The Education Committee carefully selects presentations from the WGC-2019 for your benefit. This month Eytan Blumenthal introduces the sessions: Analyzing the evidence, Going with the flow? OCT-A and other emerging technologies in glaucoma management and Updating the evidence on MIGS.
Analyzing the evidence
Three interesting talks discuss statistical analysis concepts as they pertain to medicine and glaucoma. This session will assist you in brushing up your statistical understanding to become a more critical reader (and writer), and sharpen your ability to extract clinically meaningful conclusions from statistically meaningful data.
Dr. Steve Mansberger opens the session, discussing, in a quiz format, several basic statistical flaws in manuscripts that are submitted for publication, and explains key concepts worth brushing up for more critical reading of published work. This talk is relevant for both author and reader of “statistically spiced” research.
Next, Dr. Paul Healey discusses meta-analyses, the art (or rather science) of combining multiple studies conducted to answer a clinical question, but might not share an identical study design, recruited population, and often differ in outcome. Such analysis is crucial when the literature results differ, as well as when each particular study cannot answer the question, due to insufficient power.
Last, Dr. Alan Robin zooms in on the topic of interpreting research conducted to evaluate surgical outcomes. Dr. Alan points out aspects worth considering before accepting a procedure as safe and effective, such as the patient’s perspective, as well as considering biases that might creep into such studies.
Going with the flow? OCT-A and other emerging technologies in glaucoma management
Five fascinating talks describe OCT angiography as it pertains to glaucoma, from the very basics to its clinical potential in glaucoma diagnosis and follow-up for progression.
Dr. Leopold Schmetterer starts out by explaining how the doppler principle enables us to assess blood flow in vessels, providing a historical perspective on the development of this ability, discussing how these physics principles translate into our ability to now measure slow flow rates and even discuss perfusion of tissues.
Next, Dr. Monisha Nongpiur discussed the experience of her group, as well as other studies evaluating OCT-A findings in drainage blebs, contrasting functional blebs as opposed to scarred blebs. She further differentiates superficial flow as opposed to deeper flow within the bleb, discussing the potential prognostic value on the survival of a filtration bleb.
Dr. Joao Barbosa Breda spoke about blood flow in glaucoma as captured using OCT-A technology, as reflected using data he collected. A discussion of potential artifacts, variability and interpreting the flow data will assist the clinician new in interpreting OCT-A to realize the potential and the extent to which this data can assist us in the clinic.
Dr. Grace Richter next discussed the role of OCT-A in clinical practice, analyzing data and presenting specific cases, correlating and distinguishing diagnostic abilities and differences between OCT and OCT-A. Systemic and non-glaucomatous associations, such as diabetes and myopic are further discussed. Last, individual patient data is presented, highlighting the value of the OCT-A scan.
In the last talk of this session, Dr. Anne Brooks, reviews the field of fluorescein angiography anterior segment angiography, followed by a discussion on whether OCT-A may, in the future, provide a viable non-invasive replacement to anterior segment FA.
Updating the evidence on MIGS
Six excellent talks analyze outcomes of MIGS surgical procedures.
Dr. Henny Beckers summarizes her technique, experience, efficacy, safety profile and adverse effects with the Preserflow microshunt (formerly InnFocus), an ab-externo subconjunctival bypass procedure.
Next Dr. Andrew White describes his experience with the Xen, an ab-interno subconjunctival bypass. He shares his technique, highlights his approach for precise placement of the device, the post-operative management and options when adverse effects occur. Dr. White finalizes his talk with a discussion of three cases, each highlighting a management dilemma.
Dr. Ron Fellman discusses canal surgery, aimed at reducing the resistance of the inner wall of Schlemm’s canal, via obliteration cleavage or cannulation, 10 such technologies are presented, highlighting similarities and unique aspects of each.
Suprachoroidal devices were next presented by Dr. Antionio Fea, highlighting their advantages and limitations, including the Cypass that was removed from the market. The advantages and limitations of the suprachoroidal space for filtration is discussed, and novel devices, some not commercially available yet, presented.
Dr. Chelvin Sng discussed trabecular bypass surgery, stents draining aqueous from the anterior chamber to Schlemm’s canal, considered the natural site for increase resistance in glaucoma. Data is presented, demonstrating the efficacy of the different devices and generations.
Last, Dr. Tarek Shaarawy discussed patient oriented outcomes for successful glaucoma surgery, as they refer to the MIGS era, a refreshing view from our patients’ view. He highlights how endpoint and concepts obvious to the physician may not be so straightforward and clear to the patient, and vice versa.