UCLA Campus    |   UCLA Health    |   School of Medicine Translate:
UCLA Health It Begins With U

Physicians Update


Physicians Update

Fall 2009

Protocols for Pediatric Radiology: Children Are Not Small Adults


Pediatric RadiologyDramatic advances in imaging technologies are improving the ability of pediatric radiologists to diagnose complex cases in children.

“Where we once had a very limited arsenal of imaging tools, such as plain films and fluoroscopy, we now have an enormous variety, including ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET),” says M. Ines Boechat, M.D., chief of pediatric imaging at Mattel Children’s Hospital UCLA. However, physicians must also be alert to potential harm to youngsters from the powerful instruments. “What is good for an adult patient may not be good for the pediatric patient,” Dr. Boechat says.

Of particular concern is the significant rise in the use of CT scans in children. The Society for Pediatric Radiology, of which Dr. Boechat is past president and current chair of the board of directors, estimates that 7 million CT studies are performed on children every year in the United States, and that use is increasing at a rate of 10 percent per year. Although these tests can be lifesaving, they may expose children to unnecessarily high levels of radiation, particularly when the techniques are not tailored to children’s smaller bodies.

“One of the concerns is that many centers that have both adult and pediatric cases may be using adult doses for pediatric patients and exposing them to more radiation than is necessary,” Dr. Boechat explains. Because they are growing and their cells are dividing rapidly, children are believed to be more sensitive to radiation’s effects than adults, she notes. The American College of Radiology has released new guidelines on the subject, and the Alliance for Radiation Safety in Pediatric Imaging, a consortium of professional societies concerned about the issue, has launched the Image Gently campaign to promote safe practices; UCLA is an active participant in the campaign.

Wherever possible, pediatric radiologists are looking to US and MRI — noninvasive imaging modalities that don’t emit radiation. MRI, in particular, has gained favor as increasingly powerful machines provide clearer pictures of patient anatomy, tissue characterization and functional data with no radiation exposure. Pediatric radiologists now have access at UCLA to an MRI scanner with a 3-Tesla magnet, which provides twice the field strength of conventional 1.5-Tesla scanners and exquisite anatomic detail in shorter scanning times. “MRI has become a very powerful modality for children,” says John Paul Finn, M.D., director of magnetic resonance research at UCLA. “With the 3-T MRI, we are getting more detailed information about all kinds of abnormalities in children as young as 1 day old.”

The more advanced MRI techniques have been particularly valuable for children with complex congenital heart disease, Dr. Finn says, by showing cardiac structure and function, as well as details of the vascular anatomy, in unprecedented ways. MRI is also playing a growing role in children who are candidates for organ transplantation and for patients with inflammatory bowel disease, and MRI has been extensively used in neural and musculoskeletal imaging.

Imaging TechnologiesMost MRI scans demand that the patient lie perfectly still. For young children, this typically requires sedation, making it important that these patients go to a center in which pediatric sedation is well established and safe. At UCLA, various levels of required sedation are administered by ICU nurses under the supervision of a pediatric anesthesiologist, or, if needed, general anesthesia is given by the specialist.

“MRI is much more overhead-intensive when it involves younger children,” Dr. Finn says. “The machines have to be capable of interfacing with the anesthesia equipment, and the anesthesiologist needs to be involved in closely monitoring the patient before, during and after the procedure.” Children’s size necessitates more detailed images of the smaller body parts — a challenge even when they are kept still under anesthesia, Dr. Finn adds. The 3-Tesla scanners are making the task easier by acquiring high-quality images in a much faster time.

The state-of-the-art imaging technology in both Westwood and Santa Monica — also including PET CT, which is increasingly used in the diagnosis of pediatric solid tumors; faster CT scanners with 64 detectors, enabling children to be evaluated without sedation; and MR enterography for patients with inflammatory bowel disease — has led to the development of new protocols for pediatric radiology that are significantly improving diagnostic capabilities, Drs. Boechat and Finn say. In many cases, the new tools are eliminating the need for more invasive catheter studies.

Dr. Boechat cautions that for all imaging of children, special attention must be paid to ensuring that protocols are pediatric specific and that the studies are interpreted by personnel who are specially trained in pediatric anatomy and pathology. “Children are not small adults,” she says. “For complicated procedures, pediatric patients are in better hands when a pediatric radiologist is interpreting the films.”

Add a comment

Please note that we are unable to respond to medical questions through the comments feature below. For information about health care, or if you need help in choosing a UCLA physician, please contact UCLA Physician Referral Service (PRS) at 1-800-UCLA-MD1 (1-800-825-2631) and ask to speak with a referral nurse. Thank you!

comments powered by Disqus