The New Wave of Imaging

Radiation Dose Optimization

In recent years, medical imaging manufacturers have introduced new products, system innovations and patient care initiatives that optimize radiation dose. Thanks to these innovations, physicians are able to better diagnose disease and stage treatment options.

Examples

Computed Tomography (CT)

Iterative reconstruction technologies allow clinicians to reduce dose while preserving image quality and anatomical detail. Today, iterative reconstruction products deliver previously unattainable levels of combined noise reduction, resolution gain, improved contrast and artifact suppression (i.e. eliminating streaks). This innovative new technology can be used for all patients, but is particularly useful in reducing dose for women of child-bearing age, pediatric patients, and patients who require regular follow-up scans to monitor their treatment.

 Manufacturers are increasingly incorporating a variety of dose reduction programs and technologies in all computed tomography (CT) equipment and partnering with hospitals to identify ways for clinical staff to obtain the necessary CT images with significantly lower dose. New advanced adaptive image filters identify image features and make processing adjustments to reduce dose while maintaining diagnostic image quality. In cardiac imaging, these filters have been shown to help clinicians reduce dose while maintaining coronary anatomy for a broad range of patient sizes. Advanced Automatic Exposure Control (AEC) such as real-time 3D dose modulation helps deliver consistent image quality by automatically accounting for the changing dimensions of the patient – thereby personalizing each scan. Finally, dynamic Z-axis tracking reduces unnecessary dose in helical scanning by providing automatic, continuous correction of the X-ray beam position to block unused radiation at the beginning and end of a scan.

 In cardiac CT imaging, the X-ray is typically active for the entire duration of a scan. New interventional cardiology products reduce the patient’s exposure to radiation through prospective triggered gating, which means the X-ray is on only during critical phases of the cardiac cycle. This technology has been shown to reduce a patient’s X-ray exposure time by up to 70 percent. New technologies minimize radiation for complex neuro perfusion CT exams – for example, related to stroke or tumor analysis – by allowing physicians to see more anatomy in a single scan with just one contrast injection. The latest imaging advances for patients with arrhythmia detection (irregular heartbeats) during coronary computed tomography angiogram (CTA) exams have significantly lowered patient dose. By using a helical acquisition technique to provide one continuous image instead of multiple images, the software can automatically detect and adjust to a patient with irregular heartbeats, providing more conclusive exam results.

 CT Dose Check enabled protocols notify and alert CT operators when scan settings are likely to exceed pre-assigned dose thresholds, so necessary adjustments can be made to avoid unnecessary radiation prior to the exam.

Interventional X-Ray

Radiation dose displays and threshold alerts increase awareness of the radiation exposure being administered. The latest advance in dose management technology for lengthy interventional procedures is the ability to track X-ray skin dose exposure in real time through an intuitive, color-coded indicator on a 3D visual representation of the patient. This allows the clinician to make adjustments throughout the procedure and minimize the risk of locally concentrated high exposure to radiation dose.

 The NEMA XR 24-2008 standard, Primary User Controls for Interventional Angiography X-Ray Equipment, provides a standardization of user controls to ensure that interventional X-ray equipment is used consistently for all manufacturers and across different healthcare settings. This helps to increase familiarity and efficiency when clinicians are moving from one room to another, ultimately facilitating dose reduction.

 Flat-panel digital detectors improve dose efficiencies in modern systems in conjunction with advanced image processing, resulting in lower dose for both patient and operators. In chest imaging, flat-panel detectors have been shown to yield improved image quality with a significant reduction in radiation dose.

 Innovations in dose reduction technology for interventional X-ray enable greater precision during a procedure, thereby minimizing unnecessary exposure to radiation. Various dose modes and frame rates can be selected to allow for appropriate dose utilization and optimization throughout an interventional procedure. Programmable collimation limits exposure to just the desired area under study, minimizing the radiation delivered to surrounding tissues. Improvements in c-arm flexibility allow for improved placement and procedural efficiencies, shortening the procedure time and reducing dose to both operators and patients. Finally, programmable spectral filtration facilitates accurate delivery of the proper radiation beam for a specific procedure.

 Spot fluoroscopy is a more precise imaging technique than conventional collimation. It allows operators to observe a region of interest using live fluoroscopy while simultaneously viewing the surrounding anatomy, lowering dose and providing a more complete image for faster diagnoses.

Pediatric Imaging

Many techniques can be used to dramatically reduce radiation exposure in children, while still enabling high-quality diagnostic images. Pre-loaded pediatric protocol selection tools facilitate pediatric emergency care and reduce medical errors by helping clinicians determine appropriate dose levels and utilize appropriately-sized equipment and techniques for pediatric patients. Removable grids can reduce the amount of radiation administered to pediatric patients during interventional X-ray procedures. Additionally, specially designed child-friendly equipment helps put the patient at ease, eliminating the need to use sedation or perform additional imaging to obtain the desired image.

MITA champions the ALARA principle, which stands for “as low as reasonably achievable.”

Manufacturers have introduced new products, system innovations and patient care initiatives that optimize radiation dose without compromising image quality.

MITA leads the development of industry and international standards for imaging systems.