In vivo chromatic aberration in eyes implanted with intraocular lenses

Purpose. To measure in vivo and objectively the monochromatic aberrations at different wavelengths, and the chromatic difference of focus between green and infrared wavelengths in eyes implanted with two models of intraocular lenses (IOL).


Methods. Eighteen eyes participated in this study: nine implanted with Tecnis ZB99 1-Piece acrylic IOL and nine implanted with AcrySof SN60WF IOL. A custom-developed laser ray tracing (LRT) aberrometer was used to measure the optical aberrations, at 532 nm and 785 nm wavelengths. The monochromatic wave aberrations were described using a fifth-order Zernike polynomial expansion. The chromatic difference of focus was estimated as the difference between the equivalent spherical errors corresponding to each wavelength.


Results. Wave aberration measurements were highly reproducible. Except for the defocus term, no significant differences in high order aberrations (HOA) were found between wavelengths. The average chromatic difference of focus was 0.46 ± 0.15 diopters (D) in the Tecnis group, and 0.75 ± 0.12 D in the AcrySof group, and the difference was statistically significant (P < 0.05). Chromatic difference of focus in the AcrySof group was not statistically significantly different from the Longitudinal chromatic aberration (LCA) previously reported in a phakic population (0.78 ± 0.16 D). The impact of LCA on retinal image quality (measured in terms of Strehl ratio) was drastically reduced when considering HOA and astigmatism in comparison with a diffraction-limited eye, yielding the differences in retinal image quality between Tecnis and AcrySof IOLs not significant.


Conclusions. LRT aberrometry at different wavelengths is a reproducible technique to evaluate the chromatic difference of focus objectively in eyes implanted with IOLs. Replacement of the crystalline lens by the IOL did not increase chromatic difference of focus above that of phakic eyes in any of the groups. The AcrySof group showed chromatic difference of focus values very similar to physiological values in young eyes.

Mobile healthcare information systems : thru' the ant lens

Deployment of mobile technologies and applications in health care are becoming prevalent worldwide. As mobile innovation and standards in wireless continue to evolve, so does the mobile health care information systems framework. In this paper, we explore this evolving framework by synthesising current technologies, applications, issues and examining this through the actor-network theory (ANT) which seeks to understand socio-technical change by adopting a symmetric treatment of people and technologies.

Potential of telemedicine : a preliminary evaluation through the innovation diffusion lens

With the rapid diffusion of innovative technologies in the healthcare industry, the potential of telemedicine has increasingly come into focus. Touted as a catalyst for an equitable healthcare framework among nations, research is wide and one spotlight is on the potential of this innovation to diffuse among the wider society. In this paper, we attempt a preliminary evaluation of the potential of telemedicine through the components of [Diffusion of Innovations (4th ed.). NY: The Free Press] diffusion of innovations theoretical lens, drawing also as relevant from reported literature. We expect that this preliminary evaluation will facilitate further academic research and make other stakeholders, such as regulators, medical practitioners, telecommunication providers and vendors, aware of potential steps to be taken to leverage telemedicine diffusion.

A gaze through the lens of decision theory toward knowledge translation science

Research findings become evidence when an individual decides that the information is relevant and useful to a particular circumstance. Prior to that point, they are unrelated facts. For research translation to occur, research evidence needs filtering, interpretation, and application by individuals to the specific situation. For this reason, decision science is complementary to knowledge translation science. Both aim to support the individual in deciding the most appropriate action in a dynamic environment where there are masses of uncensored and nonprioritized information readily available. Decision science employs research theories to study the cognitive processes underpinning the filtering and integration of current scientific information into changing contexts. Two meta-theories, coherence and correspondence theories, have been used to provide alternative views and prompt significant debate to advance the science. The aim of this article is to stimulate debate about the relationship between decision theory and knowledge translation. Discussed is the critical role of cognition in clinical decision making, with a focus on knowledge translation. A critical commentary of the knowledge utilization modeling papers is presented from a decision science perspective. The article concludes with a discussion on the implications for knowledge translation when viewed through the lens of decision science.

Dietary omega 3 fatty acids decrease intraocular pressure with age by increasing Aqueous outflow

Purpose: To determine whether there is an association between dietary omega-3 (ω-3) fatty acid intake, age, and intraocular pressure (IOP) caused by altered aqueous outflow. Methods: Sprague–Dawley rats were fed either ω-3–sufficient (ω-3⁺) or ω-3–deficient (ω-3^–) diets from conception. The diets had 7% lipid content. The ω-3⁺ diet contained safflower, flaxseed, and tuna oils (5.5:1.0:0.5), and the ω-3^– diet contained safflower oil only. Intraocular pressure was measured at 5 to 40 weeks of age under light anesthesia (ω-3⁺, n = 39; ω-3^–, n = 48). Aqueous outflow was determined at 45 weeks in a subgroup of animals (ω-3⁺, n = 15;ω-3^–, n = 22) using pulsed infusion. Ciliary body tissues (n = 6 per group) were assayed for fatty acid content by thin-layer and gas-liquid chromatography in both diet groups. Results: Animals raised on ω-3⁺ diets had a 13% decrease in IOP at 40 weeks of age (13.48 ± 0.32 mm Hg vs. 15.46 ± 0.29 mm Hg; P < 0.01). When considered as a change in IOP relative to 5 weeks of age, the ω-3⁺ group showed a 23% decrease (P < 0.001). This lower IOP in the ω-3⁺ diet group was associated with a significant increase (+56%; P < 0.001) in outflow facility and a decrease in ocular rigidity (–59%; P < 0.001). The ω-3⁺ group showed a 3.3 times increase in ciliary body docosahexaenoic acid (P < 0.001). Conclusions: Increasing dietary ω-3 reduces IOP with age because of increased outflow facility, likely resulting from an increase in docosanoids. This indicates that dietary manipulation may provide a modifiable factor for IOP regulation. However, further studies are needed to consider whether this can modify the risk for glaucoma and can play a role in treatment of the disease.

Understanding informations systems outsourcing success and risks through the lens of cognitive biases

Because outsourcing of information systems (IS) is now widespread, it is generally assumed to be successful. It is also often assumed that outsourcing risks are easily managed. In this paper we adopt an “evidence based management” approach to first test these assumptions through a qualitative metaanalysis of academic studies into IS outsourcing outcomes. Our research reveals a shortage of reliable and valid evidence for outsourcing’s benefits, and for the level of risk involved. We then use data from a series of focus groups to explain the paradox of widespread adoption of a strategy with limited empirical support. These focus groups were interpreted through the lens of research on a
range of cognitive mechanisms and biases that are known to affect decision makers. We conclude that cognitive mechanisms that are likely to affect sourcing decisions include framing biases, cognitive dissonance, attribution error, and the “optimism”, “confirmation”, “disconfirmation” and “overconfidence” biases. Given the shortage of supporting evidence, and the potential for these biases to operate, we argue that researchers need to be more critical in their analysis of reports of the success and risks of IS outsourcing.

New lens: new vision

Interactive multimedia and the Internet challenge many aspects of teaching practice and assumptions. Catherine Beavis looks at a website that will support teachers and stimulate students.

Researching bullying with students : a lens on everyday life in an innovative school.

Bullying is a serious problem in schools. This paper reports on a project in which the authors worked with a group of secondary students in an innovative school in the north of England to research issues of bullying and safety. The student researchers used photographs to stimulate conversations with focus groups of their peers. The data showed that while there was little serious bullying in the school, there was an everyday practice of name-calling, isolation, and physical hassling associated with the formation and maintenance of a hierarchy of sub-cultural groupings in the school. The students’ research not only challenges the notion of bullying as necessarily involving a perpetrator and victim, but also offers a lens through which to examine the imbrication of educational differentiation via setting, testing and choice with youth identification practices. It is suggested that this project also has implications for the ways in which one understands and works for inclusion.

Exploring jockey and family life through a social health lens

Workplace practices form an overarching social determinant of health for Victorian jockeys and their families. This research highlights the importance of riding opportunity, coping with risk and danger, and the gratification associated with the lifestyle to be key characteristics that impact on jockey family health for the better or worse.

Through the lens of hetero-normative assumptions : re-thinking attitudes towards gay parenting

In this study we explored the attitudes and beliefs of nine heterosexual adults towards gay male and female couples parenting children. We conceptualised participants' perceptions as one primary lens through which gay parenting is viewed. Based on the narratives provided, this lens comprised hetero-normative, homophobic or heterosexist assumptions and coloured the way in which participants perceived aspects of the concept of gay couples parenting children. At times, participants attempted to adjust their primary lens and adopt different views that initially suggested ambivalence and sometimes contradictory positions. Despite the range of attitudes and assumptions about same-sex parenting, consensus over the potential negative developmental impact on children raised by same-sex parents remained evident. Evidence suggests that same-sex parenting is already a reality in Westernised nations and has little or no bearing on the sexual orientation of children. However, concern that children be brought up with every opportunity to 'become' heterosexual, whether they are the product of same-sex or opposite-sex parents, remains evident.