Sometimes, making an exact diagnosis can be challenging for doctors. Medical imaging has made this challenge far easier.
Medical imaging plays an important role in modern medicine. It is the process of creating images of the inside of the human body to diagnose medical problems and aid in the treatment process.
- screen for possible health conditions before symptoms appear
- diagnose the likely cause of existing symptoms
- monitor health conditions that have been diagnosed
There are many types of medical imaging. The main types of imaging used in modern medicine are radiography, ultrasound (USG),?computed tomography (CT) scans,?magnetic resonance imaging (MRI), Positron Emission Tomography (PET) scan and mammography.?Each imaging type uses a different technology to create an image.??
- X-rays are a type of electromagnetic radiation. The test works by firing X-rays at a part of your body & using a film to capture the X-rays that pass through your tissues. The denser areas like the bones absorb more X-rays and appear lighter (white) in the image. It is used widely for orthopaedic issues & lung diseases.?
- Ultrasound is non-invasive, non-radioactive in nature. Ultrasound probes use high-frequency sound waves. The reflected waves are captured by a computer, creating an image. Ultrasounds can be used to image the eyes, muscles, abdominal organs, heart & in orthopaedics to investigate rotator cuff injuries. Ultrasound shows processes in real-time, which is why it is useful for immediate assessment of certain structures.?
- A CT scan combines a series of X-rays taken from different angles. CT scans produce much more detailed images than regular X-Rays & can actually take an image of internal organs. CT scans are typically used for complicated or unusual fractures. It is also used to detect tumours & monitor the progression of conditions like heart disease, emphysema, any growths, etc. The advantage of CT over X-ray is that it enables a three-dimensional insight into the body, giving a more accurate presentation of the area of interest. A?CT scan can also be used in patients with metallic implants or pacemakers, for whom MRI is contraindicated.?
- MRI involves radio waves & magnetic fields to look at the organs & other structures in the body. The MRI scanner is a large tube that contains a massive circular magnet. This creates a powerful magnetic field. MRI is used to diagnose aneurysms, multiple sclerosis, stroke, spinal cord disorders, tumours, blood vessel issues, and joint or tendon issues. It is mostly used for neuroimaging. MRI is contraindicated for people with metal implants, due to the intense magnetic field it creates. Compared to CT, MRI provides better contrast in images of soft tissues, e.g. in the?brain?or abdomen.?
- PET uses a radioactive substance, called a tracer & a scanner to examine how your tissues or organs are functioning. The tracer is injected into the patient's vein. The scanner detects radioactive signals emitted by the tracer and converts these signals into a 3D image. The tracer will be absorbed by different parts of the body in varying amounts and this allows doctors to see which areas show abnormal metabolic activity. It also helps to find the location of a tumour or spot other areas where the cancer may have spread.?
- A mammogram is an X-ray image of the breast tissue & is beneficial in early screening & detection of breast cancer.
