Quick answers
- Does Charlton K. Byun accept Medicare assignment?
- Yes. Medicare's clinician data says Charlton K. Byun accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Charlton K. Byun see?
- In 2024, CMS data shows 1,133 Original Medicare patients and 25,484 services for Charlton K. Byun. This counts Original Medicare only and measures volume, not quality.
- What is Charlton K. Byun's NPI number?
- 1225340961. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Charlton K. Byun, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 1,133 |
|---|---|
| Services billed to Medicare | 25,484 |
| Different services or procedures | 111 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Injection, gadoterate meglumine, 0.1 ml (A9575)15,065 services
- Low osmolar contrast material, 300-399 mg/ml iodine concentration, per ml (Q9967)6,129 services
- Injection, methylprednisolone acetate, 1 mg (J1010)2,160 services
- Low osmolar contrast material, 200-299 mg/ml iodine concentration, per ml (Q9966)330 services
- Injection, triamcinolone acetonide, not otherwise specified, 10 mg (J3301)249 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High cholesterol68%
- High blood pressure65%
- Arthritis61%
- Diabetes26%
- Ischemic heart disease22%
- Depression21%
Practice locations
Addresses where Charlton K. Byun is enrolled with Medicare (CMS data updated October 2, 2026).
- 300 Fir StSan Diego, CA 92101 (848) 499‑2600
Group practices
Medicare enrollment lists Charlton K. Byun as a member of this group (CMS data updated October 2, 2026).
- Sharp Rees-Stealy Medical Group Inc884 clinicians in the group
Specialties
- Diagnostic Radiologyprimary
Other radiologists in San Diego
Clinicians with the same Medicare primary specialty in San Diego, CA — not a recommendation.
Other clinicians in Sharp Rees-Stealy Medical Group Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | State University Of New York At Buffalo School Of Medicine |
| Graduation year | 2003 (23 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1225340961 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians