Computerised Tomography (CT) or Computerised Axial Tomography (CAT)
Computerised Tomography (CT) or Computerised Axial Tomography (CAT)
Basics of CT or CAT
- Computerised Tomography, often referred to as CT, or Computerised Axial Tomography (CAT), is an advanced imaging technique used in the medical field to generate detailed images of the body’s internal structures.
- CT scans are carried out using a specialised machine that utilises a series of X-ray measurements taken from different angles to generate cross-sectional images of the body, termed ‘slices’.
- Unlike traditional X-rays that show bones and hard structures, a CT scan can visualise soft tissues as well.
How CT or CAT Works
- In a CT scan, an X-ray source and a detector rotate around the patient, who lies still on a motorised table.
- The X-ray beam passes through the body at varying levels of intensity, depending on the density and composition of the tissues involved.
- The detectors capture these variations, and the information is sent to a computer, which translates the data into an image.
- The collected data is processed to create two-dimensional cross sectional images or ‘slices’ of the scanned body part, which can then be compiled to create a three-dimensional image.
Clinical Applications of CT or CAT
- CT is primarily used in diagnosis of various conditions. It is particularly useful for visualising injuries to bones, internal organs, detecting cancers or visualising lung and heart conditions.
- CT scans are also essential for planning certain medical treatments involving precise organ locations such as radiation therapy for cancer treatment.
- Furthermore, CT scans can be used to monitor the progress of disease or effectiveness of treatments.
Advantages and Limitations of CT or CAT
- Advantages: A key advantage of CT scans includes their ability to produce highly detailed images of bones, blood vessels and soft tissues all together. Another major strength is their speedy capture time, which provides a quick diagnosis and aids in emergency decision-making.
- Limitations: CT scans do involve small doses of ionising radiation. Thus, they may not be suitable for certain individuals, such as pregnant women. CT scans are also more expensive than traditional X-rays and ultrasound imaging. The quality of the scan can also be affected by the patient’s body size or movement during the scan.
Comprehending the principles and practical applications of CT scans is vital for Medical Physics. Significant for both diagnosis and treatment, understanding CT scans is essential for healthcare professionals.