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The IAC Standards and Guidelines
for Vascular Testing Accreditation

 

Click here for a printer-friendly PDF of the Vascular Testing Standards

Part B:
Examinations and Procedures

Section 1B: Extracranial Cerebrovascular Testing

STANDARD – Indications

 

1.1B         Extracranial cerebrovascular testing must be performed for appropriate clinical indications

 

1.1.1B         The indication for testing must be documented prior to performing the examination.

 

(See Guidelines below for further recommendations.)

 

STANDARD – Equipment

 

1.2B         Equipment must provide accurate data.

 

1.2.1B         Imaging Equipment – Duplex ultrasound with color flow Doppler must be provided with:

 

1.2.1.1B        imaging frequencies appropriate for the structures evaluated;

 

1.2.1.2B        Doppler frequencies appropriate for the vessels evaluated;

 

1.2.1.3B        range-gated spectral Doppler with the ability to adjust the depth and position of the range gate within the area of interest;

 

1.2.1.4B        a Doppler angle which is measurable and adjustable;

 

1.2.1.5B        a visual display and a permanent recording of the image; and

 

1.2.1.6B        a visual display, an audible output, and a permanent recording of the Doppler waveform and corresponding image which includes the Doppler angle.

 

1.2.2B         Equipment Quality Control

 

1.2.2.1B        Equipment used for diagnostic testing must be maintained in good operating condition.

 

1.2.2.2B        Equipment maintenance must include, but is not necessarily limited to:

 

i.            recording of the method and frequency of maintenance of all imaging equipment and non-imaging equipment;

ii.          establishment of and adherence to a policy regarding routine safety inspections and testing of all facility electrical equipment;

iii.         establishment of and adherence to an equipment cleaning schedule that includes routine cleaning of equipment parts, including filters and transducers, according to specifications of the manufacturer.

 

(See Guidelines below for further recommendations.)

 

STANDARD – Protocols

 

1.3B         Each examination performed in the facility must have a written protocol. The protocol must include:

 

1.3.1B         equipment to be used for each examination;

 

1.3.2B         elements of proper technique (also see STANDARD – Techniques);

 

1.3.3B         anatomic extent that constitutes a complete examination includes the evaluation of the entire course of the acceptable portion of each vessel;

 

1.3.3.1B        bilateral testing is considered a complete examination.

 

1.3.3.2B        variations in technique following vascular intervention.

 

1.3.3.3B        variations in technique and documentation for limited examinations.

 

1.3.4B         documentation that must be acquired for normal examinations and the additional documentation that must be acquired to describe abnormalities, if present (also see STANDARD – Documentation);

 

1.3.5B         a description of how color Doppler or other flow imaging modes (e.g., power Doppler) are used to supplement grayscale imaging, spectral Doppler and velocity measurements.

 

STANDARD – Techniques

 

1.4B         Appropriate techniques must be used for the evaluation of the extracranial cerebrovascular system to assess for the presence of any abnormalities and to document their severity, location, extent and whenever possible etiology.

 

1.4.1B         Elements of proper technique include, but are not limited to:

 

1.4.1.1B        performance of an examination according to the written, facility specific protocol;

 

1.4.1.2B        proper patient positioning;

 

1.4.1.3B        patient preparation;

 

1.4.1.4B        appropriate equipment and transducer selection;

 

1.4.1.5B        appropriate transducer positioning;

 

1.4.1.6B        proper sample volume size and positioning;

 

1.4.1.7B        optimization of equipment gain and display settings;

 

1.4.1.8B        a spectral Doppler angle of 60 degrees or less with respect to the vessel wall and/or direction of blood flow when measuring velocities;

 

1.4.1.9B        proper measurement of spectral velocities as required by the protocol;

 

1.4.1.10B        identification of vessels by imaging and Doppler.

 

STANDARD – Documentation

 

1.5B         Each examination performed in the facility must provide documentation as required by the protocol that is sufficient to allow proper interpretation, including but not limited to: 

 

1.5.1B         grayscale images;

 

1.5.2B         color Doppler images;

 

1.5.3B         Doppler waveforms;

 

1.5.4B         velocity measurements;

 

1.5.5B         other images and waveforms as required by the protocol;

 

1.5.6B         other measurements as required by the protocol.

 

1.6B         Abnormalities will require additional images and waveforms that demonstrate the severity, location, extent and whenever possible etiology of the abnormality present.

 

1.6.1B         Areas of suspected stenosis or obstruction must include representative Doppler waveforms and velocity measurements recorded at and distal to the stenosis or obstruction

 

1.7B         Extracranial Cerebrovascular Documentation

 

1.7.1B         Long axis grayscale images must be documented as required by the protocol and must include at a minimum:

 

1.7.1.1B        common carotid artery;

 

1.7.1.2B        carotid artery bifurcation;

 

1.7.1.3B        internal carotid artery.

 

1.7.1.4B        carotid artery stent (if present) including proximal and distal ends.

 

 

1.7.2B         Spectral Doppler waveforms and velocity measurements must be documented as required by the protocol and must include at a minimum:

 

1.7.2.1B        proximal common carotid artery;

 

1.7.2.2B        mid/distal common carotid artery;

 

1.7.2.3B        proximal internal carotid artery;

 

1.7.2.4B        distal internal carotid artery (as distal as possible);

 

1.7.2.5B        one site in the external carotid artery;

 

1.7.2.6B        one site in the vertebral artery.

 

1.7.2.7B        carotid artery stent (if present).

i.            native artery at the proximal end of the stent;

ii.           proximal stent;

iii.          mid stent;

iv.           distal stent;

v.            native artery at the distal end of the stent;

 

                                                Comment: Limitations of the study must be documented in the final report.

 

1.7.3B         Abnormalities require additional images, waveforms and velocity measurements.

 

STANDARD – Procedure Volumes

 

1.8B         The annual procedure volume must be sufficient to maintain proficiency in examination techniques and interpretation.

 

1.8.1B         indication for the examination;

 

1.8.2B         technologist performing the examination;

 

1.8.3B         examination(s) performed;

 

1.8.4B         examination findings;

 

1.8.5B         physician interpreting the examination.

 

 

Section 1B: Extracranial Cerebrovascular Testing
Guidelines

 

1.1B                When available, appropriateness criteria published by medical professional organizations should be utilized.

Comment: An accepted indication is generally written by the referring health care provider. In some instances it can only be assessed at the time of the examination.

 

1.2.2.2B         The cleaning schedule for each system will depend on the degree of use and should be frequent enough to allow for accurate collection of data.

 

1.3B         The protocol should include the indications for a limited examination and the descriptions of the limited examination. Separate limited examination protocols may also be written.

 

 1.8B             The annual procedure volume should be sufficient to maintain proficiency in examination techniques and interpretation.

 

      In general, a facility should perform a minimum of 100 complete examinations annually.