M1323 HCPCS Reimbursement & Policy Benchmarks

HCPCS Level II code M1323 captures a targeted follow-up visit within seven weeks after an intraocular injection to screen for elevated intraocular pressure (IOP) by tonometry, document an IOP >25 mm Hg, and record a plan of care. This code is important nationally because it standardizes reporting for a clinically significant complication of intraocular injections—post-injection IOP elevation—which can require timely monitoring and management to prevent vision loss.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. The publication summarizes payer coverage patterns, common billing modifiers, clinical context, and implications for ambulatory ophthalmology practice.

Readers will learn what this code represents clinically, the typical site and service type associated with it, and which national payers are relevant for coverage considerations. The report also outlines the documentation elements embedded in the code definition (timing within seven weeks, use of tonometry, IOP threshold >25 mm Hg, and a documented plan of care). Data not available in the input is noted where applicable.

Billing Code Overview

HCPCS Level II code M1323 describes follow-up visits within seven weeks after an intraocular injection during which patients are screened for elevated intraocular pressure (IOP) using tonometry, with documentation that IOP exceeded 25 mm Hg and that a plan of care was recorded.

Service type: Post-injection IOP screening and management planning.

Typical site of service: Ophthalmology clinic or ambulatory eye care setting.

Clinical Context

A 68-year-old patient with neovascular age-related macular degeneration receives an intravitreal anti-VEGF injection in the clinic. The patient is scheduled for a follow-up visit within 7 weeks of the injection to be screened for elevated intraocular pressure (IOP). At the follow-up, visual acuity and slit-lamp exam are performed, and IOP is measured with tonometry. The clinician documents an IOP >25 mm Hg in the affected eye, records a plan of care (for example, topical IOP-lowering therapy, monitoring interval, or referral to glaucoma service), and communicates the plan to the patient. The visit occurs in an outpatient ophthalmology clinic or ambulatory surgical center setting and is coded using M1323 to capture the post-injection IOP screening visit with documented elevated IOP and a documented plan of care.

Coding Specifications

Modifier	Description	When to Use
`22`	Increased procedural services	When work required is substantially greater than typically required for this visit due to complex management of elevated IOP after injection.
`23`	Unusual anesthesia

Taxonomy Code	Specialty	Notes
`207RH0000X`	Ophthalmology	Comprehensive ophthalmologists perform intravitreal injections and follow-up IOP screening.
`207RX0201X`	Retina/Vitreous Specialist	Retina specialists administer anti-VEGF injections and manage post-injection IOP events.
`363L00000X`	Optometrist	Optometrists often perform IOP checks and collaborate on management in outpatient settings.
`2080P0208X`	Ophthalmic Plastic and Reconstructive Surgery	Involved when anterior segment or ocular surface complications contribute to elevated IOP.
`207K00000X`	Glaucoma Specialist	Glaucoma specialists manage sustained IOP elevation and determine long-term therapy.

Related Diagnoses

ICD-10 Code	Description	Clinical Relevance
`H35.321`	Exudative age-related macular degeneration, right eye	Neovascular AMD is a common indication for intravitreal anti-VEGF injections and subsequent IOP surveillance.
`H35.322`	Exudative age-related macular degeneration, left eye	Same relevance for injections and post-injection monitoring.
`H40.221`	Primary open-angle glaucoma, mild stage, right eye	Pre-existing glaucoma increases concern for post-injection IOP rise and influences management.
`H40.223`	Primary open-angle glaucoma, moderate stage, right eye	Higher glaucoma severity affects urgency and treatment decisions for elevated IOP.
`H40.9`	Glaucoma, unspecified	Used when glaucoma type is unspecified but elevated IOP requires management after injection.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`99213`	Office or other outpatient visit for the evaluation and management of an established patient, typically 15 minutes	Common code for the follow-up visit when tonometry, examination, and treatment plan for elevated IOP are documented.
`92100`	Serial tonometry and tonography	Codes tonometry measurement of IOP; used when tonometry is separately reportable per payer rules.
`67028`	Intravitreal injection of a pharmacologic agent	Procedure that precedes the `M1323` screening visit; `M1323` documents the post-injection IOP screening within 7 weeks.
`92250`	Fundus photography with interpretation and report	May be performed alongside follow-up visits to document retinal status after injection.
`92012`	Ophthalmologic services: established patient, intermediate, new or established (detailed)	Alternative E/M code used when complexity or time meets requirements for a higher-level visit documenting IOP elevation and management.

OpenPayer

Summary & Overview

HCPCS M1323: Post-Injection IOP Screening and Plan of Care