The Education Committee carefully selects presentations from the WGC-2019 for your benefit. This month Monisha Nongpiur introduces the sessions: How glaucoma affects our patients, Normal Tension Glaucoma Symposium and The Future of Glaucoma Assessment.
How glaucoma affects our patients
This session explores the various ways glaucoma impact patients; and highlights the need for their assessment and for clinicians to consider them during clinical decision making processes.
Measuring quality of life quicker and better through computer adaptive testing
Dr Lamoureux started the session with a very interesting talk on using item banking and computerised adaptive testing (CAT) for measuring patient related outcome measures (PROM) in Ophthalmology. He described the different phases of the development, testing, evaluation and implementation of the CAT specific for glaucoma (GlauCAT). He concluded by summarizing the benefits of using CAT instead of the traditional paper-pencil questionnaires for collection of PROM data.
Real-world evaluation of drivers with glaucoma
Dr Wood spoke about the impact of glaucoma on driving ability and safety. She shared her research on open road driving assessment in patients with mild-moderate glaucoma. Whereas glaucoma patients were rated as less safe than controls, however, none of the standard vision tests were predictive of the driving performance or safety ratings. She concluded that a plausible explanation could be the ability to compensate for field loss through eye movements in some drivers.
Measuring patient’s disease perception in practice and research
In her talk, Dr Vijaya Gothwal stressed on the importance of reducing the gap between patient experiences’ and physicians’ perception on disease, in order to enable as well as improve participation in shared decision making. Dr Gothwal then described the various ways to measure patients’ participation in the clinic and research settings, including the processes for implementing and administration of PROMs.
The numerous ways in which glaucoma affects our patients
Dr Skalicky also draws attention to the disparity on what glaucoma is to patients and to clinicians; and highlights some of the difficulties and apprehensions glaucoma patients with visual field defect experience. He conveys the importance of assessing the presence of other ocular conditions, systemic co-morbidities, psychological and economic impact of glaucoma and glaucoma treatment, and their influence on the quality of life of the patients.
Fear, falls, fractures & physical activity in glaucoma
Dr Friedman ended the symposium by discussing the impact of vision loss on disabilities including impaired mobility, physical activities, falls and fear of falling. Loss of independence and reduction of physical activity can have a profound effect on the quality of life and is associated with increased mortality and cognitive decline. Dr Friedman emphasized the importance of patient education, dealing with their impairments and disabilities, and referral for rehabilitation since disability precedes blindness.
Normal Tension Glaucoma Symposium
An excellent session covering the different aspects of Normal Tension Glaucoma from terminology, genetic aetiology, management approaches to challenging case scenarios. The session started with a very interesting debate on whether the term ‘Normal Tension’ should be discarded.
Normal Tension – should we bury the term? – Pro
Speaking in favour of the proposition, Dr Quigley elucidated the various problems with using the term ‘Normal tension glaucoma’. Given that the majority of glaucoma occurs at the ‘normal’ IOP range, he emphasized that it is the level of IOP rather than elevated IOP that is important, and treatment should involve establishing baseline IOP, and setting the target IOP based on disease severity.
Normal Tension – should we bury the term? – Con
Countering the motion, Dr Kamal demonstrated that NTG is a separate disease entity in terms of phenotypic features, aetiology, genetic predisposing and disease management. She highlights the need for more research in NTG directed towards identifying contributing mechanisms and novel therapeutic modalities.
Genetics and biology of NTG
Dr Araie spoke about the biology of the different genes associated with NTG that were identified from linkage studies, candidate gene approach, and genome-wide association studies (GWAS). He also discussed the differences in some of the NTG-associated SNPs in Japanese and Caucasian populations.
Systemic risk factor modification and non-IOP lowering treatments in the management of NTG
Dr Chan-Yun Kim spoke about the various IOP-independent mechanisms that are associated with the development of NTG, and their associations with disease progression. He then discussed the role of systemic risk factor modifications and non-IOP dependent treatment modalities in the management of NTG.
Deciding on a target IOP in NTG, and achieving it safely without complications
Dr Yamamoto discussed the findings from their long-term longitudinal studies of patients with NTG treated with trabeculectomy. He showed that the target IOP should be 9-10mmHg, is safe and associated with slower rates of visual field progression. In cases with late-stage NTG with relatively low IOP, Dr Yamamoto showed that trabeculectomy-MMC was safe and effective in stabilizing visual function.
Challenging cases in NTG
Dr Sugiyama ended the session by presenting an excellent array of challenging cases in NTG diagnosis and management. Despite seemingly adequate IOP control, some eyes continued to progress. He highlighted the effectiveness of using a prediction formula to estimate the rate of future visual field progression. In order to better diagnose glaucoma in eyes with high myopia, Dr Sugiyama suggests that it is essential to correct for magnification as well as to use the long axial length database to accurately estimate RNFL thickness.
The Future of Glaucoma Assessment
Another interesting session with points-counterpoints for two different assessment modalities for glaucoma. The first was on the macula versus optic nerve, and the second on fundus photos versus OCT. They were followed by talks on electrophysiology, and, the future options for glaucoma assessment.
Assessing the Macula is Better than Assessing the Optic Nerve
Speaking on why assessing the macula is preferred over the optic nerve, Dr de Moraes began his talk by stating that glaucoma management requires both macula and ONH assessments. He then discussed the importance of assessing the macula and showed that macular damage not only occurs in advanced glaucoma but also in early disease, and can be assessed by both OCT and visual field, and their combinations. Evaluating the ONH alone may miss some of the glaucoma-related macular damage. He also highlighted the ability of the macular scans to detect progression in advanced glaucoma, and may be preferable to the ONH parameters due to the floor effect of advanced disease. He concluded that since current technologies combine both macula and ONH scans in the same machines, they should both be used for detection and monitoring of progression.
Assessing the Optic Nerve is Better than Assessing the Macula
Dr Dorairaj also echoed similar views that both macula and ONH should be assessed to detect and monitor glaucoma. He emphasized that traditionally, the ONH is evaluated for assessment of glaucoma and discussed the need to look at surrogates for detection of glaucoma progression. He concluded that macular alone may not be sufficient to detect glaucoma, and evaluation of RNFL and other ONH parameters are still preferable.
Fundus Photos are Better than OCT
Dr Kaushik highlighted the benefits of detailed clinical examination of the disc and fundus for the accurate assessment of changes associated with glaucoma. She showed several examples and situations that alluded to the limitations of the OCT to either detect glaucoma or monitor progression. She cautions the interpretation of OCT results especially in patients with small crowded discs and in those with peripapillary atrophy.
OCT is Better than Fundus Photos
On OCT being a better assessment tool than fundus photo, Dr Kim Tae-Woo highlighted the advantages of the OCT in the evaluation of eyes with media opacity, high myopia and diffuse RPE atrophy. He showed the ability of macular imaging to discriminate glaucoma in highly myopic eyes and also described the feasibility of deep layer imaging of the lamina cribrosa morphology and deformation, to detect glaucoma and predict progressive RNFL loss.
Electrophysiology is the Best Assessment of Visual Function
Continuing on the topic of glaucoma assessment, Dr Fortune presented several advantages of Electrophysiology as an assessment tool for visual function. He presented findings from several longitudinal studies that revealed some degree of reversibility of retinal ganglion cell dysfunction after IOP reduction. He also showed the value of pattern ERG to predict progression (visual field and RNFL thickness) but cautions their limitation as a tool to monitor glaucoma progression since electrophysiological changes occur early and then saturate. The other advantage of electrophysiology is the ability to assess outer retinal function which is not possible with the visual field.
Future Options for Glaucoma Assessment
Dr Skalicky ended the session by introducing several devices and technologies that could be future options for glaucoma assessment. The devices included computerised VF testing, virtual reality and tablet-based tests that were under different stages of development, testing and validation. In the future, it would be interesting to see whether these new technologies can better detect glaucoma and monitor disease progression.
