Dr. Louis Chang, M.D., PH.D.
What this data tells you about Dr. Chang
Dr. Louis Chang is an ophthalmology specialist in Los Angeles, CA, with 19 years of NPI registration. Based on federal Medicare data, Dr. Chang performed 14,804 Medicare services across 2,159 unique beneficiaries.
Between the years covered by Open Payments, Dr. Chang received a total of $40,980 from 11 pharmaceutical and/or device companies across 56 individual payments. These payments are legal, publicly disclosed under the federal Sunshine Act, and common in ophthalmology. The majority of payments are for speaking programs and promotional activities, reflecting participation in industry-sponsored events. Patients may wish to discuss these relationships with their provider.
The Data Coverage level for Dr. Chang is Very High — reflecting how much public federal data is available about this provider. Patients are encouraged to use this data as one of several factors when choosing a healthcare provider.
Medicare Practice Summary
Medicare Utilization ↗Top procedures by volume
Ranked by number of services performed for Medicare patients. Avg. submitted charge is what the provider billed; avg. Medicare payment is what CMS paid.
| Procedure | Volume | Avg. paid | Avg. submitted |
|---|---|---|---|
| Eye injection (Vabysmo/faricimab) An injection of faricimab-svoa, a medication administered in 0.1 mg doses. |
6,240 | $28 | $78 |
| Aflibercept eye injection (Eylea) | 2,075 | $691 | $1,719 |
| Retinal imaging (OCT scan) This procedure involves imaging the retina to visualize its structure. It is used to examine the back of the eye. |
2,038 | $39 | $100 |
| Eye injection for retinal disease A procedure involving the administration of medication directly into the eye. |
1,293 | $111 | $725 |
| Injection, ranibizumab, 0.1 mg | 1,235 | $180 | $675 |
| Eye exam, established patient, focused A limited examination of the visual system for an existing patient. The provider focuses on a specific eye-related concern or symptom. |
1,026 | $84 | $230 |
| Comprehensive eye exam, established patient A comprehensive examination of the visual system performed for a patient who has previously been seen by the provider. |
225 | $110 | $300 |
| Comprehensive eye exam, new patient A comprehensive examination of the visual system performed for a new patient. |
113 | $134 | $400 |
| Office visit, established patient (20-29 min) An office visit for an existing patient lasting between 20 and 29 minutes. The visit involves medical evaluation and management of the patient's condition. |
110 | $87 | $230 |
| Retinal angiography with dye injection This procedure uses a special camera to examine the blood vessels in the retina after a dye has been injected into the body. |
89 | $136 | $245 |
| Retinal photography (fundus photo) This procedure involves taking photographs of the retina, the light-sensitive tissue at the back of the eye. It is used to document the condition of the eye's interior structures. |
86 | $34 | $130 |
| Compounded drug, not otherwise classified A medication prepared specifically for an individual patient by a pharmacist or physician, tailored to meet unique needs that cannot be fulfilled by commercially available products. |
75 | $73 | $96 |
| Office visit, established patient (10-19 min) An office visit for an existing patient lasting 10 to 19 minutes. The visit involves medical evaluation and management of the patient's condition. |
72 | $56 | $85 |
| Office visit, established patient (30-39 min) A follow-up office visit for an existing patient lasting between 30 and 39 minutes. The visit involves medical evaluation and management of the patient's condition. |
48 | $104 | $300 |
| New patient office visit (45-59 min) An initial office visit for a new patient lasting between 45 and 59 minutes. This code covers the total time spent by the physician or qualified healthcare professional on the date of the encounter. |
41 | $152 | $400 |
| Ultrasound of eye tissue and structures A diagnostic imaging test that uses sound waves to create pictures of the eye's internal tissues and structures. |
27 | $47 | $220 |
| Extended eye exam with retinal drawing A detailed examination of the back of the eye that includes creating a drawing of the retina. |
11 | $24 | $100 |
Industry Payment Transparency
Open Payments through 2024 ↗Payment profile
Industry payments classified by relationship type. Not all payments are equal — research and consulting reflect different relationships than speaking programs or meals.
Payment trend by year
Annual totals from pharmaceutical and medical device companies.
Payments by company (2024)
All-time payments by company (2018-2024) ›
Associated products mentioned in payments ›
The majority of payments (57%) are for speaking programs and promotional activities, which reflect participation in industry-sponsored educational or marketing events. This is common in ophthalmology and does not inherently indicate bias, but patients may wish to be aware. Total industry engagement is in the top 8% for ophthalmology in CA.
Geographic Context
0.0 mi
Data Sources
| Provider Registry | ✓ NPPES | Weekly updates |
| Medicare Enrollment | ✓ PECOS | Monthly updates |
| Practice Data | ✓ Medicare Util. | Annual (CY lag) |
| Industry Payments | ✓ Open Payments | CY 2024 |
| Disciplinary History | — Not public | N/A |
This provider has data in 4 of 4 available federal datasets, with a Data Coverage level of Very High. This reflects how much public data is available about a provider. How we calculate this →
Summary
Dr. Chang is a mixed practice specialist, with above-average Medicare volume (top 7% in CA), with speaking/promotional industry engagement in the top 8% of CA peers, with 19 years of NPI registration.
This summary is auto-generated from federal data, describing data availability and patterns. Read our methodology →
Frequently Asked Questions
Is Dr. Chang experienced with eye injection (vabysmo/faricimab)?
Does Dr. Chang receive payments from pharmaceutical companies?
How do Dr. Chang's costs compare to other ophthalmologists in Los Angeles?
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All data on this page is sourced verbatim from public federal records published by the U.S. Centers for Medicare & Medicaid Services (CMS): NPPES ↗, Open Payments ↗, Medicare Provider Utilization ↗, and PECOS. Publication is mandated by the Physician Payments Sunshine Act (§6002 ACA, 42 U.S.C. §1320a-7h) and the Freedom of Information Act.
This page is not medical advice, an endorsement, a recommendation, or a quality rating. Data Coverage reflects data completeness — how much federal information exists for this provider — not clinical performance, patient outcomes, or quality of care. Always verify information directly with the provider and consult a licensed clinician before making medical decisions.
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