outcome depends on stage, technical aspects of surgical excision, and use of adjuvant chemoradiation. Here, we examine effects of positive resection margin and tumor distance from the anus in stage 2 and 3 cancers on 4-year disease-specific survival and recurrence. METHODS: We reviewed all 495 rectal cancer patients registered in British Columbia in 1996. RESULTS: There were 481 cases analyzed: 29 in situ, 134 stage 1, 107 stage 2, 100 stage 3, 83 stage 4, and 28 unknown stage. Survival was significantly affected by presence of positive resection margin in stage 2 and 3 cancers, P = 0.0001. Lower tumor distance from the anus for stage 2 and 3 cancers worsened survival, P = 0.0007, and overall recurrence, P =0.016, but not local recurrence, P = 0.11. Adjuvant postoperative combined radiation and chemotherapy in stage 2 and 3 cancers significantly improved survival, P = 0.070 and local recurrence, P = 0.018, but not overall recurrence, P = 0.19. CONCLUSIONS: Presence of positive resection margin and tumor distance from the anus affect survival, local recurrence, and overall recurrence. Adjuvant postoperative combined radiation and chemotherapy improved our outcomes. Our local recurrence rates for rectal cancers are worse than currently reported standards of less than 10%. Improved surgical excision and use of adjuvant preoperative radiation and chemotherapy may improve outcome.