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AI (THERESA) DIEM NGUYEN O.D.
NPI 1508857533
Optometrist in San Diego, CA

Active since October 31, 2005PECOS EnrolledAccepts Medicare Assignment
80.31/100
CMS Quality Rating
6945 EL CAJON BLVD, SAN DIEGO, CA 92115(619) 697-4600(619) 464-5526 Get Directions Write a Review

NPPES record last updated: February 28, 2013. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About Ai (theresa) Diem Nguyen O.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

AI (THERESA) DIEM NGUYEN O.D. (NPI 1508857533) is an individual optometrist in San Diego, California, licensed in California (OPT11481) and active in the NPI registry since October 2005. She is enrolled in Medicare PECOS and is a graduate of Pennsylvania College Of Optometry (2000).

NPPES Registry Identity

NPI1508857533
Entity TypeIndividualFemale
Primary Taxonomy152W00000X
Provider Legal NameAI (THERESA) DIEM NGUYENCredential: O.D.
Location Address6945 EL CAJON BLVDSan Diego, CA 92115-1754
Mailing Address6945 El Cajon BlvdSan Diego, CA 92115-1754 · (619) 697-4600 · Fax (619) 464-5526
Phone(619) 697-4600
Fax(619) 464-5526
Sole ProprietorNo
Medical School CMSPennsylvania College Of OptometryGraduated 2000
Enumeration DateOctober 31, 2005
Last NPPES UpdateFebruary 28, 2013
✔ NPI 1508857533 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyOptometristEye and Vision Services Providers
Taxonomy Code152W00000X
License✔ Licensed in CA · OPT11481
Definition
Doctors of optometry (ODs) are the primary health care professionals for the eye. Optometrists examine, diagnose, treat, and manage diseases, injuries, and disorders of the visual system, the eye, and associated structures as well as identify related systemic conditions affecting the eye. An optometrist has completed pre-professional undergraduate education in a college or university and four years of professional education at a college of optometry, leading to the doctor of optometry (O.D.) degree. Some optometrists complete an optional residency in a specific area of practice. Optometrists are eye health care professionals state-licensed to diagnose and treat diseases and disorders of the eye and visual system.
6945 EL CAJON BLVD, San Diego, CA 92115
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Other Identifiers 3

MedicaidGR0052930CA
Medicare ID-Type UnspecifiedW8162CA
OtherOPT11481CA · State License Number

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Louisiana, Providence Health Plan.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Ai (theresa) Diem Nguyen O.d. 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.

PECOS PAC ID1951331156
PECOS Enrollment IDI20050817000646
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency– Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 6

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient complete exam of visual system 92014
An established patient complete exam of the visual system involves a thorough check of your eyes and vision. It assesses eye health, checks for diseases, and measures your ability to see clearly at different distances. It's a routine, non-invasive procedure.
41 services41 patients
New patient complete exam of visual system 92004
A new patient complete exam of the visual system is a thorough evaluation of your eyes and vision. It checks for any potential issues and assesses overall eye health. It includes tests for visual acuity, eye movement, and light response.
35 services35 patients
Established patient problem focused exam of visual system 92012
This is a routine check-up for existing patients focusing on the visual system. It involves examining your eyes to detect any potential issues or changes in your vision. It's a crucial part of maintaining good eye health.
35 services34 patients
Exam of visual field with extended testing 92083
An extended visual field exam is a detailed test to evaluate your peripheral (side) vision. It helps to detect any potential blind spots which may not be noticeable in daily life. These could be caused by eye diseases like glaucoma, or neurological conditions.
16 services15 patients
Imaging of optic nerve 92133
Imaging of the optic nerve is a non-invasive procedure that captures detailed pictures of your optic nerve. It helps doctors assess eye health, particularly for conditions like glaucoma. It's painless, quick, and uses safe technology like MRI or OCT (Optical Coherence Tomography).
14 services13 patients
Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more 99212
This is a routine check-up for patients who have previously seen the doctor. During this 10-19 minute visit, the doctor will review your health status, discuss any concerns, and manage ongoing treatments or medications. It's a chance to ensure your health is on track.
13 services13 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 92115 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$140.22 typical visit price
range $62.10 – $184.71
Typical copayment $35.05 (range $15.52 – $46.17)
Most-billed visit code 99204
Established Patient
$76.87 typical visit price
range $20.62 – $151.42
Typical copayment $19.21 (range $5.15 – $37.85)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

80.31/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality97.77
Improvement Activities40
Cost20.67

Other Providers at the Same Location NPPES 16

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

BRENDA J SWIDERSKI O.D.
Optometrist
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 697-4600
SHARON MICHELLE DYER
Optometrist
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 697-4600
RETINA INSTITUTE OF CALIFORNIA MEDICAL GROUP, A CALIFORNIA MEDICAL PAR
Ophthalmology
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 697-4600
YASMIN AGHA KOUCHAK O.D
Optometrist
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (800) 898-2020
DR. DEBRA LYNN MCINTYRE O.D.
Optometrist
6945 EL CAJON BLVD, 6945 EL CAJON BLVD.
SAN DIEGO, CA 92115
San Diego County (619) 697-4600
DR. SARJAN H. PATEL M.D.
Ophthalmology
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 723-1292
BARRY KATZMAN, M.D., INC., APC
Ophthalmology
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 697-4600
QUANG NGUYEN O.D.
Optometrist
6945 EL CAJON BLVD
SAN DIEGO, CA 92115
San Diego County (619) 697-4600

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 Ai (theresa) Nguyen's NPI number?

The NPI number for Ai (theresa) Nguyen is 1508857533. It was assigned to this individual provider in the NPPES registry on October 31, 2005.

Where is Ai (theresa) Nguyen located?

Ai (theresa) Nguyen practices at 6945 El Cajon Blvd, San Diego, CA 92115. The listed phone number is (619) 697-4600.

What is Ai (theresa) Nguyen's specialty?

The primary specialty registered for this NPI is Optometrist with taxonomy code 152W00000X.

Is Ai (theresa) Nguyen enrolled in Medicare?

Yes. Ai (theresa) Nguyen 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.

What insurance does Ai (theresa) Nguyen accept?

Health plans from Blue Cross and Blue Shield of Louisiana and Providence Health Plan list Ai (theresa) Nguyen as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Ai (theresa) Nguyen was last updated on February 28, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.