Five months baby do a head CT once, radiation is not big, parents do not need to worry too much. The baby because of the condition needs, the need for head CT examination, there is no need to blindly worry about this matter, a short-term once CT examination, on the child’s brain hair development will not be too much impact. This is like everyone usually use cell phones, long time addicted to cell phones, is also radiation, but daily occasional use of cell phones is no effect to. However, CT examination has a certain radiation, if repeated multiple times in a short period of time cranial CT examination, may have a certain impact on brain development, you can do cranial MRI examination, because there is no radiation, the safety index is relatively better. Therefore, there is no big problem for CT examination once in a while, and the radiation is also within the acceptable range, so there is no need for parents to worry too much.