"Tissue-drag" with polyglycolic acid (Dexon) and polyglactin 910 (Vicryl) sutures in strabismus surgery.

The new absorbable synthetic sutures, polyglycolic and (Dexon) and Polyglactin 910 (Vicryl), are excellent sutures for strabismus surgery, but they have a bothersome tendency to attract adjacent tissue (tissue-drag). This difficulty is found especially with the 5-0 size suture, less so with the 6-0 size suture, and minimally with the 7-0 size suture. The presence and number of short, stubbly, protuberant strands (hooklets) seen on the surface of these sutures under high magnification correlates with the lack of ease with which the sutures pass through tissue. Other factors involved in tissue-drag include the crevices between braids in these sutures and the fiber-tissue friction due to the innate nature of the suture materials. Sutures which pass with ease through tissue, such as catgut and nonabsorbable sutures, are seen to have smooth surfaces under high magnification. Coating the 5-0 and 6-0 Dexon and Vicryl sutures to smooth their surfaces and reduce tissue-drag was ineffective with isotonic saline solution, minimally to moderately effective with glycerine and with methylcellulose and polyvinyl alcohol solutions, but highly effective with peanut and sesame oils. Though tissue-passage of Dexon and Vicryl sutures was much improved by coating with oil and entirely satisfactory, it still was not quite as good as with catgut. Clinically, the oil did not compromise the knot security or ease of handling of the sutures. No unusual postoperative reaction was seen with the use of the oiled sutures. Although oiling the synthetic absorbable sutures at time of surgery is effective, we recommend that suture manufacturers reduce the tissue-drag of synthetic absorbable sutures either by smoothing the surface in the manufacturing process or by developing an absorbable coating applied to the sutures during manufacture.