CurrentBlue Cross Blue Shield - MassachusettsPolicy 372

Canaloplasty and Viscocanalostomy — Coverage Criteria

This policy governs coverage of canaloplasty and viscocanalostomy for reducing intraocular pressure in individuals with glaucoma for Blue Cross Blue Shield Massachusetts members across commercial and Medicare product lines.

Policy Summary

PayerBlue Cross Blue Shield - Massachusetts

PolicyCanaloplasty and Viscocanalostomy — Coverage Criteria

Policy CodePolicy 372

Change TypeNo material change

Effective Date

Next Review Date

Key ActionObtain inpatient precertification/preauthorization when canaloplasty is performed inpatient; ensure medical necessity criteria are documented for listed procedure codes.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

372Payer policy identifier

2 codesProcedure codes listed

MultipleDiagnosis codes listed

MultipleRandomized trials referenced

3–6 yr+Long-term outcomes

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Coverage Criteria

Canaloplasty — Covered with criteria

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

Canaloplasty medical necessity: 1) Individual has chronic primary open-angle glaucoma; 2) Individual is not a candidate for any other IOP-lowering procedure (e.g., trabeculectomy or glaucoma drainage implant) due to a high risk for complications; AND 3) Medical therapy has failed to adequately control intraocular pressure.

From policy statements

Investigational / Not covered

Not covered / investigational statements

Investigational uses: Canaloplasty is considered investigational under all other conditions, including angle-closure glaucoma; Viscocanalostomy is considered investigational.

From policy statements

The policy states that canaloplasty may be considered MEDICALLY NECESSARY to reduce intraocular pressure in individuals with chronic primary open-angle glaucoma only when all listed criteria are met, including that the patient is not a candidate for other IOP-lowering procedures (eg, trabeculectomy or glaucoma drainage implant) because of high risk for complications, and that medical therapy has failed to adequately control IOP. The same policy language specifies that canaloplasty is investigational under all other conditions, including angle-closure glaucoma, and that viscocanalostomy is considered investigational.

No additional explicit exclusions for canaloplasty or viscocanalostomy are provided in the listed reference sections. The references cited include guideline and evidence reports but do not identify other procedure-specific exclusion statements in the excerpts provided.

Per the policy statements, viscocanalostomy is considered investigational. Because it is classified as investigational in this policy, it is not a covered or recommended procedure for the indications addressed here.

In the supplied reference list and excerpts there are no explicit 'not medically necessary' declarations beyond the policy's investigational classifications; the references themselves do not add further 'not medically necessary' statements in the provided excerpts.

Coding

Covered CPT Codes (conditional)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 paired with CPT and criteria)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 & Operational Notes

Prior Authorization

Prior authorization not specified

Prior authorization not specified — The policy references and excerpts do not state a universal prior authorization requirement for canaloplasty when performed outpatient. For many products (Commercial PPO, Indemnity, Medicare HMO BlueSM, Medicare PPO BlueSM) outpatient prior authorization is noted as not required; however, requirements can vary by product and member contract.

Outpatient prior authorization generally not required for: Commercial PPO and Indemnity; Medicare HMO BlueSM; Medicare PPO BlueSM (per referenced excerpts).
Precertification/preauthorization IS REQUIRED if the procedure is performed inpatient.

Prior Authorization

Prior authorization summary

Prior authorization summary — Prior authorization rules differ by product and setting. Inpatient procedures require precertification/preauthorization. Outpatient prior authorization generally is not required for several products per the reference excerpts, but providers must verify requirements based on the member's specific product and contract prior to scheduling.

Inpatient: precertification/preauthorization is required.

Background

Glaucoma is characterized by impaired aqueous humor outflow leading to elevated intraocular pressure (IOP) and is a leading cause of irreversible vision loss. Surgical intervention is considered when target IOP cannot be achieved with medical therapy. Canaloplasty and viscocanalostomy are nonpenetrating procedures intended to restore conventional outflow by dilating Schlemm's canal; canaloplasty uses circumferential viscodilation and tensioning of the canal to lower IOP, while viscocanalostomy is an earlier nonpenetrating variant. The policy emphasizes use of canaloplasty only for chronic primary open-angle glaucoma when other surgical options are not appropriate and medical therapy has failed.

Definitions

Canaloplasty (definition)

DefinitionCanaloplasty involves circumferential dilation and tensioning of Schlemm canal, typically using an illuminated microcatheter (iTrack) to dilate the canal and place a tensioning suture, aiming to open the entire length of the canal.

PurposeRestores conventional aqueous outflow to lower intraocular pressure in open-angle glaucoma.

Technique detailsUses an illuminated microcatheter to access and viscodilate the canal and to pass and tension a suture loop between the inner canal wall and trabecular meshwork.

Clinical noteAttempts to open the entire Schlemm canal rather than a single section, differing from viscocanalostomy.

Viscocanalostomy (definition)

DefinitionViscocanalostomy is a nonpenetrating variant that unroofs and dilates the Schlemm canal using high-viscosity viscoelastic (eg, sodium hyaluronate) to open the canal and create a passage to a scleral reservoir.

Policy Summary

PayerBlue Cross Blue Shield - Massachusetts

PolicyCanaloplasty and Viscocanalostomy — Coverage Criteria

Policy CodePolicy 372

Change TypeNo material change

Effective Date

Next Review Date

Key ActionObtain inpatient precertification/preauthorization when canaloplasty is performed inpatient; ensure medical necessity criteria are documented for listed procedure codes.

SourceLink

On This Page

Outpatient: requirements vary by product; some products list outpatient prior authorization as not required — verify member contract.

Billing Rule

Coding and documentation

Coding and documentation — Providers must report services using current industry-standard procedure, revenue, and diagnosis codes, and include applicable modifiers. Inclusion of codes in the policy does not guarantee coverage — coverage depends on meeting the documented medical necessity criteria and the member's contract.

Report using up-to-date CPT/HCPCS/ICD-10 and revenue codes, with modifiers where applicable.
The listed codes are informational; coverage requires meeting the policy medical necessity criteria and checking member benefits.

Documentation Required

Documentation requirements not specified

Documentation requirements not specified in references — The provided source excerpts do not list specific documentation elements beyond meeting the medical necessity criteria and standard coding requirements. Providers should retain clinical records demonstrating failure of medical therapy, candidacy rationale (eg, high risk for complications with alternative procedures), and procedure details to support medical necessity.

No explicit additional documentation checklist is provided in the reference excerpts.
Retain clinical documentation: prior treatments and responses, rationale for canaloplasty over alternatives, operative report, and relevant diagnostic findings.

Technique detailsUnroofs the canal without penetrating the trabecular meshwork or anterior chamber and uses viscoelastic to dilate the canal.

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

Relationship to canaloplastyPrecursor to canaloplasty; viscocanalostomy dilates a section of canal whereas canaloplasty aims to open the entire canal circumference.

Canaloplasty (surgical procedure)

ProcedureSurgical circumferential viscodilation and tensioning of Schlemm's canal using a flexible microcatheter to lower intraocular pressure in open-angle glaucoma.

DeviceTypically performed with an illuminated microcatheter (iTrack) to dilate the canal and facilitate placement of a tensioning suture.

IndicationUsed as a nonpenetrating alternative to filtering procedures in patients with chronic primary open-angle glaucoma when criteria are met.

Clinical outcomesMultiple randomized trials and long-term studies report outcomes up to several years after the procedure.

Ab‑interno canaloplasty (definition)

DefinitionAb‑interno canaloplasty is a minimally invasive, from-inside-the-eye approach to canaloplasty that can be performed standalone or combined with cataract (phacoemulsification) surgery.

Combined proceduresFrequently performed in combination with trabeculotomy or cataract surgery (phacoemulsification) in contemporary studies (eg, GEMINI study).

PurposeAims to dilate Schlemm's canal and enhance outflow using an ab‑interno approach with reduced tissue disruption compared with ab‑externo techniques.

EvidenceRecent clinical studies and real‑world reports document 12‑ to 36‑month outcomes for ab‑interno canaloplasty combined with other procedures.