In this chapter we introduce some of the latest applications of biomaterials in medical technology. Previous chapters have concentrated on therapeutic processes, either by pharmaceutical components, regenerative medicine processes or implantable devices. All clinically successful therapeutic measures require good diagnosis of the patient’s condition. Although the doctor’s intrinsic clinical skills are extremely important, the need for very accurate, instrument-assisted, diagnosis, with good spatio-temporal resolution, is becoming increasingly significant. This is because early and precise diagnosis is essential if the doctors are able to use the most effective treatments for cancer, degenerative disease and other critical issues. Medical technologies have always played some role in diagnosis, but have rarely, until recently, involved the use of biomaterials. Most techniques are concerned with the application of some physical energy to the affected tissues and organs, using X-rays and other ionizing radiations, ultrasound and light, for example, and detecting the responses of the tissues to that energy. Conventional methods often provide relatively poor contrast between different types of tissues (and any lesions they contain), usually with restricted spatial resolution. They usually produce anatomic rather than functional information. The essential rationale for the use of biomaterials in these imaging systems is to enhance the contrast that can be seen, especially by accentuating differences between the response of different types of tissues and between different disease states. Most of these biomaterials are used in nanoparticulate form. Their applicability is controlled by their differential responses to the applied energy and by their handling within the tissues of the body.

Anatomical and functional imaging

The majority of this book so far has been concerned with the therapeutic methods that may be used to treat diseases and conditions of the human body, where those methods significantly rely on the use of biomaterials. Before any therapy can be considered, it is necessary for the clinicians involved to be aware, as accurately as possible, of the nature of the disease or condition that is affecting the patient in question. For very many years, this process of identifying what is wrong, known as diagnosis, was informed by the skilled observations of the clinicians and the measurement of some relevant physiological parameters such as temperature, heart rate and blood pressure.