Medical Uses of Radiography
– Radiography is used for diagnostic purposes in medical imaging.
– Different modalities of medical radiography produce various types of images, each with a different clinical application.
– Radiographic anatomy is the discipline that involves studying anatomy through radiographic images.
– Projectional radiography involves exposing an object to X-rays or other high-energy radiation and capturing the resulting shadow as a latent image.
– Computed tomography (CT) uses ionizing radiation and a computer to create images of both soft and hard tissues.
– Dual energy X-ray absorptiometry (DEXA) is primarily used for osteoporosis tests.
– Fluoroscopy provides moving projection radiographs.
Industrial Radiography
– Industrial radiography is a method of non-destructive testing that verifies the internal structure and integrity of components.
– It utilizes X-rays or gamma rays, which are electromagnetic radiation with the shortest wavelength.
– Industrial radiography can penetrate and travel through various materials.
Image Quality and Radiation Dose
– Image quality in radiography is dependent on resolution (ability to show closely spaced structures) and density (blackening power of the image).
– The size of the X-ray source affects sharpness in radiographic images.
– Different procedures have varying radiation doses, with a chest X-ray having a dose of 0.1mSv and an abdominal CT having a dose of 10mSv.
– Safety standards ensure low radiation dosage in radiography.
Shielding and Campaigns
– Lead is the most common shield against X-rays due to its high density and stopping power.
– The thickness of shielding affects exponential attenuation, and doubling the thickness squares the shielding effect.
– Image Gently campaign focuses on maintaining high-quality imaging with low doses for pediatric patients.
– Image Wisely campaign focuses on the adult population and is endorsed by various professional medical organizations.
– The World Health Organization and IAEA are working on best practices for radiation safety.
Equipment and Dual-energy Radiography
– X-ray generators, betatrons, linear accelerators, and synchrotrons are used in radiography and computed tomography.
– Gamma rays use radioactive sources in radiography.
– Vacuum tubes with wide input surfaces coated with caesium iodide (CsI) are used in radiography devices.
– Dual-energy radiography involves acquiring images using two separate tube voltages.
– The history of radiography includes the discovery of X-rays by Wilhelm Conrad Röntgen and their use in World War I to treat wounded soldiers.https://en.wikipedia.org/wiki/Radiography