Documents / Report
This Defense Intelligence Agency reference document, dated 7 January 2010 and prepared under the Acquisition Threat Support series, surveys biomaterials used in medicine. It covers biocompatibility, biosensor membranes, silicones, Teflon, biodegradable polymers, hydrogels, titanium, bioceramics, tissue constructs, cardiovascular stents, contact lenses, drug delivery and dialysis. It concludes that biomaterial performance underlies many medical devices, that the industry is slow to adopt new materials because of testing costs, and that innovation mainly involves new applications of established materials.
UNCLASSIFIED/,CFfHl 8FFl6ltl1ls Wlil 8Pll!!JJ A problem most materials cause when in blood contact is that they trigger the rapid formation of thrombus (an aggregation of blood cells). The formation of a thrombus is dangerous, as the thrombus could either adhere to the surface of the biomaterial or be detached. If a thrombus is detached, it can travel in the blood stream and occlude smaller vessels in the brain (called a stroke) or lungs (called an embolism). Some small-diameter vascular grafts ( < 5-millimeter internal diameter) and prostheses for reconstruction of diseased veins are "safe" only when anticoagulant drugs are used. In addftion to thrombus formation, biomaterials can become colonized with infection- causing bacteria. Some microorganisms found in hospitals are extremely resistant to antibiotic therapy, and infections cannot be fully resolved until the biomaterial is removed. This is particularly a problem with hip and knee implants, where there is poor blood flow near the joint and the body's immune system has limited access. Methicillin- resistant staphylococcus aureus infections are dangerous in these situations. The high tolerance of the body for woven and formed Teflon allows it to be used as a flexible patch material for other blood-contacting surfaces, in addition to blood vessels. For example, Gore, Inc., makes a Teflon-based material that is used to patch holes in the heart of infants born with atrial septa! defects. Figure 23 is an artist's conception of how the patch is inserted into the hole in the atrial wall using a catheter. 17 Figure 23. Illustratlon of Treatmeni of an Atrial Septal Defe<:t Using a Teflon-Based Product Manufactured by Gore, Inc. UNCLASSIFIED//fOft 8ffl61"1k Y&i ,HIia¥
Not linked to a story yet.
Report, from the dia collection. The PDF is mirrored here; the original link is above. 32 pages are in the text index: search them above, or from the library's search.