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Serological studies revealed that toxoplasmosis has world wide distribution. Although the infection by "Toxoplasma gondii" is widely prevalent in humans and animals, the disease is uncommon and most of the acquired infections are asymptomatic. The important aspect of this parasitic infection is the probable danger of congenital transmission and its severe effects on the fetus. There have been many reports about the prevalence of anti-"T. gondii" antibody among different groups of people in Iran; however the epidemiological data in intellectual disability (ID) persons are rare. This study was performed to evaluate the seroprevalence of toxoplasmosis among the inhabitants of rehabilitation centers of northern Iran. A total of 336 serum samples (161 males, 175 females) were examined for the IgG antibodies by indirect immunofluorescense technique. First of all, 1:50 titer dilution was tested, in the cases of positive result, further dilutions (1:100, 1:200, 1:400, 1:800, 1:1600, and 1:3200) were prepared and the last dilution was recorded. Among 336 sera, 77.4% showed seropositivity by IFAT. The positive rates of males and females were 77.6% (125/161) and 80% (140/175), respectively. However, there were no significant differences between sexes. Comparing the age groups, the highest seropositive rate showed in 19 or higher, and their rates had a tendency to increase with age. Prevalence of the infection in 10 rehabilitation centers was not significant either. Nevertheless, our data (77.4%) in rehabilitation centers in northern Iran suggest that infection is the same as in many other reports in normal population in this area, therefore toxoplasmosis is not a major problem in rehabilitation centers of this geographical area.

Byline: G. Sadeghian, H. Ziaei, L. Bidabadi, A. Baghbaderani Background: Glucantime is regarded as the first-line treatment of cutaneous leishmaniasis (CL); however, failure to treatment is a problem in many [...]

Background. Recent biochemical and physiological investigations have focused on the fundament of mood disorders in thyroid dysfunction. The present study aimed to address depressive disorder in a sample of Iranian hypothyroid women compared to euthyroid individuals.

Abstract Background This cross-sectional study was conducted during summer 2008 at an academic ophthalmic hospital to assess patient satisfaction with care services and examine the impact of different dimensions on overall satisfaction. Findings Clients of ophthalmic services were selected by systematic random sampling. Overall satisfaction was measured as the primary outcome using a validated patient satisfaction questionnaire (PSQ-18). Different domains were evaluated using PSQ-18 (technical quality, interpersonal manner, communication, financial aspects, time spent for patients, convenience and accessibility); an additional domain, physical setting of the hospital, was evaluated by complementary questions. A general linear model was used to assess the adjusted impact of each quality dimension on the overall satisfaction. Accessibility and technical quality had the strongest association with the overall satisfaction. This regression model could predict an overall satisfaction of 60%. Conclusions In comparable settings, if care providers wish to improve the quality of health services from a patients' perspective, they should give priority to improving accessibility and technical quality. Further studies are recommended to discover complementary predictors in formation of overall satisfaction. Previous publication Some parts of this article are translated form Farsi originally published in Bina Journal of Ophthalmology. (2009; 14 (3): 289-297). The original work is at: http://binajournal.org/index.php/bina/article/view/96.

The article presents an abstract of the research paper "Effects of Prebiotic and Prebiotic Consumption on Serum Lipid Profile in Iranian Ross Broiler Chickens," by H. Ziaei and colleagues.

Background: Cataract, defined as an opacity of the lens in one or both eyes, is the leading cause of blindness worldwide. Cataract may initially be treated with new spectacles, but often surgery is required, which involves removing the cataract and placing a new artificial lens, usually made from hydrophobic acrylic. Recent advancements in intraocular lens (IOL) technology have led to the emergence of a diverse array of implantable lenses that aim to minimise spectacle dependence at all distances (near, intermediate, and distance). To assess the relative merits of these lenses, measurements of visual acuity are needed. Visual acuity is a measurement of the sharpness of vision at a distance of 6 metres (or 20 feet). Normal vision is 6/6 (or 20/20). The Jaegar eye card is used to measure near visual acuity. J1 is the smallest text and J2 is considered equivalent to 6/6 (or 20/20) for near vision., Objectives: To compare visual outcomes after implantation of trifocal intraocular lenses (IOLs) to those of extended depth of focus (EDOF) IOLs. To produce a brief economic commentary summarising recent economic evaluations that compare trifocal IOLs with EDOF IOLs., Search Methods: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE, Embase, and three trial registries on 15 June 2022. For our economic evaluation, we also searched MEDLINE and Embase using economic search filters to 15 June 2022, and the NHS Economic Evaluation Database (EED) from 1968 up to and including 31 December 2014. We did not use any date or language restrictions in the electronic searches., Selection Criteria: We included studies comparing trifocal and EDOF IOLs in adults undergoing cataract surgery. We did not include studies involving people receiving IOLs for correction of refractive error alone (or refractive lens exchange in the absence of cataract)., Data Collection and Analysis: We used standard Cochrane methods. Two review authors working independently selected studies for inclusion and extracted data from the reports. We assessed the risk of bias in the studies, and we assessed the certainty of the evidence using the GRADE approach., Main Results: We included five studies that compared trifocal and EDOF lenses in people undergoing cataract surgery. Three trifocal lenses (AcrySof IQ PanOptix, ATLISA Tri 839MP, FineVision Micro F) and one EDOF lens (TECNIS Symfony ZXR00) were evaluated. The studies took place in Europe and North America. Follow-up ranged from three to six months. Of the 239 enroled participants, 233 (466 eyes) completed follow-up and were included in the analyses. The mean age of participants was 68.2 years, and 64% of participants were female. In general, the risk of bias in the studies was unclear as methods for random sequence generation and allocation concealment were poorly reported, and we judged one study to be at high risk of performance and detection bias. We assessed the certainty of the evidence for all outcomes as low, downgrading for the risk of bias and for imprecision. In two studies involving a total of 254 people, there was little or no difference between trifocal and EDOF lenses for uncorrected and corrected distance visual acuity worse than 6/6. Sixty per cent of participants in both groups had uncorrected distance visual acuity worse than 6/6 (risk ratio (RR) 1.06, 95% confidence intervals (CI) 0.88 to 1.27). Thirty-one per cent of the trifocal group and 38% of the EDOF group had corrected distance visual acuity worse than 6/6 (RR 1.04, 95% CI 0.78 to 1.39). In one study of 60 people, there were fewer cases of uncorrected near visual acuity worse than J2 in the trifocal group (3%) compared with the EDOF group (30%) (RR 0.08, 95% CI 0.01 to 0.65). In two studies, participants were asked about spectacle independence using subjective questionnaires. There was no evidence of either lens type being superior. One further study of 60 participants reported, "overall, 90% of patients achieved spectacle independence", but did not categorise this by lens type. All studies included postoperative patient-reported visual function, which was measured using different questionnaires. Irrespective of the questionnaire used, both types of lenses scored well, and there was little evidence of any important differences between them. Two studies included patient-reported ocular aberrations (glare and halos). The outcomes were reported in different ways and could not be pooled; individually, these studies were too small to detect meaningful differences in glare and halos between groups. One study reported no surgical complications. Three studies did not mention surgical complications. One study reported YAG capsulotomy for posterior capsular opacification (PCO) in one participant (one eye) in each group. One study reported no PCO. Two studies did not report PCO. One study reported that three participants (one trifocal and two EDOF) underwent laser-assisted subepithelial keratectomy (LASEK) to correct residual myopic refractive error or astigmatism. One study reported a subset of participants who were considering laser enhancement at the end of the study period (nine trifocal and two EDOF). Two studies did not report laser enhancement rates. No economic evaluation studies were identified for inclusion in this review., Authors' Conclusions: Distance visual acuity after cataract surgery may be similar whether the lenses implanted are trifocal IOLs or EDOF (TECNIS Symfony) IOLs. People receiving trifocal IOLs may achieve better near vision and may be less dependent on spectacles for near vision. Both lenses were reported to have adverse subjective visual phenomena, such as glare and halos, with no meaningful difference detected between lenses., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Background: Dislocated IOL exchange conventionally involves manipulation within the anterior chamber which risks secondary injury to anterior chamber structures. We describe and evaluate a 4-haptic IOL rescue technique that avoids entering the anterior chamber and thus minimizes post operative inflammation, astigmatism and recovery time relative to conventional IOL explantation and replacement techniques., Methods: Retrospective, non-randomized, interventional study of all patients undergoing 4-haptic IOL rescue performed by two independent vitreoretinal surgeons at a single UK centre over two years., Surgical Technique: A limited peritomy is performed with four 25-gauge scleral ports placed to enable use of two forceps, an infusion and a chandelier. A further four 27-gauge sclerotomies are symmetrically placed on the nasal and temporal sclera at 3 mm from the limbus with a 5 mm vertical separation on either side. A pars plana vitrectomy is performed followed by chandelier illuminated, bimanual cleaning of the dislocated IOL using 27-gauge serrated forceps. Gore-tex sutures are threaded through the IOL islets within the vitreous cavity and externalized through the sclerotomies for scleral re-fixation followed by conjunctival closure., Results: Seven patients underwent IOL recycling with Gore-Tex suture scleral re-fixation. All procedures were successful in repositioning the IOLs, with all patients satisfied with post-operative outcome. Mean (standard deviation) time to IOL dislocation was 13 (3) years. Median visual acuity significantly improved post-operatively from 0.85 logMAR (Interquartile Range [IQR]: 0.2-2.1) to 0.07 (0.02-0.60) logMAR (p = 0.02). No significant post-operative complications were noted apart from persistent cystoid macular oedema in one patient non-compliant with post-operative treatment., Conclusions: Transscleral refixation using Gore-Tex suture is an effective, safe and practical approach in the management of dislocated 4-piece IOLs., (© 2024. The Author(s).)

Purpose: To compare SF 6 relative with C 2 F 6 in the anatomical and functional outcomes following pars plana vitrectomy for uncomplicated primary pseudophakic rhegmatogenous retinal detachment with inferior causative breaks., Methods: This is a retrospective, comparative study on eyes with pseudophakic rhegmatogenous retinal detachment with inferior causative breaks that had small-gauge pars plana vitrectomy repair using SF 6 and C 2 F 6 tamponade between 2011 and 2020 at a tertiary centre in the United Kingdom. Primary outcome was single surgery anatomical success, and the secondary outcome was best-corrected visual acuity. Propensity score matching, using preoperative findings as covariates to account for relevant confounders, was performed., Results: From 162 pseudophakic rhegmatogenous retinal detachment eyes with inferior causative breaks, the median (interquartile range) follow-up was 82 (52-182) days. The single surgery anatomical success was 156 (96.3%) overall: 47 of 47 (100.0%) and 109 of 115 (94.8%) in the SF 6 and C 2 F 6 groups, respectively ( P = 0.182). Relative to the SF 6 group, the C 2 F 6 group had a higher mean number of tears (SF 6 : 3.1[2.0], C 2 F 6 : 4.5[2.7], P = 0.002) and greater retinal detachment extent (SF 6 : 5.3[2.9], C 2 F 6 : 6.2[2.6] clock hours, P = 0.025). Following propensity score matching analysis, 80 eyes were matched with 40 in each group to homogenize preoperative factors. No significant difference was found in single surgery anatomical success and best-corrected visual acuity between the groups following propensity score matching., Conclusion: Primary pars plana vitrectomy with gas tamponade leads to a high single surgery anatomical success rate in uncomplicated pseudophakic rhegmatogenous retinal detachment with inferior causative breaks with no additional benefit associated with long-acting tamponade when comparing C 2 F 6 with SF 6 .

Cleft lip and/or palate (CLP) is a prevalent congenital craniofacial abnormality that can lead to difficulties in eating, speaking, hearing, and psychological distress. The traditional approach for treating CLP involves bone graft surgery, which has limitations, post-surgical complications, and donor site morbidity. However, regenerative medicine has emerged as a promising alternative, employing a combination of stem cells, growth factors, and scaffolds to promote tissue regeneration. This review aims to provide a comprehensive overview of stem cell-based regenerative approaches in the management of CLP. A thorough search was conducted in the Medline/PubMed and Scopus databases, including cohort studies, randomized controlled trials, case series, case controls, case reports, and animal studies. The identified studies were categorized into two main groups: clinical studies involving human subjects and in vivo studies using animal models. While there are only a limited number of studies investigating the combined use of stem cells and scaffolds for CLP treatment, they have shown promising results. Various types of stem cells have been utilized in conjunction with scaffolds. Importantly, regenerative methods have been successfully applied to patients across a broad range of age groups. The collective findings derived from the reviewed studies consistently support the notion that regenerative medicine holds potential advantages over conventional bone grafting and represents a promising therapeutic option for CLP. However, future well-designed clinical trials, encompassing diverse combinations of stem cells and scaffolds, are warranted to establish the clinical efficacy of these interventions with a larger number of patients., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: To investigate the anatomical and functional outcomes and specifically, the effect of 360-degree barrier-laser, in pars plana vitrectomy (PPV) for primary pseudophakic rhegmatogenous retinal detachment (PRD)., Methods: We conducted a single-centre retrospective, continuous and comparative study on eyes that had undergone PPV with focal-retinopexy (laser or cryotherapy) versus 360-laser for PRD repair between 2011-2020 at a single tertiary vitreoretinal centre in the UK. Primary outcomes were single surgery anatomical success (SSAS) rate and final postoperative visual acuity (VA). Multivariable regression covariates for primary re-detachment included age, gender, onset-of-detachment, pre-operative VA, ocular co-morbidities, macula-status, majority inferior (vs superior) PRD, number-of-tears and PRD extent (in clock-hours), 360-laser barricade, and perfluorocarbon liquid (PFCL) use. For VA gain, primary re-detachment was added as a covariate., Results: We included 467 eyes with a mean follow-up of 388 (161) days. The SSAS was 444/467 (95.1%) overall, and 351/370 (94.9%) and 93/97 (95.9%) in focal-retinopexy and 360-laser groups, respectively (p = 0.798). Compared to the focal-retinopexy group, the 360-laser group had significantly worse post-operative VA but similar logMAR gain (p = 0.812). A multivariable binary logistic regression found that only PFCL use was linked with increased primary re-detachment (OR:5.32 [p = 0.048]) and 360-laser did not contribute to increased SSAS. A multivariable linear regression analysis showed that poor logMAR gain was significantly associated with better pre-operative logMAR, ocular co-morbidities, greater PRD extent, use of 360-laser and primary re-detachment. However, when excluding macula-off RD (n = 211), 360-laser was no longer significant (p = 0.088)., Conclusions: Prophylactic 360-laser does not seem to impact on SSAS and functional outcomes following PPV for primary PRD., (© 2023. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: To present a new technique to treat refractory retinal detachment secondary to optic disk pit., Methods: An interventional case report., Results: A 25-year-old man with congenital optic disk pit had two failed vitrectomies involving laser around the optic disk, internal limiting membrane peel and flap to plug the disk pit, and gas tamponade to reattach the retina. With all options running out, a further vitrectomy with autologous retinal transplant and silicone oil tamponade was performed to treat the refractory serous retinal detachment; the silicone oil was removed at 6 weeks after the last procedure. The retina remained successfully attached at 6 months postsurgery with the patient maintaining his baseline visual acuity., Conclusion: The use of autologous retinal transplant is a new approach to treat refractory retinal detachment secondary to congenital optic disk anomalies, and adds to our options of dealing with this complex condition when first-line approaches have failed.

Purpose: To report the contribution to carbon dioxide equivalent mass [CO 2 EM] of various types of VR surgery performed across three tertiary referral centres, according to their indication and fluorinated gas used. We secondarily reported on the difference in tamponade choice, and CO 2 EM between the different centres., Materials: Retrospective, continuous, comparative multicentre study of all procedures using fluorinated gases between 01/01/17-31/12/20 at the Manchester Royal Eye Hospital and Birmingham and Midland Eye Centre, and between 01/01/19-31/12/2020 at the University Hospitals Coventry and Warwickshire., Results: Across 4877 procedures, the use of fluorinated gases produced 284.2 tonnes (71.2 tonnes annually) CO 2 EM; an annual consumption of 30,330 l of gasoline. Rhegmatogenous-retinal-detachment (RRD) and macular hole repair had the highest CO 2 EM by indication, accounting for 191.4 tonnes CO 2 EM (67.3%) and 28.6 tonnes CO 2 EM (10.1%); a mean 60.0 kg and 32.0 kg of CO 2 EM produced per surgery respectively. The use of fluorinated gases and their respective CO 2 EM contributions were significantly different across all three centres (p < 0.001) for all indications. SF 6, despite being used in 1883 procedures (38.6%), contributed to 195.5 tonnes CO 2 EM (68.8%). Relative to C 2 F 6 , procedures using C 3 F 8 and SF 6 produced 1.9 and 4.4 times more CO 2 EM., Conclusion: We demonstrated that SF 6 causes significantly higher carbon emissions relative to C 2 F 6 and C 3 F 8 with RRD and macular hole repair having the greatest environmental impact. We also reported large variations between different large VR centres in fluorinated gas use, and therefore in carbon emission contributions depending on indications for surgery. Evidence-based protocols might help in making VR surgery "greener"., (© 2022. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

The current review aimed to assess the reliability and efficacy of tissue-engineered composite grafts in the reconstruction of large maxillofacial defects resulting from trauma or a benign pathologic disease. A systematic review of the literature was conducted using PubMed/Medline, Embase, and Scopus up to March 2022. The eligibility criteria included patients who had been treated with composite allogeneic tissue engineering for immediate/delayed reconstruction of large maxillofacial defects with minimum/no bone harvesting site. In the initial search, 2614 papers were obtained, and finally, 13 papers were eligible to be included in the current study. Most included papers were case reports or case series. A total of 144 cases were enrolled in this systematic review. The mean age of the patients was 43.34 (age range: 9-89). Most studies reported a successful outcome. Bone tissue engineering for the reconstruction and regeneration of crucial-sized maxillofacial defects is an evolving science still in its infancy. In conclusion, this review paper and the current literature demonstrate the potential for using large-scale transplantable, vascularized, and customizable bone with the aim of reconstructing the large maxillofacial bony defects in short-term follow-ups.

Craniofacial morphogenesis requires complex interactions involving different tissues, signaling pathways, secreted factors and organelles. The details of these interactions remain elusive. In this study, we have analyzed the molecular mechanisms and homeostatic cellular activities governing soft palate development to improve regenerative strategies for individuals with cleft palate. We have identified canonical Wnt signaling as a key signaling pathway primarily active in cranial neural crest (CNC)-derived mesenchymal cells surrounding soft palatal myogenic cells. Using Osr2-Cre;β-cateninfl/fl mice, we show that Wnt signaling is indispensable for mesenchymal cell proliferation and subsequently for myogenesis through mediating ciliogenesis. Specifically, we have identified that Wnt signaling directly regulates expression of the ciliary gene Ttll3. Impaired ciliary disassembly leads to differentiation defects in mesenchymal cells and indirectly disrupts myogenesis through decreased expression of Dlk1, a mesenchymal cell-derived pro-myogenesis factor. Moreover, we show that siRNA-mediated reduction of Ttll3 expression partly rescues mesenchymal cell proliferation and myogenesis in the palatal explant cultures from Osr2-Cre;β-cateninfl/fl embryos. This study highlights the role of Wnt signaling in palatogenesis through the control of ciliary homeostasis, which establishes a new mechanism for Wnt-regulated craniofacial morphogenesis., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)

The South River located in the city of Waynesboro, Virginia, contains mercury (Hg) contamination due to historical releases from an industrial facility operating between 1929 and 1950. In 2015, two sampling events were conducted in two of the contaminated bank regions (Constitution Park and North Park) to evaluate non-particulate total mercury (THg) and methylmercury (MeHg) concentrations in bank interstitial waters during river base flows and during bank drainage after flooding events. Porewater THg and MeHg at the bank-water interface were measured using diffusive gradient in thin-film devices (DGTs). The results showed THg mercury concentrations during bank drainage were approximately a factor of 3 higher than during base flow conditions. To have a better understanding of the parameters that control Hg leaching, a series of laboratory experiments were designed using South River sediments. The field and laboratory assessment showed that drainage/inundation cycles can lead to high THg concentration leachate from contaminated sediment due to increased partitioning from solids under oxic bank conditions and mobilization by the drainage waters. The results also demonstrated that methyl mercury concentrations at the bank-water interface are highest under base flow when conditions are more reduced due to the absence of oxic water exchange with the surface water. A remedial approach was implemented involving partial removal of surficial sediments and placement of biochar (to reduce non-particulate THg) and an armoring layer (to reduce erosion). DGT Measurements after bank stabilization showed THg decreased by a factor of ~200 and MeHg concentration by a factor of more than 20.

Purpose: To investigate the direct contribution to carbon emissions of fluorinated gases used in all vitreoretinal (VR) procedures utilizing gas tamponade and assess the respective carbon footprint of the three different gas delivery systems., Design: A multicenter, retrospective, environmental impact study., Methods: All VR procedures using fluorinated gases between 2017 to 2020 at the Manchester Royal Eye Hospital (MREH) and Birmingham and Midland Eye Centre (BMEC) (the second and third largest VR centers in the UK), and between 2019 to 2020 at the University Hospitals Coventry and Warwickshire (UHCW) were included. CO 2 equivalent mass (CO 2 EM) was calculated from the mass of each gas used, according to the Intergovernmental Panel on Climate Change., Results: A total of 4877 (1883 SF 6 [38.6%], 2096 C 2 F 6 [43.0%], and 897 C 3 F 8 [18.4%]) procedures were analyzed. UHCW and BMEC utilized single-use 30 mL and 75 mL cannisters, respectively. MREH used four cylinders of each gas over 4 years (2 kg SF 6 , 1 kg C 2 F 6 , 1 kg C 3 F 8 ). Mean CO 2 EM per patient was: MREH 111.8 kg, BMEC 7.5 kg, and UHCW 2.7 kg. For MREH and BMEC, the CO 2 EM was 73.4 metric tons annually (if all cases were performed with i) 30 mL: 3.7 tons and ii) cylinders: 148.0 tons, x 40-fold difference), equating to 599,400 (30,500-1.2 million) km travelled by a passenger car. The current use of SF 6 in VR surgery accounts for 0.11% of total SF6 use; if 30 mL cylinders were exclusively used in the UK, this could be lowered to 0.01%., Conclusions: This study highlights the significant waste associated with large gas cylinders and demonstrated that 30 mL cannisters can lead to a marked reduction in carbon emissions, even after accounting for the increased carbon footprint involved in their manufacture and disposal., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Purpose: To report the potential reduction of carbon emissions by utilising air-tamponade (AT), where possible, instead of fluorinated gases in the management of rhegmatogenous retinal detachment (RRD). We compared the carbon CO2 emissions produced at two large tertiary referral vitreoretinal (VR) centres where RRD are exclusively repaired using fluorinated gases to a tertiary VR mass of each gas used according to the Intergovernmental Panel on Climate Change., Materials and Methods: Retrospective, continuous, comparative multicentre study of all procedures using fluorinated gases between 01/01/17-31/12/20 at the Manchester Royal Eye Hospital (MREH) and Birmingham and Midland Eye Centre (BMEC), and between 01/01/19-31/12/2020 at the University Hospitals Coventry and Warwickshire (UHCW)., Results: We report on 3,239 (SF6:1,415 [43.7%], C2F6:1,235 [38.1%], C3F8:541 [16.7%], Air:48 [1.5%]) procedures. UHCW and BMEC utilise single use 30ml and 75ml cannisters, respectively and MREH use multi-use gas cylinders. UHCW used AT in 48 (70%) of RRD repairs. Mean equivalent mass CO2/patient was MREH:115.9kg, BMEC:7.9kg and UHCW:1.9kg. If assuming all centres used 30ml cannisters, the mean equivalent mass CO2/patient was MREH:3.5 kg, BMEC:3.1kg and UHCW:1.9kg. AT enabled UHCW to greatly reduce the need for the most environmentally damaging SF6 gas, leading to lower CO2 emissions by 47.0% and 41.1% compared to MREH and BMEC, respectively., Conclusion: We demonstrate how AT vs. the fluorinated gases can reduce in carbon footprint in the management of RRD. Further studies are required to determine the most 'environment-friendly' intraocular tamponade without compromising patient outcomes centre that also routinely employs AT in selected RRD cases., Competing Interests: The authors have declared that no competing interests exist.