Computed radiography

Computed Radiography (CR) is a digital imaging technology used in the field of radiography. It serves as a bridge between traditional X-ray film and modern Digital Radiography (DR) systems. CR uses phosphor imaging plates to capture images, which are then scanned and converted into digital form. This technology has revolutionized the way radiographic images are captured, processed, and stored, offering several advantages over traditional film-based radiography.

Overview

Computed Radiography works by using a special imaging plate that contains photostimulable phosphor. This plate is exposed to X-rays, which cause the phosphor to store the image. The imaging plate is then placed in a CR reader, where a laser scans the plate, stimulating the release of stored energy in the form of light. This light is captured and converted into an electrical signal, which is then digitized and processed to produce a digital radiographic image. The imaging plate can be erased and reused multiple times.

Advantages

• Digital Storage: CR images can be stored digitally, reducing the need for physical storage space and facilitating easy sharing and retrieval of images.
• Image Processing: Digital images can be enhanced and manipulated to improve diagnostic accuracy without the need for retakes.
• Dose Reduction: With proper optimization, CR can achieve diagnostic-quality images at lower doses compared to traditional film radiography.
• Environmental Impact: CR eliminates the need for chemical processing, reducing the environmental impact associated with film radiography.

Disadvantages

• Resolution: CR images may have slightly lower spatial resolution compared to DR systems.
• Workflow: The process of handling and scanning imaging plates can be more time-consuming than direct digital systems.
• Cost: Initial setup costs for CR systems can be high, although this is often offset by savings in film and processing chemicals.

Applications

Computed Radiography is used in various medical and industrial applications. In medicine, it is used for diagnostic imaging across multiple specialties, including orthopedics, chest radiology, and pediatric radiology. In the industrial sector, CR is used for non-destructive testing (NDT), inspecting materials and components without causing damage.

Comparison with Digital Radiography

While both CR and DR are digital imaging technologies, they differ in their image capture methods. DR captures images directly onto a digital detector, offering faster image acquisition and higher image quality. However, CR remains popular due to its flexibility in handling different sizes of imaging plates and its cost-effectiveness in certain settings.

Future of Computed Radiography

The use of Computed Radiography is gradually declining in favor of DR due to advancements in DR technology that offer higher efficiency and image quality. However, CR continues to be an important technology, particularly in settings where the cost of DR systems is prohibitive or where flexibility in imaging plate size is required.