Surgical strategies for coexisting glaucoma and cataract

Article for CME Credit

Surgical Strategies for Coexisting Glaucoma and Cataract An Evidence-based Update David S. Friedman, MD, MPH,1,2 Henry D. Jampel, MD, MHS,1 Lisa H. Lubomski, PhD,1 John H. Kempen, MD, MPH, MHS,1,2 Harry Quigley, MD,1 Nathan Congdon, MD, MPH,1 Hani Levkovitch-Verbin, MD,1 Karen A. Robinson, MSc,2 Eric B. Bass, MD, MPH3,4 Objective: To assess short- and long-term control of intraocular pressure (IOP) with different surgical treatment strategies for coexisting cataract and glaucoma. Design: Systematic literature review and analysis. Method: We performed a search of the published literature to identify all eligible articles pertaining to the surgical management of coexisting cataract and glaucoma in adults. One investigator abstracted the content of each article onto a custom-designed form. A second investigator corroborated the findings. The evidence supporting different approaches was graded by consensus as good, fair, weak, or insufficient. Main Outcome Measures: Short-term (24 hours or fewer) and long-term (more than 24 hours) IOP control. Results: The evidence was good that long-term IOP is lowered more by combined glaucoma and cataract operations than by cataract operations alone. On average, the IOP was 3 to 4 mmHg lower in the combined groups with fewer medications required. The evidence was weak that extracapsular cataract extraction (ECCE) alone results in short-term increase in IOP and was insufficient to determine the short-term impact of phacoemulsification cataract extraction (PECE) on IOP in glaucoma patients. The evidence was weak that short-term IOP control was better with ECCE or PECE combined with an incisional glaucoma procedure compared with ECCE or PECE alone. The evidence was also weak (but consistent) that long-term IOP is lowered by 2 to 4 mmHg after ECCE or PECE. Finally, there was weak evidence that combined PECE and trabeculectomy produces slightly worse long-term IOP control than trabeculectomy alone, and there was fair evidence that the same is true for ECCE combined with trabeculectomy. Conclusions: There is strong evidence for better long-term control of IOP with combined glaucoma and cataract operations compared with cataract surgery alone. For other issues regarding surgical treatment strategies for cataract and glaucoma, the available evidence is limited or conflicting. Ophthalmology 2002;109: 1902–1915 © 2002 by the American Academy of Ophthalmology. Cataract and glaucoma frequently occur in the same patient, raising critical management issues. Are patients better served by combined glaucoma and cataract surgery, or would cataract extraction alone be sufficient? Is it best to establish a bleb before performing cataract surgery? Does

subsequent cataract surgery damage blebs? Should sequential surgery, with cataract extraction followed by filtration surgery at a later date, be the procedure of choice? The lack of consensus among glaucoma specialists regarding the surgical management of coexisting cataract and

Originally received: June 20, 2001. Accepted: May 7, 2002. Manuscript no. 210429. 1 Department of Ophthalmology, Johns Hopkins University, Baltimore, Maryland. 2 Department of Epidemiology, Johns Hopkins University, Baltimore, Maryland. 3 Department of Medicine, Johns Hopkins University, Baltimore, Maryland. 4 Department of Health Policy and Management, Johns Hopkins University, Baltimore, Maryland. This article is based on research conducted by the Johns Hopkins University Evidence-based Practice Center under contract to the Agency for

Healthcare Research and Quality (formerly, Agency for Health Care Policy and Research), contract no. 290-97-0006, Rockville, Maryland. The authors of this article are responsible for its contents, including any clinical or treatment recommendations. No statement in this article should be construed as an official position of the Agency for Healthcare Research and Quality or the United States Department of Health and Human Services.

1902

© 2002 by the American Academy of Ophthalmology Published by Elsevier Science Inc.

Supported by the National Eye Institute, Bethesda, Maryland (grant nos.: K23-EY00358 [DSF], K23-EY00386 [JHK], K23-EY00388 [NC]); and Research to Prevent Blindness, Inc., New York, New York (Robert E. McCormick Award [DSF] and Career Development Award [NC]). Correspondence to David S. Friedman, MD, MPH, Wilmer 120, Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MD 21287. [email protected]. ISSN 0161-6420/02/$–see front matter PII S0161-6420(02)01267-8

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma glaucoma led the American Academy of Ophthalmology to request a systematic literature review of this topic by one of the Evidence-based Practice Centers established by the Agency for Healthcare Research and Quality. A companion article (Jampel HD et al, The Methodologic Rigor of Clinical Trials on Surgical Management of Eyes with Coexisting Cataract and Glaucoma, Ophthalmology 109:1892– 02.) reports on the rigor of the studies reviewed. The purpose of this article was to review and synthesize the published evidence on the effects of different surgical management approaches on short- and long-term intraocular pressure (IOP) control in patients with coexisting cataract and glaucoma.

Methods We searched the literature to identify articles addressing the management of glaucoma patients with coexisting cataract. The methods used to identify and select the studies to be included in this report are described in detail elsewhere.1 Briefly, the search was restricted to studies published from 1964 through March 2000 on adult patients with glaucoma and cataract. Several literature sources were used to identify all studies that potentially were relevant to the surgical treatment of patients with coexisting cataract and glaucoma. The electronic searches were conducted in PubMed and CENTRAL, the Cochrane Collaboration’s database of clinical trials. The searches were augmented by a hand search of peer-reviewed ophthalmology journals that were thought likely to have articles on the topic, of the reference lists of relevant review articles, and of the reference lists of a sample of studies included in the literature review.

Study Eligibility Studies were eligible for review if they addressed the surgical management of adult glaucoma patients with cataract. Studies had to address either phacoemulsification cataract extraction (PECE) or extracapsular cataract extraction (ECCE) in glaucoma patients. We were interested primarily in studies comparing two or more approaches to surgical management of coexisting cataract and glaucoma. However, we also included case series with at least 100 patients to capture potentially important information about complications of the management options. Studies were excluded if they did not report human data, if they reported only on intracapsular cataract extraction, if they did not report original data, or if they were not in English. Studies were also excluded from the present analysis if they were randomized clinical trials comparing modifications of a single surgical approach (such as heparin-coated lenses versus noncoated lenses) that involved fewer than 100 individuals. This analysis was intended to compare the major surgical approaches for cataract management. Future analyses will assess the effectiveness of various surgical modifications.

Study Questions Before conducting the data abstraction, the research team met with outside consultants and stakeholders to determine the specific questions to be addressed by the literature review. The investigators selected the following questions to be answered about shortand long-term IOP control. For short-term IOP control (defined as 24 hours or fewer): 1. What is the effect of cataract surgery alone on short-term IOP in glaucoma?

2. What is the effect of combined cataract and glaucoma operations on short-term IOP control? 3. Do combined cataract and glaucoma operations produce lower short-term IOP than cataract surgery alone? For long-term IOP control (defined as more than 24 hours): 1. What is the long-term IOP-lowering effect of cataract extraction alone in glaucoma patients? 2. What is the long-term IOP-lowering effect of combined cataract extraction and trabeculectomy? 3. Does combined cataract and glaucoma surgery in glaucoma patients lower IOP more in the long-term than cataract surgery alone? 4. Is long-term IOP control better with combined cataract and glaucoma surgery than trabeculectomy alone? 5. Does cataract extraction in patients with functioning filtering blebs negatively impact long-term IOP control in patients with glaucoma?

Content Abstraction We developed an article content assessment form to extract relevant information from eligible studies in a standardized fashion. Surgical Treatment. The content assessment form included information on the technique used in each arm of the study, including the operation performed, surgical location of the trabeculectomy incision, antifibrosis agents used (including dose and duration), iris manipulation, postoperative medications, and method of cataract extraction (including the location of the incision). For endoscopic laser cilioablation, we recorded the number of degrees of the angle that were treated and the power used. For studies addressing short-term IOP control, we recorded the use of viscoelastic agents and IOP-lowering medications during the intraoperative and postoperative periods. Study Results. For short-term IOP control, we abstracted the mean change in IOP at 24 hours after surgery (or at the postoperative visit on the next day). We also recorded the proportion of patients reported to have the IOP rise by 0 to 10 mmHg, 11 to 20 mmHg, and more than 20 mmHg. For long-term IOP control, we recorded all outcomes at the last follow-up that included 50% or more of study participants. However, many studies aggregated the data for subjects at their last follow-up visit. For those studies, this information was abstracted instead. The mean (or median) change in IOP and number of medications used were abstracted along with the proportion achieving a clinical target pressure, an IOP decrease of 30% or more, or an IOP of 21 mmHg or less. Finally, we recorded the proportion of subjects requiring bleb needling or further glaucoma surgery during the follow-up period. We also noted ocular complications, including hypotony, hyphema, wound leaks, and endophthalmitis. Each article was assigned a primary and secondary reviewer; at least one reviewer had training in research methodology, and at least one was a physician with subspecialty training in glaucoma. The primary reviewer performed the initial content abstraction, and the secondary reviewer read the article and checked the findings of the primary reviewer. The two raters reconciled differences through consensus. If a consensus could not be reached, one of the principal investigators served as a third reviewer to adjudicate the disagreement. The reviewers were not masked with regard to the author, institution, and journal because such masking has been demonstrated to be ineffective in removing potential reviewer bias.2 Articles were classified according to study design as randomized controlled trials, nonrandomized controlled trials, cohort studies, or case series. In randomized trials, the treatment is assigned randomly. In nonrandomized controlled trials, the investigators

1903

Ophthalmology Volume 109, Number 10, October 2002 compare two groups receiving treatments to see if they differ in outcome, but the treatments are not assigned at random. Finally, in cohort studies, the authors either prospectively or retrospectively observe the outcomes of individuals with a given exposure (for example, cataract extraction) and compare their results with those without the exposure. Each trial and cohort study was graded for study quality in five domains: representativeness, bias and confounding, intervention description, outcomes and follow-up, and statistical methods and interpretation. We calculated an overall quality score (ranging from 0 to 100) based on the average of the percentage of study quality criteria that were met in each of five domains. Large case series were not graded for quality. A detailed description of the quality grading is presented in a companion article.1

Evidence Grading Based on our review of the eligible studies, the scientific assumptions that underlie justification for a metaanalysis were not met. In particular, the heterogeneity of the study aims, content, design, and most importantly, the way in which the outcomes were measured precluded us from pooling the data in a meaningful or acceptable fashion. We therefore used a consensus approach to grade the evidence. A committee consisting of four glaucoma specialists (three with postgraduate degrees in research methodology), an epidemiologist, an ophthalmologist with a doctorate in epidemiology, and a medical internist with extensive experience in conducting this kind of research independently graded the evidence and then met to achieve consensus. The final results were evaluated then by a panel of experts (including representatives from the American Academy of Ophthalmology and the American Glaucoma Society), with a second meeting held to incorporate comments from these individuals. Finally, the final draft evidence grades were sent to representatives of several stakeholder organizations. The scheme used to grade the evidence was a modification of that used by Garbutt et al3 and more recently by Friedman et al4 in a review of anesthesia management for cataract surgery. For this study, the following evidence grades were used. Grade A (good evidence). Appropriate data were available for evaluating efficacy or safety of the interventions in question; the population of patients studied was sufficiently large, and adequate controls were used; data were consistent and indicated that the efficacy or safety of the intervention has been described accurately; and one intervention was clearly superior, equivalent, or inferior to another in terms of one or more well-defined outcomes. Grade B (fair evidence). Appropriate data were available for evaluating safety or efficacy of the interventions in question; the population of patients studied was sufficiently large; data were reasonably but not entirely consistent and indicated that the efficacy or safety of the intervention had been described accurately; and the data suggested superiority (or equivalence) of one intervention compared with another for a specific, welldefined outcome; but, there was insufficient evidence to conclude definitively whether the efficacy or safety of one intervention was clearly superior or inferior to another. Grade C (weak evidence). Some data were available for evaluation of the safety or efficacy of the interventions in question; the population of patients studied was reasonably large; and data indicated a trend supporting a benefit (or equivalence) of one intervention over another for specific, well-defined outcomes; but, there was insufficient evidence to conclude that one intervention was truly superior (or equivalent) to another. Grade I (insufficient). Appropriate data were not available or

1904

Table 1. Reasons for Exclusion of Articles during Abstract Review Process Exclusion Criterion on Abstract Review Form*

Number Excluded

Did not include human data Adults not part of study population Not in English No original data Does not address open-angle glaucoma or primary open angle-closure glaucoma Was neither a controlled trial nor a case series ⱖ100 patients Only addresses intracapsular cataract extraction Only addresses full-thickness glaucoma surgery Meeting abstract Other (e.g., does not address cataract surgery)

13 0 1 28 483 403 27 2 0 30

* Reviewers did not have to agree on reason for exclusion.

an insufficient number of patients were studied to assess safety and efficacy of the intervention in question alone or in comparison with alternatives. When there was disagreement between the investigators as to the evidence grade, all of the evidence was presented simultaneously to the investigators and consensus achieved through discussion.

Results The initial search identified 919 citations possibly addressing the study topic, of which 131 citations were deemed eligible for full article review. Abstracts were ineligible for full article review if they were not applicable to the study questions (1.8% of excluded abstracts), if the citation met an exclusion criterion (98% of excluded abstracts), or for a combination of the above. Twenty-one of the 131 citations deemed eligible for full review based on the abstracts were later found to be ineligible, leaving a total of 110 articles. An additional 72 articles were randomized clinical trials comparing a single surgical modification (such as the use of an antimetabolite) involving fewer than 100 patients and therefore were excluded from analysis for this paper (but will be reported on in a separate analysis). Articles were excluded most frequently because the study was not a controlled trial or a case series of 100 patients or more, because the study did not report outcomes relevant to the study questions, or because the study did not present original data (Table 1). Summary tables of the 39 articles included in this analysis detail the surgical techniques used, the number of individuals enrolled in each study arm, and the major outcomes reported (see Table 2 for short-term IOP control and Table 3 for long-term IOP control).

Short-term Intraocular Pressure Control (24 Hours or Fewer) Question 1: What Is the Effect of Cataract Surgery Alone on Short-term Intraocular Pressure in Glaucoma Patients? Only one cohort study (quality score, 59%) directly addressed this question.5 Shingleton et al5 reported that IOP decreased a mean of 1.0 mmHg in glaucoma suspects undergoing PECE (75 eyes) and increased a mean of 1.0 mmHg in the glaucoma patients under-

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma Table 2. What Is the Effect of Cataract Surgery (with or without Other Procedures or Treatments) on Short-term Intraocular Pressure Control in Open-angle Glaucoma Patients? Outcomes/Benefits of Surgery

Study Information Propor- Mean (Author, Year; Location; Number tion of Number Mean Follow-up; Quality Study of Eyes Black of Score) Groups Enrolled Patients Prior Study design: Randomized controlled trials Gimbel et al13 1 53 Canada, 1995 Follow-up, 12–23 mos 2 53 Quality, 63% 10 Krupin et al 1 26 USA, 1989 Follow-up, ⱕ24 hrs 2 42 Quality, 54% 12 Storr-Paulsen et al 1 10 Europe, 1998 Follow-up, 6–11 mos 2 10 Quality, 72% Study design: Cohort studies Lyle and Jin9 1 104 USA, 1991 Follow-up, 12–23 mos Quality, 64% 2 112 McGuigan et al7 USA, 1986 Follow-up, 12–23 mos Quality, 40% McKinzie and Boggs6 USA, 1989 Follow-up, ⱕ24 hrs Quality, 30% Murchison and Shields11 USA, 1990 Follow-up, 12–23 mos Quality, 67% Tezel et al8 USA, 1997 Follow-up, 12–23 mos Quality, 40%

1

40

Surgical Interventions

No. No. No. Eyes Eyes Eyes No. 0–10 11–20 ⬎20 Eyes IntraMean mmHg mmHg mmHg Intraoperative Intra- Intra- Intra- Intra- ocular Intraocular Intraocular ocular ocular ocular Pressure Pressure operative Pressure Pressure Pressure Pressure ⱕ21 Medications Viscoelastic Change Increase Increase Increase mmHg

NR

0

Trab/PECE/Scl

None

No

⫺2.2

NR

NR

NR

NR

NR

0

PECE/Scl

None

No

⫺2.0

NR

NR

NR

NR

0.23

0

ECCE/Scl

None

Yes

⫹0.6

5

6

11

4

0.38

0

Trab/ECCE/Scl

None

Yes

⫺5.4

8

3

1

28

NR

0

Trab/PECE/Scl

None

Yes

NR

NR

NR

NR

7

NR

0

PECE/Scl

None

Yes

NR

NR

NR

NR

6

NR

NR

None

Yes

⫺7.8

NR

NR

NR

NR

NR

NR

None

Yes

⫺9.9

NR

NR

NR

NR

NR

NR

PECE 1 site 3-mm incision PECE 1 site 6-mm incision ECCE/Scl*

None

Yes

NR

NR

NR

NR

NR

NR NR

2 NR

0 NR

NR NR

2 3

40 10

NR NR

NR NR

1

8

NR

2

8

1

†

None None

Yes Yes

NR NR

NR

ECCE/Scl Trab/ECCE/Scl 1 site‡ ECCE/Scl

Acetylcholine

Yes

⫹16.4

1

5

2

0

NR

NR

ECCE/Scl

Carbachol

Yes

⫺0.1

4

0

0

5

22

0.23

NR

Yes

NR

0

0

0

NR

2

25

0.12

NR

Yes

NR

NR

NR

NR

NR

1

151

0.14

NR

Yes

⫺7.4

NR

NR

NR

NR

2

64

0.10

NR

Yes

⫺7.3

NR

NR

NR

NR

Trab/Limbus/ECCE/ None Scl Trab/Fornix/ None ECCE/Scl Trab/Limbus/PECE Acetylcholine 1-site Trab/Fomix/PECE 1 Acetylcholine site

ECCE ⫽ extracapsular cataract extraction; NR ⫽ not reported; PECE ⫽ phacoemulsification cataract extraction; Phaco ⫽ phacoemulsification; Scl ⫽ scleral; Trab ⫽ trabeculectomy. * Glaucoma patients. † ‡

Nonglaucoma patients. Glaucoma suspect.

going PECE (71 eyes). All patients received levobunolol at the end of the case. One small retrospective study (quality score, 30%) compared intracameral acetylcholine (8 eyes) to intracameral carbachol (8 eyes) at the end of ECCE in glaucoma patients and found that IOP increased by a mean of 16.4 mmHg in the acetylcholine group, whereas it decreased by a mean of 0.1 mmHg in the carbachol group.6 No large case series reported on short-term IOP results in glaucoma patients undergoing ECCE. A study looking at adding a glaucoma procedure to ECCE reported a mean short-term IOP rise of 10.2 mmHg for glaucoma patients undergoing ECCE alone (80 eyes).7

The Evidence-based Practice Center (EPC) team concluded that: (1) data were insufficient to determine the impact of PECE on short-term IOP control [evidence grade, I], and (2) ECCE alone in glaucoma patients increases short-term IOP on the first postoperative day [evidence grade, C]. Question 2: What Is the Effect of Combined Cataract and Glaucoma Operations on Short-term Intraocular Pressure Control? Two studies (quality scores of 48%8 and 64%9) reported the results of PECE with a glaucoma procedure on short-term IOP control among glaucoma patients. Lyle and Jin9 compared 3-mm (104 eyes) versus 6-mm (112 eyes) incisions in PECE plus trabeculectomy cases and found similar declines in IOP on postoper-

1905

Ophthalmology Volume 109, Number 10, October 2002 Table 3. What Is the Effect of Cataract Surgery (with or without Other Procedures or Treatments) on Long-term Intraocular Pressure Control in Open-angle Glaucoma Patients? Outcomes and Benefits of Surgery Study Information (Author, Year; Location; Mean Follow-up; Quality Score)

Number Proportion Study of Eyes of Black Group Enrolled Patients

Study design: Randomized controlled trials Anders et al33 1 43 Europe, 1997 Follow-up, 12–23 mos 2 42 Quality, 67% 35 Bobrow 1 35 USA, 1998 Follow-up, ⱖ24 mos 2 35 Quality, 82% 30 El-Sayyad et al 1 53 Saudi Arabia, 1999 Follow-up, not reported 2 53 Quality, not applicable 13 Gimbel et al 1 53 Canada, 1995 Follow-up, 12–23 mos 2 53 Quality, 63% 12 Storr-Paulsen et al 1 10 Europe, 1998 Follow-up, 6–11 mos 2 10 Quality, 72% Study design: Nonrandomized controlled trials Shingleton et al47 1 44 USA, 1999 Follow-up, not reported 2 44 Quality, 63% Study design: Cohort studies Bellucci et al36 1 100 Europe, 1997 Follow-up, not reported 2 200 Quality, 21% Caprioli et al37 1 40 USA, 1996 Follow-up, 12–23 mos 2 40 Quality, 83% Derick et al38 1 42 USA, 1998 Follow-up, 12–23 mos 2 42 Quality, 63% Hayashi et al14 1 77 Asia (Japan), 2000 Follow-up, 12–23 mos 2 73 Quality, 50% 3 74 Lyle and Jin9 1 104 USA, 1991 Follow-up, 12–23 mos Quality, 64% 2 112 Manoj et al41 Europe, 2000 Follow-up, ⱖ24 mos Quality, 33% McGuigan et al7 USA, 1986 Follow-up, 12–23 mos Quality, 40% Naveh et al39 Israel, 1990 Follow-up, 12–23 mos Quality, 48%

Number of Eyes at Reported Follow-up

Surgical Interventions

42

⫺7.7

NR

0.12

NR

Filter (radial incision), PECE/Scl, 1 site PECE/Scl

41

⫺3.7

NR

1.00

0.14

Trab/ECCE/Scl

35

⫺8.2

NR

0.17

0.14

ECCE/Scl

35

⫺4.3

NR

0.77

0.25

PECE/Scl/clear cornea

53

⫺13.8

NR

NR

0.25

PECE/Scl, 1 site

53

⫺14.7

NR

NR

NR

Trab/PECE/Scl

51

⫺6.1

NR

NR

NR

PECE/Scl

51

⫺3.8

NR

NR

NR

Trab/PECE/Scl

10

NR

NR

0.00

NR

PECE/Scl

10

NR

NR

1.00

0.00

Trab/Limbus/PECE/Scl, 1 site

44

⫺6.1

NR

0.16

0.00

Trab/Fornix/PECE/Scl, 1 site

44

⫺6.1

NR

0.20

NR

Trab/no CE

75

⫺11.2

NR

0.47

NR

Trab/PECE/Scl, 1 site

118

⫺3.1

NR

0.16

0.08

Trab/PECE, 2 site

39

⫺6.8

NR

0.50

0.00

Trab/no CE

40

⫺10.3

NR

0.40

0.11

Trab/PECE/Scl

Can’t tell

⫺8.9

26

0.38

0.12

Trab no CE

Can’t tell

⫺10.6

32

0.50

NR

PECE*, clear cornea

Can’t tell

⫺6.4

NR

NR

NR NR NR

PECE , clear cornea PECE/Scl‡ Trab/PECE, 1 site, 3-mm incision

Can’t tell Can’t tell 104

⫺4.1 ⫺1.0 ⫺8.9

NR NR NR

NR NR 0.20

NR

⫺6.8

NR

0.40

Can’t tell

⫹0.3

NR

NR

Can’t tell

⫺0.6

NR

NR

Can’t tell

NR

NR

1.14

NR

†

1

34

NR

Trab/PECE, 1 site, 6-mm incision ECCE, clear cornea

2

21

NR

PECE, clear cornea

1

40

Mean No. Eyes with Intraocular 30% Reduction Mean Pressure Intraocular No. Change Pressure Medications

NR

§

ECCE/Fornix/Scl 㛳

112

2 3 1

40 10 40

NR NR NR

ECCE/Scl ¶ ECCE/Scl 1 site Trab/ECCE/Scl

Can’t tell Can’t tell Can’t tell

NR NR ⫺9.2

NR NR NR

1.00 NR 2.31

2

38

NR

Trab, no CE

Can’t tell

⫺15.8

NR

0.55 (continues)

1906

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma Table 3. (continued) Outcomes and Benefits of Surgery Study Information (Author, Year; Location; Mean Follow-up; Quality Score) Neumann et al32 Israel, 1988 Follow-up, 6–11 mos Quality, 34% Shingleton et al5 USA, 1999 Follow-up, not reported Quality, 59% Tezel et al25 USA, 1997 Follow-up, 12–23 mos Quality, 48% Tezel et al8 USA, 1997 Follow-up, 12–23 mos Quality, 40% Yalvac et al34 Europe, 1997 Follow-up, not reported Quality, 48% Yu et al40 Europe, 1996 Follow-up, 12–23 mos Quality, 65% Study design: Clinical series McCartney et al31 USA, 1988 Follow-up, not reported Quality, not applicable Onali and Raitta18 Europe, 1991 Follow-up, ⱖ24 mos Quality, not applicable Perasalo15 Europe, 1997 Follow-up, not reported Quality, not applicable Yang et al23 USA, 1997 Follow-up, 12–23 mos Quality, not applicable Bloomberg24 USA, 1996 Follow-up, ⱖ24 mos Quality, not applicable Burratto and Ferrari42 Europe, 1990 Follow-up, 6–11 mos Quality, not applicable Calissendorf and HambergNystrom16 Europe, 1992 Follow-up, ⱖ24 mos Quality, not applicable Chen et al43 USA, 1998 Follow-up, 12–23 mos Quality, not applicable

Surgical Interventions

Number of Eyes at Reported Follow-up

1

23

NR

Trab/ECCE/Scl/IOL

Can’t tell

⫺6.3

NR

NR

2

23

NR

Trab/ECCE/Scl, no IOL

Can’t tell

⫺6.5

NR

NR

1

164

NR

PECE*, clear cornea

164

⫺2.1

NR

0.00

2 3 1

75 71 127

NR NR 0.13

PECE¶, clear cornea PECE§, clear cornea ECCE, 1 site

75 71 127

⫺1.9 ⫺1.1 ⫺7.70

NR NR NR

0.00 0.65 1.90

2

270

0.13

Phaco, 1 site

270

⫺5.70

NR

0.70

1

151

0.14

Trab/Limbus/PECE, 1 site

151

⫺8.1

NR

NR

2

64

0.10

Trab/Fornix/PECE, 1 site

64

⫺8.1

NR

NR

1

35

NR

PECE/Scl

35

⫺3.4

NR

1.00

2

21

NR

Trab/PECE/Scl, 1 site

21

⫺6.8

NR

1.00

1

21

0.00

ECCE, 2 site

21

⫺7.5

NR

0.57

2

24

0.00

Trab, no CE

24

⫺11.4

NR

0.35

1

108

NR

Trab/ECCE/Scl

102#

⫺6.2

NR

0.48

1

103

NR

ECCE/Scl

72

⫺1.5

NR

NR

1

226

NR

PECE/Scl

127

⫺1.8

NR

0.90

1

182

0.12

Trab/PECE/Scl, 1 site

175

⫺7.4

NR

0.30

1

NR

NR

PECE, 1 site

53

⫺5.1

NR

0.20

1

104

NR

PECE/Scl

104

0.0

NR

NR

1

113

NR

ECCE/Scl

74

⫺2.6

NR

0.68

1

115

0.15

PECE/ECCE/Scl, clear cornea

Can’t tell

2.4

NR

NR

Number Proportion Study of Eyes of Black Group Enrolled Patients

Mean No. Eyes with Intraocular 30% Reduction Mean Pressure Intraocular No. of Change Pressure Medications

(continues)

1907

Ophthalmology Volume 109, Number 10, October 2002 Table 3. (continued) Outcomes and Benefits of Surgery Study Information (Author, Year; Location; Mean Follow-up; Quality Score) Cinotti et al17 USA, 1998 Follow-up, 12–23 mos Quality, not applicable Crandall21 USA, 1991 Follow-up, 12–23 mos Quality, not applicable Gunning and Greve20 Europe, 1991 Follow-up, 12–23 mos Quality, not applicable Jayamanne et al22 Europe, 1997 Follow-up, 6–11 mos Quality, not applicable Kooner et al19 USA, 1988 Follow-up, not reported Quality, not applicable

Number Proportion Study of Eyes of Black Group Enrolled Patients

Surgical Interventions

Number of Eyes at Reported Follow-up

Mean No. Eyes with Intraocular 30% Reduction Mean Pressure Intraocular No. of Change Pressure Medications

1

160

NR

ECCE/Scl

116

⫺1.4

NR

1.00

1

100

0.02

Trab/PECE, 1 site

Can’t tell

NR

NR

NR

1

102

NR

ECCE, clear cornea

102

⫺5.2

NR

0.59

1

100

NR

Trab/PECE/Scl, 1 site

Can’t tell

⫺7.6

NR

0.10

1

91

NR

ECCE/Scl

64

⫺2.2

NR

NR

2

9

NR

9

0.0

NR

NR

3

3

NR

Previous trab/ECCE, clear cornea Trab/ECCE/Scl

3

⫺2.7

NR

NR

CE ⫽ cataract extraction; ECCE ⫽ extracapsular cataract extraction; IOL ⫽ intraocular lens; NR ⫽ not reported; PECE ⫽ phacoemulsification cataract extraction; Phaco ⫽ phacoemulsification; Scl ⫽ scleral; Trab ⫽ trabeculectomy. * Angle-closure glaucoma patients. †

Open-angle glaucoma patients. Controls. § Glaucoma patients. 储 Nonglaucoma patients. ¶ Glaucoma suspects. ** Normal subjects without glaucoma. # Last follow-up IOP was reported at 1.5 years; last follow-up glaucoma medications at 1 year. ‡

ative day 1 (mean decrease of 7.8 mmHg versus 9.9 mmHg). Tezel et al8 compared limbus-based (151 eyes) versus fornix-based (64 eyes) flaps in PECE plus trabeculectomy and found a similar immediate decrease in IOP (mean decrease of 7.4 mmHg versus 7.3 mmHg). Three additional articles (with quality scores of 40%,7 54%,10 and 67%11) addressed the impact of ECCE with a glaucoma procedure on short-term IOP control. McGuigan et al7 reported that 9 of 10 patients undergoing a combined ECCE and trabeculectomy had an IOP less than 10 mmHg on the first postoperative day. In a study comparing limbus-based (22 eyes) with fornix-based combined procedures (25 eyes), Murchison and Shields11 found that a slightly higher proportion undergoing the limbus-based procedure had a decrease in short-term IOP (100% versus 76%). Krupin et al10 used an unusual randomization scheme. Individuals with controlled glaucoma were randomized to ECCE or ECCE plus trabeculectomy. Those with uncontrolled glaucoma were assigned to ECCE plus trabeculectomy or ECCE plus trabeculotomy. Ultimately, 26 eyes were randomized to ECCE, 33 to ECCE plus trabeculectomy, and nine eyes to ECCE plus trabeculotomy. The analysis combined the ECCE plus glaucoma surgery groups even though the trabeculotomy results were not as good as those with

1908

trabeculectomy. The ECCE plus glaucoma surgery groups had a mean decrease of 6.1 mmHg in IOP (for the combined group), with 12 of 42 showing an increase in IOP on postoperative day 1. The EPC team concluded that: (1) PECE combined with a glaucoma procedure results in IOP decreases at 1 day after surgery [evidence grade, C], and (2) ECCE combined with a glaucoma procedure results in lower IOP on the first postoperative day [evidence grade, C]. Question 3: Do Combined Cataract and Glaucoma Operations Lower Short-term Intraocular Pressure More Than Cataract Surgery Alone in Glaucoma Patients? Three randomized trials compared cataract extraction with cataract extraction plus a glaucoma procedure (quality scores of 54%,10 72%,12 63%13). The study by Krupin et al10 described above found that ECCE alone resulted in a 15.3-mmHg average increase in IOP, with 22 of 26 eyes showing an increase in IOP on postoperative day 1. In contrast, ECCE plus a glaucoma procedure (either trabeculectomy or trabeculotomy) resulted in a mean decrease of 6.1 mmHg in IOP, with 12 of 42 eyes showing an increase in IOP on postoperative day 1. A second study by Storr-Paulsen et al12 compared PECE with PECE plus trabeculectomy, but only randomizing 10 eyes to each

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma group. Timolol was used at the end of surgery, and acetazolamide was given 6 hours after surgery. The median IOP decreased from 23 mmHg to 20.5 mmHg in the PECE group (postoperative IOP range, 0 –32 mmHg) as compared with a decrease from 20 to 8 mmHg (postoperative IOP range, 0 –35 mmHg) in the PECE plus trabeculectomy group. The third study, by Gimbel et al,13 compared PECE with PECE plus trabeculotomy. The authors did not report using any ocular hypotensive at the end of the case. The results at 1 day were similar between the two groups, with a mean decrease in IOP of 2.0 mmHg in the PECE arm and 2.2 mmHg in the PECE plus trabeculotomy arm. The results were reported on 51 patients in each group, even though 53 were randomized per group. The EPC team concluded that there were insufficient data to determine whether short-term IOP control is significantly better with a combined cataract and glaucoma operation than with cataract surgery alone [evidence grade, I].

Long-term Intraocular Pressure Control (More Than 24 Hours) Question 1: What Is the Long-term Intraocular Pressure-lowering Effect of Cataract Extraction Alone in Glaucoma Patients? We found no randomized controlled trials (RCTs) or cohort studies addressing this question. However, several studies reported on the IOP-lowering effect of cataract extraction alone in glaucoma patients. Three case series reported the IOP-lowering effect of PECE on patients with glaucoma.5,14,15 Hayashi et al14 reported results separately for Japanese individuals with angle-closure glaucoma (ACG; 77 eyes) and open-angle glaucoma (OAG; 73 eyes).14 At 12 months, the average IOP decreased by 6.4 mmHg in the ACG group and 4.1 mmHg in the OAG group. The second case series reported on glaucoma suspects (75 eyes) and individuals with glaucoma (71 eyes).5 At 1 year, IOP decreased a mean of 1.9 mmHg in the suspects and 1.1 mmHg in those with glaucoma, with glaucoma patients requiring fewer medications than at baseline. The third case series reported on 127 eyes followed up for 1 year and found a mean decrease in IOP of 1.8 mmHg.15 Six case series reported on the IOP-lowering effect of ECCE alone in glaucoma patients.7,16 –20 The first article reported that all 40 subjects undergoing ECCE had IOP less than 24 mmHg before surgery. At an average follow-up of 18 months, 19 eyes were using the same number of medications, 11 required additional medications, and 10 required fewer medications.7 The second case series reported on 74 subjects followed up for 3 years.16 The mean decrease in IOP among 11 ocular hypertensives (who had higher baseline IOP) was 5.5 mmHg, whereas among 63 glaucoma patients, it was 2.1 mmHg. The third case series reported on 160 glaucoma patients undergoing ECCE with a mean follow-up of 1 year and found a mean decrease in IOP of 1.4 mmHg.17 Medication requirements did not change. The fourth case series reported on 37 patients with OAG and 66 with pseudoexfoliation glaucoma with a mean follow-up of more than 2 years.18 Intraocular pressure declines were similar in the two groups, with a mean decrease of 1.5 mmHg. Another case series reported on 91 ECCE cases in glaucoma patients without prior trabeculectomy.19 With a mean follow-up of 18 months, IOP decreased an average of 2.2 mmHg in the ECCE alone group; 81% were using the same number, 13% were using more, and 8% were using fewer medications. The final case series included ACG and OAG subjects requiring cataract extraction, as well as those with previous filters.20 Although overall mean IOP lowering was 5.2 mmHg, the ACG group declined 7.3 mmHg, whereas the OAG group dropped 2.6 mmHg. The EPC team concluded that although no studies included an untreated control group, the evidence was consistent that cataract extraction (both PECE and ECCE) decreased the IOP of glaucoma

patients by an average of 2 to 4 mmHg at 1 to 2 years after surgery [evidence grade, C]. Question 2: What Is the Long-term Intraocular Pressurelowering Effect of Cataract Extraction and Trabeculectomy? Seven studies reported on the results of PECE plus trabeculectomy.9,21–29 Crandall21 did not report long-term IOP results, but found that 4 of 100 eyes (98 from white persons) required subsequent IOP-lowering surgery. Jayamanne et al22 followed up 100 eyes for a mean of 11 months and found that 96% had an IOP less than 21 mmHg, with a mean decrease in IOP of 7.6 mmHg. Yang et al23 reported on 182 eyes (12% of subjects were black), all of whom received mitomycin C, with a mean follow-up of 17 months. The mean IOP decrease was 7.4 mmHg, and 95% achieved an IOP of 21 mmHg or less. The last case series used a no-stitch trabeculectomy combined with a trabeculotomy along with PECE and reported a mean decrease in IOP of 7.71 ⫾ 1.2 mmHg at 2 years.24 Four additional studies (quality scores of 64%,9 48%,8 40%,25 and 61%30) reported on combined PECE and trabeculectomy cases.8,9,25,30 Lyle and Jin9 reported a 7-mmHg decrease in over 200 combined cases using either a small incision with a foldable intraocular lens or a larger incision with a polymethylmethacrylate lens. Tezel et al8 reported an 8-mmHg decrease in IOP with combined surgery using either a limbus-based or fornix-based conjunctival flap. The same author reported a 7.7-mmHg decrease in IOP in 270 PECE plus trabeculectomy cases in a study comparing combined PECE with combined ECCE surgery.25 ElSayyad et al30 reported an average decrease of approximately 14 mmHg in more than 100 patients undergoing PECE plus trabeculectomy using either a one- or two-site approach. In addition to the studies of PECE cited above, three studies reported on the results of ECCE plus trabeculectomy. McCartney et al31 reported on a mix of 102 OAG and ACG subjects followed up for a mean of 17 months.31 The IOP decreased an average of 6.2 mmHg, and medication requirements declined as well, with 40% taking two or more drops before surgery and only 8% taking as much after surgery. Neumann et al32 (quality score, 34%) compared ECCE plus trabeculectomy with and without intraocular lens implantation and reported a mean IOP decline of 6.3 ⫾ 1.0 mmHg in the group with an intraocular lens (23 eyes) followed up for an average of 11 months. Tezel et al25 reported on 127 combined ECCE plus trabeculectomy patients with a mean decrease in IOP of 7.7 mmHg. The EPC team concluded that: (1) PECE plus trabeculectomy decreased IOP by approximately 8 mmHg in individuals followed up for 1 to 2 years [evidence grade, C], and (2) ECCE and trabeculectomy combined decreased IOP by 6 to 8 mmHg in subjects followed up for 1 to 2 years [evidence grade, C]. Question 3: Is Long-term Intraocular Pressure Control Better with Combined Cataract and Glaucoma Surgery Than Cataract Surgery Alone? There were three randomized trials of good study quality (67%,33 63%,13 and 72%12) comparing long-term IOP control in individuals with glaucoma undergoing PECE with those undergoing PECE combined with other glaucoma procedures. Anders et al33 compared a “no-stitch” technique using a radial incision in the base of the scleral tunnel with a scleral PECE approach. At 1 year, the PECE only group had a mean reduction in IOP of 3.7 ⫾ 4.2 mmHg, with an average decrease of 0.5 medications. The combined group had a larger mean decrease in IOP (7.7 ⫾ 5.5 mmHg; P ⬍ 0.001) and on average required 1.5 fewer medications than at baseline. Twenty-eight of 42 individuals in the PECE group still required medication at 1 year versus eight of 43 in the combined group. Storr-Paulsen et al12 compared PECE with PECE plus trabeculectomy, but only randomizing 10 eyes to each group. The median IOP decreased from 23 to 16.5 mmHg in the PECE group (postoperative IOP range, 12–18 mmHg) as com-

1909

Ophthalmology Volume 109, Number 10, October 2002 pared with a decrease from a median IOP of 20 to 13 mmHg (postoperative IOP range, 12–21 mmHg) in the PECE plus trabeculectomy group. A study by Gimbel et al13 compared PECE with PECE plus trabeculotomy. At 24 months, the mean decrease in the phacoemulsification alone group was 3.8 mmHg versus 6.1 mmHg (P ⫽ 0.001) in the combined group, but the phacoemulsification alone group was using fewer ocular hypotensive medications (mean, 0.4 versus 1.4). The results were reported for 51 patients in each group, even though 53 were randomized per group. One nonrandomized study (quality score, 46%) retrospectively reviewed the charts of 21 glaucoma patients undergoing combined PECE surgery and trabeculectomy and compared the results with those of 35 eyes of glaucoma patients who underwent PECE alone.34 IOP decreased a mean of 3.4 ⫾ 4.0 mmHg in the PECE alone group, as compared with 6.8 ⫾ 7.4 mmHg in the combined group at 6 months, with no difference in the number of ocular hypotensive medications being used. One randomized study reported on glaucoma patients undergoing ECCE (quality score, 82%).35 Thirty-five patients were allocated randomly to ECCE alone in one eye and ECCE plus trabeculectomy in the fellow eye (followed up for an average of 87 months). Eyes randomized to combined procedures had a mean reduction in IOP of 8.2 ⫾ 4.6 mmHg versus 4.3 ⫾ 3.3 mmHg in the ECCE alone group (P ⬍ 0.001). After surgery, individuals in the combined group were taking an average of 0.17 medications versus 0.77 in the ECCE alone arm. No patient required additional surgical procedures to control eye pressure. The EPC team concluded that long-term IOP control is significantly better with combined glaucoma and cataract procedures (PECE and ECCE) than with cataract extraction alone [evidence grade, A]. Question 4: Does Combined Cataract and Glaucoma Surgery in Glaucoma Patients Lower Intraocular Pressure as Much as Trabeculectomy Alone in the Long-term? Three nonrandomized studies (quality scores of 21%,36 83%,37 and 63%38) compared IOP results using PECE plus trabeculectomy with trabeculectomy alone. Bellucci et al36 compared 100 trabeculectomies with 200 combined PECE plus trabeculectomies and found that trabeculectomy alone resulted in a larger mean decrease in IOP than the combined procedure (11.2 mmHg versus 3.1 mmHg; P ⬍ 0.01). However, the mean initial IOP was much higher in the trabeculectomy alone group (26.4 mmHg versus 21.8 mmHg). A cohort study by Caprioli et al37 compared 40 cases of PECE plus trabeculectomy (two site) with trabeculectomy alone. These authors reported that mean IOP decreased more in the trabeculectomy alone group (10.3 ⫾ 7.6 mmHg versus 6.8 ⫾ 5.5 mmHg), and that a higher proportion achieved the target pressure in the trabeculectomy alone group (88% versus 72%). Derick et al38 reported a slightly larger mean decrease in IOP in the trabeculectomy alone group (10.6 mmHg versus 8.9 mmHg; no P value reported), with similar medication requirements (42 eyes in each group). Two cohort studies (quality scores, 48%39 and 65%40) compared ECCE plus trabeculectomy with trabeculectomy alone. Naveh et al39 reported that mean IOP decreased by 9.2 ⫾ 4.2 mmHg in the combined group (27 eyes) compared with 15.8 ⫾ 3.9 mmHg in the trabeculectomy alone group (29 eyes) at 24 months. At follow-up, the combined group also required an average of 2.1 medications versus 0.5 in the trabeculectomy alone group (P ⬍ 0.001). Yu et al40 also reported greater IOP lowering with trabeculectomy alone (mean, 11.4 mmHg in 24 eyes) than with a combined procedure (mean, 7.5 mmHg in 21 eyes; P ⬎ 0.05), with similar medication use in the two groups.40 The EPC team concluded that: (1) trabeculectomy alone lowers long-term IOP slightly more than combined PECE and trabeculectomy [evidence grade, C], and (2) trabeculectomy alone lowers

1910

long-term IOP more than combined ECCE and trabeculectomy [evidence grade, B]. Question 5: Does Cataract Extraction in Patients with Functioning Filtering Blebs Negatively Impact Long-term Intraocular Pressure Control in Patients with Glaucoma? Five articles looked at the effect of cataract extraction on IOP in patients with preexisting filtering blebs.20,37,41– 43 Quality scores were determined for two of the five articles (83%37 and 33%41). Caprioli et al37 reported results of a survival analysis in a matched casecontrol study comparing individuals with existing blebs (40 eyes) with those with existing blebs undergoing clear cornea PECE (40 eyes) and found no difference in IOP control over time. In contrast, Chen et al43 reported on 115 eyes in a retrospective review of patients with functioning filtering blebs in whom either ECCE (58 eyes) or PECE (57 eyes) was performed using both clear corneal and scleral approaches. For the group as a whole, 30.4% required either additional medication or bleb needling to maintain IOP control at a mean follow-up of 21 months. An additional 11 eyes (9.6%) required glaucoma surgery. A Cox proportional hazards model found the relative hazard of requiring glaucoma surgery was 3.0 (95% confidence interval, 0.7, 12.8) for those undergoing ECCE as compared with PECE. No control group was enrolled to assess the baseline rate of bleb failure in this population. Manoj et al41 compared ECCE with PECE in patients with preexisting filtering blebs. Intraocular pressure increased significantly (mean increase, 1.9 mmHg) in the ECCE group (34 eyes), but remained unchanged in the PECE group (21 eyes). Medication requirements were also greater in the ECCE group. Gunning and Greve20 reported a mean decrease of 1.5 mmHg (not statistically significant) in individuals undergoing ECCE with preexisting filters. Finally, Burratto and Ferrari42 studied 102 individuals undergoing either ECCE or PECE with preexisting blebs. Although the data presented were limited, it appeared that the IOP was similar to baseline 8 months after cataract surgery. The EPC team concluded that although four of five studies documented no effect of cataract extraction on bleb function, the fifth study had a high rate of bleb failure. The data are inconclusive as to whether cataract extraction negatively impacts preexisting filtering blebs [evidence grade, I].

Discussion Our systematic review of the literature regarding the shortand long-term control of IOP after surgical management of patients with coexisting cataract and glaucoma offers important insights into the state of knowledge regarding the optimal treatment of these individuals. Table 4 summarizes the evidence in support of the major findings. The current report has potential limitations. Although effort was made to include multiple sources in the literature search, including electronic databases and hand searching, this report may be open to publication bias. For example, because of practical resource issues, we limited our review to articles written in English. Potentially relevant studies thus may have been omitted, introducing the potential for bias.44 – 46 For instance, Egger et al44 found that German researchers were more likely to publish significant results in English-language journals and negative results in Germanlanguage journals. Future analyses would benefit from a search of the non-English language literature. The literature provides weak but consistent evidence that cataract surgery alone lowers long-term IOP by several millimeters of mercury using either PECE or ECCE. Direct

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma Table 4. Summary of the Evidence on Intraocular Pressure Control with Surgical Treatment of Coexisting Cataract and Glaucoma on Long-term Intraocular Pressure Control Good evidence: ● Long-term IOP control is greater with combined procedures than with cataract extraction alone. Fair evidence ● Trabeculectomy alone lowers long-term IOP more than combined ECCE and trabeculectomy. Weak evidence ● Cataract extraction in glaucoma patients lowers IOP on average by 2 to 4 mmHg. ● Trabeculectomy alone appears to lower IOP more than combined PECE and trabeculectomy. ● PECE and trabeculectomy lowers IOP by approximately 8 mmHg in individuals followed up for a mean of 1 to 2 years. ● ECCE and trabeculectomy lowers IOP by approximately 6 to 8 mmHg in individuals followed up for a mean of 1 to 2 years. Insufficient evidence ● The evidence was insufficient to determine the impact of cataract extraction on preexisting filtering blebs. ● The evidence was insufficient to determine if other combined techniques (e.g., cyclodialysis and endolaser) work as well as cataract extraction and trabeculectomy. ● The evidence was insufficient to determine if combined PECE and trabeculectomy lowers IOP on the first postoperative day more than PECE alone. ECCE ⫽ extracapsular cataract extraction; IOP ⫽ intraocular pressure; PECE ⫽ phacoemulsification cataract extraction.

comparison of the two techniques provides weak support that PECE results in slightly greater long-term IOP lowering than ECCE, with perhaps an even greater IOP-lowering effect in individuals with ACG. No studies addressing this question included a control group of unoperated glaucoma subjects. This lack of controls raises the possibility that long-term IOP decreased after cataract extraction for reasons unrelated to the procedures used (for example, new medications may have been approved for clinical use). However, given the consistency of the findings in the literature and the high probability that the natural tendency of the IOP in glaucoma patients is to increase over time, we believe that the effect is real. The literature provides little information about immediate postoperative IOP spikes in glaucoma patients undergoing cataract surgery alone. One early study reported high rates of large IOP spikes in glaucoma subjects undergoing ECCE procedures.7 Another article comparing intracameral acetylcholine with intracameral carbachol also reported large IOP elevations in glaucoma patients undergoing ECCE receiving acetylcholine.6 This second article found that the use of carbachol prevented the pressure rise. Unfortunately, data regarding the ability of pharmacologic agents to blunt IOP elevations reported after ECCE in glaucoma patients are limited. Even less has been published on the short-term impact of PECE on IOP in patients with glaucoma. The few publications on this topic indicate that IOP on average decreases on the first postoperative day. This gap in the literature is important because one motivating factor in deciding to perform a combined procedure is the desire to prevent

postoperative IOP elevations. If this risk were known to be small with PECE (or with PECE and appropriate intraoperative and postoperative medications), it would not serve as an indication for performing combined procedures. The literature provides good evidence that long-term IOP is lowered more by combined glaucoma and cataract procedures than by cataract extraction alone. There is weak to moderate evidence that combined procedures are not as effective at lowering IOP as trabeculectomy alone, however. Adding a cataract operation to a planned trabeculectomy appears to diminish the IOP-lowering effect of trabeculectomy by approximately 2 to 4 mmHg on average. The implication is that when IOP is of paramount importance, it may be better to separate the cataract and trabeculectomy procedures. Finally, although the data are inconclusive, one well-designed case-control study found no difference in bleb survival after clear cornea PECE.37 This suggests that cataracts can be removed without jeopardizing IOP control in patients with established filtering blebs. If future studies corroborate these findings, it would strengthen further the case for performing a trabeculectomy alone in cases where IOP lowering is the primary objective. Alternatively, in clinical situations in which IOP lowering may be beneficial, but large decreases in IOP are not required, cataract extraction alone may be adequate to the task. Studies of both PECE and ECCE alone consistently found them to lower long-term IOP by a few millimeters of mercury. Although the literature would benefit from a study comparing long-term IOP control in glaucoma patients undergoing PECE and ECCE alone with those having no surgical intervention, the weight of the evidence argues that cataract extraction does indeed lower long-term IOP. The available observations suggest that this IOP-lowering effect may be even larger in patients with ACG. None of the publications identified addressed the important clinical issue of the impact of clear cornea cataract extraction on success rates of subsequent trabeculectomy. This information would be valuable in helping clinicians determine the best algorithm for treating patients with coexisting cataract and glaucoma. In conclusion, the strongest evidence of efficacy is for better long-term control of IOP with combined glaucoma and cataract operations compared with cataract surgery alone. Otherwise the evidence is relatively weak regarding short-term and long-term control of IOP with different surgical treatment strategies for cataract and glaucoma. More research is needed to aid clinicians in choosing among the various treatment options.

References 1. Jampel HD, Lubomski LH, Friedman DS, et al. Treatment of Coexisting Cataract and Glaucoma. Baltimore: EvidenceBased Practice Center, Johns Hopkins University, 6 Oct 2000. Contract No. 290-097-0006, Task Order 3. 2. Justice AC, Cho MK, Winker MA, et al. Does masking author identity improve peer review quality? A randomized controlled trial. PEER Investigators [published erratum appears in JAMA 1998;280:968]. JAMA 1998;280:240 –2.

1911

Ophthalmology Volume 109, Number 10, October 2002 3. Garbutt JC, West SL, Carey TS, et al. Pharmacological treatment of alcohol dependence: a review of the evidence. JAMA 1999;281:1318 –25. 4. Friedman DS, Bass EB, Lubomski LH, et al. Synthesis of the literature on the effectiveness of regional anesthesia for cataract surgery. Ophthalmology 2001;108:519 –29. 5. Shingleton BJ, Gamell LS, O’Donoghue MW, et al. Longterm changes in intraocular pressure after clear corneal phacoemulsification: normal patients versus glaucoma suspect and glaucoma patients. J Cataract Refract Surg 1999;25:885–90. 6. McKinzie JW, Boggs MB Jr. Comparison of postoperative intraocular pressures after use of Miochol and Miostat. J Cataract Refract Surg 1989;15:185–90. 7. McGuigan LJ, Gottsch J, Stark WJ, et al. Extracapsular cataract extraction and posterior chamber lens implantation in eyes with preexisting glaucoma. Arch Ophthalmol 1986;104: 1301– 8. 8. Tezel G, Kolker AE, Kass MA, Wax MB. Comparative results of combined procedures for glaucoma and cataract: II. Limbus-based versus fornix-based conjunctival flaps. Ophthalmic Surg Lasers 1997;28:551–7. 9. Lyle WA, Jin JC. Comparison of a 3- and 6-mm incision in combined phacoemulsification and trabeculectomy. Am J Ophthalmol 1991;111:189 –96. 10. Krupin T, Feitl ME, Bishop KI. Postoperative intraocular pressure rise in open-angle glaucoma patients after cataract or combined cataract-filtration surgery. Ophthalmology 1989;96: 579 – 84. 11. Murchison JF Jr, Shields MB. Limbal-based vs. fornix-based conjunctival flaps in combined extracapsular cataract surgery and glaucoma filtering procedure. Am J Ophthalmol 1990; 109:709 –15. 12. Storr-Paulsen A, Pedersen JH, Laugesen C. A prospective study of combined phacoemulsification-trabeculectomy versus conventional phacoemulsification in cataract patients with coexisting open angle glaucoma. Acta Ophthalmol Scand 1998;76:696 –9. 13. Gimbel HV, Meyer D, DeBroff BM, et al. Intraocular pressure response to combined phacoemulsification and trabeculotomy ab externo versus phacoemulsification alone in primary openangle glaucoma. J Cataract Refract Surg 1995;21:653– 60. 14. Hayashi K, Hayashi H, Nakao F, Hayashi F. Changes in anterior chamber angle width and depth after intraocular lens implantation in eyes with glaucoma. Ophthalmology 2000; 107:698 –703. 15. Perasalo R. Phaco-emulsification of cataract in eyes with glaucoma. Acta Ophthalmol Scand 1997;75:299 –300. 16. Calissendorff BM, Hamberg-Nystrom H. Pressure control in glaucoma patients after cataract surgery with intraocular lens. Eur J Ophthalmol 1992;2:163– 8. 17. Cinotti DJ, Fiore PM, Maltzman BA, et al. Control of intraocular pressure in glaucomatous eyes after extracapsular cataract extraction with intraocular lens implantation. J Cataract Refract Surg 1988;14:650 –3. 18. Onali T, Raitta C. Extracapsular cataract extraction and posterior chamber lens implantation in controlled open-angle glaucoma [published erratum appears in Ophthalmic Surg 1991;22:695]. Ophthalmic Surg 1991;22:381–7. 19. Kooner KS, Dulaney DD, Zimmerman TJ. Intraocular pressure following ECCE and IOL implantation in patients with glaucoma. Ophthalmic Surg 1988;19:570 –5. 20. Gunning FP, Greve EL. Intercapsular cataract extraction with implantation of the Galand disc lens: a retrospective analysis in patients with and without glaucoma. Ophthalmic Surg 1991;22:531– 8.

1912

21. Crandall AS. Combined trabeculectomy and phacoemulsification. Semin Ophthalmol 1991;6:76 – 80. 22. Jayamanne DG, Kostakis A, Phelan PS. The outcome of 2.3 mm incision combined phacoemulsification, trabeculectomy and lens implantation of non-foldable intraocular lenses. Eye 1997;11:91– 4. 23. Yang KJ, Moster MR, Azuara-Blanco A, et al. Mitomycin-C supplemented trabeculectomy, phacoemulsification, and foldable lens implantation. J Cataract Refract Surg 1997;23: 565–9. 24. Bloomberg LB. Modified trabeculectomy/trabeculotomy with no-stitch cataract surgery. J Cataract Refract Surg 1996;22: 14 –22. 25. Tezel G, Kolker AE, Kass MA, Wax MB. Comparative results of combined procedures for glaucoma and cataract: I. Extracapsular cataract extraction versus phacoemulsification and foldable versus rigid intraocular lenses. Ophthalmic Surg Lasers 1997;28:539 –50. 26. el-Sayyad F, Helal M, el-Maghraby A, et al. One-site versus 2-site phacotrabeculectomy: a randomized study. J Cataract Refract Surg 1999;25:77– 82. 27. Arnold PN. No-stitch phacotrabeculectomy. J Cataract Refract Surg 1996;22:253– 60. 28. Crestani A, De Natale R, Steindler P. Phacotrabeculectomy with or without punch: preliminary results comparing the two techniques. Ophthalmologica 1997;211:72– 4. 29. Nielsen PJ. Combined small-incision cataract surgery and trabeculectomy: a prospective study with 1 year of follow-up. Ophthalmic Surg Lasers 1997;28:21–9. 30. El-Sayyad FF, Helal MH, Khalil MM, El-Maghraby MA. Phacotrabeculectomy versus two-stage operation: a matched study. Ophthalmic Surg Lasers 1999;30:260 –5. 31. McCartney DL, Memmen JE, Stark WJ, et al. The efficacy and safety of combined trabeculectomy, cataract extraction, and intraocular lens implantation. Ophthalmology 1988;95:754 – 63. 32. Neumann R, Zalish M, Oliver M. Effect of intraocular lens implantation on combined extracapsular cataract extraction with trabeculectomy: a comparative study. Br J Ophthalmol 1988;72:741–5. 33. Anders N, Pham T, Holschbach A, Wollensak J. Combined phacoemulsification and filtering surgery with the “no-stitch” technique. Arch Ophthalmol 1997;115:1245–9. 34. Yalvac I, Airaksinen PJ, Tuulonen A. Phacoemulsification with and without trabeculectomy in patients with glaucoma. Ophthalmic Surg Lasers 1997;28:469 –75. 35. Bobrow JC. Cataract extraction and lens implantation with and without trabeculectomy: an intrapatient comparison. Trans Am Ophthalmol Soc 1998;96:521–56. 36. Bellucci R, Perfetti S, Babighian S, et al. Filtration and complications after trabeculectomy and after phaco-trabeculectomy. Acta Ophthalmol Scand Suppl 1997;224:44 –5. 37. Caprioli J, Park HJ, Weitzman M. Temporal corneal phacoemulsification combined with superior trabeculectomy: a controlled study. Trans Am Ophthalmol Soc 1996;94:451– 63; discussion 463– 8. 38. Derick RJ, Evans J, Baker ND. Combined phacoemulsification and trabeculectomy versus trabeculectomy alone: a comparison study using mitomycin-C. Ophthalmic Surg Lasers 1998;29:707–13. 39. Naveh N, Kottass R, Glovinsky J, et al. The long-term effect on intraocular pressure of a procedure combining trabeculectomy and cataract surgery, as compared with trabeculectomy alone. Ophthalmic Surg 1990;21:339 – 45. 40. Yu CB, Chong NH, Caesar RH, et al. Long-term results of combined cataract and glaucoma surgery versus trabeculec-

Friedman et al 䡠 IOP Control after Surgery for Cataract and Glaucoma tomy alone in low-risk patients. J Cataract Refract Surg 1996; 22:352–7. 41. Manoj B, Chako D, Khan MY. Effect of extracapsular cataract extraction and phacoemulsification performed after trabeculectomy on intraocular pressure. J Cataract Refract Surg 2000; 26:75– 8. 42. Burratto L, Ferrari M. Extracapsular cataract surgery and intraocular lens implantation in glaucomatous eyes that had a filtering bleb operation. J Cataract Refract Surg 1990;16: 315–9. 43. Chen PP, Weaver YK, Budenz DL. Trabeculectomy function after cataract extraction. Ophthalmology 1998;105: 1928 –35.

44. Egger M, Zellweger-Zahner T, Schneider M, et al. Language bias in randomised controlled trials published in English and German. Lancet 1997;350:326 –9. 45. Moher D, Fortin P, Jadad AR, et al. Completeness of reporting of trials published in languages other than English: implications for conduct and reporting of systematic reviews. Lancet 1996;347:363– 6. 46. Gregoire G, Derderian F, Le Lorier J. Selecting the language of the publications included in a meta-analysis: is there a Tower of Babel bias? J Clin Epidemiol 1995;48:159 – 63. 47. Phacotrabeculectomy: limbus-based versus fornix-based conjunctival flaps in fellow eyes that appeared in Ophthalmology 1999(106):1152–5.

1913