Total Payments
$362,953
2024 Payments
$60,682
Companies
44
Transactions
471
Medicare Patients
3,564
Medicare Billing
$475,178
Payment Breakdown by Category
Other$174,170 (48.0%)
Travel$104,325 (28.7%)
Consulting$59,900 (16.5%)
Food & Beverage$16,333 (4.5%)
Research$4,125 (1.1%)
Education$4,100 (1.1%)
Payments by Nature
| Nature of Payment | Amount | Transactions | Share |
|---|---|---|---|
| Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program | $115,900 | 38 | 31.9% |
| Travel and Lodging | $104,325 | 105 | 28.7% |
| Consulting Fee | $59,900 | 20 | 16.5% |
| Honoraria | $47,770 | 18 | 13.2% |
| Food and Beverage | $16,333 | 281 | 4.5% |
| Compensation for serving as faculty or as a speaker for a non-accredited and noncertified continuing education program | $10,500 | 3 | 2.9% |
| Unspecified | $4,125 | 2 | 1.1% |
| Education | $4,100 | 4 | 1.1% |
Payments by Type
General
$358,828
469 transactions
Research
$4,125
2 transactions
Top Paying Companies
| Company | Total | Records | Latest Year |
|---|---|---|---|
| Penumbra, Inc. | $139,942 | 119 | $0 (2024) |
| Philips Electronics North America Corporation | $116,204 | 78 | $0 (2023) |
| Cook Incorporated | $53,408 | 68 | $0 (2018) |
| W. L. Gore & Associates, Inc. | $17,137 | 43 | $0 (2024) |
| Contego Medical, Inc | $12,281 | 6 | $0 (2024) |
| Medtronic, Inc. | $8,319 | 13 | $0 (2024) |
| Medtronic Vascular, Inc. | $6,745 | 49 | $0 (2020) |
| Boston Scientific Corporation | $4,258 | 12 | $0 (2024) |
| Cook Medical LLC | $1,503 | 12 | $0 (2023) |
| Inari Medical, Inc. | $735.92 | 4 | $0 (2022) |
Payment History by Year
| Year | Amount | Transactions | Top Company |
|---|---|---|---|
| 2024 | $60,682 | 51 | Penumbra, Inc. ($50,362) |
| 2023 | $73,941 | 54 | Penumbra, Inc. ($60,584) |
| 2022 | $26,814 | 43 | Penumbra, Inc. ($10,045) |
| 2021 | $16,785 | 31 | Penumbra, Inc. ($11,241) |
| 2020 | $22,621 | 29 | W. L. Gore & Associates, Inc. ($13,018) |
| 2019 | $24,628 | 60 | Philips Electronics North America Corporation ($15,898) |
| 2018 | $69,370 | 82 | Philips Electronics North America Corporation ($44,150) |
| 2017 | $68,112 | 121 | Cook Incorporated ($35,837) |
All Payment Transactions
471 individual payment records from CMS Open Payments — Page 1 of 19
| Date | Company | Product | Nature | Form | Amount | Type |
|---|---|---|---|---|---|---|
| 12/19/2024 | Edwards Lifesciences Corporation | CARPENTIER-EDWARDS PHYSIO II ANNULOPLASTY RING (Device) | Food and Beverage | In-kind items and services | $36.76 | General |
| Category: Heart Valve Repair | ||||||
| 12/13/2024 | Penumbra, Inc. | Indigo System (Device) | Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program | Cash or cash equivalent | $4,800.00 | General |
| Category: Peripheral Intervention | ||||||
| 12/13/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $42.00 | General |
| Category: Peripheral Intervention | ||||||
| 12/10/2024 | Penumbra, Inc. | Indigo System (Device) | Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program | Cash or cash equivalent | $3,200.00 | General |
| Category: Peripheral Intervention | ||||||
| 12/10/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $21.00 | General |
| Category: Peripheral Intervention | ||||||
| 12/08/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $188.23 | General |
| Category: Peripheral Intervention | ||||||
| 12/06/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $922.70 | General |
| Category: Peripheral Intervention | ||||||
| 12/06/2024 | Penumbra, Inc. | Indigo System (Device) | Food and Beverage | Cash or cash equivalent | $626.64 | General |
| Category: Peripheral Intervention | ||||||
| 12/06/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $502.95 | General |
| Category: Peripheral Intervention | ||||||
| 12/06/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $188.23 | General |
| Category: Peripheral Intervention | ||||||
| 12/06/2024 | Penumbra, Inc. | Indigo System (Device) | Food and Beverage | Cash or cash equivalent | $128.00 | General |
| Category: Peripheral Intervention | ||||||
| 11/26/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $321.98 | General |
| Category: Peripheral Intervention | ||||||
| 11/26/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $230.65 | General |
| Category: Peripheral Intervention | ||||||
| 11/25/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $417.98 | General |
| Category: Peripheral Intervention | ||||||
| 11/25/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $233.65 | General |
| Category: Peripheral Intervention | ||||||
| 11/25/2024 | Penumbra, Inc. | Indigo System (Device) | Food and Beverage | Cash or cash equivalent | $153.19 | General |
| Category: Peripheral Intervention | ||||||
| 11/21/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $222.08 | General |
| Category: Peripheral Intervention | ||||||
| 11/21/2024 | Smith+Nephew, Inc. | ACTICOAT 4" X 4" (Device), PICO | Food and Beverage | In-kind items and services | $26.60 | General |
| Category: Infection Management | ||||||
| 10/23/2024 | Abbott Laboratories | AMPLATZER AMULET (Device) | Food and Beverage | In-kind items and services | $28.18 | General |
| Category: Structural Heart | ||||||
| 10/11/2024 | Penumbra, Inc. | Penumbra System (Device) | Food and Beverage | Cash or cash equivalent | $24.75 | General |
| Category: Neurointervention | ||||||
| 10/10/2024 | Penumbra, Inc. | Indigo System (Device) | Food and Beverage | Cash or cash equivalent | $115.61 | General |
| Category: Peripheral Intervention | ||||||
| 10/10/2024 | W. L. Gore & Associates, Inc. | EXCLUDER Conformable AAA Endoprosthesis with Active Control (Device) | Food and Beverage | In-kind items and services | $91.83 | General |
| Category: Devices | ||||||
| 09/30/2024 | Penumbra, Inc. | Indigo System (Device) | Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program | Cash or cash equivalent | $3,600.00 | General |
| Category: Peripheral Intervention | ||||||
| 09/30/2024 | Penumbra, Inc. | Indigo System (Device) | Travel and Lodging | Cash or cash equivalent | $63.00 | General |
| Category: Peripheral Intervention | ||||||
| 09/26/2024 | Boston Scientific Corporation | Ranger (Device) | Food and Beverage | In-kind items and services | $24.19 | General |
| Category: Ranger_PI | ||||||
Research Studies & Clinical Trials
| Study Name | Company | Amount | Records |
|---|---|---|---|
| PERFORMANCE II | Contego Medical, Inc | $2,250 | 1 |
| Performance II | Contego Medical, Inc | $1,875 | 1 |
Medicare Billing by Year
| Year | Procedures | Beneficiaries | Services | Submitted | Medicare Paid |
|---|---|---|---|---|---|
| 2023 | 24 | 1,284 | 1,550 | $922,043 | $121,962 |
| 2022 | 20 | 766 | 988 | $483,498 | $101,748 |
| 2021 | 19 | 790 | 1,009 | $744,281 | $121,145 |
| 2020 | 20 | 724 | 956 | $968,360 | $130,323 |
Total Patients
3,564
Total Services
4,503
Medicare Billing
$475,178
Procedure Codes
89
All Medicare Procedures & Services
89 procedure records from CMS Medicare Utilization — Page 1 of 4
| HCPCS | Description | Setting | Year | Patients | Services | Charges | Medicare Paid | Ratio |
|---|---|---|---|---|---|---|---|---|
| 99214 | Established patient office or other outpatient visit, 30-39 minutes | Office | 2023 | 220 | 307 | $85,432 | $27,731 | 32.5% |
| 93880 | Ultrasound of both sides of head and neck blood flow | Office | 2023 | 77 | 83 | $46,262 | $10,328 | 22.3% |
| 93970 | Ultrasound study of arm or leg veins with compression and maneuvers | Office | 2023 | 66 | 68 | $48,178 | $8,876 | 18.4% |
| 93922 | Ultrasound study of arm and leg arteries | Office | 2023 | 107 | 152 | $47,928 | $7,392 | 15.4% |
| 93971 | Ultrasound study of one arm or leg veins with compression and maneuvers | Office | 2023 | 67 | 80 | $34,756 | $6,855 | 19.7% |
| 93925 | Ultrasound of leg arteries or artery grafts | Office | 2023 | 30 | 38 | $35,888 | $6,101 | 17.0% |
| 37228 | Balloon dilation of artery of leg, initial vessel | Facility | 2023 | 12 | 16 | $239,780 | $5,841 | 2.4% |
| 99204 | New patient office or other outpatient visit, 45-59 minutes | Office | 2023 | 53 | 53 | $25,552 | $5,792 | 22.7% |
| 99203 | New patient office or other outpatient visit, 30-44 minutes | Office | 2023 | 74 | 74 | $23,742 | $5,703 | 24.0% |
| 36471 | Injection of chemical agent into multiple incompetent veins of leg | Office | 2023 | 13 | 36 | $23,724 | $5,058 | 21.3% |
| 93979 | Ultrasound of aorta, vena cava, groin vessels or bypass grafts | Office | 2023 | 58 | 66 | $28,749 | $4,785 | 16.6% |
| 37224 | Balloon dilation of artery of leg | Facility | 2023 | 14 | 15 | $158,112 | $3,908 | 2.5% |
| 93926 | Ultrasound of one leg arteries or artery grafts | Office | 2023 | 29 | 36 | $18,342 | $3,404 | 18.6% |
| 99213 | Established patient office or other outpatient visit, 20-29 minutes | Office | 2023 | 37 | 40 | $7,840 | $2,686 | 34.3% |
| 93976 | Ultrasound of abdomen and pelvis artery and vein blood flow | Office | 2023 | 16 | 24 | $13,446 | $2,432 | 18.1% |
| 99223 | Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes | Facility | 2023 | 18 | 18 | $10,517 | $2,241 | 21.3% |
| 99222 | Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes | Facility | 2023 | 21 | 21 | $9,868 | $2,025 | 20.5% |
| 93970 | Ultrasound study of arm or leg veins with compression and maneuvers | Facility | 2023 | 73 | 76 | $9,318 | $1,831 | 19.7% |
| 75710 | Review by radiologist of arm or leg artery image | Facility | 2023 | 21 | 25 | $6,577 | $1,492 | 22.7% |
| 76942 | Ultrasonic guidance for needle placement | Office | 2023 | 13 | 33 | $13,218 | $1,392 | 10.5% |
| 75625 | Review by radiologist of abdominal aorta image | Facility | 2023 | 25 | 28 | $6,024 | $1,367 | 22.7% |
| 93971 | Ultrasound study of one arm or leg veins with compression and maneuvers | Facility | 2023 | 53 | 55 | $4,432 | $825.69 | 18.6% |
| 93880 | Ultrasound of both sides of head and neck blood flow | Facility | 2023 | 31 | 31 | $4,399 | $813.12 | 18.5% |
| 99232 | Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes | Facility | 2023 | 14 | 16 | $3,591 | $812.40 | 22.6% |
| 99441 | Telephone medical discussion with physician, 5-10 minutes | Office | 2023 | 20 | 21 | $2,565 | $643.75 | 25.1% |
About Dr. Martyn Knowles, MD
Dr. Martyn Knowles, MD is a Surgery healthcare provider based in Raleigh, North Carolina. This provider has been registered with the National Plan and Provider Enumeration System (NPPES) since 07/23/2007. The National Provider Identifier (NPI) number assigned to this provider is 1265632731.
According to the Centers for Medicare & Medicaid Services (CMS) Open Payments database, Dr. Martyn Knowles, MD has received a total of $362,953 in payments from pharmaceutical and medical device companies, with $60,682 received in 2024. These payments were reported across 471 transactions from 44 companies. The most common payment nature is "Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program" ($115,900).
As a Medicare-enrolled provider, Knowles has provided services to 3,564 Medicare beneficiaries, totaling 4,503 services with total Medicare billing of $475,178. Data is available for 4 years (2020–2023), covering 89 distinct procedure/service records.
Ad
Practice Information
- Specialty Surgery
- Other Specialties Vascular Surgery
- Location Raleigh, NC
- Active Since 07/23/2007
- Last Updated 04/01/2021
- Taxonomy Code 208600000X
- Entity Type Individual
- NPI Number 1265632731
Products in Payments
- Indigo System (Device) $130,314
- Cook Medical AAA (Device) $33,504
- PV.035 (Device) $33,080
- IVUS Systems (Device) $26,353
- COOK MEDICAL AAA (Device) $17,076
- IGT Undivided (Device) $13,046
- (7881) US Und (Device) $11,561
- EXCLUDER Iliac Branch Endoprosthesis (Device) $10,362
- IGT D Peripheral (Device) $9,692
- ABRE (Device) $7,409
- Penumbra Ruby Coil (Device) $6,283
- US Und (Device) $6,000
- IN.PACT Admiral (Device) $5,824
- Neuroguard IEP (Device) $4,281
- Spectranetics Undiv (Device) $4,200
- General - Therapies (Device) $4,000
- (1399) MRI Equip Undiv (Device) $3,600
- TAG Thoracic Endoprosthesis (Device) $3,441
- Excipio SV (Device) $2,625
- Penumbra System (Device) $2,065
Data Sources
Provider data from NPPES. Payment data from CMS Open Payments. Medicare data from CMS Medicare Provider Utilization. All data is public and updated periodically.
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