Which of the following statements is/are true regarding the use of duplex scanning as a means to follow and monitor bypass grafts?
A. Duplex scanning is accurate and cost effective
B. A localized increase in systolic velocity greater than 25% compared to adjacent segments in the graft identifies a diameter reduction of at least 50%
C. Peak systolic velocities should be less than 40 cm/sec throughout the graft
D. Arterial venous fistulas associated with in situ bypass grafts are difficult to detect with a duplex scanner
Answer:A
Which of the following statements is/are true regarding the use of duplex scanning as a means to follow and monitor bypass grafts?
A. Duplex scanning is accurate and cost effective B. A localized increase in systolic velocity greater than 25% compared to adjacent segments in the graft identifies a diameter reduction of at least 50% C. Peak systolic velocities should be less than 40 cm/sec throughout the graft D. Arterial venous fistulas associated with in situ bypass grafts are difficult to detect with a duplex scanner