Billing code 36228: Intracranial catheterizationMedicare rate & RVUs in Guam
Reports selective catheter placement and angiography of an additional intracranial branch, such as an anterior or middle cerebral artery branch, during cerebral angiography.
Medicare pays $1,706.65 for 36228 in the office in Guam (Hawaii, Guam). Which amount applies depends on the service address.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 36228 covers
This add-on describes selective catheterization of an additional second- or third-order intracranial branch within a vascular family, with angiography of the selected vessel and its supplied intracranial branches when performed. Neurointerventional physicians and other physicians performing diagnostic cerebral angiography may use it when they advance the catheter beyond an internal carotid or vertebral artery into a qualifying intracranial branch. The service is commonly performed in a hospital angiography suite.
Report 36228 with the applicable primary angiography service, commonly 36224 for an internal carotid artery study or 36226 for a vertebral artery study; it is not reported alone. Documentation should identify the vascular family, the additional branch selectively catheterized, and the angiography performed. Report the code for each qualifying additional branch. It is an add-on paid within the primary procedure's global period. For a bilateral procedure reported with modifier 50, CMS pays 150% of the single-procedure amount.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
36228 in Hawaii, Guam
| Payment locality | Office | Facility |
|---|---|---|
| Hawaii, Guam | $1,706.65 | $209.99 |
How the 36228 rate is calculated
Each of 36228’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 36228
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 4.14Practice expense 40.57Malpractice 1.43
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 36228
The CMS indicators that decide how 36228 is paid alongside other services.
CMS payment indicators · 36228
Intracranial catheterization
| Rule | CMS value | What it means |
|---|---|---|
| Global period | ZZZ | Add-on code: falls within the primary procedure’s global period. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 1 | Bilateral with modifier 50 pays 150% of the fee schedule amount. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 50 · payment effect
With and without the modifier
36228 without 50 · national office
$1,541.12
Intracranial catheterization
36228-50 · Bilateral: 150%
$2,311.68
Both sides on one line with modifier 50 are paid at 150% of the fee schedule amount (subject to multiple-procedure rules with other procedures).
36228 compared with similar codes
Compare codes
36228 vs 36224 vs 36226 vs 36227: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 36224Carotid angiography
- 36224 reports the primary internal carotid angiography service. Use 36228 for an additional selective catheter placement into a qualifying intracranial branch within that vascular family.
- 36226Vertebral angiography
- 36226 reports the primary vertebral artery angiography service. Add 36228 when an additional qualifying intracranial branch in that vascular family is selectively catheterized.
- 36227External carotid angiography
- 36227 concerns selective external carotid catheterization and imaging; 36228 concerns an additional intracranial branch within a vascular family.
36228 billing questions
When is 36228 reported instead of 36224 or 36226?
Use 36224 or 36226 for the applicable internal carotid or vertebral artery angiography service. Add 36228 when the catheter is selectively advanced into an additional qualifying intracranial branch within that vascular family.
Can 36228 be billed by itself?
No. It is an add-on code and must be reported with the applicable primary procedure, commonly 36224 or 36226.
How many units of 36228 should be reported?
Report a unit for each qualifying additional second- or third-order intracranial branch selectively catheterized. The record should identify each branch and the angiography performed.
What supports reporting 36228?
Document the parent vascular family, the specific additional intracranial branch entered selectively, and the imaging performed. Imaging branches from a catheter that remains in the internal carotid or vertebral artery alone does not establish this additional selective catheterization.
How is bilateral 36228 handled?
For a bilateral procedure reported with modifier 50, CMS pays 150% of the single-procedure amount. The add-on must still be reported with its applicable primary procedure.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
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