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Cochrane Database of Systematic Reviews

Cirugía de derivación trabecular ab interno con iStent para el glaucoma de ángulo abierto

Information

DOI:
https://doi.org/10.1002/14651858.CD012743.pub2Copy DOI
Database:
  1. Cochrane Database of Systematic Reviews
Version published:
  1. 28 March 2019see what's new
Type:
  1. Intervention
Stage:
  1. Review
Cochrane Editorial Group:
  1. Cochrane Eyes and Vision Group

Copyright:
  1. Copyright © 2019 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

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Authors

  • Jimmy T Le

    Correspondence to: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA

    [email protected]

  • Amanda K Bicket

    Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, USA

  • Lin Wang

    Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA

  • Tianjing Li

    Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA

Contributions of authors

JL, AB, and TL designed and wrote the review.
JL, LW, and TL screened studies for inclusion.
JL and LW extracted data from studies.
JL, AB, LW, and TL drafted the review and will be responsible for updates.

Sources of support

Internal sources

  • No sources of support supplied

External sources

  • National Eye Institute (NEI), National Institutes of Health (NIH), USA.

    Cochrane Eyes and Vision US Project (and JL during his time with the Project) is supported by cooperative agreement UG1EY020522, NEI, NIH

  • National Institute for Health Research (NIHR), UK.

    • Richard Wormald, Co‐ordinating Editor for Cochrane Eyes and Vision (CEV) acknowledges financial support for his CEV research sessions from the Department of Health through the award made by the National Institute for Health Research to Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology for a Specialist Biomedical Research Centre for Ophthalmology.

    • This review was supported by the National Institute for Health Research, via Cochrane Infrastructure funding to the CEV UK editorial base.

    The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the Systematic Reviews Programme, NIHR, NHS or the Department of Health.

  • National Institute of Aging (NIA), National Institutes of Health (NIH), USA.

    JL is supported by the Epidemiology and Biostatistics of Aging Training Program, Grant Number T32 AG000247 from the NIA, NIH.

Declarations of interest

JL: This Cochrane Review was prepared while Dr. Le was a doctoral candidate at the Johns Hopkins Bloomberg School of Public Health. The opinions expressed in this article are the author's own and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government.
AB: none.
LW: none.
TL: none.

Acknowledgements

We thank Kay Dickersin, Henry Jampel, Gus Gazzard, Barbara Hawkins, Kuang Hu, Riaz Qureshi, Anupa Shah, and Richard Wormald for their comments and suggestions during title registration and preparation of this review. This protocol was adapted from a Cochrane Review assessing the evidence for another minimally invasive glaucoma surgical (MIGS) procedure (Hu 2016). Cochrane Eyes and Vision (CEV) created and executed the electronic search strategies. We thank Anupa Shah for assisting with the review process. We thank Nitin Anand for peer reviewing the protocol and Jennifer Evans for her comments on the protocol. We are grateful to the following peer reviewers for their time and comments on the review: Henry Jampel, Ian Pitha, and Mark Lesselroth.

We thank the members of the MIGS Consortium for their input in this review.

Version history

Published

Title

Stage

Authors

Version

2019 Mar 28

Ab interno trabecular bypass surgery with iStent for open‐angle glaucoma

Review

Jimmy T Le, Amanda K Bicket, Lin Wang, Tianjing Li

https://doi.org/10.1002/14651858.CD012743.pub2

2017 Aug 14

Ab interno trabecular bypass surgery with iStent for open angle glaucoma

Protocol

Jimmy T Le, Amanda K Bicket, Tianjing Li

https://doi.org/10.1002/14651858.CD012743

Differences between protocol and review

The protocol for this review did not specify time windows for the outcomes analyzed. Working with other author teams of the MIGS Consortium, we clarified time windows of interest as short‐term (six months or less), medium‐term (six to 18 months or less), long‐term (greater than 18 months but less than or equal to 36 months), and over 36 months. When conducting meta‐analyses, we used fixed‐effect models in lieu random‐effects models due to small numbers of randomized controlled trials included. Given that the iStent devices were approved in people undergoing cataract surgery (phacoemulsification), we regarded combined phacoemulsification and MIGS procedure versus phacoemulsification alone as a separate comparison instead of a subgroup analysis.

Keywords

MeSH

PICOs

Population
Intervention
Comparison
Outcome

The PICO model is widely used and taught in evidence-based health care as a strategy for formulating questions and search strategies and for characterizing clinical studies or meta-analyses. PICO stands for four different potential components of a clinical question: Patient, Population or Problem; Intervention; Comparison; Outcome.

See more on using PICO in the Cochrane Handbook.

Study flow diagram.
Figures and Tables -
Figure 1

Study flow diagram.

Risk of bias summary: review authors' judgments about each risk of bias item for each included study.
Figures and Tables -
Figure 2

Risk of bias summary: review authors' judgments about each risk of bias item for each included study.

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.1 Proportion of participants who were drop‐free.
Figures and Tables -
Figure 3

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.1 Proportion of participants who were drop‐free.

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.2 Mean change in number of intraocular pressure (IOP)‐lowering drops taken per day from baseline.
Figures and Tables -
Figure 4

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.2 Mean change in number of intraocular pressure (IOP)‐lowering drops taken per day from baseline.

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.3 Mean change in IOP.
Figures and Tables -
Figure 5

Forest plot of comparison: 1 iStent in combination with phacoemulsification versus phacoemulsification alone, outcome: 1.3 Mean change in IOP.

Forest plot of comparison: 3 One iStent (without phacoemulsification) versus two iStents (without phacoemulsification), outcome: 3.1 Proportion of participants who were drop‐free.
Figures and Tables -
Figure 6

Forest plot of comparison: 3 One iStent (without phacoemulsification) versus two iStents (without phacoemulsification), outcome: 3.1 Proportion of participants who were drop‐free.

Forest plot of comparison: 4 One iStent (without phacoemulsification) versus three iStents (without phacoemulsification), outcome: 4.1 Proportion of participants who were drop‐free.
Figures and Tables -
Figure 7

Forest plot of comparison: 4 One iStent (without phacoemulsification) versus three iStents (without phacoemulsification), outcome: 4.1 Proportion of participants who were drop‐free.

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 1 Proportion of participants who were drop‐free.
Figures and Tables -
Analysis 1.1

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 1 Proportion of participants who were drop‐free.

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 2 Mean change in number of intraocular pressure (IOP)‐lowering drops taken per day from baseline.
Figures and Tables -
Analysis 1.2

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 2 Mean change in number of intraocular pressure (IOP)‐lowering drops taken per day from baseline.

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 3 Mean change in IOP.
Figures and Tables -
Analysis 1.3

Comparison 1 iStent in combination with phacoemulsification versus phacoemulsification alone, Outcome 3 Mean change in IOP.

Comparison 2 iStent (or iStent inject) versus medical therapy, Outcome 1 Proportion of participants who were drop‐free.
Figures and Tables -
Analysis 2.1

Comparison 2 iStent (or iStent inject) versus medical therapy, Outcome 1 Proportion of participants who were drop‐free.

Comparison 2 iStent (or iStent inject) versus medical therapy, Outcome 2 Mean change in intraocular pressure.
Figures and Tables -
Analysis 2.2

Comparison 2 iStent (or iStent inject) versus medical therapy, Outcome 2 Mean change in intraocular pressure.

Comparison 3 One iStent versus two iStents, Outcome 1 Proportion of participants who were drop‐free.
Figures and Tables -
Analysis 3.1

Comparison 3 One iStent versus two iStents, Outcome 1 Proportion of participants who were drop‐free.

Comparison 3 One iStent versus two iStents, Outcome 2 Mean change in intraoperative pressure.
Figures and Tables -
Analysis 3.2

Comparison 3 One iStent versus two iStents, Outcome 2 Mean change in intraoperative pressure.

Comparison 4 One iStent versus three iStents, Outcome 1 Proportion of participants who were drop‐free.
Figures and Tables -
Analysis 4.1

Comparison 4 One iStent versus three iStents, Outcome 1 Proportion of participants who were drop‐free.

Comparison 4 One iStent versus three iStents, Outcome 2 Mean change in intraocular pressure.
Figures and Tables -
Analysis 4.2

Comparison 4 One iStent versus three iStents, Outcome 2 Mean change in intraocular pressure.

Summary of findings for the main comparison. IStent in combination with phacoemulsification compared to phacoemulsification alone for open‐angle glaucoma

iStent in combination with phacoemulsification compared to phacoemulsification alone for open‐angle glaucoma

Patient or population: open‐angle glaucoma
Setting:
Intervention: iStent in combination with phacoemulsification
Comparison: phacoemulsification alone

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

№ of participants
(studies)

Certainty of the evidence
(GRADE)

Comments

Risk with phacoemulsification alone

Risk with iStent in combination with phacoemulsification

Proportion of participants who were drop‐free

Follow‐up: range 6 to ≤ 18 months

583 per 1000

804 per 1000
(688 to 950)

RR 1.38
(1.18 to 1.63)

239
(2 RCTs)

⊕⊝⊝⊝
Very lowa,b,c

Estimate based on data from 2 trials.

Mean change in number of IOP‐lowering drops from baseline

Follow‐up: range 6 to ≤ 18 months

The mean change in number of IOP‐lowering drops from baseline ranged from –1.0 to 0.9 drops

MD 0.42 drops fewer
(0.6 fewer to 0.23 fewer)

282
(2 RCTs)

⊕⊝⊝⊝
Very lowa,b,c

In addition, Fernandez‐Barrientos 2010 reported the change in number of IOP‐lowering drops was 0 (SD 0) in the iStent in combination of phacoemulsification treatment group and 0.7 (SD 1) in the phacoemulsification alone group.

Mean change in IOP from baseline

Follow‐up: range 6 to ≤ 18 months

The mean change in IOP from baseline ranged from –8.5 to –1.6 mmHg

MD 1.24 mmHg lower
(3.07 lower to 0.58 higher)

284
(3 RCTs)

⊕⊝⊝⊝
Very lowa,b,c,d

Health‐related quality of life

Not reported in any of the 4 studies.

Intraoperative complications

Samuelson 2011 reported that "[i]n an eye with intraoperative stent malposition, a second stent was implanted during the same surgery."

Postoperative complications

Based on available data, participants who were randomized to treatment with phacoemulsification in combination with iStent were less likely to experience elevated IOP (or IOP spikes) and loss of vision than those randomized to phacoemulsification alone.

334 (4 RCTs)

We did not conduct a meta‐analysis of complications.

Secondary glaucoma surgery

Follow‐up: range 6 to ≤ 18 months

1 participant randomized to treatment with phacoemulsification in combination with iStent and 1 participant randomized to phacoemulsification alone underwent selective laser trabeculoplasty at 12 months.

290 (3 RCTs)

We did not conduct a meta‐analysis of complications.

*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; IOP: intraocular pressure; MD: mean difference; RCT: randomized controlled trial; RR: risk ratio; SD: standard deviation.

GRADE Working Group grades of evidence
High certainty: we are very confident that the true effect lies close to that of the estimate of the effect.
Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect.
Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

aDowngraded one level for high or unclear risk of bias for blinding of outcome assessor.
bDowngraded one level for imprecision due to small sample size/wide confidence interval.
cDowngraded one level for publication bias due to potential for industry influences.
dDowngraded one level for heterogeneity (e.g. I2 > 70%) or inconsistency across trials.

Figures and Tables -
Summary of findings for the main comparison. IStent in combination with phacoemulsification compared to phacoemulsification alone for open‐angle glaucoma
Summary of findings 2. IStent (or iStent inject) compared to medical therapy for open‐angle glaucoma

IStent (or iStent inject) compared to medical therapy for open‐angle glaucoma

Patient or population: open‐angle glaucoma
Setting:
Intervention: iStent (or iStent inject)
Comparison: medical therapy

Outcomes

Anticipated absolute effects* (95% CI)

Relative effect
(95% CI)

№ of participants
(studies)

Certainty of the evidence
(GRADE)

Comments

Risk with medical therapy

Risk with iStent (or iStent inject)

Proportion of participants who were drop‐free

Follow‐up: range 6 to ≤ 18 months

At 12 months, 0/138 participants randomized to medical therapy were drop‐free at 12 months, while 141/148 (95%) participants randomized to treatment with iStent were drop‐free at 12 months. We did not derive an RR because no events occurred in the control groups of either trial.

286
(2 RCTs)

⊕⊝⊝⊝
Very lowa,b,c

In addition, Vold 2016 noted that 48/54 (88%) participants in the iStent treatment group were drop‐free at 36 months.

Mean change in number of IOP‐lowering drops from baseline

Not reported in either study.

Mean change in IOP from baseline

Follow‐up: range 6 to ≤ 18 months

The mean change in IOP from baseline was –11.6 mmHg

MD 0.6 mmHg lower
(1.28 lower to 0.08 higher)

184
(1 RCT)

⊕⊝⊝⊝
Very lowa,b,c

Vold 2016 did not report mean change in IOP but did provide mean IOP (without SD) at 6 months (14.2 mmHg), 18 months (13.5 mmHg), and 36 months (14.6 mmHg) in the iStent treatment groups; and at 6 months (13.8 mmHg), 18 months (14.6 mmHg), and 36 months (15.3 mmHg) in the medical therapy group.

Health‐related quality of life

Not reported in either study.

Intraoperative complications

1 participant in the iStent treatment group experienced hyphema which resolved by day 1

101 (1 RCT)

We did not conduct a meta‐analysis of complications.

Postoperative complications

Vold 2016 noted that best‐corrected visual acuity was stable between both groups and did not report on any other postoperative complications. Fea 2014 reported that 1 participant in the iStent inject group experienced IOP decompensation with an elevated IOP of 48 mmHg.

286
(2 RCTs)

We did not conduct a meta‐analysis of complications.

Secondary glaucoma surgery

Fea 2014 reported that 1 participant needed laser treatment to remove an apparent obstruction

286
(2 RCTs)

We did not conduct a meta‐analysis of complications.

*The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).

CI: confidence interval; IOP: intraocular pressure; MD: mean difference; RCT: randomized controlled trial; RR: risk ratio; SD: standard deviation.

GRADE Working Group grades of evidence
High certainty: we are very confident that the true effect lies close to that of the estimate of the effect.
Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different.
Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect.
Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.

aDowngraded one level for imprecision due to small sample size/wide confidence interval.
bDowngraded one level for high or unclear risk of bias for blinding of outcome assessor.
cDowngraded one level for publication bias due to potential for industry influences.

Figures and Tables -
Summary of findings 2. IStent (or iStent inject) compared to medical therapy for open‐angle glaucoma
Table 1. Eligibility criteria of included studies

Study

Diagnosis

Intraocular pressure

Number of glaucoma medication currently taking

Visual acuity

(Snellen; BCVA)

Prior incisional glaucoma surgery

Prior laser surgery

Washout period

Comparison 1: iStent in combination with phacoemulsification vs phacoemulsification alone

Fea 2010

OAG in need of cataract surgery

> 18 mmHg (medicated)

≥ 1

20/80 or worse

Excluded

NR

NR

Fernandez‐Barrientos 2010

OHT or OAG in need of cataract surgery

> 17 mmHg and < 31 mmHg (medicated); > 21 mmHg and < 36 mmHg (unmedicated)

≤ 2

20/40 or worse

Excluded

Excluded

Yes

NCT00721968

OAG in need of cataract surgery

NR

NR

NR

NR

NR

NR

Samuelson 2011

OAG, PEXG, or PG, in need of cataract surgery

≤ 24 mmHg (medicated); ≥ 22 mmHg and ≤ 36 mmHg (unmedicated)

≥ 1 and ≤ 3

20/40 or worse

Excluded (except for iridectomy)

Excluded

Yes

Comparison 2: iStent or iStent inject vs medical therapy

Fea 2014

OAG, PEXG, or PG

≥ 22 mmHg and < 38 mmHg (unmedicated)

1

20/200 or better

Excluded

Includeda

Yes

Vold 2016

OHT, OAG, or PEXG

≥ 21 mmHg and ≤ 40 mmHg (unmedicated)

0

NR

Excluded

Excluded

NA

Additional comparison: 1 iStent vs 2 iStents vs 3 iStents

Katz 2015

OAG, PEXG, or PG; and phakic

≥ 18 mmHg and ≤ 30 mmHg (medicated); > 22 mmHg and < 38 mmHg (unmedicated)

2

20/200 or better

Excluded

Includeda

Yes

aAs long as the procedure was not performed within 30 days prior to screening.
BCVA: best‐corrected visual acuity; OAG: open‐angle glaucoma; OHT: ocular hypertension; PEXG: pseudoexfoliative glaucoma; PG: pigmentary glaucoma; NA: not available; NR: not reported.

Figures and Tables -
Table 1. Eligibility criteria of included studies
Table 2. Postoperative complications reported by included studies

Comparison 1: iStent in combination with phacoemulsification vs phacoemulsification alone

Fea 2010

Adverse events

"No postoperative stent‐related adverse events were observed in these eyes [N = 24] through 48 months. IOP was well controlled in both groups throughout the entire follow‐up period; no secondary surgical intervention was required to control IOP."

Fernandez‐Barrientos 2010

2 iStents in combination with phacoemulsification at 1 year

Phacoemulsification alone at 1 year

Stent malposition

Authors noted that "six of the 34 (18%) implanted stents appeared to be malpositioned"

NA

Need for selective trabeculoplasty

0

1/16

NCT00721968

iStent in combination with phacoemulsification at 1 year

Phacoemulsification alone at 1 year

Posterior capsule opacification

4/27

1/17

IOP increase ≥ 10 mmHg vs baseline IOP at any visit

3/27

9/17

Conjunctivitis

3/27

2/17

Corneal abrasion

2/27

1/17

Iritis

2/27

0

Punctate corneal staining

1/27

1/17

Superficial punctate keratitis

1/27

1/17

Blurry vision

1/27

1/17

BCVA loss ≥ 1 line after 3 months postoperative

0

2/17

Eye pain

0

2/17

Retinal detachment

0

1/17

Samuelson 2011

iStent in combination with phacoemulsification at 2 years

Phacoemulsification alone at 2 years

Anticipated early postoperative event (as defined by investigators)

20/116

22/117

Posterior capsule opacification

7/116

12/117

Elevated IOP

5/116

8/117

Stent obstruction

5/116

NA

Blurry vision or visual disturbance

4/116

8/117

Stent malposition

3/116

NA

Iritis

1/116

6/117

Conjunctival irritation due to hypotensive medication

1/116

3/117

Disk hemorrhage

1/116

3/117

Comparison 2: iStent (or iStent inject) vs medical therapy

Fea 2014

iStent inject at 1 year (94 eyes of 94 participants)

Medical therapy at 1 year (98 eyes of 98 participants)

IOP decompensation

1/94

0

Soreness/discomfort

1/94

0

Eye burning

0

1/98

Medical allergy

0

1/98

Secondary glaucoma surgery

1/94

NA

Vold 2016

"Safety was favorable in both groups [Two iStents, N = 54; Medical therapy, N = 47; at 36 months). Two complications were reported during stent insertion in the surgery group, both of which were attributed to subject movement during surgery: one of these subjects had hyphema which resolved by day 1 and one subject had a small iridodialysis which resulted in no postoperative ocular sequelae...In the remaining non‐operated subjects, three‐year BCVA was 20/40 or better in 6 eyes (2 in stent group and 4 in med group), 20/100 in 1 eye (stent group), and 20/200 in 6 eyes (3 per group). No other post‐treatment adverse events were reported in either group."

Additional comparison: 1 iStent vs 2 iStents vs 3 iStents

Katz 2015

"No complications occurred intraoperatively or perioperatively, including no hypotony, choroidal effusion, hyphema, nor iridodialysis [One iStent, N=38; two iStents, N= 41; three iStents, N=40]. During 42 months of postoperative follow‐up, no device‐related or sight‐threatening adverse events occurred; furthermore, no eyes required additional glaucoma surgery. In this cohort of almost entirely phakic subjects (117 of 119) with mean baseline age between 62 and 69 years, the most common (and expected) adverse event over 3.5 years of follow‐up was progression of preexisting cataract. By Month 42 postoperatively, a total of eight one‐stent eyes, five two‐stent eyes, and seven three‐stent eyes had BCVA loss 1 line due to cataract progression. Of these cases, five one‐stent eyes, two two‐stent eyes, and three three‐stent eyes underwent cataract surgery by Month 42, and their IOP and medication data thereafter were excluded from efficacy analyses; two additional eyes (three‐stent group) had cataract surgery shortly after the Month 42 visit."

BCVA: best‐corrected visual acuity; IOP: intraocular pressure; N: number; NA: not available.

Figures and Tables -
Table 2. Postoperative complications reported by included studies
Table 3. Summary of financial support of included studies

Study

Pharmaceutical industry involvement

Other financial support

Comparison 1: iStent in combination with phacoemulsification vs phacoemulsification alone

Fea 2010

Glaukos Corporation provided funding/support

(including study devices)

Ricerca Finalizaata della Regione Pimonte 2007

Fernandez‐Barrientos 2010

Glaukos Corporation provided funding/support

NCT00721968

Glaukos Corporation provided funding/support

Samuelson 2011

Glaukos Corporation provided funding/support

(Investigators were consultants to Glaukos for the conduct of this study)

Comparison 2: iStents vs medical therapy

Fea 2014

Glaukos Corporation provided funding/support

(including study devices, editorial assistance, payment of article processing charges, financial support, and non‐study financial support)

Vold 2016

Glaukos Corporation provided funding/support

(including non‐financial, financial, and non‐study financial support to some/all authors)

Additional comparison: iStent vs 2 iStents vs 3 iStents

Katz 2015

Glaukos Corporation provided funding/support

(including study devices and non‐financial, financial, and non‐study financial support to some/all authors)

Figures and Tables -
Table 3. Summary of financial support of included studies
Comparison 1. iStent in combination with phacoemulsification versus phacoemulsification alone

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Proportion of participants who were drop‐free Show forest plot

2

Risk Ratio (M‐H, Fixed, 95% CI)

Subtotals only

1.1 At 6 to ≤ 18 months

2

239

Risk Ratio (M‐H, Fixed, 95% CI)

1.38 [1.18, 1.63]

2 Mean change in number of intraocular pressure (IOP)‐lowering drops taken per day from baseline Show forest plot

3

Mean Difference (IV, Fixed, 95% CI)

Subtotals only

2.1 At ≤ 6 months

1

33

Mean Difference (IV, Fixed, 95% CI)

‐0.4 [‐0.82, 0.02]

2.2 At 6 to ≤ 18 months

3

315

Mean Difference (IV, Fixed, 95% CI)

‐0.42 [‐0.60, ‐0.23]

3 Mean change in IOP Show forest plot

3

Mean Difference (IV, Random, 95% CI)

Totals not selected

3.1 At ≤ 6 months

1

Mean Difference (IV, Random, 95% CI)

0.0 [0.0, 0.0]

3.2 At 6 to ≤ 18 months (unmedicated IOP)

3

Mean Difference (IV, Random, 95% CI)

0.0 [0.0, 0.0]

Figures and Tables -
Comparison 1. iStent in combination with phacoemulsification versus phacoemulsification alone
Comparison 2. iStent (or iStent inject) versus medical therapy

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Proportion of participants who were drop‐free Show forest plot

2

Risk Ratio (M‐H, Random, 95% CI)

Subtotals only

1.1 At 6 to ≤18 months

2

286

Risk Ratio (M‐H, Random, 95% CI)

125.43 [17.80, 883.89]

1.2 At 18 to ≤ 36 months

1

101

Risk Ratio (M‐H, Random, 95% CI)

84.65 [5.36, 1336.23]

2 Mean change in intraocular pressure Show forest plot

1

Mean Difference (IV, Random, 95% CI)

Subtotals only

2.1 At ≤ 6 months

1

184

Mean Difference (IV, Random, 95% CI)

0.10 [‐0.72, 0.92]

2.2 At 6 to ≤ 18 months

1

184

Mean Difference (IV, Random, 95% CI)

‐0.60 [‐1.28, 0.08]

Figures and Tables -
Comparison 2. iStent (or iStent inject) versus medical therapy
Comparison 3. One iStent versus two iStents

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Proportion of participants who were drop‐free Show forest plot

1

Risk Ratio (M‐H, Fixed, 95% CI)

Totals not selected

1.1 At ≤ 6 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.2 At 6 to ≤ 18 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.3 At 18 to ≤ 36 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.4 At > 36 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

2 Mean change in intraoperative pressure Show forest plot

1

Mean Difference (IV, Random, 95% CI)

Subtotals only

2.1 At 6 to ≤ 18 months

1

69

Mean Difference (IV, Random, 95% CI)

0.0 [0.0, 0.0]

Figures and Tables -
Comparison 3. One iStent versus two iStents
Comparison 4. One iStent versus three iStents

Outcome or subgroup title

No. of studies

No. of participants

Statistical method

Effect size

1 Proportion of participants who were drop‐free Show forest plot

1

Risk Ratio (M‐H, Fixed, 95% CI)

Totals not selected

1.1 At ≤ 6 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.2 At 6 to ≤ 18 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.3 At 18 to ≤ 36 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

1.4 At > 36 months

1

Risk Ratio (M‐H, Fixed, 95% CI)

0.0 [0.0, 0.0]

2 Mean change in intraocular pressure Show forest plot

1

Mean Difference (IV, Random, 95% CI)

Subtotals only

2.1 At 6 to ≤ 18 months

1

67

Mean Difference (IV, Random, 95% CI)

0.0 [0.0, 0.0]

Figures and Tables -
Comparison 4. One iStent versus three iStents