Duplex

Utilize the appropriate duplex instrumentation with the appropriate frequencies for the vessels being examined.

• Typically, this is a high-frequency linear transducer with frequency ranging from 8-15 MHz.
• Display of both two-dimensional structure and motion in real-time
  • Doppler ultrasonic signal documentation
  • Spectral analysis with or without color Doppler imaging
• Digital storage of static images or cineloop is required.

Physiologic

Non-invasive physiologic studies require separate and distinct equipment from the Duplex ultrasound scanner. Instrumentation must allow the display and permanent recording of pressures with bi-directional Doppler analysis of blood flow, plethysmography and/or oxygen tension measurements.

• Continuous wave (CW) Doppler must provide:
  • Doppler frequencies appropriate for vessels examined
    • Typically range from 4-10MHz
  • Direction sensitive Doppler blood flow meter
  • Doppler waveform display with bi-directional flow capabilities
  • Audible output and permanent recording of Doppler waveforms
• Segmental limb plethysmography must provide:
  • Equipment capable of measuring small segmental volume changes and making permanent recordings of blood pressure measurements
  • Blood pressure cuffs of various sizes for each limb segment and digit evaluated
    • The recommended size is 20% wider than the limb diameter
• Pulse volume plethysmography (PVR) must provide:
  • Equipment capable of measuring small limb volume changes and saving permanent PVR waveforms
  • Capability to be calibrated before each exam
  • Blood pressure cuffs of various sizes for each limb segment and digit evaluated
• Photoplethysmography (PPG) must provide:
  • Electrical sensor for signal display
  • Capable of providing a permanent recording of PPG waveforms