July-August 2019

Radiation Reduction Risk in Children and Adults

Erin Simon Schwartz, MD

Erin Simon Schwartz

Radiation risks have received a large amount of attention in the lay press, some of it actually warranted, while other concerns have been quite overblown. The most recent, available review of data provides support for the linear nonthreshold model of carcinogenic effects of radiation; however, the “risks from a few tens of mGy are uncertain and are predicted to be very small.”1 The noncarcinogenic effects, most commonly cardiovascular, are less well substantiated. All practicing radiologists should be familiar with the ALARA (as low as reasonably achievable) practice, and to date there have been over 100,000 pledges to Image Gently and Image Wisely, which are pediatric and adult initiatives to reduce radiation exposure, respectively. Step Lightly, the program to reduce radiation dose during fluoroscopic and angiographic procedures, may be less familiar to some. I urge every reader to familiarize themself with the materials available from these programs, as well as to incorporate the strategies outlined in the following papers.

In the first paper featured in this edition of the AJNR News Digest, Sadigh and colleagues utilized the CT Dose Index Registry of the American College of Radiology to determine the variation in head CT doses for pediatric patients throughout the United States. Their analyses revealed “considerable” variation; however, the volume CT dose indices were consistently lower at children’s hospitals and Level I trauma centers than in academic centers, nontrauma centers, and community hospitals. The authors encourage dedicated pediatric teams to create pediatric CT protocols that optimize the balance between minimizing radiation dose and preserving diagnostic image quality, in line with the recommendations from the Image Gently Alliance.

Similarly, in the pediatric neck, the goal is always to reduce radiation dose while maintaining high image quality. Tipnis and colleagues assessed image quality in a population of children undergoing clinical neck CT prior to, and following, the implementation of a “low-dose” protocol. While the image quality in the low-dose studies was slightly lower in … more »


Noncontrast Head CT in Children: National Variation in Radiation Dose Indices in the United States

Gelareh Sadigh


Kimberly Applegate

Approximately 6% of CT scans performed in the United States are performed on children, accounting for about 75% of the radiation dose in children, with the head being the most frequently imaged pediatric body part.

Many attempts have been made to quantify risks associated with ionizing radiation use in medical imaging, with some studies suggesting that radiation dose from pediatric head CT scans may increase the risk of developing leukemia or other solid tumors, while others suggest radiation dose to the lens of the eye from head and neck CT scans may increase the risk of developing cataracts. Children are more radiosensitive than adults and have a longer … more »


Radiation Dose and Image Quality in Pediatric Neck CT

Tipnis Sameer


Maria Vittoria Spampinato

Pediatric CT poses unique challenges in terms of achieving diagnostic-quality images using the least amount of radiation. Our purpose for this project was to implement standardized pediatric CT protocols, which yield high-quality diagnostic images at the lowest patient dose across different scanners at our institution. Another objective of this quality improvement project was to teach our trainees the basics of how to improve safe and effective imaging in pediatric CT.

When we evaluated our “baseline” protocols, we found that neuroradiologists at our institution deemed the image quality of neck CT studies across a wide range of CT dose levels and techniques to be diagnostically acceptable. In light … more »


Reduced Patient Radiation Exposure during Neurodiagnostic and Interventional X-Ray Angiography with a New Imaging Platform

Ajay K. Wakhloo


Ajit Puri

Advancements in x-ray imaging for neurointerventional procedures aim at dose reduction to patients, physicians, nurses, and x-ray technologists without compromising image quality and workflow. Beyond unknown side effects, the most important radiation-induced damages following the treatment of complex spinal and cerebrovascular disorders include erythema, epilation, and skin necrosis.

To tackle this matter, a new angiographic imaging platform (AlluraClarity, Philips Healthcare) has been developed that utilizes a dose-reduction technology, which applies to digital fluoroscopy and DSA. In short, the system uses a real-time image processing chain, which combines image noise reduction, motion correction, and contrast-dependent temporal averaging, all of which result in enhanced image quality and allow a … more »

Patient Safety

Radiation Dose Reduction in CT-Guided Spine Biopsies Does Not Reduce Diagnostic Yield

Amish Doshi

At our institution, we perform a variety of image-guided procedures, many of which are spine biopsies. In our practice, CT is often the preferred modality for guidance for these types of procedures. As a result, imaging parameters and radiation dose become important considerations. In an attempt to limit the radiation dose to patients undergoing these procedures, we set out to determine if a modified, low-dose protocol for CT-guided spine biopsies would provide a similar yield to our routine imaging. We found no significant difference in the diagnostic yield between biopsies performed at a lower CT dose and those performed at a standard CT dose. Given the importance of limiting the radiation dose to patients, and the … more »