Page 92 - ITPS-7-3

INNOSC Theranostics and
Pharmacological Sciences Medical imaging technology

and accounts for about 20% of the population’s radiation Available statistics indicate that the levels of ultrasound
exposure. The annual number of head CT examinations exposure used in diagnosis do not cause harm to the
accounts for about 60% of total examinations. In addition, human body. Due to its non-destructive and non-invasive
nearly half of the head CT examinations include both nature, ultrasound imaging has been increasingly used in
plain and enhanced scans, doubling the radiation dose. clinical practice. This is especially true for sensitive areas,
Therefore, the potential radioactive hazards of CT cannot such as fetal and eye examinations, where ultrasound is
be ignored. For example, if a pregnant woman is exposed to much safer than X-ray. However, even ultrasound imaging
radioactive lead during the 3 month of pregnancy, it may should be used with caution for embryos in the early stages
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cause serious consequences such as fetal hydrocephalus, of development.
hematopoietic system defects, and skull defects. Therefore,
when pregnant women undergo CT examination, they 5. Development trends in medical imaging
need to place an X-ray protection device on the abdomen technology
to avoid and reduce the risk of fetal malformations. The future development trend of modern medical imaging
During operation, the MRI instruments can generate aims to improve information transmission methods,
strong static magnetic fields, ultra-low-frequency and improve information transmission efficiency, create new
highly variable electromagnetic fields, and radiofrequency methods of information expression, and improve image
fields. Radiofrequency fields are not an important part display quality on the premise of ensuring personnel safety.
of MRI protection. At present, MRI protection mainly The ultimate medical significance is to more accurately
relies on shielding from static magnetic fields and ultra- detect initial pathological changes in human tissues,
low-frequency high-variable magnetic fields, especially providing a basis for early diagnosis and treatment. Medical
static magnetic fields. In addition, MRI is an expensive imaging technology is evolving from analog to digital
and sophisticated equipment that usually requires an air- images; from two-dimensional images to three-dimensional
conditioning system, resulting in higher indoor radon images; from local images to overall images; from macro
concentrations. To prevent the impact of magnetic fields images to micro images; from static images to dynamic
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on the human body, magnetic field shielding is commonly images; from morphological to functional images; and
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used, and methods such as copper mesh are used for from single to integrated images. This includes acquiring
degaussing. However, MRI is generally much less harmful multi-temporal (dynamic) images, multi-dimensional
to the human body than CT. images, multi-parameter images, multi-modal images, and
multiple clinical indicators (including lesion examination,
Nuclear medicine imaging, also known as radioisotope characterization, organ function assessment, and blood
imaging, also causes ionizing radiation exposure in the flow estimation), as well as treatment aspects (including
human body. In X-ray photography, although the intensity three-dimensional positioning, volume calculation, and
of radiation is relatively high, the patient is only exposed surgical planning) and multi-regional display observation.
for a short period of time. In contrast, the concentration Improvements can be made from the following aspects:
of radioactive materials used in radioisotope imaging is (i) Developing ultra-high-resolution phenomenon
very low, but the exposure of radiopharmaceuticals to the systems
human body continues for a period of time until they are (ii) Enhancing the performance of imaging equipment
excreted from the body or decay. Therefore, an important and adding new functions. For instance:
factor to consider when selecting a radioactive material • MRI: Incorporating magnetic resonance
formula is the requirement for a short half-life. spectroscopy imaging 13
When evaluating the ionizing radiation damage • Ultrasound: Implementing color blood flow
caused by X-ray and radioisotope imaging in the human imaging, intracavity ultrasound imaging, digital
body, attention should be given to both the intensity and processing for three-dimensional image display,
duration of exposure. In X-ray imaging, the radiation and ultrasound CT
intensity is relatively high, but the exposure time is short. • CT: Continuing to improve spatial resolution and
Conversely, although the concentration of radioactive scanning speed, focusing on studying changes in
isotope materials is low, the exposure to the human body disease metabolism, and reducing costs.
lasts for a longer period until it is excreted or decays. Medical images can intuitively display the anatomical
Therefore, during X-ray examinations, the dose to the structure, form, and functions of various tissues and organs
human body should be minimized as much as possible. inside the body, making them indispensable in clinical
When selecting radioactive materials, their short half-life diagnosis. However, existing imaging examinations cannot
should be considered to reduce prolonged exposure. yet fully meet clinical diagnostic needs, as any single

Volume 7 Issue 3 (2024) 8 doi: 10.36922/itps.3360