Technique cuts radiation for kids needing multiple CT scans

Pediatric neurosurgeons and neuroradiologists at Johns Hopkins Children's Center have developed an imaging technique that can cut down on the amount of radiation exposure to children who have conditions requiring multiple brain scans.

The technique, described in an article published online in the Journal of Neurosurgery: Pediatrics, uses fewer slices of the brain taken by CT scanners--seven, instead of the standard 32 to 40 slices. This approach, the authors report, can reduce radiation exposure by an average of about 92 percent per patent, compared with standard CT exams, while providing diagnostically accurate images.

"The traditional thinking has been that fewer slices would, by definition, mean less clarity and less accuracy, rendering a CT scan suboptimal, but our findings show otherwise," lead investigator Jonathan Pindrik, chief neurosurgery resident at Johns Hopkins, said in an announcement.

For the study, the researchers compared two standard CT exams with two of the lower-slice, low-dose CT exams for 50 children under the age of 17 who were being treated for hydrocephalus. They found that the limited-sequence approach produced clear and 100 percent accurate images of the brain ventricles. When capturing images of ventricular size, the limited-sequence approach resulted in a four-percent error rate. In addition, there were no false negatives in the limited-sequence approach, and three false positives.

On the whole, the researchers reported, the limited-sequence approach performed adequately and wouldn't have compromised treatment outcomes. They added that this approach could be particularly useful in pediatric emergency cases when a quick diagnosis is needed.

"We have been searching for ways to minimize radiation exposure in kids without sacrificing the diagnostic accuracy of the images--and that is no easy feat--but we believe our limited-slice CT scans achieved that balance," study investigator Edward Ahn, a pediatric neurosurgeon at the Johns Hopkins Children's Center, said.

To learn more:
- see the article in the Journal of Neurosurgery: Pediatrics
- check out the announcement from Johns Hopkins