The detection of sources responsible for coherent components in ultrasound signals, has been a difficult task. In this work, we explore the idea of using phase coherence as a measure of the level of structured regularity present in the scattering medium. If the scattering sites are located randomly, then the reflected signal should be incoherent. This is the case of purely diffuse scattering. If, however, there is structure in the scattering medium, then the reflections from those sites will have some non-random phase relationship. In this work, the phase distribution is characterized as follows. For each demodulation frequency, we plot the power as a function of phase. This is computed for all frequencies in the usable bandwidth of the transducer. For each frequency, the power is uniformly distributed across phase from 0 to 2 (pi) for a purely incoherent signal. Systematic deviations from the uniform distribution may indicate the presence of coherent scattering components. This approach was first verified using simulation data, then applied to two sets of clinical ultrasound data. We have achieved good classification performance (area under the ROC curve, Az equals 0.86 +/- 0.04) using two features extracted from this analysis of phase.