Ocular Complications in the Prone Position in the Critical Care Setting: The COVID-19 Pandemic.

PURPOSE: Ocular complications are common in the critical care setting but are frequently missed due to the focus on life-saving organ support. The SARS-CoV-2 (COVID-19) pandemic has led to a surge in critical care capacity and prone positioning practices which may increase the risk of ocular complications. This article aims to review all ocular complications associated with prone positioning, with a focus on challenges posed by COVID-19. MATERIALS AND METHODS: A literature review using keywords of "intensive care", "critical care", "eye care", "ocular disorders", "ophthalmic complications," "coronavirus", "COVID-19," "prone" and "proning" was performed using the electronic databases of PUBMED, EMBASE and CINAHL. RESULTS: The effects of prone positioning on improving respiratory outcomes in critically unwell patients are well established; however, there is a lack of literature regarding the effects of prone positioning on ocular complications in the critical care setting. Sight-threatening ophthalmic disorders potentiated by proning include ocular surface disease, acute angle closure, ischemic optic neuropathy, orbital compartment syndrome and vascular occlusions. CONCLUSIONS: COVID-19 patients may be more susceptible to ocular complications with increased proning practices and increasing demand on critical care staff. This review outlines these ocular complications with a focus on preventative and treatment measures to avoid devastating visual outcomes for the patient.

Pharmacotherapeutic management of atopic keratoconjunctivitis.

INTRODUCTION: Atopic keratoconjunctivitis (AKC) is a form of allergic eye disease that can have sight threating implications. Prevalence is underestimated due to scarce published data and treatment is expanding as a result of limitations of current strategies. This article aims to provide an up-to-date overview of AKC and summarize current and upcoming management. AREAS COVERED: The authors provide history, immunopathogenesis, and summary of the clinical manifestations of AKC as well as presenting a review of the evidence in relation to treatment options including mast cell stabilizers, antihistamines, corticosteroids, and immunomodulatory drugs based on clinical trials. Future trends, drug targets, and novel delivery drug systems are also highlighted in this review. EXPERT OPINION: Previously established treatment strategies of AKC had relied on corticosteroids, but the side effects of long-term therapy resulted in the expansion into the use of immunomodulatory drugs such as tacrolimus and ciclosporin. However, these too provide limited success due to the suboptimal structural properties of the current molecules. The ideal molecule should generate maximum permeability across the multi-layered structure of the cornea, be able to be formulated into eye drops for ease of application with minimal dosing and for maximal clinical effect.

Effect of varying skin surface electrode position on electroretinogram responses recorded using a handheld stimulating and recording system.

PURPOSE: A handheld device (the RETeval system, LKC Technologies) aims to increase the ease of electroretinogram (ERG) recording by using specially designed skin electrodes, rather than corneal electrodes. We explored effects of electrode position on response parameters recorded using this device. METHODS: Healthy adult twins were recruited from the TwinsUK cohort and underwent recording of light-adapted flicker ERGs (corresponding to international standard stimuli). In Group 1, skin electrodes were placed in a "comfortable" position, which was up to 20 mm below the lid margin. For subsequent participants (Group 2), the electrode was positioned 2 mm from the lid margin as recommended by the manufacturer. Amplitudes and peak times (averaged from both eyes) were compared between groups after age-matching and inclusion of only one twin per pair. Light-adapted flicker and flash ERGs were recorded for an additional 10 healthy subjects in two consecutive recording sessions: in the test eye, electrode position was varied from 2 to 10-20 mm below the lid margin between sessions; in the fellow (control) eye, the electrode was 2 mm below the lid margin throughout. Amplitudes and peak times (test eye normalised to control eye) were compared for the two sessions. RESULTS: Including one twin per pair, and age-matching yielded 28 individuals per group. Flicker ERG amplitudes were significantly lower for Group 1 than Group 2 participants (p = 0.0024). However, mean peak times did not differ between groups (p = 0.54). For the subjects in whom electrode position was changed between recording sessions, flash and flicker amplitudes were significantly lower when positioned further from the lid margin (p < 0.005), but peak times were similar (p > 0.5). CONCLUSIONS: Moving the skin electrodes further from the lid margin significantly reduces response amplitudes, highlighting the importance of consistent electrode positioning. However, this does not significantly affect peak times. Thus, it may be feasible to adopt a more comfortable position in participants who cannot tolerate the recommended position if analysis is restricted to peak time parameters.

The benefits of a peer-assisted mock PACES.

BACKGROUND: Peer-assisted learning (PAL) and mock examinations have been credited as effective teaching tools; however, there is a lack of research into their effectiveness in PACES (practical assessment of clinical examination skills). This study demonstrates an effective model and the benefits of PAL after its implementation in a mock PACES at Imperial College London. There is a lack of research into the effectiveness of PAL and mock examinations in PACES METHODS: A mock PACES was designed for fifth-year medical students. Examiners were recruited from the final year and from the foundation year doctor (intern) cohort. A Likert scale (1, strongly disagree; 5, strongly agree) questionnaire given before and after the exam was used to investigate its effectiveness. RESULTS: A total of 41 pre-mock exam surveys (57% completion rate) and 57 post-mock exam surveys (79% completion rate) were completed. Students felt significantly more confident after the mock PACES (mean 3.54 post-mock exam versus 2.68 pre-mock exam), with 90.64 per cent of students agreeing that this mock PACES was more useful than a lecture-based format, bedside teaching and small group teaching in order to prepare for this exam. Twenty-eight tutor surveys were completed (87.5% completion rate). Tutors agreed that the mock PACES had improved their confidence in their teaching ability (mean 4.07) and enhanced their clinical knowledge (mean 4.18). DISCUSSION: The mock PACES demonstrated benefits to confidence levels and knowledge both for tutees and tutors. The results demonstrate an effective model in examination preparation for PACES. This reinforces the holistic positive attributes gained from the use of PAL and mock examinations, whilst encouraging its use within the undergraduate syllabus.

Do twins share the same dress code? Quantifying relative genetic and environmental contributions to subjective perceptions of "the dress" in a classical twin study.

The phenomenon of contrasting color perceptions of "the dress" photograph has gained scientific interest. The mechanism underlying why individuals differ is yet to be fully explained. We use the powerful twin model design to ascertain the relative contribution of genetic and environmental factors on perception variation. A sample of 466 twins from the British TwinsUK registry were invited to report what color they saw in a standard image of the dress in standard illumination. The mean age of the participants was 49.5 (SD = 17.8) years, and 85% were female. When asked to choose between white and gold (WG) or blue and black (BB), 328 reported WG (70.4%) and 135 (29.0%) reported BB. Subjects choosing WG were significantly older (p < 0.01), but there was no significant difference in gender. Monozygotic (MZ) twins were more concordant in their responses than dizygotic (DZ) twins (0.46 vs. 0.36). Twin modeling revealed that genetic factors accounted for 34% (95% confidence interval, 5%-59%) of variation in the reported color of the dress when adjusted for age, whereas environmental factors contributed 66% (95% CI, 41%-95%). This study suggests environmental factors play a significant role in how an individual perceives the color of "the dress."