The Education Committee carefully selects presentations from the WGC-2019 for your benefit. This month Carolina Gracitelli introduces the sessions: Convince your government and payors that what you do is useful & cost-effective, Managing the Glaucoma Suspect and Update on Imaging: Seeing is Believing.
Convince your government and payors that what you do is useful & cost-effective
This section is a great discussion about how to manage the useful and cost of some treatments. The presenters are Dr. Jennifer Burr, Dr. Simon Skalicky, Dr Randy au Craven, and Dr Anja Tuulonen.
Comparing the effectiveness of treatment alternatives
Dr. Jennifer Burr spoke about how new medications; new devices or laser technology may be implemented in the healthy system. So, the great question is how we will decide about which treatment should be adopted? Different issues such as the population, or expertise of community may affect the decision. Different questions should be done to decide: The first important point is the efficacy: “Does the treatment work in the real word?” Another point is the safety. And another question is the cost. She also talked about the time of the outcome. “In two, or in three years?” Ideally, they should look to randomized clinical trial to guide their decisions. She said that in the healthy system they have to do decisions because they work with a limited budged. However, cost alone does not means anything, it is always linked with benefits or not. She illustrates with an example of treatment for glaucoma with medications or laser, not only the intraocular pressure is important but also the quality of life/disability and lifetime.
How do I measure the utility of my efforts?
Dr. Simon Skalicky from Australia started defining utility. In brief, he said that once you have a patient’s choice you could convert to a score. 0 means death and 10 means perfect healthy. He explained that there are several ways to measure utility. He summarized some of the questionnaires that we could measure the utility. There are several questionnaires for vision specifically and also for glaucoma specifically. Glaucoma index utility is one of them, specifically for glaucoma. The most common questionnaire for vision specifically is NEI VFQ-25 and he point out some specific characteristics of this very clever questionnaire. One negative point for these utility score is that when you have a good amount of patients sometimes we do not have significant difference between groups. He emphasized that when we are performing quality of life studies we need to think critically what questions we are doing; maybe we are not doing the right questions. Finally Rasch analysis is a good way to analyze these questions.
My government doesn’t pay for MIGS – what do I do?
Dr. Randy au Craven from USA spoke about the level of the disease, and the cost about use MIGS. He mentioned about the cost that is a way to approach the government, giving the example of India’s studies. He also said the key point is that how a patient may return to work with restriction with a trabeculectomy? Or with less quality of life? He said that, in future studies we should look at to these two points. More studies with safety should be done, although there is no evidence of unsafely. And more clinical trials should be done showing the cost effectives of these devices.
Fostering sustainable glaucoma care
Dr Anja Tuulonen started saying that the first thing we need is attitude. The process is really long. She mentioned about the financial resources, which is an important issue for the process. She also discussed about many governments do not know what we are doing but we are responsible from people of our healthy system, therefore we are part of the problem and part of the solution. There is a great diversity from different countries all around the world, so this is a very complex issue to discuss. She gave examples of what they have done in Finland, how they developed metrics to know if they are in the right direction. She invited us to collect our own data and then we will really measure what we are doing in our every day clinics.
Update on Imaging: Seeing is Believing
This section is about the role of imaging in glaucoma disease presented in the 8th World Glaucoma Congress. The presenters are Dr. Lisandro Sakata, Dr. Eun Ji Lee, Dr Harsha Rao, Dr Alex Huang, and Dr. Kouros Nouri-Mahdavi.
Anterior Segment Imaging
Dr Lisandro Sakata spoke about the use of OCT to assessment of the angle. Angle closure glaucoma is usually a more aggressive disease compared to open angle glaucoma. He emphasized that we should detect the eyes that are suffering the angle closure process and treat them. Gonioscopy is the standard method to evaluate the angle, however is not properly performed by many of us. So, there is a clear need to improve the evaluation of angle or maybe associate alternative methods to access the angle. OCT for angle is easy and quick to perform. You can use OCT to document or follow the patient. He said that OCT could give us qualitative (open or not) and quantitative (with different parameters) results. Case control studies already showed good agreement between anterior OCT and gonioscopy. He also describe how the technology improved from time domain to swept source domain for the new parameters of anterior OCT. However, until nowadays we do not know how to incorporate these new parameters in our daily clinic. Finally, he alerts us the controversial decision of clear lens extraction in these patients with angle closure.
Considerations for Imaging the Myopic Eye
Dr Ein Ji Lee started talking about the glaucoma damage in myopic eyes are very challenging because the anatomic aspects of the optic nerve and the retinal nerve fiber layer (RNFL) interfere in the proper evaluation. She present some studies showing that because of the big peripapillary atrophy the macular evaluation using OCT could be better compared to RNFL thickness in glaucoma evaluation. The number false positive in OCT in myopic eyes are relatively frequent because myopic eyes have different pattern in RNFL thickness and usually they are out of the normative database. Bruch membrane opening (BMO) could also be a good option for these eyes. She presented a result of one study showing less false positive using BMO instead of RNFL thickness. In addition, she presented about the OCT angiograph as an alternative of red free photograph in high myopic eyes. Finally, she said that we have to consider the normative pattern of myopic eye (tilted disc and peripapillary atrophy), which may result in segmentation error and try to find strategies to better evaluation myopic eyes such as OCT angiography or other tests.
OCT Angiography: evolution or revolution
Dr Harsha Rao started explaining the technology behind the OCT angiography. The technology is usually used to visualize the vessels in the choroid, the vessels in macular area and in the optic disc. He summarized the utility of angiography in the glaucoma progression. He gave some examples of OCT angiography in glaucoma patients. Multiple studies tried gave some quantitative data for OCT angiograph. Another studies that he pointed were the OCT angiography for choroid layer. Some OCT angiography findings were associated with glaucoma severity. He said that in patients with floor effect in the retinal nerve fiber layer thickness you could still see angiography reduction.
Seeing where the aqueous is flowing
Dr Alex Huang spoke about the importance to know where the aqueous flow. He said they bored the idea from retina using the same photograph and fluorescein and he presented a video with enucleated eye show the aqueous outflow. Of course, ever person and ever eye can be different, therefore in labor studies they tried to find a pattern of aqueous outflow and they succeed. The next step in their researches was to simulate a real life, in human. So, they brought the idea of using OCT in any body position (for example in an operation position), and they validated the pattern of aqueous outflow. The found a new behavior: the outflow is dynamic, there is a system but the regulation is unknown. The next step was going to human research. The evaluated the aqueous outflow during the cataract surgery. He also tried to association the high and low IOP with aqueous outflow. They could not find association but what he could say until now is that after trabeculectomy there are many types of angiography outflow improvement.
Role of macular imaging in glaucoma
Dr. Kouros Nouri-Mahdavi started illustrating the talk with a case of a woman with normal tension glaucoma that was diagnosed by macular OCT. He emphasized that 50% of our ganglion cells are located in the macular area. In addition, the macular area is easer to segment instead of complex area of optic disc. He provided some specific details about macular segmentation of Spectralis, Cirrus. Regarding detection of progression specific in advanced glaucoma, macular imaging may be a better option instead of retinal nerve fiber layer thickness. He said that the guided progression analysis available by Cirrus OCT is the most solid software for progression that we have available. And he compared different accuracy for macular layers segmentation. To summarize he proposed that the best macular outcome to detect glaucoma progression is the ganglion cell complex (regardless the severity of the disease).
Managing the Glaucoma Suspect
This section is a great discussion about how to deal with glaucoma suspects and how to approach and follow these patients. The presenters are Dr. Bill Morgan, Dr Lucy Shen, Dr. Syril Dorairaj, and Dr Albert Khouri.
Mimickers of Glaucomatous Optic Nerves
Dr. Bill Morgan started showing some cases about suspects’ optic discs. He showed some anatomic changes that happen in the terms of excavation or neural rim in suspects. He showed some examples that happen in high myopic patients regarding excavation and how trick is to differentiate glaucoma. Another example that he gave was about the large disc with large excavation. He gives some alternatives test to help us (or may not) such as visual field or color test, to decide if it is glaucoma or not. He also presented a case of optic chiasm compression that could also be misdiagnosed by glaucoma. He finished the presentation showing a case that OCT scan in the optic disc helped him to diagnosed a patient with glaucoma.
Considerations for the myopic glaucoma suspect
Dr. Lucy Shen started the presentation with two interesting cases. One case was about a patient with high myopic eye that recently used topical steroid. Second case was about high myopic eye with thin central cornea thickness and was treated by glaucoma for years but after some years they considered not glaucoma and stopped using medications. These two cases illustrate the challenging of diagnosis glaucoma in high myopic patients. She explained some anatomic variations in myopic patients and she linked with the difficult to diagnosis. She emphasized that we always have to try to find the neural rim tissues, but do not look to the colors. And try to find changes over time, be consistent with the same exams. In addition, the nerve fiber layer thickness in these patients is off-center and could be a red disease. Regarding glaucoma progression and myopic, she said that some aspects of optic disc (such as tilted disc) may progress over time measured by visual field. She presented some results about disc hemorrhage in myopia. Finally, she said that if you careful analyze fundoscopy, identify the false positives in OCT, continually monitoring patients over time with visual field we may reach the correct diagnosis.
OCT is best for managing glaucoma suspects
Dr. Syril Dorairaj he started saying that he would give us some facts to how to use the OCT in our daily clinic. He gave some examples of optic disc and how we used to diagnosis in the past. Some cases are really easy to diagnosis but some cases are more challenging. The goal is try to diagnosis earlier than we used to do in the past. He explained the Felipe Medeiros’s paper that he presented patients with visual field defect and looked to the past to see if they had retinal nerve fiber layer before the functional loss. He recommended looking the structure measures because that can happen before functional damage. He asked us “if there is a progression in retinal nerve fiber layer (RNFL) thickness, what happen?” He cited one paper published by Carolina Gracitelli with Felipe Medeiros saying that if you have RNFL loss you decrease the quality of life. Structural damage can precede functional damage.
Visual Fields are best for managing glaucoma suspects
Dr Albert Khouri started saying that he would try to convince us to do both: structure and functional analysis in glaucoma. The best test for one patient depends on the stage of the disease. In the very beginning the visual field would not help us, but the retinal nerve fiber layer thickness could. He said that nowadays we know that we have damage in central field in glaucoma even in early stages. He presented a research that RNFL thickness detected progression as well as visual field. And looking at this particular study, visual field and OCT were done in every single visit. He emphases that not every red in OCT is a real disease, some cases such as tilted disc or peripapillary atrophy may be challenging for OCT and in these cases visual field by help us. He said that in EMGS, visual field was very helpful to detect progression. Finally, visual field can be very useful even in the early process.
