A9526 Nitrogen n-13 ammonia
What A9526 is
Nitrogen n-13 ammonia, diagnostic, per study dose, up to 40 millicuries
HCPCS Level II long description, CMS October 2026 file. See the A codes page for the full section.
Medicare payment for A9526 (CY2026)
This code has no Physician Fee Schedule rate: Carrier-priced - the Medicare contractor sets the price. It may be paid under a different fee schedule (clinical laboratory, DMEPOS, anesthesia) or not paid at all - check the relevant CMS schedule.
Medically Unlikely Edit (MUE)
Medicare caps A9526 at 2 units per date of service for practitioner claims (MAI 3 - date of service edit (clinical): units above the MUE may pay with documentation on appeal), rationale: Code Descriptor / CPT Instruction. Units above the cap are denied unless the edit's adjudication rules allow an appeal with documentation.
A9526 is bundled into these codes
A9526 appears as a Column 2 code in 10 active edits. Reported with one of these Column 1 codes on the same date of service, A9526 is the code that denies.
| Column 1 code | Short description | Modifier indicator | |
|---|---|---|---|
78451 | Ht muscle image spect sing | 0 | Check pair |
78452 | Ht muscle image spect mult | 0 | Check pair |
78459 | Myocrd img pet single study | 1 | Check pair |
78608 | Brain imaging (pet) | 0 | Check pair |
78811 | Pet image ltd area | 0 | Check pair |
78812 | Pet image skull-thigh | 0 | Check pair |
78813 | Pet image full body | 0 | Check pair |
78814 | Pet image w/ct lmtd | 0 | Check pair |
78815 | Pet image w/ct skull-thigh | 0 | Check pair |
78816 | Pet image w/ct full body | 0 | Check pair |
Data: CMS CY2026 Physician Fee Schedule RVU file (October release, RVU26D) and Medicare NCCI PTP practitioner edits v32.3 (2026 Q4). Verify against the official files before billing or contracting decisions.