Evidence Report/Technology Assessment                                              

Number 38

Treatment of Coexisting Cataract and Glaucoma

Prepared for: 

Agency for Healthcare Research and Quality

U.S. Department of Health and Human Services

www.ahrq.gov

Contract No. 290-97-0006

Prepared by:

Johns Hopkins University Evidence-based Practice Center, Baltimore, MD

Principal Investigator

Henry D. Jampel, M.D., M.H.S.

Investigators

Lisa H. Lubomski, Ph.D.

David S. Friedman, M.D., M.P.H.

Karen A. Robinson, M.Sc.

Nathan Congdon, M.D., M.P.H.

Harry A. Quigley, M.D.

Hanna Levkovitch-Verbin, M.D.

John Kempen, M.D., M.P.H.

Eric B. Bass, M.D., M.P.H.

AHRQ Publication No. 03-E041

June 2003

This document is in the public domain and may be used and reprinted without permission except those copyrighted materials noted for which further reproduction is prohibited without the specific permission of copyright holders.

Suggested Citation:

Jampel H, Lubomski L, Friedman D. Treatment of Coexisting Cataract and Glaucoma. Evidence Report/Technology Assessment Number 38. (Prepared by Johns Hopkins University Evidence-based Practice Center under Contract No. 290-97-0006.)  AHRQ Publication No. 03-E041. Rockville, MD:  Agency for Healthcare Research and Quality.  June 2003.

Preface

	The Agency for Healthcare Research and Quality (AHRQ), through its Evidence-Based Practice Centers (EPCs), sponsors the development of evidence reports and technology assessments to assist public- and private-sector organizations in their efforts to improve the quality of health care in the United States.  The reports and assessments provide organizations with comprehensive, science-based information on common, costly medical conditions and new health care technologies.  The EPCs systematically review the relevant scientific literature on topics assigned to them by AHRQ and conduct additional analyses when appropriate prior to developing their reports and assessments.

	To bring the broadest range of experts into the development of evidence reports and health technology assessments, AHRQ encourages the EPCs to form partnerships and enter into collaborations with other medical and research organizations.  The EPCs work with these partner organizations to ensure that the evidence reports and technology assessments they produce will become building blocks for health care quality improvement projects throughout the Nation.  The reports undergo peer review prior to their release.  		 	

	AHRQ expects that the EPC evidence reports and technology assessments will inform individual health plans, providers, and purchasers as well as the health care system as a whole by providing important information to help improve health care quality.

	We welcome written comments on this evidence report.  They may be sent to: Director, Center for Practice and Technology Assessment, Agency for Healthcare Research and Quality, 6010 Executive Blvd., Suite 300, Rockville, MD 20852.

Carolyn M. Clancy, M.D.							

Director										

Agency for Healthcare Research and Quality					

Structured Abstract

Objectives. Cataract and glaucoma are ocular diseases that often coexist, with prevalences over age 40 of 20 percent and two percent, respectively.  There is no agreement concerning their optimal management when coexistent.  We prepared this evidence report to: identify the important questions pertinent to surgical treatment of coexisting cataract and glaucoma; assess the quality and content of evidence on surgical treatment of coexisting cataract and glaucoma; and inform clinical practitioners and identify areas for future research.

Search Strategy. The searches were conducted on publications from 1980 to April 2000 using two electronic databases, PubMed and CENTRAL.  Text words and Medical Subject Heading (MeSH) search terms used included (“cataract” and “glaucoma”) and (“surgery” or “filtering surgery” or “cataract extraction” or “sclerostomy” or “trabeculectomy” or “phacoemulsification”).  We included variants of “randomized controlled trials” in the search as well as “case report” and “case series”.  The electronic searches were augmented by a hand search of primary journals.

Selection Criteria.  Two individuals independently reviewed each abstract.  The exclusion criteria were: no human data, lack of adults, lack of original data, failure to address open- angle or primary angle- closure glaucoma, not a controlled trial nor a case series greater than or equal to 100 eyes, only addressing intracapsular surgery, only addressing full-thickness procedures, was a meeting abstract, and not in English. 

Data Collection and Analysis. Two data abstraction forms were developed.  The 25 question quality assessment form was divided into the following categories: representativeness, bias and confounding, description of therapy, outcomes and followup, and statistical quality and interpretation.  A content assessment form was developed through an iterative process.

Each article was reviewed by two reviewers, at least one trained in research methodology and at least one trained in ophthalmology.  Quality scores for each controlled trial and cohort study were tabulated.

For each study question one member of the analysis team summarized the extracted data and formulated a conclusion about the answer to each question.  For each conclusion, the entire study team assigned an evidence grade of A (strong), B (intermediate), C (weak), or I (insufficient).   

Main Results. There was strong evidence that glaucoma surgery is associated with an increased risk of postoperative cataract; moderately strong evidence that mitomycin-C, but not 5-fluorouracil is beneficial in combined procedures, limbus- and fornix-based conjunctival incisions are equally effective for lowering IOP, and the size of the phacoemulsification incision is not important; and weak evidence that combined procedures using phacoemulsification rather than nuclear expression result in lower long-term IOP, as do two-site compared to one-site combined procedures.

Limitations of the literature included lack of optic nerve and visual field data, lack of objective description of the ocular lens, inconclusive information on complications, lack of patient preference and quality of life data, and limited followup in many studies.

Conclusions. The literature does not point to one optimal strategy for controlling IOP in patients with coexisting cataract and glaucoma needing surgery.  Therefore, there is a continued need for high quality studies with greater duration and more information on optic nerve and visual field findings.

Contents

		Summary	1

Evidence Report			

		Chapter 1:  Introduction	9

			Background	9

			Purpose of Evidence Report	9

		Chapter 2: Methodology	11

			Recruitment of Experts	11

			Patient Population	11

			Identifying the Specific Questions	11

			Causal Pathway	12

			Literature Search Methods	12

				Sources	12

				Search Terms and Strategies	12

	Abstract Review	13

			Article Review	14

				Selection of Articles	14

				Abstraction of Qualitative and Quantitative Data	15

			Evidence Tables	15

			Grading the Evidence	16

			Meta-analysis	17

			Supplemental Analyses	17

			Figure 1. Causal Pathway of Treatment of Coexisting Cataract & Glaucoma	18

Chapter 3: Results	19

			Design and Focus of the Studies	19

			Results of the Studies	20

           		Evidence Table 1: Overall summary of the literature on treatment of

			coexisting cataract and glaucoma	20

				Evidence Table 2: Summary of interventions reported in literature on treatment of coexisting cataract and glaucoma	20

				Evidence Table 3: Methodologic quality of literature on treatment of coexisting cataract and glaucoma.	21

				Evidence Table 4: What is the effect of cataract surgery (with or without other procedures/treatments) on long-term intraocular pressure control in open- angle glaucoma patients?	21

				Evidence Table 5: What is the effect of cataract surgery (with or without other procedures/treatments) on short-term intraocular pressure control in open- angle glaucoma

					patients?	28

				Evidence Table 6: What is the effect of glaucoma surgery on the development and progression of cataract?	30

				Evidence Table 7: What is the effect of mitomycin-C on intraocular pressure 

					control after combined cataract and glaucoma surgery?	32

				Evidence Table 8: What is the effect of 5-fluorouracil on intraocular pressure 

					control after combined cataract and glaucoma surgery?	34

				Evidence Table 9: Which cataract or combined procedure techniques lower intraocular pressure the most?	35

				Evidence Table 10: Is intraocular pressure lowered more by a staged glaucoma 

					and cataract surgery or by simultaneous cataract and glaucoma surgery?	38

				Evidence Table 11: Does trabeculectomy combined with cataract surgery or another operation combined with cataract surgery lower intraocular pressure more?	39

				Evidence Table 12: Complications of treatment for coexisting glaucoma and 

					cataract	39

		Figure 2. Summary of searches, abstract review, and literature review	44

Chapter 4: Conclusions	45

	Principal Findings	45

			Limitations of the Literature	46

				Long-term Control of Iop	47

				Short-term Iop Control	47

				One- versus Two-site Surgery	47

				Simultaneous versus Sequential Cataract and Glaucoma Surgery	47

				Mitomycin-C in Combined Procedures	47

				Trabeculectomy Combined with Cataract Surgery Compared with Other Types of Glaucoma Surgery Combined with Cataract Surgery	48

			Implications	48

Chapter 5: Future Research	49

References	51

		Evidence Tables	61

			Evidence Table 1: Overall summary of the literature on treatment of coexisting

				cataract and glaucoma	63

	Evidence Table 2: Summary of interventions reported in literature on treatment of

		coexisting cataract and glaucoma	109

	Evidence Table 3: Methodologic quality of literature on treatment of coexisting

		cataract and glaucoma.	143

	Evidence Table 4: What is the effect of cataract surgery (with or without other

		procedures/treatments) on long-term intraocular pressure control in 

		open-angle glaucoma patients?	157

	Evidence Table 5: What is the effect of cataract surgery (with or without other

		procedures/treatments) on short-term intraocular pressure control in 

		open-angle glaucoma patients?	173

	Evidence Table 6: What is the effect of glaucoma surgery on the development and

		progression of cataract?	182

	Evidence Table 7: What is the effect of mitomycin-C on intraocular pressure 

		control after combined cataract and glaucoma surgery?	191

	Evidence Table 8: What is the effect of 5-fluorouracil on intraocular pressure

		control after combined cataract and glaucoma surgery?	195

	Evidence Table 9: Which cataract or combined procedure techniques lower

		intraocular pressure the most?	199

			Evidence Table 10: Is intraocular pressure lowered more by a staged glaucoma and cataract surgery or by simultaneous cataract and glaucoma

		surgery?	207

	Evidence Table 11: Does trabeculectomy combined with cataract surgery or another

		operation combined with cataract surgery lower intraocular pressure more?	209

	Evidence Table 12: Complications of treatment for coexisting glaucoma and

		cataract	211

Acronyms and Abbreviations used in the Evidence Tables	241

Bibliography	243

Appendixes	255

	Appendix A: Peer Review Representatives of Stakeholder Organizations	257	

	Appendix B: Question Refinement Mailing	261

	Appendix C: PubMed Core Strategy	267

	Appendix D: Priority Journals	271

	Appendix E: Treatment of Coexisting Cataract and Glaucoma Abstract 

		Review Form		275

	Appendix F: Treatment of Coexisting Cataract and Glaucoma Article Quality

		Assessment Form	279

	Appendix G: Treatment of Coexisting Cataract and Glaucoma Article Content

	        Abstraction Form	287

			Appendix H: List of Questions Addressed by Literature Review and Associated 

		Evidence Tables	309

	Appendix I: Initial Evidence Grade Assignments	313

	Appendix J: Searching Summary	317

	Appendix K: Reasons for Exclusion During Abstract Review Process	321

	Appendix L: Study Topics Assigned During Abstract Review	325

	Appendix M: Articles Excluded During Quality Assessment	 					329

	Appendix N: Reasons for Exclusion During Quality Assessment	333

	Appendix O: Study Topics Assigned During Quality Assessment	337

	Appendix P: Article Summary Information for Study Topics	341

	Appendix Q: Quality Assessment Category Scores	345