Injectable biomaterials vascular applications

Abstract This chapter focuses on the vascular applications of injectable biomatetials. Two clinically relevant vascular conditions, cerebral arteriovenous malformations and intracranial aneurysm, will be discussed in terms of endovascular embolization. This chapter then outlines available embolic materials used to treat each condition, as well as highlighting new injectable biomaterials developed for embolization purposes. 

Shape memory polymers make up another class of injectable biomaterials for vascular applications, yet are relatively new in the field of endovascular embolization. Shape memory polymers are chemically structured so that they are able to reversibly take on a different physical shape in response to some stimuli (Small et al, 2007). Usually these different shapes include a compact form and an expanded form of the polymer. In the case of endovascular embolization, the expanded polymer can be pre-formed to fit specific contours of an individual aneurysm (Ortega et al, 2007). Upon interacting with some type of stimuli, such as heat or cold, the material is compacted into a shape that can be delivered through a microcatheter. The process of using shape memory polymers to embolize an aneurysm is shown in Fig. 7.5, along with samples of expanded SMPs (Ortega et al, 2007). 

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