DR. JOAN JOONSUN RYOO MD, MSHS
NPI 1699854596
Radiology - Therapeutic Radiology in Los Angeles, CA
About Dr. Joan Joonsun Ryoo Md, Mshs NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. JOAN JOONSUN RYOO MD, MSHS (NPI 1699854596) is an individual therapeutic radiology provider in Los Angeles, California, licensed in California (A98329) and active in the NPI registry since November 2006. She is enrolled in Medicare PECOS and is a graduate of Harvard Medical School (2004).
NPPES Registry Identity
Specialties & Licenses 2
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Dr. Joan Joonsun Ryoo Md, Mshs is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignment
Medicare enrollment records show Joan Ryoo reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Los Angeles, CA 90027
- Reassigned Medicare billing, California enrollment
- Also billed through NPI 1396287082 (California)
- 13,921 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
LOS ANGELES, CA 90027
LOS ANGELES, CA 90027
LOS ANGELES, CA 90027
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Joan Ryoo's NPI number?
The NPI number for Joan Ryoo is 1699854596. It was assigned to this individual provider in the NPPES registry on November 3, 2006.
Where is Joan Ryoo located?
Joan Ryoo practices at 4950 W Sunset Blvd Second Floor, Los Angeles, CA 90027. The listed phone number is (323) 783-2841.
What is Joan Ryoo's specialty?
The primary specialty registered for this NPI is Radiology, specializing in Therapeutic Radiology, with taxonomy code 2085R0203X.
Is Joan Ryoo enrolled in Medicare?
Yes. Joan Ryoo is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organization bills Medicare for Joan Ryoo's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Joan Ryoo reassigns Medicare benefits to Southern California Permanente Medical Group (Los Angeles, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Joan Ryoo's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Joan Ryoo was last updated on December 1, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Dr. Joan Joonsun Ryoo, MD, MSHS · NPI 1699854596
Therapeutic Radiology physician in Los Angeles, California. Individual provider, active in the CMS NPPES registry since November 3, 2006.
## Identity
- **NPI:** 1699854596 (Entity type: Individual)
- **Enumerated:** November 3, 2006
- **Primary specialty:** Radiology - Therapeutic Radiology · taxonomy 2085R0203X
- **State license:** A98329 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 4950 W SUNSET BLVD, SECOND FLOOR, Los Angeles, CA 90027-5822
- **Phone:** (323) 783-2841
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** Southern California Permanente Medical Group (NPI 1134151657, Los Angeles, CA), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Harvard Medical School, class of 2004
## Record status
- **NPPES last updated:** December 1, 2021
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Source: [NPI Profile](https://npiprofile.com/npi/1699854596) · Data from the CMS NPPES public registry.