Physician Profile
Unclaimed ProfileAbout DUFFY
Mark T Duffy, MD practises ophthalmology in Green Bay, WI. Mark is a 1992 graduate of University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb).
Summarised automatically from public NPI registry and CMS Medicare data. Not written or reviewed by this provider. Claim this profile to replace it.
Education & Training
Areas of Expertise
Common questions
What does Dr. Duffy specialise in?
Dr. Duffy is an ophthalmology in Green Bay, WI. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “OPHTHALMOLOGY”.
NPI registry
Where is Dr. Duffy located?
Dr. Duffy is listed at 2253 W MASON ST, Green Bay, WI 54303. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Duffy's phone number?
The number on file is (920) 327-7000. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is the NPI for Dr. Duffy?
Dr. Duffy's National Provider Identifier is 1235167537. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Duffy go to medical school?
Dr. Duffy attended University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb), graduating in 1992. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Dr. Duffy have?
Dr. Duffy has 34 years experience. Calculated from a graduation year of 1992, reported in the CMS National Downloadable File.
CMS public data
What does Dr. Duffy do most often?
According to Medicare billing data, Dr. Duffy performs procedures including removal of excessive skin and fat of upper eyelid, injection of chemical for paralysis of nerve muscles on side of face and dilation of tear drainage opening; provides treatments such as exam of visual field with limited testing, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Dr. Duffy's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Duffy. If this is you, claiming it is free.
Guide.md
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (920) 327-7000
- Email not available
Practice Locations
2253 W MASON ST
Green Bay, WI 54303
Procedures Most Often Billed to Medicare
7,281 services · 763 patients · 14 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Removal of excessive skin and fat of upper eyelid | Procedure | 15823 |
79 |
| Injection of chemical for paralysis of nerve muscles on side of face | Procedure | 64612 |
56 |
| Dilation of tear drainage opening | Procedure | 68801 |
27 |
| Repair of brow paralysis | Procedure | 67900 |
27 |
| Extensive repair of turning-outward eyelid defect | Procedure | 67917 |
20 |
| Repair of tendon of upper eyelid | Procedure | 67904 |
19 |
| Extensive repair of turning-inward eyelid defect | Procedure | 67924 |
11 |
| Shortening or advancement of upper eyelid muscle to correct drooping or paralysis | Procedure | 67903 |
11 |
| Exam of visual field with limited testing | Treatment | 92081 |
192 |
| Injection, onabotulinumtoxina, 1 unit | Drug given | J0585 |
6,497 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
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Claim this profileRelated providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other ophthalmology specialists at this location 6
Same specialty, same street address — most likely the same department or group.
Also at this address 4
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
Other ophthalmology specialists in Green Bay 6
Same specialty, same city.
More connections — 23 related providers in 3 groups
Trained at University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb) 8
Other providers in the same specialty who trained at the same institution.
Class of 1992 at University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb) 7
Providers who graduated from the same medical school in the same year.
Also performs Removal of excessive skin and fat of upper eyelid 8
Providers in WI who bill this service to Medicare most often.
Provider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.