Shape sutures

Medical applications of biodegradable shape memory polymers include their use for removing blood clots formed during strokes. Preshaped foams can be used to fill cranial aneurisms. Loosely tied sutures made from fibers that have been stretched at 50 °C will tighten when heated just above room temperature. 

The implant consists of a tablet-shaped ganciclovir reservoir. The drag is initially completely coated with poly(vinyl alcohol) (PVA) and then coated with a discontinuous film of hydrophobic, dense poly (ethylene-co-vinyl acetate) (EVA). Both polymers are nonerodible and hydrophobic (the PVA used in the implant is cross-linked and/or high molecular weight, to ensure it does not dissolve when exposed to water). The entire assembly is coated again with PVA to which a suture tab made of PVA is attached (Figure 4.5). 

Stimuli-responsive polymers have gained increasing interest and served in a vast number of medical and/or pharmaceutical applications such as implants, medical devices or controlled drug delivery systems, enzyme immobilization, immune-diagnosis, sensors, sutures, adhesives, adsorbents, coatings, contact lenses, renal dialyzers, concentration and extraction of metals, for enhanced oil recovery, and other specialized systems (Chen and Hsu 1997 Chen et al. 1997 Wu and Zhou 1997 Yuk et al. 1997 Bayhan and Tuncel 1998 Tuncel 1999 Tuncel and Ozdemir 2000 Hoffman 2002 en and Sari 2005 Fong et al. 2009). Some novel applications in the biomedical field using stimuli-responsive materials in bulk or just at the surface are shape-memory (i.e., devices that can adapt shape to facilitate the implantation and recover their conformation within the body to... 

Shape-Memory Self-retaining Sutures, Methods of Manufacture, and Methods of Use, 2011. US Patent 20110125188 Al. 

Techniques have been developed for termino-terminal anastomoses with KL-3 adhesive covering, an incomplete eversion of the mucous membrane and the use of a loop-shaped intestinal suture [451, 453]. Such anastomoses are simple to make and lack the disadvantage inherent in an operation carried out by the routine method the development of an adhesive process in the region of anastomosis with subsequent deformation of the anastomosis because of eversion of the mucous membrane. It was noted that the KL-3 adhesive, used for the peritonization of the zone of classic everted anastomosis, prevents the development of adhesive processes and the deformation in the region of the anastomosis reliably restricts the everted mucous membrane from the organs of the abdominal cavity, consohdates the zone of anastomosis, and induces minimal infiammatoiy response in the adjacent tissues. 

Potential uses of shape memory polymers in medicine are to prepare sutures that have a rigid enough composition to provide for... 

Biodegradable polymers play a prominent role in the family of SMPs. This is due to their biodegradabdity because in many of the medical applications the related devices with SM function (e.g., sutures, catheters, stents) should be present only temporarily in the human body. The other, not less important, aspect is that the switch temperature for shape programming (Tf.j. g) can well be matched with that of the body. 

Absorbable polymer sutures for wound closure appeared in the 1970s. These PGA-based sutures registered tremendous growth, a trend which continues even now. Since the wound should be closed for healing, which can be easily triggered by a transition from temporary to permanent shape, the interest turned to smart sutures making use of the SM behavior. The attribute smart may be related to the antimicrobial and healing activities, set by the incorporation of suitable additives into the sutures [80, 81]. 

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