A study is raising concerns about CT scans given to kids during emergency room visits.

The study says the number of ER visits nationwide in which children were given CT scans surged from about 330,000 in 1995 to 1.65 million in 2008. The number of kids' ER visits didn't increase measurably.

The authors say the study didn't include dose information, but general hospitals may be less likely than pediatric facilities to use special CT protocols for kids.

CT scans in kids require adjusting doses to their smaller size, because they are more sensitive to radiation than adults.

The increases may be due to improvements in CT technology that produce clearer images quickly.

But in some cases, overuse, including fear of lawsuits, drives some doctors to order tests to avoid getting sued for a missed diagnosis.

The study is in the journal "Radiology."

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