Twinkling artifact on color Doppler ultrasound: an advantage or a pitfall?

The twinkling artifact (TA) or color comet-tail artifact is characterized by a rapidly changing mixture of red and blue color Doppler signals. Even though many diseases and clinical conditions have been shown to produce this artifact, its source is not clearly understood yet. The TA may provide additional information to gray-scale ultrasound findings in several clinical situations. However, there may be pitfalls to keep in mind. We must first be aware of the TA to benefit from the advantages and avoid the pitfalls. In this review, we aim to give practicing radiologists an overview of the mechanisms and clinical applications of the TA by illustrating sample cases we have encountered.