Quick answers
- Does Andrew W. Nahas accept Medicare assignment?
- Yes. Medicare's clinician data says Andrew W. Nahas 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 Andrew W. Nahas see?
- In 2024, CMS data shows 616 Original Medicare patients and 5,199 services for Andrew W. Nahas. This counts Original Medicare only and measures volume, not quality.
- What is Andrew W. Nahas's NPI number?
- 1427052927. 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 Andrew W. Nahas, 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 | 616 |
|---|---|
| Services billed to Medicare | 5,199 |
| Different services or procedures | 19 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Removal of cataract with insertion of prosthetic lens (66984)3,690 services
- Established patient complete exam of visual system (92014)503 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)175 services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)147 services
- Imaging of retina (92134)83 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 pressure63%
- High cholesterol59%
- Arthritis33%
- Diabetes29%
- Chronic kidney disease27%
- Ischemic heart disease18%
Practice locations
Addresses where Andrew W. Nahas is enrolled with Medicare (CMS data updated October 2, 2026).
- 120 2nd Ave SEWaukon, IA 52172 (563) 568‑3000
- 407 S Main StViroqua, WI 54665 (608) 637‑3195
- 50 N 4th StLansing, IA 52151 (563) 538‑4874
Group practices
Medicare enrollment lists Andrew W. Nahas as a member of this group (CMS data updated October 2, 2026).
- Gundersen Clinic Ltd418 clinicians in the group
Specialties
- Optometryprimary
Other optometrists in Iowa
Clinicians with the same Medicare primary specialty in Iowa — not a recommendation.
Other clinicians in Gundersen Clinic Ltd
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | OD |
|---|---|
| Optometry school | Pennsylvania College Of Optometry |
| Graduation year | 1994 (32 years since optometry school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1427052927 |
| 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