CLINICAL PRIVILEGE WHITE PAPER

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1 Vascular Procedure ultrasound 57 Procedure 57 CLINICAL PRIVILEGE WHITE PAPER Vascular ultrasound Background Vascular ultrasound is a noninvasive procedure used to diagnose and locate disorders of the vascular system. Widespread practical application of ultrasonography began in the 1960s. Neurosonography; echocardiography; obstetrical, gynecological, and ophthalmologic ultrasound are additional examples of diagnostic ultrasound technology. Ultrasonography is an imaging technique in which structures of the body are visualized by recording the reflections or echoes of ultrasonic waves directed into the tissues. Echoes are then converted into electrical impulses and, depending on the strength of the reflections, real-time images are created and displayed on a television-like monitor in various shades of white and gray. For example, bones are highly reflective and are displayed in bright white, whereas nonreflective, fluid-filled structures are displayed in dark gray or even black. Duplex ultrasound technology specifically evaluates the blood within arteries and veins. This technology not only provides real-time images, but also predicts physiological information such as blood flow velocities from Doppler frequency shifts. Color Doppler flow imaging, the most advanced technology in vascular ultrasound, results from moving reflectors or scatterers (usually blood cells in circulation). This type of imaging incorporates the basics of duplex and also assigns a color value to blood flow depending on the direction of movement. Thus, arteries can be viewed in red and veins in blue. Vascular technology is continuing to evolve at a rapid pace, along with the similar diagnostic technologies of computer assisted x-ray tomography, or CAT scanning, and nuclear magnetic resonance imaging (MRI). Thus, it is becoming more important for physicians to either fully comprehend or become certified in vascular ultrasound techniques, because they play a greater role in interpreting vascular disease and discovering the proper course of therapy for each patient. Specifically, physicians are able to use imaging to screen patients accurately for arteriography or operations. Currently, the American Registry of Diagnostic Medical Sonographers (ARDMS) is the only organization that administers certifying examinations in vascular technology or confers the credential of registered vascular technologist (RVT). As of June 1993 there were 2,878 RVTs internationally, of which 209 (or 7%) are also MDs. More and more physicians are seeking certification in this area not only to enhance their clinical skills, but also because it is recommended by the Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL), an organization founded A supplement to Briefings on Credentialing 781/ Criteria reviewed

2 in 1987 that accredits vascular labs. ICAVL has currently accredited 398 labs, although participation in the organization is voluntary. Many physicians, who are often the directors of a vascular lab, opt to become RVTs because it is preferred by the ICAVL. The ICAVL s governing board represents all of the major societies concerned with vascular disease, and is the first organization to develop standards and study guidelines for vascular labs. These standards not only serve as a guide for clinicians seeking accreditation for their labs, but also form a basis for some uniform agreement on how vascular imaging techniques are used and interpreted. Involved specialists Positions of societies and academies ARDMS Vascular surgeons, radiologists, cardiologists, neurologists, and internists. Currently, the ARDMS is the only organization that administers certifying examinations in vascular technology. To earn the RVT credential, physicians with an MD or DO must pass two examinations covering vascular ultrasound physics, principles, and technology. As a prerequisite for the examinations, physicians should have 12 months of full-time clinical ultrasound or vascular experience. Full-time is defined as 35 hours per week for at least 48 weeks per year. The length of ultrasound or vascular experience must be documented in a letter either from the applicant s supervising physician or from the applicant him- or herself. Experience must be both didactic and clinical and is defined as, an individual employed in, or a student of, ultrasound/vascular technology in a clinical setting under the supervision of another physician and/or registered sonographer or vascular technologist. Clinical settings may include hospitals, clinics, or private practices. The ARDMS recommends that examination applicants be exposed to a minimum of 800 cases in each specialty area for which they are applying. The ARDMS further recommends that physicians document their continued competence as RVTs on at least a three-year schedule. To meet the continuing competence requirement, the ARDMS recommends physicians either accrue continuing medical education (CME) credits, pass an additional specialty exam in their current credential areas, or become registered in a different credential area. Those preferring to earn CME credits must accrue 30 credits in each successive three-year period to maintain active status. Successful completion of the two examinations conferring the RVT credential evidences a physician s knowledge of the following: 2 A supplement to Briefings on Credentialing 781/ Criteria reviewed 2006

3 Vascular Physical Principles and Instrumentation Ultrasound physics - definition of sound - propagation of sound in tissue - transducers - Doppler signal processing - Doppler instruments Ultrasound imaging - imaging principles - imaging artifacts Physiology and fluid dynamic - arterial hemodynamics - venous hemodynamics Physical principles - general - tissue mechanics/pressure transmission - plethysmography - pressure measurements - skin temperature Ultrasound safety and quality assurance - instrument performance - biological effects Vascular Technology Gross anatomy - central and peripheral arterial system - cerebral arterial and venous system - microscopic anatomy Test validation - statistics - measurements Therapeutic intervention - arterial, cerebral, and venous disease Arterial disease testing - patient history - physical examination (skin changes, palpations, auscultation) - noninvasive tests (Doppler velocimetry, pressures, plethysmography, Duplex imaging) - invasive tests (arteriography) A supplement to Briefings on Credentialing 781/ Criteria reviewed

4 Cerebral artery disease testing - patient history - physical examination (neurological, pulses, bruits) - noninvasive tests (indirect and direct tests) - invasive tests (arteriography) Venous disease testing - patient history - physical examination (skin changes, lymphedema, varicose veins, venous ulcers) - noninvasive tests (acute and chronic venous disorders) - invasive tests (venography) Other conditions - arteriovenous fistula - trauma - compartment syndrome - thoracic outlet syndrome ACR In ACR Standard for Performing and Interpreting Diagnostic Ultrasound Examinations, the American College of Radiology (ACR) states that, Physicians who perform or interpret diagnostic ultrasound examinations should be licensed medical practitioners who have a thorough understanding of the indications for ultrasound examinations as well as a familiarity with the basic physical principles and limitations of the technology of ultrasound imaging. In addition physicians should understand: alternative and complementary imaging and diagnostic procedures and be able to correlate the results of these procedures with sonographic findings; ultrasound technology and instrumentation, ultrasound power output, equipment calibration, and safety; and the anatomy, physiology, and pathophysiology of those organs or anatomic areas being examined. According to the ACR, physicians should provide evidence of training and requisite competence needed to successfully perform diagnostic ultrasound examinations. Training and competence can be achieved one of the following ways: Completion of an approved residency program which includes at least three months of diagnostic ultrasound training under the supervision of qualified individual(s), during which the resident should have been involved with the performance and interpretation of at least 500 diagnostic 4 A supplement to Briefings on Credentialing 781/ Criteria reviewed 2006

5 ultrasound examinations, which should include a broad spectrum of ultrasound uses. In addition, the physician should have successfully passed written and oral board certification examinations including sections pertaining to diagnostic ultrasound. If residency training did not include ultrasound, completion of appropriate fellowship or postgraduate training, during which the physician should have been involved with the performance and interpretation of at least 500 diagnostic ultrasound examinations, which should also include a broad spectrum of ultrasound uses. These should be performed under the direct supervision of a qualified physician who has met the criteria listed in the ACR Standard for Performing and Interpreting Diagnostic Ultrasound Examinations. Qualifications may also be fulfilled by those physicians who completed residency training prior to the existence of defined fellowships or residency training and board examinations in ultrasound. Such individuals shall have completed residency training prior to 1982, shall have performed and interpreted ultrasound examinations for at least 10 years, and shall have met requirements (a) and (b): a. Generation of film, videotape, or other hard copy records for studies performed; retention of such hard copies for an appropriate length of time consistent with hospital policy and state and federal laws; and generation of a written report for studies performed. b. When feasible, quality improvement projects should be undertaken and documented in an effort to continuously improve patient care. In the absence of formal fellowship, postgraduate training, or residency training, the documentation of clinical experience could be acceptable providing the following, in addition to requirements (a) and (b), could be demonstrated: c. At least two years of ultrasound experience during which at least 500 ultrasound examinations were performed or supervised and interpreted. The ACR recommends that physicians perform a minimum of 300 examinations per year in order to maintain competence in this procedure. The ACR states, however, that if there are an insufficient number of examinations to allow for compliance with the minimum standard, continuing qualification may take place if the results of monitoring and evaluation indicate A supplement to Briefings on Credentialing 781/ Criteria reviewed

6 acceptable technical success, accuracy of interpretation, and appropriateness of evaluation. The ACR also recommends physicians include continuing medical education in ultrasonography as appropriate to their practice. AIUM In its Training Guidelines for Physicians Who Evaluate and Interpret Diagnostic Ultrasound Examinations, the American Institute of Ultrasonics in Medicine (AIUM) states that, Physicians who evaluate and interpret diagnostic ultrasound examinations should be licensed medical practitioners who have a thorough understanding of the indications and guidelines for ultrasound examinations as well as a familiarity with the basic physical principles and limitations of the technology of ultrasound imaging. The AIUM further recommends that physicians demonstrate familiarity with the following: alternative and complementary imaging and diagnostic procedures; the correlation between the results of alternative and complementary procedures and ultrasound examination findings; ultrasound technology and instrumentation; ultrasound power output, equipment calibration, and safety; and the anatomy, physiology, and pathophysiology of those organs or anatomic areas being examined. According to the AIUM, physicians should have documented evidence of training and competence needed to successfully perform or interpret ultrasound examinations. Specifically, the AIUM recommends physicians meet at least one of the following criteria: Completion of an approved residency program, fellowship, or postgraduate training, which includes the equivalent of at least three months of diagnostic ultrasound training under the supervision of a qualified physician. A qualified physician is defined as one who, at a minimum, meets the criteria defined in these training guidelines. During this time the trainee should evaluate and interpret at least 500 diagnostic ultrasound examinations. It is expected that this number will be greater in specialties utilizing ultrasound in multiple anatomic regions. In the absence of formal fellowship or postgraduate training, documentation of clinical experience could be acceptable providing the following could be demonstrated: 6 A supplement to Briefings on Credentialing 781/ Criteria reviewed 2006

7 - evidence of 100 hours of American Medical Association (AMA) Category 1 CME activity dedicated to diagnostic ultrasound, and - evidence of being involved with the evaluation and interpretation of at least 500 diagnostic examinations within a three-year period of time. It is expected that in most circumstances, examinations will be under the supervision of a qualified physician. SVT, SDMS, SCIR, RSNA The Society for Vascular Technology, Society of Diagnostic Medical Sonographers, Society of Cardiovascular and Interventional Radiology, and Radiological Society of North America have no formal position on physicians performing or interpreting vascular ultrasound studies. Positions of other interested parties North Shore Medical Center, Salem, MA According to Christopher J. Choroszy, MS, RVT, technical director for the vascular ultrasound lab at North Shore Medical Center in Salem, MA, and a site inspector for the ICAVL, the North Shore Medical Center expects all clinicians, including physicians, to obtain the RVT credential within two years after joining the hospital s lab. The hospital also expects physicians to follow the ARDMS s requirements on maintaining the RVT credential, beginning with documenting their continued competence as an RVT on at least a three-year schedule. In order to maintain or update their skills, physicians should either accrue 30 CME credits in each successive three-year period, pass an additional ARDMS specialty exam in their current credential area, or become registered with the ARDMS in a different credential area. Choroszy explains that he has noticed more vascular laboratories seeking accreditation and, therefore, following the ICAVL standards. Says Chiroszy, Although peer recognition as a quality service and the potential issue of reimbursement are valuable interests for accreditation, it is my belief that the process of applying is as important. Although most labs comply with the ICAVL minimum standards, there is room to improve and fine-tune their service. In light of present health care trends and the patient-centered care models, continuous quality improvement should be a focus of all laboratories. CRC draft criteria The following draft criteria are intended to serve solely as a starting point for the development of an institution s policy regarding these procedures. A supplement to Briefings on Credentialing 781/ Criteria reviewed

8 Basic education: MD or DO Minimum formal training: Successful completion of an approved residency/fellowship training program in vascular surgery, radiology, cardiology, internal medicine, or neurology with at least three months of supervised diagnostic ultrasound training, or procurement of the ARDMS s registered vascular technologist credential. Required previous experience: Involvement in at least 500 documented and supervised vascular ultrasound examinations within the past three years. Note: As a prerequisite of the ARDMS s vascular ultrasound examinations, physicians must be exposed to at least 800 documented and supervised vascular ultrasound examinations within the last 12 months. Additional considerations The CRC recommends hospitals use their discretion in developing criteria for the maintainence of privileges in vascular ultrasound techniques. Hospitals should consider, however, requiring physicians to perform a minimum number of examinations per year and to obtain CME credits in order to demonstrate current competence in this evolving technology. The information contained in this document has been designed and is intended for use by hospitals and their credentials committees in developing their own local approaches and policies for various credentialing issues. These materials, opinions, and draft criteria should not be adopted for use without careful consideration, discussion, and additional research by physicians in local settings. The Credentialing Resource Center does not provide legal or clinical advice; for such advice, the counsel of competent individuals in these fields must be obtained. Reproduction outside the member s institution in any form is forbidden without prior written permission. 8 A supplement to Briefings on Credentialing 781/ Criteria reviewed 2006