Introduction to Radiography

Introduction to Radiography

• Radiography is a medical imaging technique using ionizing radiation to create images of internal body structures.
• X-rays are ionizing radiation that penetrate and interact with body tissues.
• Tissue density and composition affect x-ray absorption.
• The recorded image shows varying absorption as differences in darkness or shade, revealing anatomical structures.

Types of Radiographic Images

• Conventional radiography creates two-dimensional images using X-rays.
• Digital radiography (DR) converts x-ray signals to digital data, improving image quality and storage.
• Fluoroscopy provides dynamic, moving images of internal structures, like swallowing or contrast medium flow.

Basic Principles

• X-rays are high-energy electromagnetic waves.
• Denser tissues (e.g., bone) absorb more X-rays, appearing brighter on the image.
• Less dense tissues (e.g., air, fat) absorb fewer X-rays, appearing darker.
• Contrast agents enhance the visibility of specific structures.

Radiographic Techniques

• Proper patient positioning is critical for clear images.
• Standard projections and views visualize relevant anatomical structures.
• Collimation reduces scatter radiation, improving image quality.
• Intensifying screens and imaging plates capture the x-ray image.

Applications of Radiography

• Radiography identifies fractures, infections, and tumors.
• It assesses bone density for osteoporosis.
• It visualizes foreign objects.
• It's used in TB screening, along with other techniques.
• It screens for various conditions, like chest diseases.
• It aids in cardiovascular imaging and related pathology analysis.

Safety Precautions in Radiography

• Radiation exposure is a concern, requiring shielding and protective measures.
• Personnel use protective gear to minimize radiation exposure.
• Time, distance, and shielding (the cardinal principles) are crucial for minimizing exposure.

Digital Radiography (DR)

• DR uses a flat panel detector to convert x-rays to digital signals.
• This technology enables faster image acquisition and processing, making images readily available.
• Images are easily manipulated for better viewing and diagnosis.
• DR reduces patient exposure compared to conventional methods.
• Digital images offer enhanced storage and retrieval compared to film.
• Digital images enable quantitative analysis with advanced tools.

Contrast Agents

• Contrast agents highlight specific structures or organs in a study.
• Contrast agents vary in density, viscosity, and chemical composition.
• Contrast delivery methods depend on the imaging technique.