The discovery of the X-ray
Roentgen (RR) 1895 X-ray production The X-rays are produced when fast moving electrons with sufficient energy strike a target. Most of the electron energy is converted to heat but a very minute amount (less than 1%) is converted to x-ray .History of the X- ray tubesThe primitive X – ray tube.Rotating anode tube.Modern tube with collimation.
The first X-ray image
The X-ray properties in diagnostic Radiology are depend on: 1-Ability to penetrate organic matter 2- Ability to produce photographic effect on (photo sensitive film) 3- Ability to produce phosphorescence( fluorescence) in certain crystalline materials ( intensifying screen)TISSUES PENETRTABILITY
Depend on: 1- Tissue density 2- Atomic number of tissue Classified as: A- Radiolucent materials through which the x-rays passed readily. B- Radio-opaque materials in which x-rays are absorbed to considerable degree in their passage.Very radiolucent : Gases Moderately radiolucent : Fatty tissues Intermediate : Connective tissue Muscles Blood Cartilages Moderately radio-opaque: Bones Calcium salts Very radio-opaque: Heavy metals
Radiation effects (Hazards)
1- Acute effects: acute illness & skin erythema 2- Chronic effects: a-Blood forming organs ( Leukemia & a granulocytosis) b-Induction of malignant tumors( skin T.) c-Eye lens (cataract) d-Ovaries & testicles ( Infertility) e-Genetic changes. f- Reduction of life span.Protection
The patients. The employer.Definition of terms
Radio-opacity (Radio-opaque) Depend on x-ray absorption by tissues ( bones , stones , abnormal pathology and heavy metals )Radio-lucency (radio-lucent)
Low tissue absorption ( gases , stones , pathology)
Consolidation ( solid lung)Replacement of air in the alveoli by fluid Change of radio-lucency to radio-opacity The fluid may be: Exudates as in pneumonia Pus as in pneumonia Serous as in oedema Blood as in heamatoma Cells as in tumor
Cavity
A hole in the lung with thin wall -- Tb.If there is fluid ( fluid level ) -- Abscess
OsteopeniaDecreased bony density , result in thin cortex and wide medulla Osteoporosis & osteomalacia
Osteolytic (bone destruction)
Single , multiple or diffuseOsteoblastic : means increase bone density
It is either Localized Multiple DiffusePeriosteal reaction: New bone formation arising from periosteum following bone destruction.
TYPES: Linear e.g. Osteomyelitis Lamellated (Onion peal) e.g. Ewing sarcoma. Perpendicular (sun ray ) e.g. Osteogenic sarcoma
Filling defect It is either:
Bad preparation
S.O.LAir Fluid level: sharp line of demarcation between air translucency and fluid.
In the bowel can be caused by Intestinal obstructions. In a cavity as in Abscesses. In the pleural cavity as in Hydro-pneumo –thorax.Types of X-rays imaging: Plain Film Contrast film Contrast is a chemical material of high atomic number used to visualize the lumen of G.I.T. , U.T , VESSELS . etc. Examples: G.I.T----Gastrografin , Ba sulfate Bronchial system –Dionosil I.V. contrast ( organic iodides)Hypaque Conray Urografine