PURPOSE. Few studies have assessed optic disk and retinal morphology in infants. Here the optic disk and optic disk-to-fovea distance were measured in preterm and full-term infants in vivo. METHODS. Optic disk (OD) dimensions and the center-to-center distance between the OD and the macula were measured using digital imaging in infants undergoing routine ophthalmic examinations. Postmenstrual age of the mother at the time of examination ranged from 32 to 50 weeks. From each image, the OD-to-fovea distance (ODF) and the OD height (ODH) and OD width (ODW) were measured. RESULTS. In 51 retinal images from 51 infants, mean Ϯ SD values obtained were 4.4 Ϯ 0.4 mm (ODF), 1.41 Ϯ 0.1 9 mm (ODH), and 1.05 Ϯ 0.13 mm (ODW). These dimensions did not change significantly over the age range studied. The mean value for the ratio between ODF and mean OD diameter (ODF/DD) was 3.76. CONCLUSIONS. Results of this in vivo study suggest that though the optic nerve head diameter increases by more than 50%, only limited growth occurs at the highly organized area of the posterior pole from birth to adulthood. This study discusses the finding of a large-angle kappa in infants and the use of a disk macula/disk diameter ratio in the diagnosis of optic nerve hypoplasia.

IntroductionThe objective of the study was to determine the relative importance (RI) of treatment attributes psoriasis patients and physicians consider when choosing between biologic therapies based on psoriasis severity.MethodsA discrete choice experiment (DCE) weighting preference for eight sets of hypothetical treatments for moderate or severe psoriasis was conducted. DCE hypothetical treatments were defined and varied on combinations of efficacy, safety, and dosing attributes [frequency/setting/route of administration (ROA)].ResultsWhen assuming moderate psoriasis in the patient DCE, ROA (RI 29%) and efficacy (RI 27%) drive treatment choices. When assuming severe disease in the DCE, patients preferred treatments with higher efficacy (RI 36%); ROA was relatively less important (RI 15%). From the physician perspective, ROA (RI 32%) and efficacy (RI 26%) were most important for moderate psoriasis patients. In the physician model for severe psoriasis, efficacy (RI 42%) was the predominant driver followed by ROA (RI 22%). Regardless of severity, probability of loss of response within 1 year was the least important factor.ConclusionsThe severity of disease is a critical element in psoriasis treatment selection. There are high levels of alignment between physician- and patient-derived preferences in biologic treatment choice selection for psoriasis.FundingJanssen Pharmaceuticals.

Amphibians, the most threatened group of vertebrates, are seen as indicators of the sixth mass extinction on earth. Thousands of species are threatened with extinction and many have been affected by an emerging infectious disease, chytridiomycosis, caused by the fungal pathogen, Batrachochytrium dendrobatidis (Bd). However, amphibians exhibit different responses to the pathogen, such as survival and population persistence with infection, or mortality of individuals and complete population collapse after pathogen invasion. Multiple factors can affect host pathogen dynamics, yet few studies have provided a temporal view that encompasses both the epizootic phase (i.e. pathogen invasion and host collapse), and the transition to a more stable co-existence (i.e. recovery of infected host populations). In the Sierra Nevada mountains of California, USA, conspecific populations of frogs currently exhibit dramatically different host/ Bd-pathogen dynamics. To provide a temporal context by which present day dynamics may be better understood, we use a Bd qPCR assay to test 1165 amphibian specimens collected between 1900 and 2005. Our historical analyses reveal a pattern of pathogen invasion and eventual spread across the Sierra Nevada over the last century. Although we found a small number of Bd-infections prior to 1970, these showed no sign of spread or increase in infection prevalence over multiple decades. After the late 1970s, when mass die offs were first noted, our data show Bd as much more prevalent and more spatially spread out, suggesting epizootic spread. However, across the ~400km2 area, we found no evidence of a wave-like pattern, but instead discovered multiple, nearly-simultaneous invasions within regions. We found that Bd invaded and spread in the central Sierra Nevada (Yosemite National Park area) about four decades before it invaded and spread in the southern Sierra Nevada (Sequoia and Kings Canyon National Parks area), and suggest that the temporal pattern of pathogen invasion may help explain divergent contemporary host pathogen dynamics.

Background Provision of relevant pre-learning materials has been shown to increase student engagement and improve outcomes in medical education. This non-randomised study attempts to quantify the educational gains, and relative efficacy of video and written pre-learning materials, in ophthalmology undergraduate teaching.Methods 98 final year medical students were contacted prior to their three-day ophthalmology placements at a British tertiary ophthalmology unit. All participants were sent welcome packs prior to arrival requesting they undertake 90 minutes of work focusing on a list of specified ophthalmic conditions. In addition one cohort ( N =33) were sent written materials and another ( N =32) were provided with video materials. The teaching remained otherwise unchanged. On arrival participants completed a simple knowledge test, a questionnaire estimating the time they spent preparing for the placement and a self-reported knowledge score. At the conclusion of each placement participants completed a challenging knowledge test, a clinical skills test and repeated self-reported knowledge scores.Results 86.7% of students receiving specified materials claimed to complete pre-placement work compared to 69.7% of those receiving learning outcomes alone ( p =0.05). Students receiving learning materials scored higher in tests of knowledge ( p <0.001), 74.8% (72.4-77.2%) vs 63.6% (95%CI 59.3-67.9%) and skills ( p =0.04), 86.9% (83.9-89.9%) vs 81.3% (77.2-85.4%). Students using video resources outperformed students using written materials in their visual acuity assessment test ( p =0.03), 90.4% (86.6-94.2%) vs 83.6% (80.1-87.1%) whilst those receiving written rather than video material performed better in the end of placement knowledge test ( p =0.03), 72.0% (68.9%-75.1%) vs 77.7% (74.3-81.1%).Conclusion This study showed that providing pre-placement learning materials improves undergraduates’ commitment and achievement. Written materials better facilitate knowledge acquisition while video materials preferentially promote skill acquisition. This is a novel demonstration within ophthalmology and can help address the imbalance between the expectations placed on graduates and the resources committed to ensuring they are met.

Background: Provision of relevant pre-learning materials has been shown to increase student engagement and improve outcomes in medical education. This non-randomised study attempts to quantify the educational gains, and relative efficacy of video and written pre-learning materials, in ophthalmology undergraduate teaching. Methods: Ninety-eight final year medical students were contacted prior to their three-day ophthalmology placements at a British tertiary ophthalmology unit. All participants were sent welcome packs prior to arrival requesting they undertake 90 min of work focusing on a list of specified ophthalmic conditions. One cohort (N = 33) were sent written materials, another (N = 32) was provided with video materials and a third cohort (N = 33) were not sent any materials. On arrival participants completed a simple knowledge test, a questionnaire estimating the time they spent preparing for the placement and a selfreported knowledge score. The teaching on placement was the same for all cohorts. At the conclusion of each placement participants completed a challenging knowledge test, a clinical skills test and repeated self-reported knowledge scores. Results: Eighty seven percent of students receiving specified materials claimed to complete pre-placement work compared to 70% of those receiving learning outcomes alone (p = 0.05). Students receiving learning materials scored higher in the post-placement tests of knowledge (p < 0.001), 74.8% (72.4-77.2%) vs 63.6% (95%CI 59.3-67.9%) and skills (p = 0.04), 86.9% (83.9-89.9%) vs 81.3% (77.2-85.4%). Students using video resources outperformed students using written materials in their visual acuity assessment test (p = 0.03), 90.4% (86.6-94.2%) vs 83.6% (80.1-87.1%) whilst those receiving written rather than video material performed better in the end of placement knowledge test (p = 0.03), 77.7% (74.3-81.1%) vs 72.0% (68.9-75.1%). Conclusion: This study showed that providing pre-placement learning materials improves undergraduates' commitment and achievement. Written materials better facilitate knowledge acquisition while video materials preferentially promote skill acquisition. This is a novel demonstration within ophthalmology and can help address the imbalance between the expectations placed on undergraduates and the resources committed to ensuring they are met.