[Time-effect reaction observation of micro-invasion embedded poly glycolide-co-lactide suture in Sanyinjiao (SP6) in healthy subjects by using magnetic resonance]

Abstract

Objective: To observe the time-effect of stimulation of the embedded poly glycolide-co-lactide (PGLA) suture in Sanyinjiao (SP6) area in normal human body, so as to provide an experimental evidence for clinical application of micro-invasion suture-embedding at an appropriate interval.

Methods: A total of 8 healthy volunteer students (3 boys and 5 girls, ranging in age from 24 to 27 years) were recruited in the present study. A piece of sterilized PGLA suture was implanted into the left SP6 using minimally invasive surgery after strict local skin disinfection. The fat-suppression T2 weighted magnetic resonance images (MRI, displaying local lesion after eliminating interference of fat tissue signals), and T2 mapping 8-echo train images were acquired before and 8 h, 3, 7, 10 and 14 days after PGLA suture embedment by using a MR imaging system. After transformation of the T2-mapping 8-echo train images into T2-mapping images by using a relevant software, the T2 values (meaning the relaxation time of the local muscle) of the left SP6 were measured, followed by analysis of the signal intensity of T2 weighted fat-suppression images and T2 values at different time-points.

Results: Before the suture embedding, no abnormal signals were found in the signal intensity of T2 weighted fat-suppression images. After PGLA suture embedment, the local signal intensity of T2WI fat-suppression images was relatively increased at the 8^th h, and on day 3, 7, 10 and 14 relevant to pre-embedment, but gradually atte-nuated on day 10 and 14. The T2 values were significantly increased at the 5 time-points of post-embedment (all P<0.01), but without significant differences among the 8^thh, the 3^rd and 7^thd (P>0.05), and being markedly lowered on day 14 relevant to day 7 (P<0.01) in spite of being still markedly higher than that of pre-embedding (P<0.01).

Conclusion: The signal intensity of T2 weighted fat-suppression images and T2 values acquired from PGLA-suture-embedded SP6 acupoint area in healthy subjects may keep at least for 2 weeks, suggesting that the stimulating reaction of suture-embedment persists more than 14 days. Hence, when a micro-invasion embedding with PGLA suture performed, the interval of two weeks would be appropriate.

Keywords: Micro-invasion embedding; Poly glycolide-co-lactide (PGLA) suture; San-yinjiao (SP6); Stimulating effect; Time-effect.