Chemistry Reference
In-Depth Information
1.8
conclusIons
This chapter gives an overview of some of the most common imaging modalities and their basic principles. Their advantages
and disadvantages are summarised in Figure 1.25, and a more detailed comparison is shown in Table 1.4. Each imaging
modality has its own strengths and weaknesses for a particular area—for example, some techniques are more suited for
cellular, molecular, or anatomic imaging—and in fact, many of these techniques are complementary. These detection systems
differ in cost, availability, technical expertise needed, sensitivity, accuracy, and signal detection efficiency. Thus, the key
issues depend on the type of research questions being addressed.
However, advancement in imaging technology has enabled the creation of multimodal imaging platforms, which has
solved some of the dilemmas regarding the decision on what techniques should be used. At the same time, multimodal
imaging helps to resolve time and cost issues. Multimodal imaging modalities are an attractive solution, especially in
the area of diagnosis and in monitoring therapeutic responses; cT-MrI and cT-PET are already commonly used. The
developments of new techniques are continuously being explored, so it is likely that multimodal imaging modalities will
continue to be an area of interest, especially in the next decade. However, beneath this surface excitement around the
advancement of new technology, a key influencing element in imaging is still in the area of developing molecular design
and understanding their chemical properties. The demand for better imaging agents and probes parallels the development
of new instrumentation. The need to overcome and comply with the endless hurdles concerning biological barriers and
new mutagenic developments in diseases requires a constant need to review amplification strategies as well as to develop
new molecular designs for better probes and contrast agents. There will be a continued search for creating specialised
and specific probes propagated by endless, and as yet unknown, questions in areas such as oncology, physiology, and
pathology.
Imaging modalities
Advantages
Disadvantages
High sensitivity
numerous probes
Optical
Low spatial resolution
High spatial resolution
morphological and
functional imaging
Low sensitivity
long scans and
post-processing time
MRI
High sensitivity
quantitative
translational
Radiation
requires cyclotron
low spatial resolution
PET
Multiple probe imaging
numerous probes
Radiation
low spatial resolution
SPECT
Limited soft tissue
contrast
High contrast
CT
Real time
low cost
minimally invasive
Limited spatial
resolution
mostly morphological
US
FIgure 1.25
Pros and cons of different imaging modalities.
