Summary & Overview

CPT 0621T: Microinvasive Glaucoma Surgery, Laser Ab Interno

CPT code 0621T denotes a microinvasive glaucoma surgery (MIGS) procedure in which a laser creates holes in the trabecular meshwork via an ab interno approach to enhance aqueous outflow and reduce intraocular pressure. This minimally invasive, laser-based ophthalmic intervention has growing clinical relevance as surgeons seek procedures with lower tissue disruption and faster recovery compared with traditional glaucoma surgeries. Nationally, usage patterns and coverage policies for MIGS procedures can affect access to care for patients with open-angle glaucoma.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the clinical context for CPT code 0621T, typical sites of service, and the service type. The publication also summarizes payer coverage considerations and common billing modifiers encountered with surgical ophthalmology claims. Additionally, the report highlights available benchmarks and policy updates relevant to adoption and reimbursement of laser-based MIGS procedures. Data gaps are noted when input information is not provided.

AetnaBlue Cross Blue ShieldCigna HealthUnitedHealthcareMedicare0621TCPTmicroinvasive glaucoma surgeryMIGSophthalmologylaser surgeryab internointraocular pressure

Billing Code Overview

CPT code 0621T describes a microinvasive glaucoma surgery (MIGS) procedure using a laser to create holes in the eye’s trabecular meshwork via an ab interno approach. The intent of the procedure is to improve aqueous humor outflow through the trabecular meshwork and lower intraocular pressure for patients with glaucoma.

Service type: Surgical ophthalmology procedure (microinvasive glaucoma surgery, laser-based, ab interno approach)
Typical site of service: Ambulatory surgery center or hospital outpatient department; may also be performed in specialized ophthalmology surgical suites depending on facility capabilities.

Clinical & Coding Specifications

Clinical Context

A 68-year-old patient with primary open-angle glaucoma presents with progressive optic nerve cupping and elevated intraocular pressure (IOP) despite maximally tolerated topical medical therapy. The ophthalmologist determines that a minimally invasive surgical approach to improve trabecular outflow is appropriate. The patient undergoes an ab interno microinvasive glaucoma surgery (MIGS) procedure in an ambulatory surgery center or outpatient hospital operating room under monitored anesthesia care or local anesthesia with sedation. The surgeon uses a laser-assisted microincisional technique to create multiple small holes in the trabecular meshwork from inside the anterior chamber to facilitate aqueous humor drainage and reduce IOP. Typical workflow includes preoperative evaluation with visual acuity, IOP measurement, gonioscopy, and informed consent; perioperative antisepsis and topical or regional anesthesia; the ab interno laser trabeculotomy procedure; immediate postoperative assessment in the PACU; and short-term follow-up visits for IOP monitoring, medication adjustment, and wound assessment.

Coding Specifications

Modifier	Description	When to Use
`22`	Increased procedural services	Use when intraoperative work is substantially greater than typical for `0621T` and documentation supports unusual effort or complexity

Taxonomy Code	Specialty	Notes
`207WO0103X`	Ophthalmology	Comprehensive ophthalmologists perform MIGS procedures including ab interno trabeculotomy
`207WG0300X`	Glaucoma Specialist (Ophthalmology - Glaucoma)	Subspecialists in glaucoma commonly perform and manage MIGS interventions
`208100000X`	Ophthalmic Plastic and Reconstructive Surgery	May be involved when combined anterior segment procedures are required
`363L00000X`	Anesthesiology	Provides monitored anesthesia care or general anesthesia for outpatient ophthalmic procedures
`207VP0002X`	Surgical Ophthalmology	Surgeons focused on operative ophthalmic procedures performing MIGS

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`H40.11X0`	Primary open-angle glaucoma, mild stage, unspecified eye	Most common indication for ab interno trabecular microincisional procedures to lower IOP
`H40.11X1`	Primary open-angle glaucoma, mild stage, right eye	Laterality-specific coding for procedural billing and outcome tracking
`H40.11X2`	Primary open-angle glaucoma, mild stage, left eye	Laterality-specific coding for procedural billing and outcome tracking
`H40.1110`	Primary open-angle glaucoma, right eye, mild stage	Precise laterality and stage documentation for `0621T` appropriateness
`H40.1190`	Primary open-angle glaucoma, unspecified eye, moderate stage	Moderate disease may prompt surgical intervention when medical therapy is insufficient
`H40.9`	Glaucoma, unspecified	Used when specific glaucoma type is not documented but a glaucoma procedure like `0621T` is performed
`H42`	Glaucoma secondary to eye trauma	Secondary glaucomas may also be managed with MIGS techniques depending on etiology
`H40.20`	Angle-closure glaucoma, unspecified	Not a typical indication for trabecular meshwork ab interno procedures but included for completeness when angle anatomy is considered

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`66989`	Unlisted procedure, anterior segment of eye	Used when a specific anterior segment procedure accompanying `0621T` is not described by a standard CPT code
`99213`	Office or other outpatient visit for the evaluation and management of an established patient, typically 15 minutes	Preoperative or postoperative clinic visit for IOP check and medication management surrounding `0621T`
`66180`	Trabeculectomy ab externo; fistulization to extraocular sub-Tenon's space using scleral flap	Traditional glaucoma-filtering procedure that may be performed when MIGS is not sufficient; represents an alternative or subsequent surgery
`66982`	Extracapsular cataract removal with insertion of intraocular lens, complex	Cataract surgery performed in the same session as MIGS or in staged combined procedures; lens surgery can be combined with ab interno procedures
`01916`	Anesthesia for intraocular procedures, total intravenous anesthesia; not otherwise specified	Anesthesia services that may be used for patients undergoing `0621T` when general anesthesia is required