CurrentBlue Cross Blue Shield - MassachusettsPolicy 372

Canaloplasty and Viscocanalostomy for Open-Angle Glaucoma

This policy governs coverage and prior authorization requirements for canaloplasty and viscocanalostomy procedures to reduce intraocular pressure in members with glaucoma. It applies to Commercial and Medicare plan members of Blue Cross Blue Shield Massachusetts as described.

Policy Summary

PayerBlue Cross Blue Shield - Massachusetts

PolicyCanaloplasty and Viscocanalostomy for Open-Angle Glaucoma

Policy CodePolicy 372

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionObtain precertification/preauthorization when canaloplasty is performed inpatient; outpatient prior authorization is generally not required for many Commercial and Medicare plans.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

66174,66175CPT codes listed for canaloplasty

H40.11xICD-10 codes listed

InvestigationalViscocanalostomy stance

RequiredInpatient precert

Not required (most)Outpatient prior auth

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Coverage Criteria

Medical Necessity Criteria for Canaloplasty

Canaloplasty may be considered MEDICALLY NECESSARY when ALL of the following are met:

Eligibility: Member has chronic primary open-angle glaucoma

ICD-10 codes listed in coding module apply

Prior therapy: Medical therapy has failed to adequately control intraocular pressure (IOP)

Document prior medical therapy trials in the chart

Surgical candidacy: Individual is not a candidate for any other IOP-lowering procedure (eg, trabeculectomy or glaucoma drainage implant) due to a high risk for complications

Specify reason(s) the member is at high risk for complications from alternative procedures

Canaloplasty may be considered MEDICALLY NECESSARY to reduce intraocular pressure in individuals with chronic primary open‑angle glaucoma when all of the following are met: medical therapy has failed to adequately control IOP, and the individual is not a candidate for other IOP‑lowering procedures (eg, trabeculectomy or glaucoma drainage implant) due to high risk for complications. Canaloplasty is considered INVESTIGATIONAL under all other conditions, including angle‑closure glaucoma.

No explicit coverage exclusions are stated in the listed reference sections beyond the policy statements themselves. The references provide clinical and outcomes literature (including studies and systematic reviews) but do not add separate coverage exclusions to the policy language.

Viscocanalostomy is designated as INVESTIGATIONAL in this policy. The document notes viscocanalostomy separately from canaloplasty and indicates it is not considered medically necessary under the coverage stance described.

Within the provided reference sections there are no explicit statements labeling additional procedures or situations as 'not medically necessary'; the references focus on clinical studies and systematic reviews rather than issuing further not‑medically‑necessary rulings.

Coding

Covered CPT Codes (when medical necessity met)CPTCovered

66174	Transluminal dilation of aqueous outflow canal (eg, canaloplasty); without retention of device or stent.
66175	Transluminal dilation of aqueous outflow canal (eg, canaloplasty); with retention of device or stent.

ICD-10 Diagnosis Codes (medically necessary when criteria met)ICD-10

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, indeterminate stage.
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.
H40.1124	Primary open-angle glaucoma, left eye, indeterminate stage.

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Provider Actions & Authorization

Prior Authorization

Prior Authorization Required for Inpatient Services

For services described in this policy, precertification/preauthorization is REQUIRED if the procedure is performed inpatient. If inpatient authorization is not obtained when required, claims may be denied or subject to payment delay.

Applicable setting: Inpatient
Action: Obtain precertification/preauthorization prior to admission

Prior Authorization

Outpatient Prior Authorization Guidance

For outpatient settings, prior authorization is generally not required for Commercial Managed Care (HMO and POS), Commercial PPO and Indemnity, Medicare HMO Blue SM, and Medicare PPO Blue SM per plan rules noted below; however, providers should confirm member-specific benefit and authorization requirements before scheduling services.

Commercial Managed Care (HMO and POS), Outpatient = Prior authorization is not required
Commercial PPO and Indemnity, Outpatient = Prior authorization is not required

Background

Glaucoma is a group of optic neuropathies in which elevated intraocular pressure (IOP) is a major risk factor for progressive vision loss. Impaired aqueous humor outflow through the trabecular meshwork and Schlemm canal contributes to elevated IOP; surgical procedures such as canaloplasty and viscocanalostomy aim to improve outflow and lower IOP. Canaloplasty involves dilation and tensioning of Schlemm canal (often using an illuminated microcatheter and suture) to open the canal and decrease resistance to aqueous outflow.

Definitions

Canaloplasty — definition and typical technique (microcatheter, suture tensioning)

DefinitionCanaloplasty: surgical dilation and tensioning of Schlemm canal using an illuminated microcatheter (eg, iTrack) and passage of a suture loop to tension the canal, with the goal of opening the entire canal length.

Typical techniqueAb externo or ab interno approaches may be used; the iTrack™ illuminated microcatheter is advanced circumferentially to dilate the canal and deliver a suture loop which is then tensioned to maintain canal patency.

Devices mentionediTrack™ illuminated microcatheter; OMNI® Surgical System (also dilates Schlemm canal and collector channels).

Relation to viscocanalostomyCanaloplasty evolved from viscocanalostomy but attempts to open the entire length of Schlemm canal rather than a single section.

MIGS classificationAb interno canaloplasty (ABiC) is considered a minimally invasive glaucoma surgery (MIGS); ab externo canaloplasty is not considered a MIGS.

Policy Summary

PayerBlue Cross Blue Shield - Massachusetts

PolicyCanaloplasty and Viscocanalostomy for Open-Angle Glaucoma

Policy CodePolicy 372

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionObtain precertification/preauthorization when canaloplasty is performed inpatient; outpatient prior authorization is generally not required for many Commercial and Medicare plans.

SourceLink

On This Page

Medicare HMO Blue SM, Outpatient = Prior authorization is not required

Medicare PPO Blue SM, Outpatient = Prior authorization is not required

Documentation Required

No Specific Documentation Requirements Provided

No documentation requirements are provided in the policy reference sections. Providers must still maintain comprehensive clinical records demonstrating that medical necessity criteria are met (eg, prior medical therapy failure, clinical findings) and should supply those records on request.

No explicit documentation checklist provided in this policy section
Retain and be prepared to submit clinical records supporting medical necessity (medication trials, IOP measurements, prior procedures)

Step Therapy

No Step Therapy Requirements Specified

No step therapy requirements are listed in the policy references. There is an expectation that medical therapy has failed to adequately control IOP before canaloplasty is considered medically necessary, but no formal step-therapy protocol is specified.

Policy requirement: Medical therapy must have failed to adequately control IOP prior to considering canaloplasty
No formal step-therapy or sequencing rules enumerated in the reference sections

Billing Rule

Coding and Claim Submission

Providers should report services using current procedure and diagnosis codes. Relevant codes include CPT 66174 and 66175 and the listed ICD-10 diagnosis codes for primary open-angle glaucoma when medical necessity criteria are met.

Covered CPT codes (informational): 66174, 66175
ICD-10 codes: H40.11xx series for primary open-angle glaucoma (see policy for full list)
Use most up-to-date procedure, revenue, and diagnosis codes and include modifiers where applicable

Viscocanalostomy — definition and technique (viscoelastic dilation of Schlemm canal)

DefinitionViscocanalostomy: a nonpenetrating deep sclerectomy variant that unroofs and dilates Schlemm canal without penetrating the trabecular meshwork or anterior chamber.

TechniqueA high-viscosity viscoelastic solution (eg, sodium hyaluronate) is used to dilate and open the Schlemm canal and create a passage from the canal to a scleral reservoir.

Intended benefitProposed to lower intraocular pressure while avoiding bleb-related complications associated with penetrating filtration procedures like trabeculectomy.

Relation to canaloplastyViscocanalostomy is the precursor to canaloplasty; canaloplasty subsequently added circumferential dilation and suture tensioning techniques.

NICE guidance — references to NICE guidance on canaloplasty and glaucoma management

NICE ab externo guidanceNICE IPG591: Ab externo canaloplasty for primary open-angle glaucoma (2017).

NICE ab interno guidanceNICE IPG745: Ab interno canaloplasty for open-angle glaucoma (2022).

NICE glaucoma management guidanceNICE NG81: Glaucoma: diagnosis and management (2022).

Use in policy contextNICE guidance documents are referenced for contextual considerations on canaloplasty techniques (ab externo and ab interno) and glaucoma management.