OBJECTIVETo in vivo dynamically observe the time-effect characteristic of local stimulating effect on acupoints after micro-invasion embedding, which could provide references for the interval period of micro-invasion embedding.

METHODSWith magnetic resonance imaging (MRI) technique, the local T2WI fat-suppression images and T2 Mapping 8-echo sequence images were collected at multiple time points from 8 healthy subjects who received embedding at left Sanyinjiao (SP 6).After the 8-echo sequence images were transformed into T2 Mapping images by using software FuncTool, the T2 average value of embedding area was measured, and the changes of local signal strength of T2WI fat-suppression images and T2 average value along with time after embedding at left Sanyinjiao (SP 6)were analyzed.

RESULTSCompared before embedding, the signal strength of local T2WI fat-suppression images and the T2 average value began to increase 8 h after being embedded(<0.01); the signal strength of T2WI fat-suppression images and the T2 average value were significantly increased 3 d and 7 d after being embedded(all<0.01);the signal strength of local T2WI fat-suppression images and the T2 average value 14 d after being embedded were lower than those at previous 2 time points, but higher than those before embedding(both<0.01); 21 d, 28 d and 35 d after embedding, the signal strength of local T2WI fat-suppression images and the T2 average value were similar to those before treatment (all>0.05).

CONCLUSIONSAfter micro-invasion embedding at Sanyinjiao (SP 6), the stimulation effect period on acupoint is approximately 21 days.When applying micro-invasion embedding under similar condition at acupoints which has similar structure as Sanyinjiao (SP 6), the interval period of embedding could consider 21 days as a reference.