Nanomaterials for Medical Imaging …
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[1]. Also, knowledge of the in vitro cell and drug interaction behavior is not as
similar to in vivo. To have a better understanding of the drug-disease interaction via
a non-invasive method, pre-clinical imaging tools are essential [2].
2 Medical Imaging
Medical imaging is a science, aid to look deep inside the body non-invasively to
obtain prognostic information about the disease region. Non-invasive internal structure imaging requires a specific region of electromagnetic (EM) spectrum based on
location in the human body and disease type. Different energy in EM would aid
in understanding the structures at different depths, either at a high or low resolution [3]. For instance, visible light has limited penetrating power when compared
to ultrasound and X-rays, but the resolution of the optical imaging is in the range
of nanometers (nm). Visible lights are generally used in skin, endoscopic, microscopic, and live-cell imaging applicable for clinics and research. Direct visualization, observation, and qualitative information are essential in understanding the clinical problems and research proofs [4]. Medical imaging technology is divided into
two different categories majorly as anatomical or structural, molecular and hybrid,
or multi-modal imaging. X-rays, computed tomography, ultrasound, and magnetic
resonance imaging are applicable for structural imaging. Whereas, positron emission
tomography and optical imaging are used as tools to obtain the molecular information at nanometer resolution [5]. Pre-clinical imaging is an effective technique to
provide valid information on the new drug developed at a laboratory level for further
commercialization. It is essential to diagnose cancer in its early stages, atrioventricular block in heart, and immunological diseases to understand the molecular
information of the diseased site. Recent progress in the preclinical non-invasive
imaging has led to the development of high-resolution systems to obtain qualitative
and quantitative information, drug treatment response, and to study the changes in
anatomical and molecular levels [6]. Three significant fields that widely use noninvasive imaging modalities are oncology, neurosciences, cardiology, and cardiovascular diseases. Various imaging modalities like micro-computed tomography (mCT),
micro-magnetic resonance imaging (mMRI), micro-optical imaging (mOI), microultrasound (mUS), and micro-positron emission tomography (mPET) are specifically
designed for small animal imaging and currently in use as shown in Fig. 2. The letter
prefix ‘micro (m)’ of the above imaging systems differentiates between clinical and
pre-clinical modalities. This ‘m’ stands for ‘micro’, which represents that imaging
system were specifically designed for small animals and not for clinical use [7]. The
above-mentioned imaging modalities are chosen based on the locations and the type
of disease. The fundamentals of the above imaging systems will be discussed in the
later sections of this chapter.
Several aspects of imaging would help to understand the anatomic and molecular details of different clinical departments, and few are listed below. First, noninvasive imaging in oncology involves estimating the structural changes in the tumor
337
[1]. Also, knowledge of the in vitro cell and drug interaction behavior is not as
similar to in vivo. To have a better understanding of the drug-disease interaction via
a non-invasive method, pre-clinical imaging tools are essential [2].
2 Medical Imaging
Medical imaging is a science, aid to look deep inside the body non-invasively to
obtain prognostic information about the disease region. Non-invasive internal structure imaging requires a specific region of electromagnetic (EM) spectrum based on
location in the human body and disease type. Different energy in EM would aid
in understanding the structures at different depths, either at a high or low resolution [3]. For instance, visible light has limited penetrating power when compared
to ultrasound and X-rays, but the resolution of the optical imaging is in the range
of nanometers (nm). Visible lights are generally used in skin, endoscopic, microscopic, and live-cell imaging applicable for clinics and research. Direct visualization, observation, and qualitative information are essential in understanding the clinical problems and research proofs [4]. Medical imaging technology is divided into
two different categories majorly as anatomical or structural, molecular and hybrid,
or multi-modal imaging. X-rays, computed tomography, ultrasound, and magnetic
resonance imaging are applicable for structural imaging. Whereas, positron emission
tomography and optical imaging are used as tools to obtain the molecular information at nanometer resolution [5]. Pre-clinical imaging is an effective technique to
provide valid information on the new drug developed at a laboratory level for further
commercialization. It is essential to diagnose cancer in its early stages, atrioventricular block in heart, and immunological diseases to understand the molecular
information of the diseased site. Recent progress in the preclinical non-invasive
imaging has led to the development of high-resolution systems to obtain qualitative
and quantitative information, drug treatment response, and to study the changes in
anatomical and molecular levels [6]. Three significant fields that widely use noninvasive imaging modalities are oncology, neurosciences, cardiology, and cardiovascular diseases. Various imaging modalities like micro-computed tomography (mCT),
micro-magnetic resonance imaging (mMRI), micro-optical imaging (mOI), microultrasound (mUS), and micro-positron emission tomography (mPET) are specifically
designed for small animal imaging and currently in use as shown in Fig. 2. The letter
prefix ‘micro (m)’ of the above imaging systems differentiates between clinical and
pre-clinical modalities. This ‘m’ stands for ‘micro’, which represents that imaging
system were specifically designed for small animals and not for clinical use [7]. The
above-mentioned imaging modalities are chosen based on the locations and the type
of disease. The fundamentals of the above imaging systems will be discussed in the
later sections of this chapter.
Several aspects of imaging would help to understand the anatomic and molecular details of different clinical departments, and few are listed below. First, noninvasive imaging in oncology involves estimating the structural changes in the tumor