Rapid, objective detection of cataract-induced blur using a bull's eye photodetector.

PURPOSE: To determine whether optical aberrations caused by cataract can be detected and quantified objectively using a newly described focus detection system (FDS). SETTING: The Wilmer Opthalmological Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. METHODS: The FDS uses a bull's eye photodetector to measure the double-pass blur produced from a point source of light. To determine the range and level of focus, signals are measured with a series of trial lenses in the light path selected to span the point of best focus to generate focus curves. The best corrected visual acuity (BCVA), refractive error, lens photograph grades, and FDS signals were obtained in 18 patients scheduled to have cataract surgery. The tests were repeated 6 weeks after surgery. RESULTS: The mean FDS outcome measures improved after cataract surgery, with increased peak height (P=.001) and decreased peak width (P=.001). Improvement in signal strength (integral of signal within +/-1.5 diopters of the point of best focus) strongly correlated with improvement in peak height (R(2)=.88, P<.0001) and photographic cataract grade (R(2)=.72, P<.0001). The mean BCVA improved from 20/50 to 20/26 (P<.0001). The improvement in BCVA correlated more closely with FDS signal strength (R(2)=.44, P=.001) than with cataract grade (R(2)=.25, P=.06). CONCLUSIONS: Improvement in FDS outcome measures correlated with cataract severity and improvement in visual acuity. This objective approach may be useful in long-term studies of cataract progression.

Interpretations of national identity in post-conflict Northern Ireland: A comparison of different school settings

It is generally accepted that education has a significant role to play in anysociety transitioning from conflict to a more peaceful dispensation. Indeed,some have argued that the education system potentially represents the singlemost effective agent of social change with the capacity to bridge ethnicdivision in conflict affected countries. Despite the potential, educationalpolicy-makers grapple with the dilemma as to precisely how school systemscan best facilitate this agenda. This paper thus attempts to shed lightupon the dilemma by exploring pupil identity and associated intergroupattitudes across various school types in Northern Ireland. Five schools wereselected for the study with each one representing a particular sector withinthe Northern Irish education system (maintained grammar, maintainedsecondary, controlled grammar, controlled secondary, integrated). This led toa total sample size of 265 pupils. The main findings show that children acrossseparate Catholic, separate Protestant and mixed Catholic and Protestanteducational contexts construct and interpret identity differently. At thesame time, our data suggest that no one school setting has supremacy inpromoting social cohesion. The implications of these findings are discussed.