A survey of UK practice patterns in the delivery of intravitreal injections.

PURPOSE: To assess UK practice patterns related to the prescription of antibiotics before, during and after intravitreal injections, the location where injections are carried out and the qualifications of those administering the injections. METHODS: Every ophthalmology unit featured in the Royal College of Ophthalmologists (UK) training directory was contacted. A healthcare professional involved in giving intravitreal injections at each institution completed a questionnaire regarding local practice patterns. RESULTS: A response rate of 85% (115/136) was achieved. Seventy four percent of hospitals (85/115) gave take home antibiotics post intravitreal injection. Twenty three percent (26/115) of hospitals employed non-medical healthcare professionals to administer injections and 83% (96/115) administered intravitreal injections in a dedicated clean room as opposed to an operating theatre. CONCLUSION: Practice patterns for intravitreal injection vary considerably. Guidelines alone do not appear to be effective in reducing practices which are considered wasteful and other approaches need to be developed.

Social media use by patients with glaucoma: what can we learn?

PURPOSE: Much health-related information is available on the internet but its quality is known to be variable. This research aimed to analyse the ophthalmic content of social media platforms which has yet to be formally assessed. METHODS: Five online social media platforms were selected, the International Glaucoma Association (IGA) forum, Facebook, Twitter, YouTube and Patient Opinion.org.uk. A total of 3785 items were scraped from the sites, collated and analysed using simple thematic analysis by two coders. RESULTS: Fourteen themes were identified. The most commonly discussed topics included treatments, care experiences, promotions and support. Un-moderated sites contain more misleading information. Complementary therapies and treatments with a poor evidence base are presented more positively than established, evidence-based treatments. CONCLUSION: Online forums give patients a space to air questions, grievances, suggestions and to provide mutual support. The information they contain may be of use to physicians by flagging adverse drug reactions, areas for service improvement or topics about which patients require more information. There is a risk of exposure to misleading content which is heightened in un-moderated sites. Social media platforms may be an adjunct to current care models by providing a supportive and educational online community if these risks are understood.

What do patients with glaucoma think about personal health records?

PURPOSE: Putting patients in control of their records is one way of promoting patient centred care and patients with chronic health problems may benefit most from personal health records (PHRs). Glaucoma management is often complicated by incomplete understanding and poor adherence to treatment, two areas which a PHR may help to address. This study aimed to discover what patients with glaucoma think about PHRs and what type of information a glaucoma PHR should contain. METHODS: A consultation exercise using a focus group approach involving 71 participants was undertaken to discuss if a PHR would be useful and what it would be like. Narrative data were collected through written notes and an online forum in addition to transcripts of the focus group feedback session and individual interviews. Recordings were transcribed and analysed with simple thematic analysis facilitated by NVivo software (www.qsrinternational.com). RESULTS: The consultation exercise indicated enthusiasm for PHRs. Views varied on the best format, some participants strongly favoured electronic records and others preferred a low-tech, paper based format. A comprehensive dataset of 24 items was developed which highlighted areas which are not covered by existing guidance to developers. A model for how PHRs may be useful as an education tool in clinical practice was devised. CONCLUSIONS: Asking patients what they thought about a glaucoma PHR raised challenging questions and adds perspective to predominantly clinician led development. Listening and responding to such viewpoints is fundamental to developing more patient centred PHRs which may act both as health record and self-care educational tool to promote more holistic, efficient glaucoma care.

Superior oblique tuck-effectiveness in reducing vertical deviations when performed as a primary versus secondary procedure in superior oblique paresis.

PURPOSE: To quantify the effectiveness of superior oblique tuck (SOT) surgery in patients with a hyperdeviation secondary to superior oblique paresis (SOP). Surgical outcomes were compared in patients undergoing SOT surgery as a primary procedure with those who had previously undergone ipsilateral inferior oblique weakening surgery. METHODS: This retrospective study assessed surgical outcomes from all patients undergoing SOT surgery for SOP between 2012 and 2021 across 2 hospitals. The effectiveness of SOT surgery in reducing the hyperdeviation was assessed in the primary position (PP) and in contralateral elevation and depression. Results were compared between those undergoing primary SOT surgery with those who had previously undergone ipsilateral inferior oblique weakening surgery. RESULTS: A total of 60 SOT procedures were performed between 2012 and 2021. 7 were removed due to incomplete data. The remaining 53 cases experienced a mean reduction in hyperdeviation of 6.5 prism dioptres (PD), 6.7PD and 12.0PD in the PP, contralateral elevation and contralateral depression respectively. In eyes with previous IO weakening, the reduction of hyperdeviation was larger than in those eyes with no previous IO weakening surgery, with mean reductions of 8.0PD vs 5.2PD, 7.4PD vs 6.2PD and 12.4PD vs 11.6PD in the PP, contralateral elevation and contralateral depression respectively. CONCLUSION: SOT surgery is a safe and effective procedure with high patient satisfaction and resolution of symptoms in those patients with troublesome diplopia in downgaze secondary to SOP. This is true in both unoperated eyes and in those who have previously undergone inferior oblique weakening surgery.

Addressing the environmental sustainability of eye health-care delivery: a scoping review.

The demand for eye care-the most common medical speciality in some countries-is increasing globally due to both demographic change and the development of eye health-care services in low-income and middle-income countries. This expansion of service provision needs to be environmentally sustainable. We conducted a scoping review to establish the nature and extent of the literature describing the environmental costs of delivering eye-care services, identify interventions to diminish the environmental impact of eye care, and identify key sustainability themes that are not yet being addressed. We identified 16 peer-reviewed articles for analysis, all published since 2009. Despite a paucity of research evidence, there is a need for the measurement of environmental impacts associated with eye care to be standardised along with the methodological tools to assess these impacts. The vastly different environmental costs of delivering clinical services with similar clinical outcomes in different regulatory settings is striking; in one example, a phacoemulsification cataract extraction in a UK hospital produced more than 20 times the greenhouse gas emission of the same procedure in an Indian hospital. The environmental costs must be systematically included when evaluating the risks and benefits of new interventions or policies aimed at promoting safety in high-income countries.

What happens to intraocular pressure at high altitude?

PURPOSE: To investigate changes of intraocular pressure on ascent to high altitude. METHODS: The Apex 2 medical research expedition provided the opportunity to measure intraocular pressure (IOP) and central corneal thickness (CCT) in 76 healthy lowlanders. They all arrived in La Paz, Bolivia (altitude, 3700 m), where they spent 4 days before being driven more than 2 hours to the Cosmic Physics Laboratory at Chacaltaya (5200 m) where they stayed for 7 days. IOP and CCT were measured with a hand-held tonometer and ultrasound pachymetry on the first, third, and seventh days at 5200 m. Pre- and postexpedition CCT and postexpedition IOP readings at sea-level were also measured. RESULTS: IOP increased significantly from baseline after acute exposure to altitude before returning to baseline with time. IOP at baseline, change in IOP from baseline, and IOP at altitude did not predict symptoms of acute mountain sickness (AMS) or development of high-altitude retinopathy (HAR). CONCLUSIONS: Acute exposure to altitude caused a statistically significant but clinically insignificant increase in IOP. This finding may be partially explained by the change in CCT. IOP returned to baseline levels and possibly lower with prolonged exposure to altitude. Changes in IOP at altitude are not predictive of symptoms of acute mountain sickness (AMS) or development of high-altitude retinopathy (HAR).

Corneal thickness at high altitude.

PURPOSE: The eye, like other organs, is affected by the hypobaric hypoxia of high altitude. Corneal swelling is known to occur under hypoxic conditions at sea level, for instance when wearing contact lenses. The aim of this study was to measure central corneal thickness (CCT) in lowlanders ascending to altitude. METHODS: The Apex 2 medical research expedition provided the opportunity to measure CCT in 63 healthy lowlanders. The subjects arrived in La Paz, Bolivia (3700 m), where they spent 4 days acclimatizing before being driven over 2 hours to the Cosmic Physics Laboratory at Chacaltaya (5200 m), where they stayed for 7 days. CCT was measured in the early afternoon by using ultrasound pachymetry on the first, third, and seventh day at 5200 m and before and after the expedition at sea level. RESULTS: Mean CCT increased significantly from 543 microm at sea level to 561 microm on the first day at 5200 m (P < 0.001). This continued to increase to 563 microm on the third day and 571 microm on the seventh day but returned to 541 microm after descent to sea level. CONCLUSIONS: This study showed that altitude caused a significant increase in CCT in a large group of healthy lowlanders with normal corneas. This finding confirms the results of previous studies and is likely to be caused by endothelial dysfunction causing stromal swelling. This could potentially cause visual problems for high-altitude mountaineers among whom refractive surgery is popular.

High altitude and retinal detachment.

We describe the case of a 38-year-old man who presented with bilateral retinal detachments following a trek in Tibet during which time he took acetazolamide for prophylaxis of acute mountain sickness (AMS). This is the first time that retinal detachment has been described following a sojourn to high altitude. Acetazolamide has not been previously associated with retinal detachment when used for prophylaxis of AMS or indeed during its many ophthalmic applications. The patient made a good recovery following surgery, and we speculate that, although this could be coincidental and the patient did have risk factors for retinal detachment, the possibility of a causal link to high altitude should at least be entertained. We hypothesize that vitreous dehydration may have caused vitreoretinal traction and that hypobaric hypoxia may have changed the dynamic relationship between vitreous, retina, retinal pigment epithelium (RPE) and choroid, causing preexisting retinal holes to open, allowing subretinal fluid to accumulate and detach the retina.

The eye at altitude.

High altitude retinopathy (HAR) was first described in 1969 as engorgement of retinal veins with occasional papilloedema and vitreous hemorrhage. Since then various studies have attempted to define the incidence, etiology and significance of this phenomenon, usually with small numbers of subjects. Recently studies on relatively large groups of subjects in Nepal, Bolivia and Tibet have confirmed that the retinal vasculature becomes engorged and tortuous in all lowlanders ascending above 2500m. Sometimes this leads to hemorrhages, cotton wool spots and papilloedema, which is the pathological state better known as high altitude retinopathy. These studies have also shown a significant change in both corneal thickness and intraocular pressure at altitude. The retinal blood vessels are the only directly observable vascular system in the human body and also supply some of the most oxygen-demanding tissue, the photoreceptors of the retina. New techniques are being applied in both hypobaric chamber and field expeditions to observe changes in retinal function during conditions of hypobaric hypoxia. This work allows better advice to be given to lowlanders traveling to altitude either if they have pre-existing ocular conditions or if they suffer from visual problems whilst at altitude. This especially applies to the effect of altitude on refractive eye surgery and results of recent studies will be discussed so that physicians can advise their patients using the latest evidence. Retinal hypoxia at sea level accounts for the developed world's largest cause of blindness, diabetic retinopathy. The investigation of retinal response to hypobaric hypoxia in healthy subjects may open new avenues for treatment of this debilitating disease.

Polymorphisms in the P450 c17 (17-hydroxylase/17,20-Lyase) and P450 c19 (aromatase) genes: association with serum sex steroid concentrations and bone mineral density in postmenopausal women.

The CYP 17 and CYP 19 genes encode 17alpha-hydroxylase/17,20-lyase and aromatase, respectively, both involved in sex hormone synthesis. We investigated the association between 2 common polymorphisms in 1) the promoter region (T-->C substitution) of CYP 17, and 2) exon 3 (G-->A) of CYP 19, bone mineral density (BMD) and serum androgen/estradiol, in a case-control study of 252 postmenopausal women aged 64.5 +/- 9.2 yr (mean +/- SD). There was no significant difference in serum estradiol concentrations between cases (n = 136) and controls (n = 116). The CYP 19 genotype was significantly associated with serum estradiol (P = 0.002). Women with the AA genotype had higher serum estradiol concentrations compared with those with the GG genotype (P = 0.03). In older women, those with the CYP 19 GA and GG genotypes had an increased prevalence of osteoporosis (P = 0.04) and fractures (P = 0.003). We found no significant association between CYP 17 genotype and serum androgens and estradiol concentrations. However, a significant association was seen between BMD values at the femoral neck with CYP 17 genotype in cases (P = 0.04) and in the whole study population (P = 0.012). Subjects with the CC genotype had significantly lower BMD (mean +/- SD: TT, 0.7 +/- 0.16; CC, 0.6 +/- 0.08 g/cm(2); P = 0.006). In conclusion, both CYP 17 and CYP 19 are candidate genes for osteoporosis in postmenopausal women.

Reducing ineffective practice: challenges in identifying low-value health care using Cochrane systematic reviews.

OBJECTIVES: Despite international agreement that stopping low value practices will increase efficiency, identifying them is difficult and controversial. Opponents of centralized lists of low value practices stress that the actual problem is inappropriate low value use, and better targeting and implementation of treatment thresholds is needed. Our objective was to use Cochrane Reviews to identify low value practices to support local disinvestment decisions. METHODS: New or updated reviews were included if the authors concluded that the uncertain effectiveness of an intervention meant it should only be used in research, or that it was ineffective or harmful and should not be used. The reviews go through a production and quality assurance process, and are published as 'Cochrane Quality and Productivity topics' through the NHS Evidence website (http://www.library.nhs.uk/qipp/). RESULTS: Over a six-month period, 65 Cochrane reviews were processed by the National Institute for Health and Clinical Excellence (NICE). Of these, 28 identified potentially low value practices in the UK context. This was primarily due to a lack of randomized evidence of effectiveness, rather than robust evidence of a lack of effectiveness, or evidence of harm. CONCLUSIONS: Identifying low-value health care practices for local disinvestment (total or partial) is both practically and politically challenging, yet it is necessary to manage health budgets. This project identified that Cochrane Reviews can potentially identify low value health care practices. However, each review has to be reinterpreted for the UK context and additional analysis has to be undertaken to facilitate local implementation. Recommendations to improve the usability of systematic reviews are made.

Moving from PROMs to POEMs for glaucoma care: a qualitative scoping exercise.

PURPOSE: Patient-reported outcome measures (PROMs) are accepted widely as important outcomes in comparative effectiveness research. Over 30 PROMs have been described for use in glaucoma research, but their role in routine care is undefined. Our study explores the views of patients with glaucoma and their carers on the feasibility and content of a glaucoma PROM for use in day-to-day clinical practice. METHODS: Focus groups were held with 71 participants facilitated by 23 staff working in the field of ophthalmology. Comparisons were made among themes derived from this exercise using simple thematic analysis and currently available health-related quality of life (HRQoL) instruments. RESULTS: Participants were supportive of reporting their outcomes if the instrument was short, practical, and useful. Potential barriers to the use of PROMs, including bureaucratic overload and accessibility issues, were identified. Measuring health outcome and patient experience was important to participants. No freely available instrument covers all the domains identified, particularly knowledge and understanding. A novel instrument, a glaucoma patient-reported outcome and experience measure (POEM) is proposed. This addresses three aspects of outcome (fear of blindness, acceptability of treatment/side effects, and impact on daily life), and three aspects of experience (safety, respect, and understanding). CONCLUSIONS: Using PROMs routinely in the management of glaucoma presents significant challenges. Although current instruments (questionnaires) cover many of the participants' key domains, no single instrument covered them all. Further research is required to determine the feasibility (resources required), and validity and reliability of the proposed glaucoma POEM in clinical care.

Retinal vessel tortuosity in response to hypobaric hypoxia.

PURPOSE: Retinal vascular tortuosity is associated with retinopathy of differing etiologies, including hypertension, diabetes, and hypoxia. However, detailed understanding of the underlying pathophysiology is lacking. The aim of this study was to map changes in tortuosity associated with hypoxia at high altitude, and to determine the influence of sildenafil and an antioxidant preparation on altitude-induced tortuosity. METHODS: We measured the tortuosity of retinal vessels using a semi-automated method in 35 young, healthy subjects exposed to hypobaric hypoxia for 7 days at 5200 m, and compared the measurements to those from the same vessels at sea level. These subjects simultaneously took part in a randomized double-blind placebo-controlled trial of sildenafil and antioxidant. Comparison of tortuosity between these subgroups was performed. RESULTS: High altitude was associated with the development of retinal tortuosity in individual vessels. A nonsignificant trend suggests this is limited by prophylaxis with sildenafil or antioxidant. CONCLUSIONS: Retinal vessel tortuosity increases rapidly at high altitude. We suggest that retinal vessel tortuosity at altitude may result from increased sheer stress causing elongation of vessel segments and that this might be limited by agents that act to preserve nitric oxide dependent vasodilation. TRIAL REGISTRATION NUMBERS: NCT00664001, NCT00627965.

Off-axis digital flash photography: a common cause of artefact leukocoria in children.

Leukocoria, a presenting sign in several significant pediatric ocular conditions, can be artefactually produced by off-axis flash photography in healthy eyes. The authors demonstrate the conditions needed to produce this phenomenon, which is more commonly seen in children due to their larger-sized pupils, photogenicity, and frequent off-axis shots.

Genotypic influences on severity of exudative age-related macular degeneration.

PURPOSE: Major genetic risk factors have recently been identified for age-related macular degeneration (AMD), including the ARMS2/LOC387715 and CFH at-risk polymorphisms. The study was conducted to establish correlations between the AMD genotype and both the phenotype and severity of AMD. METHODS: In a prospective cohort of 1216 AMD patients, four genotypic homozygous groups were identified (n = 264): double homozygous for wild-type alleles (group 1, n = 49), homozygous for the at-risk allele of ARMS2/LOC387715 only (group 2, n = 57), homozygous for the at-risk allele of CFH only (group 3, n = 106), and double homozygous for both at-risk alleles (group 4, n = 52). The phenotypic classification of exudative AMD was based on fluorescein angiography. RESULTS: Mean age at presentation was significantly lower in group 4 than in group 1 (P < 0.014). Patients in group 4 presented more often with bilateral CNV and fibrovascular scars than did patients in group 1 (P < 0.001 and < 0.0031 respectively) and with significantly lower visual acuity (VA) in the first affected eye than did patients in group 1 (P < 0.02). Patients in group 2 presented with worse VA than did patients in group 3 (P < 0.003). Classic CNV was more commonly associated with the at-risk allele of the ARMS2/LOC387715 locus than with the at-risk allele of the CFH gene (P < 0.026). CONCLUSIONS: This study demonstrates an association between the at-risk allele of the ARMS2/LOC387715 locus and classic CNV, fibrovascular lesions, and poor VA. Individuals double homozygous for both at-risk alleles had a higher risk of being affected with a severe form of AMD at an earlier age.