How much radiation do medical imaging tests deliver to a patient? How much and what kind of risk is involved with imaging radiation? These and other questions are on the minds of patients who receive recommendations for such imaging tests from their doctors.

Decisions concerning diagnostic testing are best made after all of the costs and benefits are discussed and weighed, says the American Heart Association, or AHA, in a new statement published this week in the journal Circuation. The AHA and several other organizations, including the American College of Cardiology, endorse the recommendation that doctors should discuss the risks associated with ionizing radiation before an imaging test is conducted.

Tests that deliver ionizing radiation to the patient include X-rays, cardiac stress tests, CT scans, and certain heart procedures. The main concern is that ionizing radiation exposure can potentially increase an individual’s lifetime risk for developing cancer.

“There is continuing concern on the part of patients in the area of ionizing radiation,” said Dr. Andrew J. Einstein, an associate professor of medicine in radiology at Columbia University in New York and co-author of the statement.

The risks associated with individual imaging procedures is quite small, and the clinical benefit conferred by the insights from such tests is often tremendous and outweigh the costs. However, patients still often have questions related to the radiation.

“The purpose of this document is to address physicians in particular and provide recommendations in terms of methods that can enhance safety and methods that can enhance patient understanding,” Einstein told Reuters Health during a telephone interview.
The statement asserts that the decision to proceed with imaging involving ionizing radiation exposure should be shared by both the doctor and the patient. The responsibility of educating and informing the patient, the statement declares, rests squarely on the doctor.

“As doctors, it is our obligation to make sure that we, our colleagues and our patients understand the potential benefits of a medical imaging study as well as potential risks,” said Einstein. “Patients shouldn’t be scared off by a one in X chance of developing cancer, they should be reassured by the benefits of the imaging.”