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EW MEETING REPORTER 58 World Glaucoma Congress August 2011 who were not medically treated and did not develop a primary open- angle glaucoma endpoint or have narrow anterior chamber angles. After cataract surgery, the mean IOP dropped 4.3 mm Hg from 23.9 mm Hg to a post-op value of 19.6 mm Hg (p<0.001). For the fellow eye without cataract extraction, the cor- responding drop was only 0.4 mm Hg (from 23.6 to 23.2). The effect was sustained for 30 months. Regional initiatives in glaucoma Ananth Viswanathan, M.D., con- sultant surgeon, Moorfields Eye Hospital, London, described the European Glaucoma Society's GlaucoGene project as one of several large-scale genome-wide association studies looking for genetic markers for glaucoma. The GlaucoGene proj- ect recently reported two genes, one each on chromosomes 1 and 9, that together confer a relative risk of 4.5; that is, individuals with these genes have a 4.5-fold higher risk for glau- coma than individuals without these genes. The horizon for glaucoma ge- netics research includes looking not at DNA sequences but all the way down to individual base pairs, and also epigenetics, which evaluates ways in which the environment reg- ulates gene expression. Marc Schargus, M.D., University Eye Hospital Würzburg, Germany, reported that there are 8.5 million Europeans with glaucoma, 10% of whom have complicated glaucoma. Often when referred for subspecialty glaucoma care, these patients present with no medical records. He described the Glauco- Card, an electronic medical record that would store key glaucoma-re- lated parameters on individuals to facilitate co-management of glau- coma patients. Features of the pro- posed GlaucoCard would include import/export functionality to make sharing of medical records between clinicians straightforward. John Thygesen, M.D., Copen- hagen University, Denmark, dis- cussed the importance of strong liaisons with glaucoma patient asso- ciations. The World Glaucoma Asso- ciation (which hosts the World Glaucoma Congress) established a committee in 2004 to improve rela- tions with patient associations worldwide. In fact, there is a parent association that links many global glaucoma patient groups under a single umbrella: the World Glaucoma Patient Association (www.wgpa.org). One product of the liaison between the WGA and the WGPA is World Glaucoma Day, which debuted in 2008 and has now expanded to become World Glaucoma Week each March. The pressures of glaucoma Robert N. Weinreb, M.D., ophthal- mology chair, University of Califor- nia, San Diego, reported that IOP is highest at night when measured in the habitual position (sitting during waking hours, supine at night). "If you only measure IOP during office hours, you will miss peak IOP at least two-thirds of the time," he said. Potential ways to address this clinical dilemma include home tonometry as well as continuous IOP monitoring. Neither is clinically use- ful at the present time owing to technical limitations. Kuldev Singh, M.D., M.P.H., Stanford University, Palo Alto, Calif., discussed the roles of IOP fluctua- tions and ocular perfusion pressure as emerging risk factors for glau- coma. Data from major clinical trials on IOP fluctuation are mixed. "We don't have conclusive evidence that fluctuation of IOP is an independent risk factor for glaucoma progres- sion," he said. But regarding ocular perfusion pressure, which is blood pressure minus IOP, he said, "there is very strong evidence that low IOP increases both the risk of glaucoma and its progression." Keith Martin, M.D., University of Cambridge, England, pointed out that while we focus much of our attention on IOP, which is a transcorneal pressure differential, glaucoma damage happens in the back of the eye, at the level of the optic nerve. He suggested that translaminar pressure (which can be approximated as IOP minus cere- brospinal fluid pressure [CSF]) may be a more useful parameter to help understand glaucomatous optic nerve damage and disease progres- sion. "There is emerging evidence that the IOP-CSF pressure difference correlates better with visual field and optic nerve parameters than IOP alone," he said. Jeff Liebmann, M.D., New York, discussed IOP-independent factors that might play a role in the development and progression of glaucoma. These include ocular bio- mechanics of the optic nerve head, genetic factors, aging, and other processes such as disc hemorrhage and peripapillary atrophy that all Reporting live from the 2011 World Glaucoma Congress, Paris World continued from page 57

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