Physician Profile
Mark Brennan, DO
Unclaimed ProfileAbout Dr. Brennan
Based in Johnson City, NY, Mark Brennan, DO is listed in the NPI registry under vascular surgery. Mark graduated from Philadelphia College of Osteopathic Medicine in 1994. Mark is also listed as specializing in surgery. Medicare claims data shows Mark provided 143 services to 129 patients.
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
Specialty
Credentials & Licensing
Source: NPPES NPI Registry
Contact Information
- (607) 763-8100
- Email not available
Practice Locations
30 HARRISON ST STE 455
Johnson City, NY 13790
Conditions Commonly Evaluated or Treated
Within Vascular Surgery generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Most searched conditions
Procedures & services
Most searched procedures
Procedures Most Often Billed to Medicare
143 services · 129 patients · 7 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Insertion of needle and/or tube into hemodialysis circuit and balloon dilation of dialysis segment with review by radiologist | Procedure | 36902 |
19 |
| Insertion of tunneled central venous tube for infusion (5 years or older) | Procedure | 36558 |
18 |
| Ultrasonic guidance for blood vessel access | Imaging | 76937 |
37 |
| Fluoroscopic guidance for insertion or removal of central vein access device | Imaging | 77001 |
20 |
| Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more | Office visit | 99213 |
20 |
| Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Office visit | 99232 |
15 |
| New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more | Office visit | 99203 |
14 |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other vascular surgeons at this location 1
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 6
Clinically related specialties at the same address — the people this provider most likely works alongside.
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.
More connections — 24 related providers in 3 groups
Trained at Philadelphia College of Osteopathic Medicine 8
Other providers in the same specialty who trained at the same institution.
Class of 1994 at Philadelphia College of Osteopathic Medicine 8
Providers who graduated from the same medical school in the same year.
Also performs Insertion of needle and/or tube into hemodialysis circuit and balloon dilation of dialysis segment with review by radiologist 8
Providers in NY who bill this service to Medicare most often.
Common questions
What does Dr. Brennan specialize in?
Dr. Brennan is a vascular surgeon in Johnson City, NY. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “VASCULAR SURGERY”.
NPI registry
Where is Dr. Brennan located?
Dr. Brennan is listed at 30 HARRISON ST STE 455, Johnson City, NY 13790. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
What is Dr. Brennan's phone number?
The number on file is (607) 763-8100. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is the NPI for Dr. Brennan?
Dr. Brennan's National Provider Identifier is 1174523443. 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. Brennan go to medical school?
Dr. Brennan attended Philadelphia College of Osteopathic Medicine, graduating in 1994. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Dr. Brennan have?
Dr. Brennan has 32 years experience. Calculated from a graduation year of 1994, reported in the CMS National Downloadable File.
CMS public data
What does Dr. Brennan do most often?
According to Medicare billing data, Dr. Brennan performs procedures including insertion of needle and/or tube into hemodialysis circuit and balloon dilation of dialysis segment with review by radiologist and insertion of tunneled central venous tube for infusion; reads or performs imaging such as ultrasonic guidance for blood vessel access and fluoroscopic guidance for insertion or removal of central vein access device, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Dr. Brennan's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Brennan. If this is you, claiming it is free.
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Claim this profileProvider data sourced from the NPPES NPI Registry and CMS public datasets. Information is provided for reference and is not medical advice.