Characterizing Triphasic, Biphasic, and Monophasic Doppler Waveforms

Doppler waveform analysis is a fundamental part of evaluating peripheral arterial disease. Waveform characteristics are traditionally defined as multiphasic (triphasic, biphasic) and monophasic. The purpose of this investigation is to evaluate whether sonography professionals correctly classify waveforms into these three categories. Thirty Doppler waveforms (15 continuous-wave [CW] and 15 pulsed-wave [PW] Doppler) were obtained from patients with previous noninvasive peripheral arterial evaluations. Participating readers were asked to interpret waveforms as triphasic, biphasic, or monophasic using standard definitions. “Other” was used to classify waveforms whose morphology could not be determined or accurately classified as triphasic, biphasic, or monophasic. Because multiphasic waveforms with pandiastolic flow have been associated with biphasic and monophasic waveform terminology, answer key responses were based on waveform descriptors used by interpreters of the originating noninvasive evaluation. There were a total of 97 participants, and of all Doppler waveforms, 73% were correctly identified (75% CW and 71% PW). Participants training or specializing in medical sonography misidentified an average of 27% triphasic, biphasic, or monophasic CW and PW Doppler waveforms and correctly interpreted more CW than PW waveforms. Because there is considerable variability among sonography professionals and educators in defining and classifying peripheral arterial waveforms, this issue deserves higher priority.