The use of lasers to improve knot security

1 Preliminary study involving polyester film and suture and a single laser power 

The results presented in Fig. 12.15b indicate that with exposure the KHF (strength) first increased (-17%), reaching a maximum at about 1.2 J, and then decreased. The gain in knot strength was about 17%. The slippage 

2 Follow-up study involving several sutures and sizes and laser powers 

The work presented in Section 12.7.1 was limited to one type of suture, size and power, and the suture used was uncoated braided polyester that tended to develop a secure knot in the 1=1 configuration. Tlie previously unknown effects of a change in power, and suture material and size on knot tensile properties were determined in this study. The laser used was one that was conunerdaUy available and generally found in operating theatres. 

15 Effect of the energy of exposure on the strength of 3-0 Mersilene suture material (a) suture without knot and (b) suture containing two-throw (1=1) knot.  

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