G9599 HCPCS code: Aortic aneurysm 6.0 cm or greater maximum diameter on centerline formatted ct or minor diameter on axial formatted ct
G9599 is the HCPCS Level II code for aortic aneurysm 6.0 cm or greater maximum diameter on centerline formatted ct or minor diameter on axial formatted ct. Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case.
Code details
| Field | Value |
|---|---|
| Section | G codes — Procedures and professional services (temporary) |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 00 — Not separately priced by Medicare |
| BETOS category | Z2 |
| Added | 2016-01-01 |
| Last action effective | 2016-01-01 |
What changed for G9599
- 2016-01-01: G9599 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code G9599?
G9599 is the HCPCS Level II code for aortic aneurysm 6.0 cm or greater maximum diameter on centerline formatted ct or minor diameter on axial formatted ct. Short descriptor: "Aor ane >=6.0 cm max diam".
Does Medicare cover G9599?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
Related G95 codes
- G9500 — Radiation exposure indices documented in final report for procedure using fluoroscopy
- G9501 — Radiation exposure indices not documented in final report for procedure using fluoroscopy, reason not given
- G9502 — Documentation of medical reason for not performing foot exam (i.e., patients who have had either a bilateral amputation above or below the knee, or both a left and right amputation above or below the knee before or during the measurement period)
- G9503 — Patient taking tamsulosin hydrochloride
- G9504 — Documented reason for not assessing hepatitis b virus (hbv) status (e.g., patient not initiating anti-tnf therapy, patient declined) prior to initiating anti-tnf therapy
- G9505 — Antibiotic regimen prescribed within 10 days after onset of symptoms for documented medical reason
- G9506 — Biologic immune response modifier prescribed
- G9507 — Documentation that the patient is on a statin medication or has documentation of a valid contraindication or exception to statin medications; contraindications/exceptions that can be defined by diagnosis codes include pregnancy during the measurement period, active liver disease, rhabdomyolysis, end stage renal disease on dialysis and heart failure; provider documented contraindications/exceptions include breastfeeding during the measurement period, woman of child-bearing age not actively taking birth control, allergy to statin, drug interaction (hiv protease inhibitors, nefazodone, cyclosporine, gemfibrozil, and danazol) and intolerance (with supporting documentation of trying a statin at least once within the last 5 years or diagnosis codes for myostitis or toxic myopathy related to drugs)
- G9508 — Documentation that the patient is not on a statin medication
- G9509 — Adult patients 18 years of age or older with major depression or dysthymia who reached remission at twelve months as demonstrated by a twelve month (+/-60 days) phq-9 or phq-9m score of less than 5
- G9510 — Adult patients 18 years of age or older with major depression or dysthymia who did not reach remission at twelve months as demonstrated by a twelve month (+/-60 days) phq-9 or phq-9m score of less than 5. either phq- 9 or phq-9m score was not assessed or is greater than or equal to 5
- G9511 — Index event date phq-9 or phq-9m score greater than 9 documented during the twelve month denominator identification period
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Next steps
- Run a reimbursement report for a device billed under G9599
- Watch G9599 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for G9599
Sources: CMS HCPCS Level II release October 2025; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.