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Highlights of the World Glaucoma Congress

July 8-11, Boston, MA, USA

Subhabrata Chakrabarti, Hyderabad, India

The third World Glaucoma Congress held at Boston from July 8-11, 2009, was indeed a feast of knowledge for clinicians and basic science researchers. I was more interested in studies that advanced our understanding of the underlying molecular mechanisms in glaucoma development, its relation to structural defects and corresponding functional implications. Thus, my inclination was towards newer ideas (D07) that dealt with retinal ganglion cell damage that were further substantiated by in vitro studies and animal models. The plenary lunch symposium (PLS) on IOP provided newer insights into the mechanisms of neuronal degeneration and neuroprotection in glaucoma. While IOP continued to be a risk factor for glaucoma progression, its role in influencing neuronal dysfunction leading to RGC damage would be a challenging area of research in the near future. Supplementing these symposia, were two courses on experimental models in glaucoma (C25) and neuroprotection and apoptosis (C29) that provided extensive insights into the underlying mechanism of RGC loss and some perspectives on treatment options.

The clinician scientist symposium (D15) also addressed some issues pertaining to molecular mechanisms of IOP regulation and mitochondrial dysfunctions. There was an overview on gene-based therapies that may have relevance to glaucoma in the future. Continuing with therapies, the session on innovative approaches for protecting RGCs (S10) proposed alternatives for the prevention of elevated IOP and axonal degeneration through potential cell-based therapies, including stem cell therapies. Similarly, the basics of uveoscleral mechanisms in humans and animals, along with their therapeutic potential, provided another important dimension in understanding IOP regulation (D17). The other highlights were the global assembly that provided important updates on WGA activities and the inaugural session with special lectures by experts outside the glaucoma community. Overall, the WGC is an educative forum that helps in admixture of novel ideas in understanding glaucoma biology, and fosters networking and collaboration between colleagues worldwide.

Tanuj Dada, New Delhi, India

The World Glaucoma Congress held at Boston in July, was a truly unique scientific forum cutting across all geo-political boundaries and uniting the global glaucoma community as one family for an enriching experience which will be cherished for a long time. The highlights of the congress included the presentation of an update on the consensus reports, under the chairmanship of Prof. Weinreb, which detailed the current thinking in glaucoma regarding population screening, measurement of ocular blood flow, investigations for structure and function, IOP and surgery. This was very informative for the participants as it gave preferred practice patterns and key take-home messages which could be practically applied in clinical practice. The grand rounds with clinical case presentations were thought provoking and generated immense clinical interest among the audience. I found the instruction course on Glaucoma biostatistics to be very useful for planning research work, writing a scientific paper, and the critical evaluation of studies published in literature, especially the selection and application of statistical tests for the reliability of new technology, and the reporting of surgical success by WJ Feuer. The session on changing trends in the surgical management of PACG chaired by Prof. Lam provided new insights into a variety of surgical options now available for managing angle closure, including corneal indentation and AC paracentesis for an acute attack and goniosynechiolysis and lens extraction for PACG. Finally, the video sessions on glaucoma and combined surgery on the final day of the congress were spectacular, showcasing a variety of microsurgical techniques such as the safe surgery system for trabeculectomy, suprachoroidal and trabecular implants, canaloplasty, and phaco in complicated situations such as pseudoexfoliation and PACG. Not to forget the wonderful banquet at the Boston Public Library with the memorable karaoke by the 'tenors' of the WGA which 'rocked' the congress participants.

Mingguang He, Guangzhou, PR China

• A population-based survey in Korea reported the prevalence of primary angle closure suspect, primary angle closure, and primary angle closure glaucoma as being 2.1%, 0.5% and 0.5%, respectively. These reported rates are much lower than those observed in the Chinese population. Further work is needed to clarify whether this is due to methodology, environment or genetic background. (J.H. Lee et al.)
• Cerebrospinal fluid pressure was lower in POAG cases with normal IOP and in normal controls compared to POAG with elevated IOP. All subjects were enrolled prospectively. This study suggests that the translamina cibrosa pressure is a risk factor for POAG. (R. Ren et al.).
• Thirty percent of relatives of primary angle closure patients had clinically significant angle closure. This study was conducted in white British families. It offers a unique opportunity to study the mechanism (anatomical features and genetic basis) of angle closure in European people compared to East Asians. (S. Low et al.).
• A novel automated alternation flicker technology offers a straightforward approach to the detection of progressive glaucomatous neuropathy. The efficacy is as good as the stereophoto method. (M. Radcliffe et al.).
• Using a case control design, this study identified a novel SNP variance as a strong promoter for the CYP1B1 gene in primary congenital glaucoma in Indian subjects. (S. Chakrabarti et al.).
• The video session on July 11 was particularly informative for glaucoma clinicians and new techniques, such as new microshunts, trabectomy, goniosynechiaelysis were demonstrated.

Megumi Honjo, Tokyo, Japan

The Didactic sessions on angle-closure glaucoma (ACG) were quite informative. The management of ACG, including diagnosis, classification and treatments, is a really important issue for discussion. In Didactic Session 01, the novel functional and structural measures for the diagnosis and classification of ACG were presented, and we could reconfirm our knowledge and consensus when the session was over. The explanation of classification, which is supported by ultrasound biomicroscopy imaging, was quite helpful for understanding the precise structure of the anterior segment of the eye thoroughly. In Didactic Session 10, the practical way to treat patients with ACG was discussed. Starting from laser peripheral iridotomy, which used to be the gold standard for the treatment of acute angle closure to reduce IOP, several approaches were introduced, including argon laser peripheral iridoplasty, anterior chamber paracentesis, corneal indentation, filtration surgery, goniosynechalysis, and cataract extraction. From the session, we could learn that each treatment has both advantages and disadvantages. Among these treatments, goniosynechalysis combined with cataract extraction seemed to be attractive as a safe and effective procedure. At the end of the session, the chair asked whether the session had had any effect on changing the attitude toward the treatment of ACG. It was impressive to see that half the audience raised their hands after the session when the chair asked if they would consider goniosynechialysis as a choice of treatment for ACG, even though only a quarter of the audience had had any experience with the procedure.

Kenji Kashiwagi, Yamanashi, Japan

Swine flu concerns prevented me from attending the ARVO meeting, and so the WGA meeting was the first large international meeting for me in 2009. I would like to mention various topics covered at this year's meeting:

A. Glaucoma medication
Anti-glaucoma medication has changed dramatically over the past ten years. We can now reduce pressure more powerfully than before. It was particularly striking to hear a number of papers that emphasized that attention should be paid to medication-related adverse effects and keeping good adherence. For many glaucoma patients, this must surely be as important as requiring much lower pressure. Many papers focused on anti-glaucoma medication-related adverse effects and some reported how we can keep good adherence of glaucoma treatment.

B. Objective and quantitative evaluation
Some parameters, such as visual field test, optic nerve head evaluation, and angle evaluation, are subjective, and this makes the consistency of follow up of glaucoma treatment difficult. Development of various instruments, especially optical coherent tomography (OCT), enables objective and quantitative evaluation both in the posterior and anterior segments. Some papers reporting availability of OCT in glaucoma assured me that ophthalmologists, including non-glaucoma specialists, can treat and follow up patients with glaucoma more precisely than before by employing these new instruments.

C. New glaucoma therapy
Although some papers reported the usefulness of new anti-glaucoma therapy, their data did not provide solid evidence and they were not fully supported as a new treatment for glaucoma. It still is too premature to consider new glaucoma therapy in clinical practice. But, I really do believe that there is a need to develop a pressure- independent therapy.

D. Miscellaneous
I was very impressed that so many people got together to listen to and discuss the oral presentations. But very few people visited the poster area throughout the meeting and the number of no-show posters was considerable. There were many nice posters in the poster session. It is unfortunate that many attendees missed checking these posters and discussing them with their authors, and we need to consider how to improve this point at forthcoming meetings.
This first visit to Boston provided me with unforgettable memories. On my way there, a heavy thunderstorm delayed me at JFK airport for eight hours. The traditional and beautiful cityscape gave me much pleasure. But best of all was getting new ideas and communicating with old and new friends. I look forward to seeing them all again at the 2011 WGC.

Christopher Leung, Hong Kong, PR China

Understanding the mechanism of retinal ganglion cell (RGC) degeneration in glaucoma is fundamental in devising effective neuroprotective treatment. A number of lectures at the World Glaucoma Congress this year highlighted the concept of compartmentalized degeneration in glaucoma (Compartmentalized RGC damage by Simon John; Neuronal mechanism of glaucomatous disease and Molecular/gene therapies by Keith Martin). While the molecular pathways leading to axonal destruction and RGC death remain to be established, there is mounting evidence suggesting that the mechanism of axonal degeneration is distinct from the process of RGC apoptosis. An early piece of evidence comes from Libby et al. and shows that the inactivation of Bax protected RGC somata, but not their axons, in the DBA2J mouse model (Libby et al. PLoS Genet. 2005;1:17-26). A follow-up study by the same group demonstrated the preservation of axons and function of RGCs (measured by PERG) in DBA2J mice by introducing the expression of Wlds, a know gene conferring protection against axonal degeneration (Howell GR, et al. J Cell Biol. 2007;179:1523-37). These findings are in line with the results from other experimental models of neurodegenerative diseases in the central nervous system. The concept of compartmentalized RGC damage underscores the fact that protecting RGCs alone may not be sufficient in preventing axonal degeneration and functional impairment in glaucoma. While delivery of neurotrophic factors could delay loss of RGCs, they may not rescue or reverse axonal self-destruction. In order to preserve the functional integrity of RGCs, neuroprotective strategies should be targeted on the cell bodies as well as on the axonal and dendritic structures. Understanding the molecular mechanisms triggering axonal degeneration in glaucoma is an important area for more research.

Tarek Shaarawy, Geneva, Switzerland

The highlight of the WGC for me was the keynote lecture of Prof Robert S. Langer. Prof Langer is the David H. Koch Institute Professor (there are 14 Institute Professors at MIT; being an Institute Professor is the highest honor that can be awarded to a faculty member). Dr. Langer has written approximately 1,050 articles. He also has approximately 750 issued and pending patents worldwide. Dr. Langer's patents have been licensed or sublicensed to over 220 pharmaceutical, chemical, biotechnology and medical-device companies. By choosing the most cited engineer in history to give a keynote lecture, the WGC offered its participants a real treat. Listening to Prof Langer, and knowing how many lives have been touched by his genius work put most of the attendees in total awe. It reminded us of the fact that there is a lot of innovative engineering in modern medicine, and once more stressed the importance of us, clinicians, searching beyond our natural borders to reach out to colleagues and fellow scientists in different branches of science. Such collaboration is definitely the key to any future breakthroughs in glaucoma. On a more personal note, I have to confess that listening to Robert Langer from a seat close to the podium, I could not help but wonder if he, or others of the same caliber, have somewhere in their file cabinets the much sought after step-forward in our field. It is up to the WGA, with the massive cumulative intellectual capacity of its committee members, to get such beautiful minds interested in our field.

Arthur Sit, Rochester, MN, USA

The World Glaucoma Congress (WGC) was held in Boston, MA, from July 8-11, 2009. It is impossible to fully cover the scope of activities of the WGC and this report only provides my individual impressions of a few of the scientific sessions and events.

The WGC started with symposia organized by 12 individual glaucoma societies. These included primarily symposia from national societies, but also the Optometric Glaucoma Society Symposium which provided 'A New Look at IOP and Tonometry,' focusing on the role of IOP fluctuations in glaucoma. IOP measurement is central to our daily clinical practice, and I found this update on the emerging technologies for IOP measurement illuminating. The host organization followed with the 'Best of the American Glaucoma Society Symposium', providing an excellent sample of research from AGS members. The symposium illustrated the central role that AGS members play in advancing glaucoma research.

The highlights of the opening day undoubtedly were the keynote lectures by Prof. Robert S. Langer (Institute Professor at the Massachusetts Institute of Technology; recipient of the 2006 US National Medal of Science) and Prof. Robert C. Merton (John and Natty McArthur University Professor at the Harvard Business School; recipient of the 1997 Nobel Prize in Economic Sciences). Prof. Langer disc ussed his pioneering work in biomedical engineering, while Prof. Merton discussed the importance of risk assessment in modern financial systems. The application of engineering to glaucoma has been a focus of my own research, and while the keynote lectures did not directly relate to glaucoma, they highlighted the value of applying mathematical and engineering rigor to other fields.

The next three days of the meeting presented the challenge of choosing from among 11 Symposia, 22 Didactic sessions, and 39 Courses. The Translational Science session focused on the multiple aspects of laboratory research and how it may translate to clinical practice. This ranged from fundamental research in genetics and pathology to near-clinical measurements of retinal ganglion cell function and aqueous humor dynamics. Ultimately all glaucoma research has the purpose of helping patients. I particularly enjoyed this session for providing a view from different types of basic research that all had clear potential for improving patient care. The Free Paper sessions in Clinical and Basic science included 30 papers selected for special interest by the Program Committee from over 700 submitted abstracts. These papers included a broad range of topics and represented countries from around the world. I found these sessions very enlightening as they illustrated the fact that high quality glaucoma research is being performed around the world. The Emerging Surgery Session provided updates on the latest work to improve the options for glaucoma surgery. This included updates of filtering surgery, non-penetrating surgery and angle surgery. Glaucoma surgery is an area that appears to be changing rapidly and I enjoyed the updates of the latest technologies and techniques. The Uveoscleral Outflow session provided an overview of this increasingly important but poorly understood outflow route. Although the uveoscleral outflow route has been recognized for decades, the difficulty in directly measuring flow through this route means that we are always learning more. Although I was involved with this session, I nevertheless found it to be very educational.

Of course the WGC would not be complete without its social activities. In particular, the Gala Evening at the Boston Public Library was a stunning success. I found the opportunity to socialize with colleagues from around the world in a magnificent setting to be one of the truly extraordinary aspects of the WGC. Now that the meeting has finished, memories of the social events of the WGC will undoubtedly be some of the most enduring from the four special days in Boston. I look forward to the next WGC in 2011.

Tina Wong, Singapore

The highlight of the meeting for me fell on the third day, which started with a debate on the initial treatment for glaucoma: medical versus laser versus surgery. The current President Remo Susanna Jr opened the session. The panel of international speakers delivered their reasons for each management type to the audience. Firstly, Dr Goni revealed that since the era of prostaglandins there is as yet no randomized clinical trial evaluating these three treatment modalities we have to treat our patients. With the advent of prostaglandin analogues and fixed combinations, Dr Grigera stated that medical treatment is an effective and widely accepted first line treatment option, whereas Dr Realini shared with us how lasers are considerably cheaper but with comparable IOP lowering to medical therapy. With laser therapy, no uninvited ocular side effects would be encountered, some of which can lead to an adverse effect on filtration surgery outcome, if necessary in the future. Laser therapy is also repeatable. Dr Skuta argued that surgery was considered an attractive initial treatment especially in advanced disease, based on evidence from the AGIS and CITGS, which showed that an IOP of less than 14 mmHg significantly delayed visual field progression and that, in CITGS, visual field progression was more stable in the surgically- versus the medically-treated group. Dr Fechtner wrapped up the session by putting a real life perspective on the choice of treatment for patient,s which always boils down to cost effectiveness. The Hot Topics in glaucoma care included presentations on the significance of ocular surface disease (OSD) in the glaucoma patient. Too often this is a difficult and chronic condition to treat, but is more common in glaucoma patients than realized. This is especially so with the introduction of more effective IOP lowering medication, which means that patients will be using eye drops for much longer than in the past before requiring surgery. Dr Fechtner shared with us that the greater the number of bottles of medication the patient uses, the higher incidence of OSD. Furthermore, 60% of glaucoma patients use lubricants, which is a telling sign. Dr Baudoin discussed the possibility of distinguishing dryness from blindness in our patients who may have unrecognized or untreated OSD. Finally, Dr Kahook shared with us the improved clinical signs of OSD with the use of a new preservative than with the current benzalkonium chloride.

The overall feeling I had from this meeting is that the current established way we manage glaucoma is now being challenged. Maybe laser therapy will replace medication as first line treatment one day? Perhaps glaucomacologists will also play a significant role in managing ocular surface disease. Whatever the outcomes, this can only be good for providing the best possible care to our patients.