ModifiedUnitedHealthcarePolicy CS050ID.B

Glaucoma Surgical Treatments (for Idaho Only)

Medical policy governing coverage and medical necessity of surgical and laser treatments for glaucoma in the state of Idaho, including Idaho Medicaid Plus plans, and applicable coding guidance.

Policy Summary

PayerUnitedHealthcare

PolicyGlaucoma Surgical Treatments (for Idaho Only)

Policy CodePolicy CS050ID.B

Change TypeMaterial revisionsadded indications and coding updates

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionObtain plan prior authorization where required and document indication, baseline IOP, medication history, device model, and whether procedure is combined with cataract surgery.

SourceLink

POLICY UPDATE CHANGES

Added goniotomy, trabeculotomy, ab‑interno canaloplasty, and combined canaloplasty/trabeculotomy (e.g., OMNI, Streamline) as proven and medically necessary when performed with cataract surgery for adults with mild–moderate open‑angle glaucoma on ocular hypotensive medication.

Added laser procedures (laser trabeculoplasty, laser iridotomy/iridectomy, laser iridoplasty, and laser ciliary body destruction) to the list of proven and medically necessary indications.

Removed prior statement listing goniotomy or trabeculotomy for pediatric glaucoma (age ≤18 years).

Replaced wording that limited glaucoma drainage devices to 'some' devices with an inclusive statement listing glaucoma drainage devices (e.g., XEN, EX‑PRESS, Molteno, Baerveldt, Ahmed, Krupin‑Denver) for refractory glaucoma when medical or surgical treatments have failed or are inappropriate.

Added CPT codes 0621T, 0622T, 0730T, 65855, 66710, 66711, 66761, and 66762 to Applicable Codes.

state-specificApplies to

8new CPT codes

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

new indications added

20-60%IOP reduction (iStent range)

369 vs 187HORIZON trial arms

Coverage Criteria for Glaucoma Procedures

Covered procedures

The following surgical and laser glaucoma procedures are considered proven and medically necessary when used for the indicated populations and contexts:

Procedures proven and medically necessary: Goniotomy, trabeculotomy, canaloplasty (ab interno), or combined canaloplasty (ab interno) and trabeculotomy (e.g., OMNI Surgical System, Streamline Surgical System) when used in combination with cataract surgery for treating mild to moderate open-angle glaucoma (OAG) and cataract in individuals currently being treated with ocular hypotensive medication; iStent, iStent inject, or Hydrus Microstent when used in combination with cataract surgery for treating mild to moderate OAG and cataract in individuals currently being treated with ocular hypotensive medication; Drainage devices (e.g., XEN System, EX-PRESS, Molteno implant, Baerveldt tube shunt, Ahmed glaucoma valve implant, Krupin-Denver valve implant) for treating refractory glaucoma when medical or surgical treatments have failed or are inappropriate; Laser trabeculoplasty (e.g., Argon, Selective); Laser iridotomy/iridectomy (e.g., Nd:YAG); Laser iridoplasty; Laser ciliary body destruction.

Each listed procedure is asserted as proven and medically necessary in the contexts specified.

MIGS indications and expectations

MIGS-specific coverage considerations:

MIGS candidate criteria: MIGS are typically indicated for candidates with mild to moderate glaucoma, often performed in conjunction with phacoemulsification; they are generally not suitable for advanced disease requiring very low target IOPs.MIGS should offer at least 20% IOP reduction or a reduction of at least one glaucoma medication

Examples include trabecular bypass stents (iStent, iStent inject, Hydrus), goniotomy/excisional approaches (KDB, Trabectome, GATT), ab-interno canaloplasty (ABiC, VISCO360, Streamline/OMNI), suprachoroidal or subconjunctival shunts (e.g., XEN), and ciliary body ablation procedures.

Evidence summary — no explicit coverage criteria in excerpt

Evidence summary nodes: This section summarizes comparative effectiveness and safety evidence for multiple glaucoma devices (iStent/iStent inject, Hydrus, EX-PRESS, Ahmed/Baerveldt/Molteno tube shunts, XEN). Reported outcomes include IOP reduction, medication burden, adverse events, and follow-up durations (often 12–24 months, up to 5 years for select studies).

No explicit coverage determination or stepwise criteria provided in this excerpt.

Evidence summaries and considerations

Evidence summaries and comparative outcomes for interventions

Ahmed vs Baerveldt outcomes: A multicenter RCT (Budenz et al. 2011; n=276) found both AGV and BGI lowered IOP at 1 year; mean IOP was 15.4 mmHg (AGV) vs 13.2 mmHg (BGI). Early postoperative complications and serious complications were more frequent with BGI (58% and 34%) than AGV (43% and 20%). Cumulative 1-year failure rates were 16.4% (AGV) vs 14% (BGI).

Supports consideration of safety trade-offs when selecting tube shunt type.

XEN Gel Stent evidence: Systematic reviews and multiple observational studies report XEN lowers IOP (approximately 25–35% with mean IOP often ~13–16 mmHg) and reduces medication use, but most evidence is retrospective with high risk of bias and variable needling and reintervention rates; comparisons with trabeculectomy suggest trabeculectomy may be somewhat more effective.

Frequent postoperative interventions and limited randomized data noted.

SLT (Selective Laser Trabeculoplasty): The LIGHT RCT demonstrated SLT provided superior long-term disease control versus drops at 6 years, with 69.8% of SLT patients at or below target IOP without further intervention, and less progression in the SLT arm.

General evidence sufficiency statement

Evidence summary and applicability

Evidence sufficiency: Many available studies are single-arm case series or retrospective cohorts with small samples, short follow-up, and potential manufacturer sponsorship bias; therefore comparative effectiveness and long-term safety for several procedures remain uncertain.

See cited systematic reviews, HTA and interim RCTs for specifics.

Coverage-relevant evidence considerations

Evidence summary and considerations that would underpin coverage determinations

Evidence quality and outcomes: RCTs, comparative studies, and numerous nonrandomized reports describe modest IOP reductions and decreased medication use with ab-interno approaches (KDB, GATT, Trabectome, combined OMNI procedures), often when combined with phacoemulsification; however many studies are limited by design, size, and follow-up duration.

Supports cautious coverage and need for higher-quality long-term data.

Reported benefits: Some RCTs and comparative studies report higher proportions achieving ≥20% IOP reduction or medication reductions (e.g., KDB-Phaco vs iStent-Phaco composite outcomes through 12 months), and OMNI/combined canaloplasty series report substantial medication-free proportions at 6–12 months.

Magnitude of benefit varies by baseline IOP and surgical intent.

Reported harms/limitations: Short-term adverse events commonly include hyphema and transient IOP spikes; limitations across the literature include retrospective designs, small samples, short follow-up, and possible conflicts of interest.

Short-term safety generally favorable compared to trabeculectomy, but long-term comparative safety is uncertain.

Coverage stance by device/evidence level

Coverage considerations based on device/procedure type and evidence:

MIGS with established evidence and FDA approval for use with cataract surgery: Devices/procedures with FDA approval for use in combination with phacoemulsification (e.g., iStent, iStent Inject, Hydrus) and supported by randomized trials showing modest IOP and medication reductions may be considered when performed with cataract surgery and when clinically appropriate.

AAO guidance notes modest IOP reduction and favorable short-term safety; some devices are approved only when combined with phaco.

Aqueous shunts and trabeculectomy alternatives: Aqueous shunts with extraocular reservoirs (valved and nonvalved) have level I evidence supporting use in adult OAG, particularly in eyes with prior incisional surgery; nonvalved devices generally achieve lower long-term IOPs but may have different complication profiles.

AAO Technology Assessment provides evidence for these statements.

Procedures with insufficient or limited evidence: Excimer laser trabeculostomy (ELT), femtosecond laser trabeculotomy (FLT), OCT-guided laser trabeculotomy, and similar investigational laser approaches lack sufficient high-quality evidence and are not FDA-approved for glaucoma in the US; routine coverage may be restricted absent compelling evidence or trial context.

MIGS and ab interno canaloplasty combined with cataract surgery

Revised list of proven and medically necessary indications (summary of additions):

Combined canaloplasty/trabeculotomy with cataract: Goniotomy, trabeculotomy, canaloplasty (ab interno), or combined canaloplasty (ab interno) and trabeculotomy (e.g., OMNI Surgical System, Streamline Surgical System) are medically necessary for adults (age ≥19 years) when used in combination with cataract surgery to treat mild to moderate open-angle glaucoma in adults currently being treated with ocular hypotensive medication.

Added as proven and medically necessary per policy revision.

Laser procedures

Laser procedures added as proven and medically necessary:

Proven laser procedures: Laser trabeculoplasty (e.g., Argon, Selective), laser iridotomy/iridectomy (e.g., Nd:YAG), laser iridoplasty, and laser ciliary body destruction are listed as proven and medically necessary indications.

Policy explicitly adds these laser procedures to the proven list.

Glaucoma drainage devices (refractory cases)

Glaucoma drainage devices for refractory glaucoma:

Drainage devices for refractory glaucoma: Glaucoma drainage devices (e.g., XEN System, EX-PRESS, Molteno implant, Baerveldt tube shunt, Ahmed glaucoma valve implant, Krupin-Denver valve implant) are medically necessary for treating refractory glaucoma when medical or prior surgical treatments have failed or are inappropriate.

Wording was broadened in the policy revision to list these devices inclusively for refractory cases.

The policy states that "All other FDA approved types of laser procedures are unproven and not medically necessary for treating any type of glaucoma due to insufficient evidence of efficacy and/or safety." This explicit exclusion applies to FDA‑approved laser procedures that are not listed among the policy's proven and medically necessary laser interventions (for example, when not identified as laser trabeculoplasty, laser iridotomy/iridectomy, laser iridoplasty, or laser ciliary body destruction).

Many clinical trials and systematic reviews summarized in the policy limited enrollment or excluded certain glaucoma subtypes such as secondary open‑angle glaucomas and eyes with prior ocular surgery or other comorbidities. These inclusion restrictions reduce generalizability of trial results to broader clinical populations and should be considered when extrapolating outcomes to patients outside the studied cohorts.

Comparative evidence for cyclodestructive procedures is inconclusive. A Cochrane review found limited and inconsistent trial data, with common serious adverse events including hypotony and phthisis bulbi, and concluded that larger, well‑designed randomized trials are needed before firm comparative conclusions can be drawn.

Several procedures are supported primarily by short‑term, single‑center case series without randomized comparative data or long‑term follow‑up. Such evidence suffices for preliminary safety and feasibility signals but is insufficient to establish durable comparative effectiveness or long‑term safety.

Evidence for standalone Kahook Dual Blade (KDB) trabeculectomy is limited. Published assessments and comparative studies are retrospective or small, with short follow‑up and potential conflicts of interest, leaving large gaps in high‑quality comparative evidence for standalone KDB beyond short‑term outcomes.

Laser procedures that are not FDA‑approved for glaucoma in the U.S. (for example, excimer laser trabeculostomy, femtosecond laser trabeculotomy, and OCT‑guided laser trabeculotomy) have insufficient peer‑reviewed evidence to support routine use. Existing studies are few, small, and often nonrandomized, and do not provide adequate data on long‑term safety and effectiveness.

The policy clarifies that any FDA‑approved laser procedure not specifically listed among the policy's proven and medically necessary laser interventions is considered unproven and not medically necessary for treating glaucoma, unless supportive high‑quality evidence is provided.

Revision history notes removal of prior language regarding goniotomy or trabeculotomy for pediatric glaucoma and other related exclusions; specifically, the policy removed the previous statement that goniotomy or trabeculotomy for pediatric glaucoma (age ≤18 years) was unproven and not medically necessary.

The document reiterates that laser procedures explicitly named as proven and medically necessary include laser trabeculoplasty (Argon, Selective), laser iridotomy/iridectomy (Nd:YAG), laser iridoplasty, and laser ciliary body destruction; other FDA‑approved laser procedures not on that list are noted as unproven.

Within the excerpted sections there are no additional explicit statements labeling specific device uses as ‘not medically necessary’; however, the policy repeatedly highlights evidence limitations that may inform determinations of noncoverage or investigational status for procedures lacking adequate comparative or long‑term data.

The XEN Gel Stent has observational and systematic review data showing clinically meaningful IOP lowering and medication reduction, but most studies are retrospective with variable quality and heterogeneity. Systematic assessments characterize the XEN as having potential benefit but overall low‑quality evidence, leaving comparative advantage over trabeculectomy or other shunts unproven.

Ab‑interno canaloplasty (including devices such as Streamline and procedures like OMNI/ABiC) currently lacks sufficient high‑quality randomized data and long‑term follow‑up to establish comparative effectiveness. Existing reports are largely single‑center case series or interim study reports with short follow‑up and risk of bias; larger multicenter RCTs are needed to define long‑term outcomes.

Although the policy does not list additional explicit 'not medically necessary' conditions beyond the stated exclusions for unspecified FDA‑approved lasers, it emphasizes that insufficient or low‑quality evidence for a device or procedure may lead to categorization as unproven or not medically necessary for routine coverage.

Standalone use of devices or procedures that lack FDA indication for standalone glaucoma surgery (for example certain microinvasive devices approved only with cataract surgery or investigational laser trabeculotomy techniques) is not supported by adequate evidence in the literature and may therefore be considered investigational or not medically necessary unless compelling documentation or trial context is provided.

The policy states that procedures and indications not listed among the policy's proven and medically necessary treatments — including unspecified FDA‑approved laser procedures not explicitly named — are considered unproven and not medically necessary due to insufficient evidence of efficacy.

Applicable Codes and Identifiers

Applicable CPT Codes (selected)CPT

0253T	Insertion of anterior segment aqueous drainage device, without extraocular reservoir, internal approach, into the suprachoroidal space.
0449T	Insertion of aqueous drainage device, without extraocular reservoir, internal approach, into the subconjunctival space; initial device.
0450T	Insertion of aqueous drainage device, without extraocular reservoir, internal approach, into the subconjunctival space; each additional device (List separately in addition to code for primary procedure).
0474T	Insertion of anterior segment aqueous drainage device, with creation of intraocular reservoir, internal approach, into the supraciliary space.
0621T	Trabeculostomy ab interno by laser.
0622T	Trabeculostomy ab interno by laser; with use of ophthalmic endoscope.
0671T	Insertion of anterior segment aqueous drainage device into the trabecular meshwork, without external reservoir, and without concomitant cataract removal, one or more.
0730T	Trabeculotomy by laser, including optical coherence tomography (OCT) guidance.
65820	Goniotomy.
65855	Trabeculoplasty by laser surgery.

1–10 of 17

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Applicable CPT Codes (cataract-combined)CPT

66761	Iridotomy/iridectomy by laser surgery (e.g., for glaucoma) (per session).
66762	Iridoplasty by photocoagulation (1 or more sessions) (e.g., for improvement of vision, for widening of anterior chamber angle).
66989	Extracapsular cataract removal with insertion of intraocular lens prosthesis (complex) with insertion of intraocular anterior segment aqueous drainage device, without extraocular reservoir, internal approach, one or more.
66991	Extracapsular cataract removal with insertion of intraocular lens prosthesis; with insertion of intraocular anterior segment aqueous drainage device, without extraocular reservoir, internal approach, one or more.

HCPCS CodesHCPCS

L8612

Aqueous shunt

FDA product codes / PMA / 510(k) identifiers mentionedmixed

K062259	iTRACK Canaloplasty Ophthalmic Microcannula (predicate / 510(k))
K211680	Streamline Surgical System (Streamline Viscoelastic Injector)
K030350	ExPRESS Mini Glaucoma Shunt (501(k))
K172559	OMNI Surgical System (product code references MRH/HMZ) (device PMN info)
P170043	iStent Inject PMA (approval P170043)
GTS100R/L	iStent Trabecular Micro-Bypass Stent System model identifiers
P170034	Hydrus Microstent PMA (P170034)
K161457	XEN Glaucoma Treatment System
K230722	Eagle laser device for SLT
K140336	OPTIMIS FUSION Ophthalmic Laser Systems family

Added Applicable CPT CodesCPT

0621T
0622T
0730T
65855
66710
66711
66761
66762

MIGS effectiveness threshold

Effectiveness thresholdMIGS should provide at least a 20% reduction in intraocular pressure (IOP) or a reduction of at least one glaucoma medication.

Typical candidate severityIntended for patients with mild to moderate glaucoma; not generally suitable for advanced disease requiring very low IOP targets.

Common procedural contextOften performed via an ab interno approach and commonly combined with phacoemulsification (cataract) surgery.

Comparative expectationGenerally yields more modest IOP lowering than trabeculectomy or aqueous shunt surgery, with postoperative pressures typically in the mid-to-upper teens.

Provider Actions, Prior Authorization, and Documentation

Prior Authorization

Prior Authorization for Device‑Specific or Off‑Label Standalone Use

Prior authorization may be required for device‑specific or off‑label standalone use of MIGS devices (for example, iStent, iStent inject, Hydrus, XEN) when the device is not FDA‑approved as a standalone procedure or when use is outside the device's labeled indication. Requests should include clinical rationale demonstrating medical necessity and documentation of prior therapies.

Include device model and implant details
If device is FDA‑approved only with concurrent cataract surgery, document why standalone use is medically necessary

Prior Authorization

Prior Authorization for Added CPT‑Coded Procedures

Providers must follow plan prior authorization rules for newly added or other CPT‑coded procedures related to glaucoma devices and MIGS. When billing for additional CPT codes that have been introduced or added to the member's plan, obtain prior authorization where required and submit all supporting clinical documentation.

Verify payer CPT requirements and code list before scheduling

Background and Context

Background: Glaucoma is a group of progressive optic neuropathies associated with elevated intraocular pressure that can lead to optic nerve damage and visual field loss. Primary open‑angle glaucoma (POAG) is the adult‑onset form with open anterior chamber angles and is classified by severity based on optic nerve/RNFL findings and visual field testing.

Definitions and Device/Procedure Descriptions

POAG / primary open-angle glaucoma definition

DefinitionPrimary open-angle glaucoma (POAG) is a chronic, progressive optic neuropathy with optic nerve atrophy and visual field loss, adult onset, open anterior chamber angles, and absence of other explanations for glaucomatous optic nerve change.

Key diagnostic featuresEvidence of optic nerve damage (optic disc or RNFL structural abnormalities) and reliable, reproducible visual field abnormality.

Onset and anatomyTypically adult-onset with open anterior chamber angles.

Severity classificationSeverity is classified as mild, moderate, severe, or indeterminate based on optic nerve/RNFL findings and standard automated perimetry (SAP).

MIGS / Microinvasive glaucoma surgery definition

Definition

Policy Revision History

2026-05-01policy_revisionLatest

Revised list of proven and medically necessary indications: added goniotomy, trabeculotomy, ab‑interno canaloplasty, combined ab‑interno canaloplasty and trabeculotomy (e.g., OMNI, Streamline) for adults when combined with cataract surgery; added laser trabeculoplasty (Argon, SLT), laser iridotomy/iridectomy (Nd:YAG), laser iridoplasty, and laser ciliary body destruction; removed pediatric goniotomy/trabeculotomy exclusion and broadened wording for glaucoma drainage devices to include listed devices for refractory glaucoma.

Policy Summary

PayerUnitedHealthcare

PolicyGlaucoma Surgical Treatments (for Idaho Only)

Policy CodePolicy CS050ID.B

Change TypeMaterial revisionsadded indications and coding updates

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionObtain plan prior authorization where required and document indication, baseline IOP, medication history, device model, and whether procedure is combined with cataract surgery.

SourceLink

On This Page

Supports SLT as an initial or adjunctive therapy for POAG/OHT.

Laser iridotomy/iridoplasty: LPI increases angle width and has a favorable safety profile for angle-closure spectrum eyes; evidence for adjunctive iridoplasty (LPIp) is mixed with limited data on additional IOP lowering beyond LPI.

LPI recommended for angle-closure suspect or PAC stages per AAO assessment.

Cyclodestructive procedures: Systematic reviews indicate limited and inconclusive comparative evidence for cyclodestruction; reported adverse events include hypotony and phthisis bulbi, and these procedures are traditionally reserved for refractory glaucoma.

Selection should be individualized per clinician judgment.

Ab-interno canaloplasty (Streamline/OMNI): Interim RCT (VENICE) and observational studies show similar short-term IOP lowering and medication reductions compared with some stent procedures at 6 months, but follow-up is short and evidence quality is limited; larger RCTs with longer follow-up are needed.

Insufficient long-term evidence to fully establish comparative effectiveness.

Systematic reviews and HTA note limited/uncertain evidence for these laser techniques.

Procedures after failed filtration surgery: Ab-interno trabeculectomy or other ab-interno approaches may be used after failed trabeculectomy in select cases, but supporting data are from small, nonrandomized cohorts; coverage decisions should consider prior surgical history and expected benefit on a case-by-case basis.

Cohort evidence indicates possible benefit but limited generalizability.

Attach operative report, CPT codes, and indication with the prior authorization request

Documentation Required

Evidence Notes Higher Early and Serious Postoperative Complications

Evidence indicates higher early and serious postoperative complications with some devices (e.g., Baerveldt compared with Ahmed). When requesting coverage for aqueous shunts or drainage devices, include documentation of risk/benefit assessment and prior surgical history.

Document prior ocular surgeries and reason for selecting specific implant
Provide discussion of anticipated complication risks and monitoring plan

Denial Risk

Evidence‑Based Denial Risk for Low‑Quality or Limited Evidence

Limitations in the quality and duration of evidence (retrospective designs, short follow‑up, or high risk of bias) may result in requests for additional documentation or denial of coverage. Procedures supported only by low‑quality or single‑arm case series carry increased denial risk.

Submit randomized trial data or long‑term follow‑up when available
If only observational evidence exists, provide comprehensive clinical justification

Documentation Required

Postoperative Follow‑Up and Documentation

Vigilant postoperative follow‑up and documentation are expected for many MIGS and drainage device procedures. Postoperative course should be documented including needling, bleb management, secondary surgeries, complications, and changes in medications and IOP.

Document all postoperative interventions (e.g., needling, MMC use) and dates
Report pre‑ and postoperative IOPs and number of IOP‑lowering medications at each follow‑up visit

Documentation Required

Document Device and Concurrent Cataract Surgery

Always document device model and whether the procedure was performed concurrently with cataract surgery. This is required when device approvals are limited to combination use (e.g., iStent, iStent inject, Hydrus) and to substantiate medical necessity.

Specify device make/model and lot if available
Indicate concurrently performed cataract extraction (phacoemulsification) or standalone status

Step Therapy

Stepwise Consideration of Less Invasive Interventions

Consider a stepwise approach favoring less invasive interventions (e.g., SLT, medication optimization) before moving to MIGS or filtration procedures when clinically appropriate. Provide documentation of prior therapies and rationale for escalating to a surgical device given limited long‑term comparative data.

Document prior medication trials and response, laser treatments (e.g., SLT) and outcomes
Explain why less invasive options are inadequate or inappropriate for the specific patient

Microinvasive glaucoma surgery (MIGS) is a group of ab interno, minimally disruptive procedures that lower IOP via microstents, trabecular bypass, trabeculotomy, canaloplasty, or subconjunctival approaches and are often combined with cataract surgery.

Clinical roleMIGS carry lower complication risk than traditional filtering surgery but typically produce more modest IOP reduction and are intended for mild-to-moderate glaucoma.

Outcome expectationProcedures should provide ≥20% IOP reduction or reduce glaucoma medications by ≥1.

Regulatory noteSome MIGS are FDA-approved only when performed concurrently with phacoemulsification; surgeon judgment is recommended for patient selection.

iStent / iStent inject description

Device typeTrabecular micro-bypass stents implanted via an ab interno approach (examples: iStent, iStent inject).

Generational notesFirst- and second-generation iStent devices exist; outcomes vary by number of stents implanted (2 stents often yield greater IOP reduction than 1).

Common useTypically implanted in combination with phacoemulsification; combined phaco-iStent has shown greater IOP and medication reduction compared with phaco alone in randomized and meta-analytic data.

Safety/adverse eventsReported adverse events include IOP elevation, stent blockage/obstruction, stent malposition, and hyphema.

Hydrus Microstent description

Device typeA Schlemm's-canal–based microstent implanted via an ab interno approach (Hydrus Microstent).

Clinical evidenceRandomized trials (including HORIZON) show Hydrus + cataract surgery improves medication-free rates and produces greater IOP and medication reduction versus cataract surgery alone, with follow-up data up to 5 years.

Safety profileOverall favorable safety; focal peripheral anterior synechiae reported more frequently with Hydrus.

Comparative strengthNetwork meta-analyses suggest Hydrus may have slight advantage over 1- or 2-iStent combined with phaco for IOP lowering, though evidence limitations exist.

EX-PRESS device description

Device typeA glaucoma filtration device implanted under a scleral flap (EX-PRESS glaucoma filtration device).

EfficacyRandomized trials and meta-analyses found EX-PRESS provided better IOP control and higher complete success rates at 1 year compared with trabeculectomy and sustained advantages up to 3–5 years in some studies.

SafetyEX-PRESS was associated with fewer increases in IOP, less hyphema, and fewer postoperative interventions compared with trabeculectomy in pooled RCT evidence.

Tube shunts (Ahmed, Baerveldt, Molteno) description

Device classAqueous shunt implants (tube shunts) including Ahmed, Baerveldt, and Molteno devices that divert aqueous to an external reservoir/plate.

Comparative outcomesSystematic reviews and RCTs show mixed IOP outcomes versus trabeculectomy; Baerveldt may achieve lower long-term IOPs but with higher early and serious complication rates compared with Ahmed.

Clinical roleUsed across various glaucoma types and commonly indicated for refractory glaucoma or eyes with prior incisional surgery.

XEN Gel Stent description

Device typeA subconjunctival gelatin stent (XEN Gel Stent) that drains aqueous into the subconjunctival space.

Evidence summaryObservational studies and systematic reviews report IOP reductions typically to mean ~13–16 mmHg and percent IOP reductions around 25–56% at 12 months; evidence is largely retrospective with variable long-term data up to 5 years.

Postoperative considerationsHigh variability in postoperative interventions including needling (reported rates up to ~32–62% in some series), requiring vigilant follow-up.

Comparative positionComparisons with trabeculectomy suggest trabeculectomy may be somewhat more effective in IOP lowering in some analyses.

Refractory glaucoma definition

DefinitionRefractory glaucoma is glaucoma not controlled by prior filtering or cilioablative procedures and/or uncontrolled IOP on maximally tolerated medical therapy.

Indicated interventionsGlaucoma drainage devices (e.g., XEN, EX-PRESS, Molteno, Baerveldt, Ahmed, Krupin-Denver) are appropriate options when medical or prior surgical treatments have failed or are inappropriate.

Clinical contextTreatment decisions should consider prior surgeries, IOP goals, and risk of complications; comparative evidence across devices shows differing efficacy and safety profiles.

Needling definition

DefinitionNeedling is a postoperative subconjunctival procedure performed to restore flow through a bleb or subconjunctival stent (e.g., commonly required after XEN implantation).

IndicationPerformed for bleb revision or to address fibrosis/scar limiting filtration after subconjunctival drainage device implantation.

Frequency noteNeedling rates are variable and can be substantial in some XEN series; vigilant postoperative follow-up is required.

ABiC / ab-interno canaloplasty description

ProcedureAb-interno canaloplasty (ABiC) is a viscodilation procedure of Schlemm's canal performed from an internal approach using microcatheterization and viscodilation to restore physiologic outflow.

Examples/devicesExamples include VISCO360 and devices used for microcatheterization; related devices such as iTRACK are FDA-cleared microcannulae for canal procedures.

Typical usePerformed alone or combined with cataract surgery to reduce IOP and medication burden in mild-to-moderate OAG; evidence includes case series with short-term follow-up.

Combined canaloplasty and trabeculotomy (OMNI) description

Procedure descriptionCombined canaloplasty and trabeculotomy (e.g., OMNI Surgical System) integrates 360° canal viscodilation (canaloplasty) with trabeculotomy (up to 180–360°) using a single device to improve aqueous outflow.

Clinical useOften performed concomitantly with phacoemulsification in patients with mild to moderate OAG to lower IOP and reduce medication burden.

EvidenceCase series and multicenter reports show substantial proportions achieving ≥20% IOP reduction and medication reductions through 6–12 months; RCT evidence is limited and generally low quality to moderate quality.

KDB goniotomy description

Device/procedureKahook Dual Blade (KDB) goniotomy is an excisional goniotomy that removes a strip of trabecular meshwork tissue via an internal approach.

Clinical contextOften combined with phacoemulsification (phaco-KDB) to lower IOP and reduce medication burden in mild-to-moderate OAG.

EvidenceRCTs and comparative studies report KDB-Phaco may achieve similar or greater rates of the composite outcome (≥20% IOP reduction or ≥1 medication reduction) compared with phaco-iStent through 12 months; evidence varies and longer-term data are limited.

MIGS general definition

Concise definitionMIGS are minimally invasive glaucoma surgeries that lower IOP by targeting aqueous outflow pathways (trabecular meshwork/Schlemm's canal or subconjunctival routes) using microstents, trabeculotomy, goniotomy, or canaloplasty with smaller incisions and generally more favorable short-term safety than traditional filtration surgery.

Typical indicationPrimarily indicated for mild-to-moderate OAG and often performed with cataract surgery; not generally suitable for advanced glaucoma needing very low IOP targets.

Expected outcomesModest IOP reductions with postoperative pressures commonly in the mid-to-upper teens and potential reduction in glaucoma medication burden.

Kahook Dual Blade (KDB) device description

DeviceKahook Dual Blade (KDB) is an excisional goniotomy device designed to remove a strip of trabecular meshwork to increase aqueous outflow.

UsageUsed standalone or combined with cataract surgery; commonly studied in phaco-KDB comparisons to trabecular bypass stents.

Evidence summaryRCTs show KDB-Phaco can achieve clinically meaningful IOP and medication reductions; comparative results versus stents vary and long-term data are limited.

MIGS group summary (alternate)

Group summaryMIGS encompasses multiple ab interno procedures (trabecular bypass stents, excisional goniotomy, trabeculotomy, ab-interno canaloplasty) and subconjunctival and suprachoroidal approaches that aim for modest IOP reduction with improved short-term safety compared to filtration surgery.

Clinical considerationsMany MIGS devices have strongest evidence when performed with cataract surgery; some devices are FDA-approved only in combination with phacoemulsification.

Evidence limitationsMost studies are short-term, single-center, or retrospective; randomized head-to-head and long-term outcome data remain limited for many devices.

ELT / FLT / OCT-guided laser trabeculotomy definitions

DefinitionsELT (excimer laser trabeculostomy), FLT (femtosecond laser trabeculotomy), and OCT-guided laser trabeculotomy are laser-based trabecular meshwork procedures under investigation for glaucoma treatment.

Regulatory statusThese laser techniques are not currently FDA-approved for glaucoma treatment in the U.S.; available evidence is limited and of low quality.

Evidence considerationsSmall single-arm studies and limited RCTs report promising IOP reductions in some series, but larger multi-center RCTs and longer follow-up are needed to establish safety and effectiveness.

ab interno canaloplasty / combined canaloplasty and trabeculotomy definitions (new additions)

Ab interno canaloplastyA viscodilation technique performed from an internal approach (examples: VISCO360, iTRACK microcannula) intended to restore Schlemm's canal physiology and reduce IOP; evidence consists mainly of case series and short-term reports.

Combined canaloplasty + trabeculotomyCombined procedures (e.g., OMNI Surgical System, Streamline) perform 360° canal viscodilation plus trabeculotomy in one device to increase outflow; studied mostly in conjunction with phacoemulsification with favorable short-term outcomes.

Evidence statusECRI and other reviews consider available evidence low to very-low quality, recommending further RCTs with longer follow-up to confirm comparative effectiveness.

MIGS — concise definition (new additions)

Concise MIGS definitionMIGS are minimally invasive procedures that lower IOP by enhancing physiologic outflow (trabecular bypass, trabeculotomy, canaloplasty) or by routing flow to the subconjunctival/suprachoroidal space, typically via ab interno approaches and often combined with cataract surgery.

Clinical expectationProvide modest IOP lowering (often mid-to-upper teens postoperatively) and reduction in medication burden, with favorable short-term safety compared to trabeculectomy/shunts.

Policy update noteRecent policy revisions explicitly added several ab-interno canaloplasty and trabeculotomy procedures (e.g., OMNI, Streamline) as proven and medically necessary when combined with cataract surgery for mild-to-moderate OAG.