Quick answers
- Does Federico A A. Maestre Grau accept Medicare assignment?
- Yes. Medicare's clinician data says Federico A A. Maestre Grau 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 Federico A A. Maestre Grau see?
- In 2024, CMS data shows 255 Original Medicare patients and 594 services for Federico A A. Maestre Grau. This counts Original Medicare only and measures volume, not quality.
- What is Federico A A. Maestre Grau's NPI number?
- 1679561047. 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 Federico A A. Maestre Grau, 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 | 255 |
|---|---|
| Services billed to Medicare | 594 |
| Different services or procedures | 18 |
| Participating Medicare provider | Yes |
| Average age of these patients | 78 |
Most frequent services
- Established patient problem focused exam of visual system (92012)422 services
- New patient complete exam of visual system (92004)58 services
- Imaging of optic nerve (92133)44 services
- Imaging of retina (92134)32 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 blood pressure75%
- High cholesterol75%
- Diabetes62%
- Arthritis45%
- Chronic kidney disease25%
- Ischemic heart disease24%
Practice locations
Addresses where Federico A A. Maestre Grau is enrolled with Medicare (CMS data updated October 2, 2026).
- 357 Ave De La ConstitucionSan Juan, PR 00901 (787) 289‑6600
Group practices
Medicare enrollment lists Federico A A. Maestre Grau as a member of this group (CMS data updated October 2, 2026).
- Eye Care of San Juan P S C2 clinicians in the group
Specialties
- Ophthalmologyprimary
Other ophthalmologists in San Juan
Clinicians with the same Medicare primary specialty in San Juan, PR — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Ponce School Of Medicine |
| Graduation year | 1986 (40 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1679561047 |
| 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