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Try CasePilotCPT 93970 is defined as: “Duplex scan of extremity veins including responses to compression and other maneuvers; complete bilateral study.” The official Medicare billing and coding article for Peripheral Venous Ultrasound (A52993), linked to LCD L35451, reiterates that 93970 represents a complete duplex evaluation of veins in both extremities of the same anatomic region (both upper or both lower).
A duplex study requires integration of:
CMS LCD materials and reconsideration documentation for L35451 emphasize that omission of required elements or venous segments downgrades the exam to a limited study.
93970 is most commonly performed for:
For lower extremity studies, typical venous segments include:
For upper extremities:
The study must document compressibility and Doppler flow characteristics in each required segment. ACR vascular ultrasound exam requirements reinforce the need for comprehensive documentation of flow direction and Doppler analysis in venous examinations.
If the documentation does not support a complete bilateral evaluation, 93970 is not appropriate.
Medicare policy clearly distinguishes:
CMS Article A52993 explicitly states that 93971 is used when the study is unilateral or otherwise limited, and 93970 should not be used when criteria for complete bilateral evaluation are not met.
| Feature | 93970 | 93971 |
|---|---|---|
| Laterality | Both extremities (same region) | One extremity OR limited bilateral |
| Scope | Complete required venous segments | Incomplete or unilateral |
| Modifier -50 | Not applicable (inherently bilateral) | Not used; already accounts for unilateral or limited bilateral |
| Mutual Exclusivity | Do not report with 93971 for same region | Do not report with 93970 for same region |
MedLearn Radiology guidance clarifies that if all four extremities are studied (upper and lower), separate codes may be appropriate, often requiring modifier 59 on the second study to indicate a distinct anatomic region.
However, 93970 and 93971 should not be reported together for the same lower or upper extremity encounter.
Medicare coverage is governed by LCD L35451 and its associated billing article A52993. Coverage is contingent upon documentation of medical necessity.
Common ICD-10 categories that support 93970 include:
The CMS billing article provides specific ICD-10 codes recognized for coverage determination. Use of nonspecific diagnosis codes without clinical justification may result in denial.
Medical necessity must show:
Routine screening without signs or symptoms is generally not covered.
LCD L35451 and Article A52993 establish that:
Commercial payer edit rules (e.g., EmblemHealth) specify that venous duplex codes 93970–93971 are not payable with arterial duplex codes (93922–93931) unless separate medical necessity exists.
In practice:
According to the Medicare Claims Processing Manual, Chapter 13 (Radiology Services), diagnostic ultrasound services may be billed globally or split using modifiers 26 and TC.
Both components must be fully supported by documentation.
Used when only professional interpretation is billed. Requires:
Used by facilities or IDTFs billing only the technical portion.
Applied when:
MedLearn Radiology guidance illustrates appropriate use of modifier 59 when multiple extremity duplex exams are performed on different regions the same day.
Modifier misuse—particularly applying 59 to bypass bundling edits without clear anatomic distinction—is a known audit trigger.
ACR Vascular Ultrasound exam requirements emphasize:
CMS policy requires retention of images and documentation of both normal and abnormal findings.
Minimum report elements:
Failure to document compression or Doppler waveforms may result in downcoding to 93971 or claim denial.
Patient presents with bilateral lower extremity swelling. Complete duplex exam of both legs performed. All required venous segments documented. Acute thrombus found in left popliteal vein.
Coding: 93970 Diagnosis: I82.x (acute DVT) Modifiers: None (unless split billing)
Right leg evaluated only. Left leg not imaged.
Coding: 93971 Diagnosis: R22.41 (right lower limb swelling)
Patient evaluated for suspected upper extremity thrombosis and lower extremity swelling same day.
Coding: 93970 (lower extremities) + 93970-59 (upper extremities), if both complete and medically justified.
Auditors frequently compare:
Mismatch between documentation and code selection is the most common reason for recoupment.
© Copyright 2026 American Medical Association. All rights reserved.
A duplex scan of extremity veins is a specialized vascular ultrasound procedure designed to assess the condition of veins in the arms and legs. This comprehensive study employs both B-mode imaging and Doppler ultrasound techniques to provide a detailed evaluation of venous structures and blood flow dynamics. During the procedure, a clear gel is applied to the skin over the area of interest to facilitate the transmission of sound waves. A B-mode transducer is then placed on the skin, generating real-time images of the veins as the probe is moved across the targeted region. The B-mode component captures the anatomical structure of the veins, while the Doppler function measures the velocity and direction of blood flow within these vessels. The Doppler probe, integrated within the B-mode transducer, emits sound waves that reflect off moving blood cells, allowing for the assessment of blood flow patterns. Changes in the pitch of the reflected sound waves can indicate variations in blood flow, such as reduced flow or complete obstruction of a vessel. The data collected during the scan is processed by a computer, which converts the sound waves into visual images that are color-coded to represent the speed and direction of blood flow, as well as any potential blockages. Additionally, the duplex scan may include a baseline evaluation followed by further scans that utilize compression or other maneuvers to alter blood flow, providing a comprehensive assessment of venous function. After the procedure, the physician interprets the findings and documents them in a written report. For a complete bilateral study of the upper or lower extremity veins, the appropriate code to use is 93970, while a unilateral or limited study is coded as 93971.
© Copyright 2026 Coding Ahead. All rights reserved.
The duplex scan of extremity veins is indicated for various clinical scenarios where assessment of venous function and anatomy is necessary. The following conditions may warrant this procedure:
The duplex scan of extremity veins involves several key procedural steps to ensure a thorough evaluation of the venous system. The following steps outline the process:
After the duplex scan of extremity veins, there are typically no specific post-procedure care requirements, as the procedure is non-invasive and does not involve any recovery time. Patients can resume their normal activities immediately following the examination. The physician will review the results with the patient, discussing any findings and potential next steps based on the interpretation of the duplex scan. It is important for patients to follow up with their healthcare provider to address any concerns or further evaluations that may be necessary based on the results of the study.
| Short Descr | EXTREMITY STUDY | Medium Descr | DUP-SCAN XTR VEINS COMPLETE BILATERAL STUDY | Long Descr | Duplex scan of extremity veins including responses to compression and other maneuvers; complete bilateral study | Status Code | Active Code | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 1 - Diagnostic Tests for Radiology Services | Multiple Procedures (51) | 6 - Special payment adjustment rules on the technical component (TC) of multiple diagnostic cardiovascular services apply... | Bilateral Surgery (50) | 2 - 150% payment adjustment does NOT apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 0 - Payment restriction for assistants at surgery applies to this procedure... | Co-Surgeons (62) | 0 - Co-surgeons not permitted for this procedure. | Team Surgery (66) | 0 - Team surgeons not permitted for this procedure. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | APC Status Indicator | Procedure or Service, Not Discounted when Multiple | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | I3F - Echography/ultrasonography - other | MUE | 1 | CCS Clinical Classification | 197 - Other diagnostic ultrasound |
| 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | 51 | Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d). | TC | Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | GC | This service has been performed in part by a resident under the direction of a teaching physician | GZ | Item or service expected to be denied as not reasonable and necessary | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | GW | Service not related to the hospice patient's terminal condition | GA | Waiver of liability statement issued as required by payer policy, individual case | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | 76 | Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | CR | Catastrophe/disaster related | X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | RT | Right side (used to identify procedures performed on the right side of the body) | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | 52 | Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use). | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner | LT | Left side (used to identify procedures performed on the left side of the body) | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | Q5 | Service furnished under a reciprocal billing arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | U6 | Medicaid level of care 6, as defined by each state | 27 | Multiple outpatient hospital e/m encounters on the same date: for hospital outpatient reporting purposes, utilization of hospital resources related to separate and distinct e/m encounters performed in multiple outpatient hospital settings on the same date may be reported by adding modifier 27 to each appropriate level outpatient and/or emergency department e/m code(s). this modifier provides a means of reporting circumstances involving evaluation and management services provided by physician(s) in more than one (multiple) outpatient hospital setting(s) (eg, hospital emergency department, clinic). note: this modifier is not to be used for physician reporting of multiple e/m services performed by the same physician on the same date. for physician reporting of all outpatient evaluation and management services provided by the same physician on the same date and performed in multiple outpatient setting(s) (eg, hospital emergency department, clinic), see evaluation and management, emergency department, or preventive medicine services codes. | 50 | Bilateral procedure: unless otherwise identified in the listings, bilateral procedures that are performed at the same session, should be identified by adding modifier 50 to the appropriate 5 digit code. note: this modifier should not be appended to designated "add-on" codes (see appendix d). | 53 | Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use). | 56 | Preoperative management only: when 1 physician or other qualified health care professional performed the preoperative care and evaluation and another performed the surgical procedure, the preoperative component may be identified by adding modifier 56 to the usual procedure number. | 58 | Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78. | 78 | Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.) | 79 | Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.) | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | A6 | Dressing for six wounds | AG | Primary physician | AM | Physician, team member service | BA | Item furnished in conjunction with parenteral enteral nutrition (pen) services | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GQ | Via asynchronous telecommunications system | GT | Via interactive audio and video telecommunication systems | GX | Notice of liability issued, voluntary under payer policy | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | JC | Skin substitute used as a graft | KX | Requirements specified in the medical policy have been met | MA | Ordering professional is not required to consult a clinical decision support mechanism due to service being rendered to a patient with a suspected or confirmed emergency medical condition | MC | Ordering professional is not required to consult a clinical decision support mechanism due to the significant hardship exception of electronic health record or clinical decision support mechanism vendor issues | ME | The order for this service adheres to appropriate use criteria in the clinical decision support mechanism consulted by the ordering professional | MG | The order for this service does not have applicable appropriate use criteria in the qualified clinical decision support mechanism consulted by the ordering professional | MH | Unknown if ordering professional consulted a clinical decision support mechanism for this service, related information was not provided to the furnishing professional or provider | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | Q3 | Live kidney donor surgery and related services | QJ | Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b) | SA | Nurse practitioner rendering service in collaboration with a physician | T5 | Right foot, great toe | TE | Lpn/lvn | U2 | Medicaid level of care 2, as defined by each state | U7 | Medicaid level of care 7, as defined by each state | X1 | Continuous/broad services: for reporting services by clinicians, who provide the principal care for a patient, with no planned endpoint of the relationship; services in this category represent comprehensive care, dealing with the entire scope of patient problems, either directly or in a care coordination role; reporting clinician service examples include, but are not limited to: primary care, and clinicians providing comprehensive care to patients in addition to specialty care |
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| 1992-01-01 | Added | First appearance in code book in 1992. |
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