Medical physics is a branch of physics that deals the applications of principles of physics to medical diagnosing and treating abnormal tissues.

Medical imaging refers to several different technologies that are used to view the human body in order to diagnose, monitor, or treat medical conditions.

There are several imaging techniques that can provide imaging of biological samples.


MRI scan

Radiography 

CT scan

 

X-ray

  Electromagnetic (optical)

Ultrasound

X-Ray computerized tomography (CT) scan

An X-ray imaging is based on the absorption of X-rays as they pass through the different parts of a patient’s body. 


Differences in the densities of body tissue allow us to see inside the body by creating a shadow gram.

Magnetic resonance imaging (MRI) 

MRI is used to absorption or emission of electromagnetic radiation by electrons and atomic nuclei in response to the application of certain magnetic fields.

Stethoscope and Ultrasound


Stethoscope is the most familiar clinical use of sound is in the analysis of body sounds.

Stethoscope

This instrument consists of a small bell-shaped cavity attached to a hollow flexible tube. 

The bell is placed on the skin over the source of the body sound (such as the heart, intestines, or lungs). 

The sound is then conducted by the pipe to the ears of the examiner who evaluates the functioning  of the organ.

A stethoscope can detect sound waves with frequency ranging from tens to thousands of Hertz

Ultrasound


Ultrasound

A procedure that uses high-energy sound waves to look at tissues and organs inside the body. The sound waves make echoes that form pictures of the tissues and organs on a computer screen (sonogram).

Ultrasound

If the frequency of sound is higher than 20 KHz (0.02MHz), it is called ultrasonic or ultrasound. 

Typical frequencies used in medical ultrasound are 3.5-10 MHz.

Ultrasonic waves penetrate tissue and are reflected, scattered and absorbed within it. 

The scattered and reflected ultrasound contains information about the form and structure of the tissue.

Radiation therapy

Radiation therapy, also called radiotherapy, is a type of cancer treatment. This treatment uses beams of intense energy to kill cancer cells.


The photons of X-rays and gamma-rays and the particles emitted by radioactive nuclei all have energies far greater than the energies that bind  electrons to atoms and molecules.

In controlled doses radiation can be used therapeutically. In the treatment of certain types of cancer. 

By careful placement of the radioactive material and by controlling the dose, the cancer cell can be destroyed without greatly damaging the healthy tissue.

Last modified: Wiixata, 26 Caamsa 2025, 8:57 AM