Reporting Complications in Glaucoma Surgery: A Systematic Review

European Glaucoma Society - A guide on surgical innovation for glaucoma

PROLOGUE: Glaucoma surgery has been, for many decades now, dominated by the universal gold standard which is trabeculectomy augmented with antimetabolites. Tubes also came into the scene to complement what we use to call conventional or traditional glaucoma surgery. More recently we experienced a changing glaucoma surgery environment with the "advent" of what we have become used to calling Minimally Invasive Glaucoma Surgery (MIGS). What is the unmet need, what is the gap that these newcomers aim to fill? Hippocrates taught us "bring benefit, not harm" and new glaucoma techniques and devices aim to provide safer surgery compared to conventional surgery. For the patient, but also for the clinician, safety is important. Is more safety achieved with new glaucoma surgery and, if so, is it associated with better, equivalent, or worse efficacy? Is new glaucoma surgery intended to replace conventional surgery or to complement it as an 'add-on' to what clinicians already have in their hands to manage glaucoma? Which surgery should be chosen for which patient? What are the options? Are they equivalent? These are too many questions for the clinician! What are the answers to the questions? What is the evidence to support answers? Do we need more evidence and how can we produce high-quality evidence? This EGS Guide explores the changing and challenging glaucoma surgery environment aiming to provide answers to these questions. The EGS uses four words to highlight a continuum: Innovation, Education, Communication, and Implementation. Translating innovation to successful implementation is crucially important and requires high-quality evidence to ensure steps forward to a positive impact on health care when it comes to implementation. The vision of EGS is to provide the best possible well-being and minimal glaucomainduced visual disability in individuals with glaucoma within an affordable healthcare system. In this regard, assessing the changes in glaucoma surgery is a pivotal contribution to better care. As mentioned, this Guide aims to provide answers to the crucial questions above. However, every clinician is aware that answers may differ for every person: an individualised approach is needed. Therefore, there will be no uniform answer for all situations and all patients. Clinicians would need, through the clinical method and possibly some algorithm, to reach answers and decisions at the individual level. In this regard, evidence is needed to support clinicians to make decisions. Of key importance in this Guide is to provide an overview of existing evidence on glaucoma surgery and specifically on recent innovations and novel devices, but also to set standards in surgical design and reporting for future studies on glaucoma surgical innovation. Designing studies in surgery is particularly challenging because of many subtle variations inherent to surgery and hence multiple factors involved in the outcome, but even more because one needs to define carefully outcomes relevant to the research question but also to the future translation into clinical practice. In addition this Guide aims to provide clinical recommendations on novel procedures already in use when insufficient evidence exists. EGS has a long tradition to provide guidance to the ophthalmic community in Europe and worldwide through the EGS Guidelines (now in their 5th Edition). The EGS leadership recognized that the changing environment in glaucoma surgery currently represents a major challenge for the clinician, needing specific guidance. Therefore, the decision was made to issue this Guide on Glaucoma Surgery in order to help clinicians to make appropriate decisions for their patients and also to provide the framework and guidance for researchers to improve the quality of evidence in future studies. Ultimately this Guide will support better Glaucoma Care in accordance with EGS's Vision and Mission. Fotis Topouzis EGS President

Current Concepts of the Uveitis-Glaucoma-Hyphema (UGH) Syndrome

PURPOSE

To discuss the pathophysiology, etiology, and current management strategies of uveitis-glaucoma-hyphema (UGH) syndrome.

METHODS

Literature review.

RESULTS

The classic UGH syndrome associated with anterior chamber intraocular lenses (ACIOL) have decreased in incidence with the modernization of IOL design and surgical techniques. The current UGH syndrome is increasing in prevalence largely related to a parallel increase in late onset dislocations of intraocular lenses (IOLs) and the developing techniques to remedy that condition. The modern features of UGH can present as cystoid macular edema, intraocular pressure elevation typically not attributed to UGH, and recurrent vitreous hemorrhage, unlike the original description as described by Ellingson in 1978. Medical management to control inflammation, reduce intraocular pressure, and reduced the bleeding diathesis are mainstays of therapy. However, surgery with IOL repositioning or exchange should be reserved for cases that are refractory to or progressing despite medical treatment.

CONCLUSIONS

UGH syndrome is an increasingly common, poorly understood, and often subtle, manifestation of an anatomic disturbance post intraocular surgery that persists with continued evolution of intraocular surgical techniques and new imaging modalities to aid in its diagnosis.

How Can We Quantify and Compare Harm in Surgical Trials?

PURPOSE

To describe methods that can be used to quantify and compare harm caused by surgical interventions in ophthalmology trials.

DESIGN

Perspective study.

METHODS

A published landmark glaucoma trial was used as an exemplar. A consensus-derived classification system of severity of complications was applied to published data of the Tube Versus Trabeculectomy glaucoma trial. The severity grade of each complication was multiplied to the number of patients who incurred that complication to estimate a total harm score for each intervention. Graphical tools were also used to display the differences in complications between trial arms. A review of literature on best practice for reporting harm data was also conducted.

RESULTS

Analyzing treatment harm is challenging with the relatively small number of events and sample sizes used in randomized controlled trials. However, quantification and graphical representation of harm after surgery is possible. Reframing the research question to one for detecting signals of adverse reactions and use of Bayesian analyses can be useful.

CONCLUSIONS

Analysis of harm data in clinical trials needs further attention. A severity classification system and a total harm score can be used to quantify harm after glaucoma surgery. Graphical tools can also help interpret complication data.

Chronic Kidney Disease as a Predictor of Postoperative Choroidal Effusions After Glaucoma Surgery

PRCIS

Patients with chronic kidney disease (CKD) are at increased risk for choroidal effusion development following glaucoma surgery.

PURPOSE

Choroidal effusion is a postoperative complication of glaucoma surgery that results from a transudative fluid collection in the suprachoroidal space. Kidney disease alters bodily fluid dynamics through a variety of mechanisms. The relationship between CKD and choroidal effusion following glaucoma surgery has not previously been studied. The purpose of this study was to determine the relationship between CKD and choroidal effusion development after glaucoma surgery.

PATIENTS AND METHODS

This retrospective cohort study consisted of 86 eyes from 86 patients who received glaucoma filtering surgery or transscleral cyclophotocoagulation within the study timeframe. Forty-three patients had CKD, and 43 patients did not have kidney disease. The main outcome of this study was the development of choroidal effusion measured by the Pearson χ2 test and multivariate analysis using a binomial regression with a log link.

RESULTS

Ten patients (23.3%) in the CKD group developed choroidal effusion, while 2 patients (4.7%) in the no-kidney disease group developed choroidal effusion (relative risk, 5.0; 95% confidence interval: 1.16-21.5; P=0.013). The association between CKD and choroidal effusion showed mixed results in the multivariate analysis, with some analyses showing a significant association and others showing no significant association.

CONCLUSIONS

In both the univariate and multivariate analyses, CKD was found to be significantly associated with choroidal effusion after glaucoma surgery.

Postoperative complications in glaucoma surgery: literature review-based recommendations to improve reporting consistency

AIMS

To recommend a list of complications of glaucoma surgery to be used in future glaucoma surgery research and reporting by exploring the spectrum of complications' names, the variety of definitions and time frames used for reporting them in glaucoma surgical trials.

METHODS

Complications' names, definitions and time frames identified from a previously conducted systematic review of glaucoma surgery trials (registration number: CRD42019121226) were reviewed. Only postoperative complications were considered. Surgical techniques described in the papers from the previous systematic review were retrieved and grouped according their mechanism of action.Reviewers independently recommended each complication's inclusion or exclusion in a list to be proposed as a potential standard for reporting in glaucoma interventions. A literature-based definition of a 'surgical complication' was used to inform these decisions. Recorded complication's details were used to inform the development of clinically relevant definitions, a consensus-driven exercise between reviewers resolved disagreements.

RESULTS

We identified 48/111 (43.2%) of the reported complications as suitable for inclusion, of which 17 were merged into other included complications having a broader meaning making up a final table of 32 postoperative complications. For 25 of them, the authors kept 'names' that were previously used in the systematic review, but provided a definition that was not mentioned in these papers. Five included complications were given both 'names' and definitions not previously mentioned. The authors maintained the name and definition for one complication. There were 16 complications that were in common to all the procedures retrieved from the previous review.

CONCLUSIONS

We propose a table of revised names and comprehensive definitions of postoperative complications, to simplify the process of reporting complications after glaucoma surgery and to improve consistency among surgical trials.