1. X-RAY MEASUREMENT AND DOSIMETRY Salman Albeshan

2. EXPOSURE 2 It is the quantity that expresses the concentration of radiation delivered to a specific point. Old unit: ROENTGEN(R). SI unit: COULOMB/Kg of air. 1R=2.58x10(-4) 1C/Kg=3876R

3. ABSORBED DOSE. It is the quantity that expresses the concentration of radiation energy at a specific point within the body tissue..OLD UNIT : RAD.SI UNIT : GRAY 1Gy=100Rad 1Rad=1/100Gy 3

4. SEVER. This is the unit used only in radiation protection and it is equal to gray multiply By quality factor (for x-ray=1) 1SEVER=100REM 4 INTEGRAL DOSE.It is the total amount of energy absorbed in the body..UNIT:GRAM –RAD.

5. EXPOSUR FACTORS 1.Kilo-voltage. 2.Milliamperes. 3.Secoeds. 4.FFD. 5.Focal spot size. 6.Type of film. 7.Grid. 5

6. KILO-VOLTAG.The technicians have four matter in mind before selecting the KVp value: *Penetration,image contrast, image un-sharpness and radiation protection. 6 MILLIAMPERE-SECOND (MAS).It control the image density.

7. FOCUS FILM DISTANCE(FFD).The FFD used for most of examination is approximatly100cm..Short distance increase the intensity..In the lateral projection of cervical spine and chest the FFD is 180cm. 7

8. GRID. It is a device, which is used to enhance the image contrast by Removing the scatter. Is made up of lead strips and It is Placed between the patient and image receptor. *Types of grid: 1.Linear. 2.Parallel. 3.Focused. 4.Cross. 5.Moving. 8

9. Conventional X-ray Imaging. X-ray Production. Electrons from cathode filament are accelerated towards and impact the rotating anode. Rapid deceleration produces heat (~ 99%) and x-rays (~1%) High Electrical Potential Electrons - + Exposure Recording Device Radiation Penetrate the Sample