In recent years, the widespread use of radiological diagnostic and therapeutic equipment—especially CT scanners and medical linear accelerators—has become a crucial technical means for early diagnosis and timely treatment of patients. According to data, more than 1.2 billion people in China undergo radiological procedures annually. Therefore, radiation hygiene monitoring and control of radiation hazards play a key role in effectively reducing radiation doses for both medical workers and patients.
Below is an overview of commonly used medical X-ray imaging equipment in healthcare institutions:
1. CT Scanner (Computed Tomography)
CT is one of the most advanced modern imaging technologies. It works by detecting the varying absorption and transmission rates of X-rays through different tissues in the body. A highly sensitive system collects this data and transmits it to a computer, which processes the information to generate cross-sectional or 3D images of the scanned area.
- Advantages: High resolution and sensitivity, capable of detecting tiny lesions in any part of the body.
2. DR (Digital Radiography)
DR systems use electronic detectors to directly convert X-ray photons into digital images. The system typically includes a flat-panel detector, scanning controller, system controller, and image monitor.
- Advantages: Fast image acquisition, efficient workflow, and reduced radiation exposure.
3. Gastrointestinal X-ray System
This equipment is widely used for digestive tract examinations and various contrast imaging procedures, including esophagography, gastrointestinal studies, arthrography, myelography, cholangiography, bronchography, venography, urography, hysterosalpingography, and pediatric imaging. It can also assist in orthopedic procedures such as fracture reduction and foreign body removal under fluoroscopy.
- Applications: Covers diagnostic imaging for the digestive, skeletal, reproductive, and urinary systems.
4. Fluoroscopy Unit
Also known as a portable or fixed X-ray fluoroscopy machine, this device allows real-time imaging of internal body structures. The principle relies on the differential absorption of X-rays by various tissues—for example, bones absorb more radiation than muscles, resulting in different image intensities on the fluoroscopic screen or X-ray film.
- Applications: Commonly used in orthopedics and dentistry for dynamic imaging during diagnosis or minor procedures.
5. Mammography Unit
Also called a molybdenum-target X-ray machine, this device is designed specifically for breast imaging. It is an essential tool in gynecology and specialized clinics for the early detection of breast tumors and microcalcifications. It can also be used to image non-metallic foreign bodies or soft tissue masses like hemangiomas.
- Advantages: High-contrast, high-resolution images of breast tissue.
6. DSA (Digital Subtraction Angiography)
DSA uses digital image processing to subtract background tissues from X-ray images, leaving only the blood vessels visible.
- Applications: Provides detailed images of vascular structures, allowing for accurate assessment of vascular lesions, stenosis, and guiding interventional procedures.
7. Mobile X-ray Equipment
Mobile imaging devices are not fixed in one location and can be classified into mobile C-arms, mobile DR, mobile CR, and portable screen-film X-ray machines (less commonly used now).
- Applications: Suitable for radiology departments, ICUs, operating rooms, emergency rooms, and wards—ideal for imaging the head, chest, spine, abdomen, and limbs at the bedside.
8. Lithotripsy Machine (ESWL)
Extracorporeal Shock Wave Lithotripsy (ESWL) breaks down urinary stones using focused shock waves generated outside the body.
- Imaging Support: Typically used in conjunction with X-ray or fluoroscopy systems to accurately locate the stones prior to treatment.
9. Molecular Imaging Systems: SPECT/CT and PET/CT
SPECT (Single-Photon Emission Computed Tomography) and PET (Positron Emission Tomography) are nuclear medicine imaging technologies that visualize gamma rays emitted from within the body, also known as Emission Computed Tomography (ECT).
- Applications: When combined with CT, these systems enable precise localization and characterization of lesions, greatly improving diagnostic accuracy in oncology and neurology.
10. Dental X-ray Equipment
This includes intraoral X-ray machines, panoramic units, and dental CT systems—all essential tools in modern dental clinics.
- Applications: Used for detecting cavities, evaluating bone loss, and planning dental implants.
11. Linear Accelerator (LINAC)
These accelerators come in types such as electron, proton, and heavy ion, with electron LINACs being the most widely used in clinical settings. They generate X-rays or electron beams to precisely irradiate tumors inside the body.
- Applications: Effective for treating various types of cancer by shrinking or eliminating tumors.
12. Brachytherapy Machine
Brachytherapy is a form of internal radiation therapy that delivers radiation directly to the tumor site via radioactive sources.
- Applications: Widely used in the treatment of cervical cancer, prostate cancer, breast cancer, skin cancer, and many other localized tumors.
Conclusion
From basic digital radiography to advanced molecular imaging and radiotherapy systems, X-ray-based equipment plays a foundational role in modern medicine. Understanding the capabilities and applications of these tools not only helps patients make informed decisions but also underscores the importance of safety, precision, and innovation in radiological healthcare.
