CurrentBlue Cross Blue Shield - Rhode IslandPolicy N/A

Medical Coverage Policy Aqueous Shunts and Stents for Glaucoma

Defines medical necessity and coverage positions for ab externo aqueous shunts and ab interno aqueous stents (including implantation with cataract surgery) for treatment of glaucoma for Medicare Advantage and Commercial products, and provides related coding guidance.

Policy Summary

PayerBlue Cross Blue Shield - Rhode Island

PolicyMedical Coverage Policy Aqueous Shunts and Stents for Glaucoma

Policy CodePolicy N/A

Change TypeNo material change

Effective Date01/01/2020

Next Review DateN/A

Key ActionProvider must document that medical therapy failed to adequately control intraocular pressure for procedures to be considered medically necessary.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes identified in this update.

2Medically Necessary Categories (ab externo; ab interno with failed therapy)

1Conditional/with cataract surgery (1-2 stents)

2Not covered categories (ab externo when IOP controlled; ab interno other indications)

Coverage Summary

Defines medical necessity and coverage positions for ab externo aqueous shunts and ab interno aqueous stents (including implantation with cataract surgery) for treatment of glaucoma for Medicare Advantage and Commercial products. Effective date: 01/01/2020; Policy last reviewed: 12/15/2021. Coverage stance: mixed — ab externo shunts and certain ab interno stent uses are described as medically necessary when criteria are met, some ab interno stent uses are conditionally covered with cataract surgery, and other uses are not covered or are considered not medically necessary.

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Medical‑Necessity Criteria

Medically Necessary - Ab externo aqueous shunts

Insertion of ab externo aqueous shunts approved by the U.S. FDA may be considered medically necessary when:

ALL of the following

Device is an ab externo aqueous shunt approved by the U.S. Food and Drug Administration
Used as a method to reduce intraocular pressure in patients with glaucoma where medical therapy has failed to adequately control intraocular pressure

Medically Necessary - Ab interno aqueous stents (Medicare Advantage & Commercial)

Insertion of ab interno aqueous stents approved by the U.S. FDA may be considered medically necessary when:

ALL of the following

Device is an ab interno aqueous stent approved by the U.S. Food and Drug Administration
Used as a method to reduce intraocular pressure in patients with glaucoma where medical therapy has failed to adequately control intraocular pressure

Medically Necessary - Ab interno stents with cataract surgery

Implantation in conjunction with cataract surgery may be considered medically necessary when ALL of the following are met:

ALL of the following

Implantation of 1 or 2 FDA-approved ab interno stents
Performed in conjunction with cataract surgery
Patient has mild-to-moderate open-angle glaucoma treated with ocular hypotensive medication

Not covered / Not medically necessary - Other uses

Use is not covered / considered not medically necessary for the following indications:

Use of an ab externo aqueous shunt for conditions including patients with glaucoma when intraocular pressure is adequately controlled by medications

Not covered for Medicare Advantage Plans; considered not medically necessary for Commercial Products

Use of ab interno stents for all other indications not specified as medically necessary

Not covered for Medicare Advantage Plans; considered not medically necessary for Commercial Products

Coding Guidance

Covered procedure codes (when used with a covered ICD-10 diagnosis)CPTCovered

66183	Insertion of anterior segment aqueous drainage device, without extraocular reservoir; external approach (covered when used with a listed ICD-10 diagnosis).
0191T	Insertion of anterior segment aqueous drainage device, without extraocular reservoir; internal approach, into the trabecular meshwork; initial insertion. (Code deleted 12/31/2021; listed in policy coding history).
0253T	Insertion of anterior segment aqueous drainage device, without extraocular reservoir; internal approach, into the suprachoroidal space (covered when used with a listed ICD-10 diagnosis).
0376T	Insertion of anterior segment aqueous device; without extraocular reservoir; internal approach, into the trabecular meshwork; each additional device insertion. (Code deleted 12/31/2021; listed as additive code in policy).
0449T	Insertion of aqueous drainage device, without extraocular reservoir; internal approach, into the subconjunctival space; initial device (covered when used with a listed ICD-10 diagnosis).
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; covered when used with a listed ICD-10 diagnosis).
0474T	Insertion of anterior segment aqueous drainage device, with creation of intraocular reservoir; internal approach, into the supraciliary space (covered when used with a listed ICD-10 diagnosis).
0671T	Insertion of anterior segment aqueous drainage device into the trabecular meshwork, without external reservoir; and without concomitant cataract removal, one or more (New code effective 01/01/2022; covered when used with a listed ICD-10 diagnosis).

Supporting ICD-10 diagnosis codes (may support medical necessity)ICD-10Covered

H40.10X0	Primary open-angle glaucoma unspecified stage, right eye (listed as an ICD-10 code that may support medical necessity).
H42	Glaucoma in diseases classified elsewhere / unspecified codes as listed in policy (listed as an ICD-10 code that may support medical necessity).

Some procedure codes have been deleted or added over time. For example, CPT codes 0191T and 0376T are noted as deleted 12/31/2021 in the coding descriptions, and a new code 0671T is listed as New Code effective 1/01/2022 for insertion of an anterior segment aqueous drainage device into the trabecular meshwork without external reservoir when performed without concomitant cataract removal.

Provider Actions & Billing Rules

Documentation Required

Document prior failure of medical therapy

Document that medical therapy failed to adequately control intraocular pressure for procedures to be considered medically necessary.

Billing Rule

Link procedure codes to covered ICD-10 diagnosis

Listed procedure CPT/TM codes are covered only when used with a covered ICD-10 diagnosis code as specified in the policy. Covered only when used with a covered ICD-10 diagnosis code as specified in the policy.

66183
0191T
0253T
0376T
0449T
0450T
0474T
0671T
Covered only when used with a covered ICD-10 diagnosis code as specified in the policy.

Background & Evidence

Glaucoma surgery aims to lower intraocular pressure (IOP) when medications cannot achieve target IOP. Ab externo aqueous shunts (examples cleared by the FDA include the Ahmed, Baerveldt, Molteno, and EX-PRESS mini-shunt) divert aqueous humor via an external approach and are primarily indicated for failed medical or surgical therapy. Ab interno microstents/MIGS (examples include the iStent, CyPass, XEN, and Hydrus microstent) are less invasive, inserted from inside the eye into pathways such as the trabecular meshwork, suprachoroidal, or subconjunctival spaces, and have been investigated both as standalone procedures and as an adjunct to cataract surgery (particularly for mild-to-moderate open-angle glaucoma treated with ocular hypotensive medication).

Definitions

ab externoInsertion of shunt from outside the eye (external approach).

ab internoInsertion of stent from inside the eye (internal approach), often via the trabecular meshwork or subconjunctival/suprachoroidal spaces.

MIGSMinimally invasive glaucoma surgeries using microscopic equipment and smaller incisions to reduce surgical manipulation.

Evidence includes randomized controlled trials and observational studies comparing microstents (single vs multiple stents and stents versus other procedures) and trials of ab externo shunts; however, the policy states that evidence is insufficient to determine the effects of microstents for some indications despite several RCTs and observational studies being available.

Policy Summary

PayerBlue Cross Blue Shield - Rhode Island

PolicyMedical Coverage Policy Aqueous Shunts and Stents for Glaucoma

Policy CodePolicy N/A

Change TypeNo material change

Effective Date01/01/2020

Next Review DateN/A

Key ActionProvider must document that medical therapy failed to adequately control intraocular pressure for procedures to be considered medically necessary.

SourceLink

On This Page

OpenPayer

Medical Coverage Policy Aqueous Shunts and Stents for Glaucoma

Coverage Summary

Medical‑Necessity Criteria

Coding Guidance

Provider Actions & Billing Rules

Background & Evidence

Revision History