Page 90 - ITPS-7-3

INNOSC Theranostics and
Pharmacological Sciences Medical imaging technology

uterus, appendages, prostate, testicles, and other organs, brain function.
accurately measuring blood flow, and the size, texture, and The gamma camera consists of three parts: a probe,
boundaries of stones and masses. In addition, it can be used an electronic circuit, and a display device. The gamma
in clinical interventional examination and treatment. camera can observe all parts of an entire organ image
3.4. Nuclear medicine imaging simultaneously in a short period of time. It has high
sensitivity, can image at 1 time, and can conduct continuous
The nuclear medicine imaging system, also known as and dynamic observation of the organ. Cameras equipped
the radionuclide imaging system, detects rays emitted by with electronic computers are most suitable for quantitative
radionuclides in the human body. The image signal reflects analysis and rapid continuous dynamic analysis of organ
the concentration distribution of the radionuclide and and tissue imaging, significantly improving the diagnostic
displays both morphological and functional information. effect of in vitro imaging and being valuable for diagnosing
Nuclear medicine imaging is essentially different from cardiovascular diseases, tumors, and other conditions.
other imaging modalities. Its images depend on factors
such as blood flow, cell function, cell number, metabolic The SPECT probe is a gamma camera that rotates
activity, and excretion and drainage of organs or tissues, 360° around an organ of the patient. During rotation, it
rather than changes in tissue density. It is a functional collects a frame of images at specific angles. After computer
image, and the clarity of the image mainly depends on processing, the images are superimposed, and the filtered
the functional status of the organ or tissue. Since changes back-projection method is used to reconstruct cross-
in functional metabolism during disease processes often sectional images from a series of projections. From the
occur before morphological changes, nuclear medicine three-dimensional information of transverse tomographic
imaging is considered one of the earliest diagnostic images, sagittal, coronal, and arbitrary oblique tomographic
methods of significant value. images can be obtained through image recombination.
SPECT combines the characteristics of both gamma
Nuclear medicine imaging technology is an imaging cameras and CT, allowing for stereotaxic positioning and
method that captures the radioactive differences between dynamic observation of changes in local function and
normal and diseased tissues within and outside the organ. metabolism of organs. The detection rate of lesions and the
Nuclear medicine imaging examination first involves clarity of imaging are better than those of gamma cameras.
selectively administrating certain radioactive drugs (trace, 10
PET is a relatively advanced clinical examination
accurately targeted, safe, and harmless enhanced tracers) imaging technology in the field of nuclear medicine. The
to the human body. These drugs accumulate in specific general method involves labeling a substance necessary for
organs or participate in certain bodily processes. During the metabolism of biological life, such as glucose, protein,
these metabolic processes, radionuclides emit gamma rays, nucleic acid, or fatty acid, with a short-lived radionuclide
which then photographed by nuclear medicine imaging (such as fluorine-18 or carbon-11), and then injecting it
instruments photograph to get images on the concentration into the human body. The accumulation of this substance in
distribution and metabolic process of these radionuclides metabolism reflects the metabolic activities of life, thereby
in organ tissues. Nuclear medicine imaging examination achieving the purpose of diagnosis. The main substance
methods are widely used in medicine. The primary used in hospitals is fluorodeoxyglucose, commonly
difference between it and XCT is that the ray source of abbreviated as FDG. Its detection mechanism relies on
XCT is outside the body, while the ray source of nuclear the fact that the metabolic status of different tissues varies.
medicine imaging is inside the body. Nuclear medicine In high-metabolizing malignant tumor tissues, glucose
imaging technology can obtain not only anatomical images metabolism is strong, and there is greater accumulation.
of human organs but also physiological, biochemical, These characteristics can be reflected through images,
pathological processes, and functional images. Using enabling the diagnosis and analysis of lesions.
mathematical algorithms, a three-dimensional “transparent
human body” image showing the density distribution of 3.5. Near-infrared imaging
radioactive elements in the body can be reconstructed in The infrared thermal imaging device uses an infrared
a computer. detector to detect infrared rays radiated from the surface
At present, the main technologies for nuclear medicine of the human body and convert them into electrical
imaging include gamma photography, single-photon signals. The infrared camera acquires the video signal,
emission computed tomography (SPECT), and PET. The which is then amplified, filtered, and sent to a computer
latter two are collectively called emission CT, with PET for imaging. This technology can be used to diagnose
also becoming a primary technical means for studying temperature-related diseases, such as superficial tumors,

Volume 7 Issue 3 (2024) 6 doi: 10.36922/itps.3360