NPPES file of Aug 9, 2026

Karen Yan Ma, O.D.

Optometrist · Sacramento, CA

Karen Yan Ma, O.D. is an optometrist with a practice address in Sacramento, California, and NPI 1639441082, issued on Feb 1, 2012. Check the license (California 14350, as entered in NPPES) with the California board that licenses this profession; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1639441082
Name
Karen Yan Ma
Credential
O.D.
Primary taxonomy
Optometrist 152W00000X
License number
14350 CA
Self-reported in NPPES; status is on the state search
Practice location
5901 Florin RD, Sacramento, CA 95823
Phone
(916) 394-1248
Enumerated
Feb 1, 2012
Record last updated
Jan 18, 2022
Fax
(916) 424-1033
Medicare enrollment
Enrolled (PECOS I20130118000274); accepts Medicare assignment
Medical or professional school
State University Of New York - State College Optometry, 2011
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Verify Karen Yan Ma in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich California board licenses this profession
    Search for license 14350
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Find the California license search

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21% more Medicare Part D claims than the average optometrist in 2024

335 Medicare Part D claims for 136 beneficiaries, against an average of 277 among the 33,128 providers of this specialty who prescribed in Part D. Brand-name drugs were 26% of claims.

  1. Karen Ma335
  2. Specialty average277

Most prescribed

  1. Latanoprost96 claims
  2. Cyclosporine67 claims
  3. Dorzolamide-Timolol44 claims
  4. Timolol Maleate33 claims
  5. Dorzolamide Hcl23 claims
  6. Neomycin-Polymyxin-Dexameth16 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

Bills Medicare through one group practice

  1. Permanente Medical Group IncSanta Rosa, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Karen Yan Ma among 8,308 optometrist records in California

Karen Yan Ma, O.D. is one of 8,308 optometrist records with a practice address in California. 67% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2012, is newer than 64% of them.

  • NPI issued2012 · 64% of these records are older, 34% newer
  • In a Medicare fileYes · 67% of these records are
  • In the CMS Doctors and Clinicians fileYes · 43% of these records are
  • Graduated2011 · median 2008 among the 3,573 with a school on file
  • Record last updated2022 · 67% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 152W00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Optometrist providers in California

There are 8,308 optometrist records in California.

The 8 optometrist records with the nearest ZIP codes

  1. John Alto, O.D.Sacramento, CA 958231780761791
  2. Brett Greenwood, O.D.Sacramento, CA 958231942384110
  3. Maurice Kaz, O.D.Sacramento, CA 958231700880564
  4. Kingman Louie, O.D.Sacramento, CA 958231265522320
  5. Laraine Low, O.D.Sacramento, CA 958231689758856
  6. Albert Mar, O.D.Sacramento, CA 958231447336912
  7. David Ngo, O.D.Sacramento, CA 958231588623268
  8. Matthew Nishio, O.D.Sacramento, CA 958231124041801

Common questions

What is Karen Yan Ma, O.D.'s NPI number?

Karen Yan Ma, O.D.'s National Provider Identifier (NPI) is 1639441082, issued on Feb 1, 2012. An NPI identifies a provider in billing; it is not a license.

Where is Karen Yan Ma, O.D. located?

The NPPES record lists a practice address at 5901 Florin RD, Sacramento, CA, 95823. Phone: (916) 394-1248. Providers update this record themselves, so call before visiting.

How can I verify Karen Yan Ma, O.D.'s license?

NPPES lists California license number 14350, as entered by the provider. Search the California board that licenses this profession; the NPPES record confirms identity only.

How much does Karen Yan Ma, O.D. prescribe under Medicare Part D?

In 2024, Karen Yan Ma, O.D. had 335 Medicare Part D claims for 136 beneficiaries; the average among optometrist prescribers was 277. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.