Characterization of deqi sensation and acupuncture effect

Acupuncture stimulation elicits deqi, a composite of unique sensations. According to traditional Chinese medicine (TCM), deqi experienced by patients is often described as suan (aching or soreness), ma (numbness or tingling), zhang (fullness, distention, or pressure), and zhong (heaviness) and is felt by the acupuncturists (needle grasping) as tense, tight, and full. It is believed that deqi may be an important variable in the studies of the mechanism and efficacy of acupuncture treatment. In recent years, great efforts have been made to understand deqi, which include a couple of questionnaires to qualify and quantify deqi sensations, neuroimaging studies of deqi and acupuncture, physiological mechanisms of deqi, and the relation between deqi and clinical efficacy. However, many problems need to be resolved, and more researches are required to be made in the future.