Tag: medical diagnostics

  • Ultrasound Scanning Techniques

    Introduction Imaging systems employ pulsed ultrasound or the pulsed Doppler mode. The instrumentation system consists of: The display can be in several different modes e.g. Generation and Detection of Ultrasound The physical mechanism normally used to generate and detect ultrasonic waves is the piezoelectric effect exhibited by certain crystalline materials which have the property to…

  • How Ultrasound Measurements are used in Medical Diagnosis

    Introduction The application of ultrasonic in medical field is based on sonar principle as used by bats, anglers with fish detectors, and ships at sea. This is a totally non-invasive procedure. Acoustic waves are easily transmitted in water and are reflected from an interface according to change in the acoustic impedance. All tissues of our…

  • Positron Emission Tomography (PET)

    PET scan is an imaging technique which produces images of the body by detecting radiation or gamma rays emitted from the body after the patient is injected with radioactive substance. When a positron emitted by a radioactive substance bombards an electron in the tissue, two gamma rays are emitted in the opposite directions as shown…

  • X-ray Imaging

    Background of X-ray Imaging X-rays were discovered accidentally by the Germany Physicist William Roentgen in 1895, while experimenting with electron beams in a gas discharge tube. He discovered that a screen in the laboratory started glowing when the electron tube was turned on, and continued to glow even after the tube was covered with a…

  • Introduction to Medical Diagnostic Techniques

    Diagnostic techniques are investigations and tests performed on patients with the intention to identify the cause of illness. The ultrasound is sonic energy at frequencies above the audible range. The most widely used applications of ultrasound in diagnostic medicine involve the non-invasive imaging of internal organs or structures of the body. Such imaging can provide…