FDP X-Ray principle and parts in radiology.pptx

X Ray principle and parts

1. INTRODUCTION TO RADIOGRAPHY X-RAY KEREN EVANGELINE. I ASSISTANT PROFESSOR (O.G) DEPARTMENT OF MEDICAL ELECTRONICS

2. X- RAY GENERATION METHODS Bremsstrahlung Radiation technique – Produces X-Rays in continuous spectrum with different wavelengths and frequencies. Characteristic X-Rays - Have discrete energies corresponding to the differences in energy levels between electron shells in the target material.

3. X- RAY TUBE Made of thin Pyrex glass or metal enclosure to withstand high heat load and minimize x-ray absorption Gas is evacuated So that the electrons wont collide with the air molecules in the tube The X-ray tube is the single most important component of the radiographic system. It is the part that produces the X-rays.

4. COLLIMATOR In order to increase the image contrast and to reduce the dose to the patient, the X-ray beam must be limited to the area of interest. Two types of devices are used for this purpose, viz. collimators and grids. The collimator is placed between the X-ray tube and the patient (Fig. 19.14). It consists of a sheet of lead with a circular or rectangular hole of suitable size. Alternatively, it may consist of four adjustable lead strips which can be moved relative to each other.

5. BUCKY GRID Grids are inserted between the patient and the film cassette (Fig. 19.15) in order to reduce the loss of contrast due to scattered radiation. A grid consists of thin lead strips separated by spacers of a low attenuation material. The lead strips are so designed that the primary radiation from the X-ray focus, which carries the information, can pass between them while the scattered radiation from the object is largely attenuated. Because of the shadow cast by the lead strips, the final image is striped. These grid lines do not usually interfere with the interpretation of the image. However, final details in the image may be concealed. In order to avoid this, the grid can be displaced during the exposure so that the lead strips are not reproduced in the image. Such moving grids are known as ‘Bucky Grids’.

6. AEC is a feature commonly found in modern X-ray systems and radiography equipment. It automatically adjusts the exposure parameters (such as exposure time, tube current, or tube voltage) based on the detected radiation reaching the X-ray detector. The primary purpose of AEC is to optimize image quality while minimizing unnecessary radiation exposure to the patient. AUTOMATIC EXPOSURE CONTROL (AEC)

7. MANUAL CONTROLS