Objective To observe changes in the stimulating effects of micro-invasion catgut embedding on different acupoints in healthy human over time and location

providing reference data for interval period of micro-invasion catgut embedding

and To study the feasibility of MRI T2-mapping technology used to measure stimulating effect of embedding material. Methods Before and after the left acupoints sanyinjiao（ SP 6） and zusanli（ ST 36） were treated with micro-invasion catgut embedding on 8 healthy subjects

8 echo sequence images were collected by using MRI scan. Sources of 8-echo sequence images were sent to the work station to get T2-mappings

and test the T2 value on T2-mappings

analyzing the characteristics of T2 value with time variation while comparing the difference of catgut absorption in SP 6and ST 36. Results In both two acupoints

T2 values on the 8thhour

the 3th

the 7thand the 14 thday after being catgut-embedded were all higher than those at the time before catgut-embedding（ P < 0. 01）

T2 valuse on the 21 th

the 28 thand the 35 thday after being catgut-embedded presented with no significant difference compared with the time before catgut-embedding（ P > 0. 05）. After being catgut-embedded

the peaks of T2 value appeared on the 3thday. Peak of T2 value in ST 36 was higher than that in SP 6

and T2 value in ST 36 decreased in a curve steeper than that in SP 6. It both took 21 days for T2 value in two acupoints to decrease to the level before catgut-embedding. Conclusion Catguts absorption period in ST 36 and SP 6 are the same. If applying micro-invasion catgut-embedding in acupoints on normal body limbs at the same condition

the catgut-embedding interval period is probably about 21 days. MRI T2-mapping technology could be applied to observe stimulating effect of embedding material after acupoint embedding.