AVH CT Scanner Reviewed By Experts

Excessive radiation doses from CT procedures has attracted widespread attention from the national media, and consequently, the general public. The AVH Imaging Services Department is committed to high-quality patient care, which includes producing images of the highest quality, while keeping the radiation dose to patients as low as possible. While CT accounts for 25% of the procedures in the Department, it is responsible for 75% of the dose to our patients. The dose from a chest CT is greater than the dose from a normal chest x-rays.

Recently, AVH engaged the services of Physics Consultants, Inc., (PCI), a Portland, Maine firm that specializes in radiation safety. They provide a service called CT DoseCheck, which is designed to optimize our CT doses. Dose optimization refers to the production of images that contain all the necessary information to make a diagnosis, while using the lowest dose possible. A team of medical physicists spent a day in the Imaging Services Department to assess the CT Imaging Section. They focused on several areas.

The first area observed was that of actual scan techniques. Many such techniques can be modified to reduce dose without affecting phantom image quality. PCI physicists used a test phantom to measure the doses and evaluate image quality for some common scans and then compared them with doses acceptable to the American College of Radiology (ACR). They scanned the test phantom repeatedly at lower doses to see how image quality was affected.

PCI representatives reviewed the Hospital’s already strong policies and procedures. Discussions helped improve our policy for shielding patients, which will lower doses even further!

In addition, PCI confirmed that the automatic dose reduction feature that is available on the AVH CT scanner is fully utilized. This feature obtains a “scout” image of the patient and then uses that image to change the technique factors in “real time” as the scanner is working. As the patient thickness decreases, the CT scanner lowers the dose. This is done because thinner body parts require less radiation.

AVH is pleased to share the results of this successful review by a team of experts, with the community that we are so fortunate to serve. We are also proud that the doses from representative scans from our machine are significantly below the maximum doses allowed by the ACR.

For more information about CT scans or the services provided by the AVH Imaging Services Department, please contact Wayne Couture, Imaging Services Director at 326-5725.