Physician Profile
Unclaimed ProfileAbout WALKER
Based in San Antonio, TX, John Allen Walker, M.D. is listed in the NPI registry under diagnostic radiology. John graduated from University of Texas Medical School at San Antonio in 2007. John is also listed as specialising in vascular & interventional radiology.
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 is Dr. Walker's specialty?
Dr. Walker is a diagnostic radiology in San Antonio, TX. This is the primary taxonomy recorded against the NPI in the federal registry, listed there as “DIAGNOSTIC RADIOLOGY”.
NPI registry
Where can I find Dr. Walker?
Dr. Walker is listed at 4502 MEDICAL DR, San Antonio, TX 78229. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How do I contact Dr. Walker?
The number on file is (210) 358-4000. Guide.md cannot book appointments or pass on messages — please call the office directly.
NPI registry
What is Dr. Walker's NPI number?
Dr. Walker's National Provider Identifier is 1477780344. 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
What is Dr. Walker's medical education?
Dr. Walker attended University of Texas Medical School at San Antonio, graduating in 2007. This comes from the CMS National Downloadable File.
CMS public data
How long has Dr. Walker been practising?
Dr. Walker has 19 years experience. Calculated from a graduation year of 2007, reported in the CMS National Downloadable File.
CMS public data
What is Dr. Walker known for?
According to Medicare billing data, Dr. Walker performs procedures including needle biopsy of kidney, insertion of central venous tube with port and fine needle aspiration biopsy using ultrasound guidance, first growth; reads or performs imaging such as ultrasonic guidance for blood vessel access and review by radiologist of additional artery image; provides treatments such as use of a drug to induce depression of consciousness by physician performing a procedure , initial 15 minutes, alongside routine visits and testing. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Has Dr. Walker confirmed this information?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Walker. If this is you, claiming it is free.
Guide.md
Licensing & Certification
Source: NPPES NPI Registry
Contact Information
- (210) 358-4000
- Email not available
Practice Locations
4502 MEDICAL DR
San Antonio, TX 78229
Procedures Most Often Billed to Medicare
366 services · 308 patients · 13 distinct codes
| Procedure | Type | Code | Services |
|---|---|---|---|
| Needle biopsy of kidney | Procedure | 50200 |
18 |
| Insertion of central venous tube with port (5 years or older) | Procedure | 36561 |
13 |
| Fine needle aspiration biopsy using ultrasound guidance, first growth | Procedure | 10005 |
11 |
| Ultrasonic guidance for blood vessel access | Imaging | 76937 |
39 |
| Review by radiologist of additional artery image | Imaging | 75774 |
39 |
| Ultrasonic guidance for needle placement | Imaging | 76942 |
32 |
| Fluoroscopic guidance for insertion or removal of central vein access device | Imaging | 77001 |
25 |
| X-ray of chest, 1 view | Imaging | 71045 |
20 |
| Review by radiologist of ct guidance for needle placement | Imaging | 77012 |
15 |
| Ct scan of blood vessels of abdomen and pelvis with contrast | Imaging | 74174 |
11 |
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 diagnostic radiology specialists at this location 1
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 diagnostic radiology specialists in San Antonio 7
Same specialty, same city.
More connections — 23 related providers in 3 groups
Trained at University of Texas Medical School at San Antonio 8
Other providers in the same specialty who trained at the same institution.
Class of 2007 at University of Texas Medical School at San Antonio 7
Providers who graduated from the same medical school in the same year.
Also performs Needle biopsy of kidney 8
Providers in TX 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.