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PURPOSE:To determine the effects of optically imposed astigmatism on early eye growth in chicks. METHODS:5-day-old (P5) White Leghorn chicks were randomly assigned to either wear, monocularly, a "high magnitude" (H: +4.00DS/-8.00DC) crossed-cylindrical lens oriented at one of four axes (45, 90, 135, and 180; n = 20 in each group), or were left untreated (controls; n = 8). Two additional groups wore a "low magnitude" (L: +2.00DS/-4.00DC) cylindrical lens orientated at either axis 90 or 180 (n = 20 and n = 18, respectively). Refractions were measured at P5 and after 7 days of treatment for all chicks (P12), whereas videokeratography and ex-vivo eyeshape analysis were performed at P12 for a subset of chicks in each group (n = 8). RESULTS:Compared to controls, chicks in the treatment groups developed significant amounts of refractive astigmatism (controls: 0.03 ± 0.22DC; treatment groups: 1.34 ± 0.22DC to 5.51 ± 0.26DC, one-way ANOVAs, p ≤ 0.05) with axes compensatory to those imposed by the cylindrical lenses. H cylindrical lenses induced more refractive astigmatism than L lenses (H90 vs. L90: 5.51 ± 0.26D vs. 4.10 ± 0.16D; H180 vs. L180: 2.84 ± 0.44D vs. 1.34 ± 0.22D, unpaired two-sample t-tests, both p ≤ 0.01); and imposing with-the-rule (H90 and L90) and against-the-rule astigmatisms (H180 and L180) resulted in, respectively, steeper and flatter corneal shape. Both corneal and internal astigmatisms were moderately to strongly correlated with refractive astigmatisms (Pearson's r: +0.61 to +0.94, all p ≤ 0.001). In addition, the characteristics of astigmatism were significantly correlated with multiple eyeshape parameters at the posterior segments (Pearson's r: -0.27 to +0.45, all p ≤ 0.05). CONCLUSIONS:Chicks showed compensatory ocular changes in response to the astigmatic magnitudes imposed in this study. The correlations of changes in refractive, corneal, and posterior eyeshape indicate the involvement of anterior and posterior ocular segments during the development of astigmatism.

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Purpose: To determine the effects of optically imposed astigmatism on early eye growth in chicks. Methods: 5-day-old (P5) White Leghorn chicks were randomly assigned to either wear, monocularly, a “high magnitude” (H: +4.00DS/-8.00DC) crossed-cylindrical lens oriented at one of four axes (45, 90, 135, and 180; n = 20 in each group), or were left untreated (controls; n = 8). Two additional groups wore a “low magnitude” (L: +2.00DS/−4.00DC) cylindrical lens orientated at either axis 90 or 180 (n = 20 and n = 18, respectively). Refractions were measured at P5 and after 7 days of treatment for all chicks (P12), whereas videokeratography and ex-vivo eyeshape analysis were performed at P12 for a subset of chicks in each group (n = 8). Results: Compared to controls, chicks in the treatment groups developed significant amounts of refractive astigmatism (controls: 0.03±0.22DC; treatment groups: 1.34±0.22DC to 5.51±0.26DC, one-way ANOVAs, p≤0.05) with axes compensatory to those imposed by the cylindrical lenses. H cylindrical lenses induced more refractive astigmatism than L lenses (H90 vs. L90: 5.51±0.26D vs. 4.10±0.16D; H180 vs. L180: 2.84±0.44D vs. 1.34±0.22D, unpaired two-sample t-tests, both p≤0.01); and imposing with-the-rule (H90 and L90) and against-the-rule astigmatisms (H180 and L180) resulted in, respectively, steeper and flatter corneal shape. Both corneal and internal astigmatisms were moderately to strongly correlated with refractive astigmatisms (Pearson’s r: +0.61 to +0.94, all p≤0.001). In addition, the characteristics of astigmatism were significantly correlated with multiple eyeshape parameters at the posterior segments (Pearson’s r: -0.27 to +0.45, all p≤0.05). Conclusions: Chicks showed compensatory ocular changes in response to the astigmatic magnitudes imposed in this study. The correlations of changes in refractive, corneal, and posterior eyeshape indicate the involvement of anterior and posterior ocular segments during the development of astigmatism. [ABSTRACT FROM AUTHOR]

Canadian subspecialty residency training programs are developed around the learning objectives listed in the seven Canadian Medical Education Directives for Specialists (CanMEDS) criteria. Delivering content on objectives outside of those traditionally acquired in clinical rotations can be a challenge. In the present article, the planning process, curriculum development, and evaluation and assessment of a national subspecialty conference model in providing CanMEDS objective-based content sessions in the categories other than Medical Expert (Professional, Scholar, Communicator, Collaborator, Manager and Health Advocate) is described. It is hypothesized that the development of a CanMEDS objective-based curriculum would be positively received by subspecialty residents attending this conference. Attendees of sessions in a two-year curriculum cycle assessed the content as valuable, relevant and effective. The application of this process can be useful to other subspecialty residency training programs to meet the needs of their CanMEDS objective-based training requirements. [ABSTRACT FROM AUTHOR]

Abstract: Background: Patient safety is of great importance in the pediatric emergency department (PED). The combination of acutely and critically ill patients and high patient volumes creates a need for systems to support physicians in making accurate and timely diagnoses. Electronic patient tracking systems can potentially improve PED safety by reducing overcrowding and enhancing security. Objectives: To enhance our understanding of current electronic tracking technologies, how they are implemented in a clinical setting, and resulting effect on patient care outcomes including patient safety. Methods: Nine databases were searched. Two independent reviewers identified articles that contained reference to patient tracking technologies in pediatrics or emergency medicine. Quantitative studies were assessed independently for methodological strength by two reviewers using an external assessment tool. Results: Of 2292 initial articles, 22 were deemed relevant. Seventeen were qualitative, and the remaining five quantitative articles were assessed as being methodologically weak. Existing patient tracking systems in the ED included: infant monitoring/abduction prevention; barcode identification; radiofrequency identification (RFID)- or infrared (IR)-based patient tracking. Twenty articles supported the use of tracking technology to enhance patient safety or improve efficiency. One article failed to support the use of IR patient sensors due to study design flaws. Conclusions: Support exists for the use of barcode-, IR-, and RFID-based patient tracking systems to improve ED patient safety and efficiency. A lack of methodologically strong studies indicates a need for further evidence-based support for the implementation of patient tracking technology in a clinical or research setting. [Copyright &y& Elsevier]