At the recent International Society for Computed Tomography (ISCT) annual meeting, held in San Francisco, Dr. Eliot Siegel, from the University of Maryland, discussed an evolving technique for CT dose-reduction. This application does not focus on simulated image noise as a measure of image quality, but instead, works to more accurately depict that noise in low-dose CT scans. In other words, this technique aims to optimize dose based on what the radiologist needs to see.
According to the presentation, the future of low- dose optimization will rely on a combination of the visual perception system and sophisticated mathematical models designed to minimize the dose for every imaging exam without impairing the quality of the image to the radiologist. In fact, the current methods for low-dose optimization are already on the way out as awareness for radiation dose continues to evolve.
Dr. Siegel’s analysis of noise in the new world of iterative reconstruction is very sophisticated and thoughtful. Concepts of pink and white noise plus just-noticeable differences really are cutting edge. These ideas will clearly advance our understanding of how to get a world of fully automated dose minimization.
Dr. Siegel and his team of researches, as usual, are thinking profoundly and in very innovative ways. These concepts certainly raise great hope for a much more systematic future combined with much more sophisticated math to make patient doses even lower than we had previously dreamed! It will be an exciting next three years for dose reduction techniques and technology!
The Choosing Wisely Campaign is a recent initiative of the ABIM Foundation to encourage physicians and patients to take a second look at tests and procedures that may be unnecessary… and potentially, harmful. The American College of Radiology was one of nine US specialty societies that developed lists of the Five Things Physicians and Patients Should Question.
See the ACR’s outlined recommendations of the procedures that should be utilized less in radiology practices:
• Imaging for uncomplicated headache, absent specific risk factors for structural disease or injury.
• Imaging for suspected pulmonary embolism (PE) without moderate or high pretest probability of PE.
• Preoperative chest x-rays without specific reasons due to patient history or physical exam.
• CT to evaluate suspected appendicitis in children until ultrasound is considered an option.
• Follow-up imaging for adnexal (reproductive tract) cysts 5 cm or less in diameter in reproductive-age women.
All five of these recommendations are ones that I would certainly agree with. In fact, I wouldstrongly emphasize that CT for possible pulmonary embolism in young women be avoided unless there are clinical criteria which raise suspicion to at least moderate level. Additionally, ultrasound is a great modality to check for appendicitis in children, especially those that are young and/ or thin.
For the full recommendations by the ACR, please see here. Remember, informed patients are an integral part of the Choosing Wisely campaign.