Radiology-Related Quality Programs and Organizations

Image Gently

Several studies have documented a rapid growth in computed tomography (CT) use in children since the advent of helical CT scanning, especially in the emergency department (ED) setting. From 1995 to 2008, there was a fivefold increase in CT exams in children visiting the ED. Over this time, the annual growth rate of CT use in pediatric ED visits was 13.2%. There are several reasons for this dramatic increase in CT in pediatric ED settings; most significantly, it paralleled technological advancements that allowed high-quality CT exams to be performed in a matter of seconds, which in turn usually obviated the need for sedation. Other proposed factors include the ability of CT to improve ED throughput, cost savings due to more accurate diagnoses, fear of malpractice, and repeat imaging due to breakdowns in communication.

The main concern over the increased use of CT in children is the risk of radiation-induced cancers. It is generally accepted that children are more susceptible to the effects of ionizing radiation from CT exams, due to a larger number of dividing cells and because they have more years of life for cancer induction to occur. A landmark paper by Brenner et al. in 2000 estimated that of 600,000 annual CT exams performed on children, an estimated 500 will ultimately die of radiation-induced cancer from the CT exam. A more recent study from the United Kingdom in 2012 estimated a 3.2 times greater risk of leukemia and a 2.8 times greater risk of brain cancer in children receiving effective doses currently in use.

In recognition of these trends and public health concerns, in 2006 the Society of Pediatric Radiologists (SPR) formed a committee to raise awareness within the medical community to the harmful effects of ionizing radiation exposure in children. In 2007, the SPR collaborated with the American College of Radiology (ACR), the American Society for Radiologic Technologists (ASRT), and the American Association of Physicists in Medicine (AAPM), to form the Alliance for Radiation Safety in Pediatric Imaging (ARSPI). The main purpose of the Alliance was to improve awareness in the imaging community and among pediatricians of the increasing use of CT in children and the potential harmful effects of ionizing radiation. The ultimate goal was to improve practice by reducing CT dose in children. One of the early actions of the campaign was to encourage imaging professionals to take a pledge to image gently. The pledge included the following:

• 1.

  Spreading the Image Gently message among staff

• 2.

  Evaluating protocols and making adjustments where appropriate to reduce dose

• 3.

  Respecting and listening to suggestions from every member of the imaging team

• 4.

  Communicating openly with parents

Much of the Alliance’s initial efforts went to educating imaging professionals in primarily adult hospital settings. In a 2008 article in the American Journal of Radiology (AJR), the core principles of the Image Gently campaign were outlined as follows:

• 1.

  Reduce or “child size” the radiation dose. The radiologist, technologist, and medical physicist should work together to adjust the kVp and mAs according to the size of the patient. Protocols for children are listed on the Image Gently website.

• 2.

  Scan only when necessary. For each proposed CT exam, the expected benefit of the exam must outweigh the risk of ionizing radiation exposure. This requires a discussion between the radiologist consultant and the referring physician.

• 3.

  Scan only the indicated region. Every attempt should be made to limit radiation exposure to the area of clinical concern. For example, if an incidental lung nodule is being monitored, it is unnecessary to scan the entire chest.

• 4.

  Scan once. Multiphase exams needlessly double or triple radiation dose and rarely provide more clinically relevant information.

Understandably, the first phase of the campaign focused on spreading their message to imaging professionals, including radiologists, technologists, and medical physicists. The next phase targeted referring physicians—pediatricians, emergency physicians, surgeons, and oncologists. Finally, the third phase focused on parents and the general public. The campaign effectively used social marketing to spread their message, including an Image Gently website, press releases, public service announcements, and healthcare blogs.

Studies performed more recently have suggested that CT use in children has stabilized or begun to decrease. A study in 2013 analyzing data from six major national health organizations showed stabilization followed by a slight decline in pediatric CT since 2007. The reasons for this trend are not entirely clear, but are likely due in part to efforts of the Image Gently campaign to raise awareness in the medical community to the harmful effects of ionizing radiation in children. However, the paper also made clear that there is still much room for improvement. For example, the authors estimated that applying the ALARA (as low as reasonably achievable) principles to reduce the highest 25% of doses to the median level would result in a 43% reduction in radiation-induced cancer in the future.

As of 2015, 91 organizations joined the Image Gently campaign and there have been more than 35,000 pledges. The Image Gently website serves as an excellent resource on radiation exposure from radiologic exams for imaging professionals, pediatricians, and parents. Although there is an emphasis on CT, radiation exposure from other radiologic exams, such as radiography, fluoroscopy, and nuclear medicine studies, is also addressed. The website also makes available appropriate CT protocols for children, a feature that several institutions have used. The protocols listed are a good starting point from which facilities may adjust techniques to further reduce dose while maintaining diagnostic quality.

Step Lightly

With the well-documented risk of malignancy for children exposed to increased radiation levels since the 1980s, the medical community has made great leaps in the effort to reduce the number of CT exams in children and to create pediatric protocols that reduce CT dose. Often overlooked, however, are other radiation-intensive exams and procedures. Encouraged by the success of the Image Gently campaign, in 2009 the Alliance for Radiation Safety in Pediatrics launched a similar initiative directed specifically at interventional radiology. This new program was titled Step Lightly, in reference to the idea that interventionalists should tread lightly on the foot-pedal by which images are obtained in the interventional suite.

A team of interventional radiologists, medical physicists, and radiation technologists developed a set of recommendations to inform the actions of the medical professionals ordering and performing interventional procedures. A checklist of important steps for reducing radiation dose to pediatric patients undergoing image-guided procedures now serves as a reminder to the treatment team, which is especially critical in facilities that are more accustomed to treating adult patients. The checklist highlights using alternatives to ionizing radiation such as ultrasound, and to use child-sized doses by adjusting acquisition parameters and collimating when using fluoroscopy. Advice and explanations for parents of patients are also provided via the Step Lightly section of the Image Gently website.

In the quest for achieving lower all-around radiation doses in children, certain steps are critical to the use of fluoroscopy. These are generally outlined in the checklist but should be addressed in depth for all interventional radiology staff at facilities that treat children. Some of the steps involve knowledge of equipment. There is a grid that is part of the fluoroscopy unit that reduces scatter and thereby sharpens the final image and increases contrast. Eliminating part of the beam, however, necessitates increasing the dose. Removing the grid results in a dose reduction of one-third to one-half, and there is now a wide consensus that grids should be removed for pediatric cases unless extenuating circumstances are present. In addition, newer fluoroscopy machines have the option to use pulse rather than continuous image acquisition. The x-ray tube emits pulses, lowering the dose in most cases by 25% to 28%. This can result in a choppy appearance when imaging a structure with rapid motion, such as the heart, but for most procedures the image quality is absolutely adequate and easily justified by the reduced levels of radiation. All members of the interventional radiology team should be aware of pulse fluoroscopy, and continuous fluoroscopy should be employed in the pediatric patient only under special circumstances. Finally, collimating the x-ray beam, as in adult fluoroscopy, limits patient and operator exposure by passing the beam only through the selected anatomic region.

Another factor in lowering the radiation dose to safer levels for children relates to operator technique. As indicated by the name Step Lightly, physicians and technicians should press on the fluoroscopy pedal only intermittently. Operators are reminded of this by placing an adhesive with the Step Lightly butterfly icon on the pedal itself. The last image saved should be used instead of obtaining a standard radiograph and can be used by the interventional radiology physician to take stock of the relevant anatomy with the x-ray beam off. Collimation, itself an essential dose reduction technique, should be performed with the beam off. This avoids obtaining unnecessary images while the collimator blades move into place. Many modern units have electronic collimation, whereby the operator can view the blades moving in or out on a last image save, instead of a live image. Operators must also keep in mind that both geometric and electronic magnification increases patient radiation dose and should be used sparingly in the pediatric population.

A final method of reducing ionizing radiation when a pediatric patient is on the fluoroscopy table is by adjusting patient positioning. Having the patient as close as possible to the image intensifier and as far away from the x-ray tube as possible minimizes radiation exposure and also minimizes image blurring. In the pediatric population it is also necessary to consider the vulnerability of developing organ systems. The male and female reproductive organs should be covered with lead shields at all times during fluoroscopy unless imaging these structures is essential for the procedure. In instances where a particular body part must be under fluoroscopy for an extended time period, rotating the patient or the c-arm of the fluoroscopy unit can achieve dose spreading, or distribution of the dose over a larger region of the patient’s skin, with a less concentrated dose to any one area.

Following a procedure, the dose administered to the pediatric patient should be reviewed and recorded. Reviewing the dose creates increased awareness among the members of the treatment team of how much exposure patients are receiving and can alert them to potential problem areas in complying with their checklist. Recording the dose helps the patient’s family and the medical community keep track of how much radiation the patient is receiving over time, which can influence future decisions about imaging and procedures. Using these methods, the interventional radiologist and technologist play a major role in reducing the risk of malignancy and other negative sequelae of radiation in child patients.