CurrentPremera BluecrossPolicy MP-124

Glaucoma, Invasive Procedures (Invasive glaucoma procedures: stents, drainage/filtration devices, canaloplasty)

Defines medical necessity criteria for invasive procedures used to lower intraocular pressure in glaucoma patients and the diagnostic codes under which these procedures may be covered; intended for providers and Premera coverage staff.

Policy Summary

PayerPremera Bluecross

PolicyGlaucoma, Invasive Procedures (Invasive glaucoma procedures: stents, drainage/filtration devices, canaloplasty)

Policy CodePolicy MP-124

Change TypeCriteria revised (operational)

Effective DateJul 1, 2025

Next Review DateJul 1, 2025

Key ActionObtain prior authorization and submit clinical documentation demonstrating prior medical/laser therapy and IOP response (≥25% reduction not achieved) when requesting listed procedures.

SourceLink

POLICY UPDATE CHANGES

Policy criteria updated for Aqueous drainage/filtration devices, Implantable Stents, and Canaloplasty; Background section was removed; references updated.

MP-124Policy ref

Jul 1, 2025Effective

Jun 9, 2025Last revised

66174,66175,66183Key procedure codes

H40.*Diagnosis codes

Policy Summary

PayerPremera Bluecross

PolicyGlaucoma, Invasive Procedures (Invasive glaucoma procedures: stents, drainage/filtration devices, canaloplasty)

Policy CodePolicy MP-124

Change TypeCriteria revised (operational)

Effective DateJul 1, 2025

Next Review DateJul 1, 2025

Key ActionObtain prior authorization and submit clinical documentation demonstrating prior medical/laser therapy and IOP response (≥25% reduction not achieved) when requesting listed procedures.

SourceLink

On This Page

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.

Coverage Criteria for Invasive Glaucoma Procedures

Medical necessity criteria by procedure type

Use of invasive procedures to treat glaucoma may be considered medically necessary when ALL of the following general conditions apply:

General requirement: Failure to respond to medical therapy defined as inability to reduce intraocular pressure (IOP) by >=25% from the IOP measured at diagnosis (target pressure)IOP reduction <25%

From policy definition of failure to respond

Aqueous drainage/filtration devices - Indications: Moderate to severe open-angle glaucoma when medications and laser therapy are insufficient to control disease; trabeculectomy has failed or is deemed unlikely to succeed; presence of conjunctival scarring; poorly controlled IOP with a moderate cataract (performed in advance of cataract surgery); complex glaucoma (including neovascular glaucoma, uveitic glaucoma, or significant peripheral anterior synechiae)

Devices considered for these specific clinical situations

Implantable stents (mild to moderate OAG): Used in conjunction with concurrent phacoemulsification cataract surgery for targeted IOP reduction from specific areas of outflow resistance in individuals with no significant angle abnormalities

Stents are specified for use with cataract surgery

Canaloplasty indications: For mild to moderate POAG, pigmentary glaucoma, exfoliation glaucoma, or POAG mixed with another mechanism when moderate IOP reduction is needed to preserve visual field; when trabeculectomy has failed or is deemed unlikely to succeed; to avoid conjunctival disruption/bleb-creation; after failed laser trabeculoplasty without scarring; after multiple medications/procedures have failed to produce IOP reduction to target range; for individuals with healthy angle structures or high risk of significant continued vision loss

Canaloplasty indicated in specified surgical and anatomic contexts

This policy distinguishes among invasive glaucoma procedures by the anatomic and clinical context in which they are appropriate. Implantable stents are specified for use in conjunction with concurrent phacoemulsification cataract surgery to target outflow resistance in patients with mild to moderate open‑angle glaucoma who have no significant angle abnormalities. By contrast, canaloplasty is intended for patients with mild to moderate primary open‑angle glaucoma (including pigmentary or exfoliation forms or mixed‑mechanism disease) who have healthy angle structures and require a moderate reduction in intraocular pressure (IOP) to preserve the visual field. Aqueous drainage/filtration devices are reserved for more advanced or complex presentations (for example, moderate to severe open‑angle glaucoma when medications and laser therapy are insufficient, failed or unlikely‑to‑succeed trabeculectomy, presence of conjunctival scarring, poorly controlled IOP with a moderate cataract planned, or complex glaucomas such as neovascular or uveitic disease).

Before an invasive procedure is considered medically necessary, the policy requires documentation that the patient has had adequate prior medical therapy and, where applicable, laser trabeculoplasty that failed to achieve the target IOP. Failure to respond is defined as the inability to reduce IOP by at least 25% from the IOP measured at diagnosis (target pressure). Exceptions to the prior‑therapy requirement are limited to clearly documented clinical indications — for example, situations where trabeculectomy has already failed or is unlikely to succeed, substantial conjunctival scarring, or other circumstances in which surgery is clinically indicated without additional trials of medications or laser.

CPT and ICD-10 Coding

Aqueous drainage/filtration device CPTCPTCovered

66183

Insertion of anterior segment aqueous drainage device; without extraocular reservoir, external approach

Canaloplasty / transluminal dilation CPTCPTCovered

66174	Transluminal dilation of aqueous outflow canal; without retention of device or stent
66175	Transluminal dilation of aqueous outflow canal; with retention device or stent

ICD-10 codes (partial list) - covered if selection criteria metICD-10Covered

H40.10X0-H40.10X4	Open angle glaucoma, unspecified
H40.1110	Primary open-angle glaucoma, right eye, stage unspecified
H40.1111	Primary open-angle glaucoma, right eye, mild stage
H40.1112	Primary open-angle glaucoma, right eye; moderate stage
H40.1113	Primary open-angle glaucoma, right eye, severe stage
H40.1114	Primary open angle glaucoma, right eye; undetermina
H40.1120	Primary open-angle glaucoma, left eye, stage unspecified
H40.1121	Primary open-angle glaucoma, left eye, mild stage
H40.1122	Primary open-angle glaucoma, left eye, moderate stage
H40.1123	Primary open-angle glaucoma; left eye, severe stage

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Additional ICD-10 codes listedICD-10Covered

H40.1132	Primary open-angle glaucoma, bilateral, moderate stage
H40.1133	Primary open-angle glaucoma, bilateral, severe stage
H40.1134	Primary open-angle glaucoma, bilateral, indeterminate stage
H40.1190	Primary open-angle glaucoma, unspecified eye, stage unspecified
H40.1191	Primary open-angle glaucoma, unspecified eye, mild stage
H40.1192	Primary open-angle glaucoma, unspecified eye, moderate stage
H40.1193	Primary open-angle glaucoma, unspecified eye, severe stage
H40.1194	Primary open-angle glaucoma, unspecified eye, indetermi
H40.11XO-H40.11X4	Primary open angle glaucoma
H40.1290	Low-tension glaucoma, unspecified eye, stage unspecified

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inv-08: IOP reduction threshold

IOP reduction threshold>= 25% reduction from IOP measured at diagnosis (target pressure)

TerminologyThreshold refers to reduction from diagnostic IOP (target pressure)

Use in authorizationDocumentation should demonstrate IOP reduction <25% on medical/laser therapy to justify invasive procedures

Provider Requirements, Prior Authorization, and Documentation

Prior Authorization

Prior Authorization Required

Prior authorization is required for the following CPT codes prior to scheduling procedures: 66174, 66175, 66183, and any CPT codes for Ex-PRESS Mini Glaucoma Shunt or other aqueous drainage/filtration device insertions. Submit supporting clinical documentation demonstrating that medical and/or laser therapy failed to achieve target IOP (see documentation callout).

Affected CPT codes: 66174, 66175, 66183 and codes for Ex-PRESS Mini Glaucoma Shunt or other aqueous drainage device insertions

Documentation Required

Prior Medical and Laser Therapy Must Be Documented

Document prior use of medical therapy and laser trabeculoplasty before surgical consideration. Failure of prior therapy is defined as inability to reduce intraocular pressure (IOP) by at least 25% from the IOP measured at diagnosis (target pressure) or persistent IOP above target despite maximal tolerated medical/laser therapy. Include dates, medications (names, doses, duration), number and type of laser procedures, and objective IOP measurements pre- and post-therapy.

Background

Glaucoma is a group of diseases that damage the optic nerve, most commonly related to elevated intraocular pressure (IOP); left untreated, it can lead to progressive visual field loss and blindness. Invasive surgical procedures and implantable devices aim to improve aqueous outflow and lower IOP sufficiently to prevent further optic nerve injury. This policy frames when such procedures — including aqueous drainage/filtration devices, implantable stents used with cataract surgery, and canaloplasty — meet medical necessity criteria, typically after inadequate response to medications and laser therapy or when surgery is otherwise clinically indicated.

Key Definitions

inv-14: Failure to respond — definition (>=25% IOP reduction not achieved)

DefinitionFailure to respond = inability to reduce intraocular pressure (IOP) by at least 25% from the IOP measured at diagnosis (aka target pressure)

Clinical implicationUsed to determine when invasive glaucoma procedures may be considered medically necessary after inadequate response to medical therapy

Documentation needClinical records must show prior medical/laser therapy and measured IOPs demonstrating <25% reduction to avoid denial

inv-15: Implantable stents (in conjunction with cataract surgery) — definition and contextual usage

DefinitionImplantable stents are used in conjunction with concurrent phacoemulsification (cataract) surgery for targeted IOP reduction in individuals with no significant angle abnormalities

Indication severity