Summary & Overview
HCPCS Q4398: Summit ac, Per Square Centimeter (Add-on)
HCPCS Level II code Q4398 identifies an add-on supply item: Summit ac billed per square centimeter and reported in addition to a primary procedure. Nationally, add-on HCPCS codes like Q4398 matter because they affect total episode costs and require clear documentation of product use and area measured. This code is used across facility and ambulatory settings when the Summit ac product is applied and sized by surface area. Key payers in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare and Medicare.
Readers will find a concise overview of the code’s clinical role, common sites of service, and implications for billing lines. The publication summarizes expected billing contexts, explains how the per-square-centimeter unit influences charge and reimbursement calculations, and highlights typical documentation needs. It also provides comparisons across major payers listed above and outlines areas where payers commonly apply coverage rules or require additional justification. Data not available in the input is noted where specific payer policies, modifiers, associated taxonomies, ICD-10 diagnoses, related codes, and service-line mappings are not provided.
Billing Code Overview
HCPCS Level II code Q4398 denotes Summit ac, per square centimeter (add-on, list separately in addition to primary procedure). This code represents an add-on material supply or device component billed per square centimeter, intended to be reported in addition to a primary procedure when the Summit ac product is used and sized by surface area.
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Service type: Supply/device add-on billed per unit area
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Typical site of service: Ambulatory surgical centers, hospitals, outpatient clinics, and other settings where a primary surgical or procedural service is performed and an additional per-square-centimeter product is applied
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult undergoing treatment with a topical or surface-applied dermatologic product that is billed by area of application. The service is an add-on, reported per square centimeter, and is used when an additional product component (for example, an advanced wound coverage, specialized topical adhesive, or a proprietary acellular component identified as Summit AC) is applied in addition to a primary procedure such as wound debridement, excision, or lesion removal.
A realistic workflow: The patient presents to an outpatient dermatology or wound care clinic with a chronic nonhealing lower-extremity ulcer. The clinician performs wound assessment and primary procedure (debridement and cleansing). After addressing the wound bed, the clinician applies the specialized Summit AC product to the wound surface; the product is measured and billed per square centimeter using the add-on HCPCS Level II code Q4398 in addition to the primary procedure CPT code(s). Documentation includes wound measurements (length × width to calculate cm2), indication for the product, time of application, lot/batch numbers if applicable, and the primary procedure(s) performed during the same encounter. Typical sites of service include outpatient wound care clinics, dermatology offices, ambulatory surgical centers, and hospital outpatient departments.
Common patient factors include chronic diabetic or venous ulcers, post-operative surgical sites requiring advanced topical coverage, or acute traumatic wounds where an adjunctive topical component is used to aid healing or protect the wound after the primary procedure.
Coding Specifications
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