How dangerous is it to have a ct scan of the brain and another ct scan of the cervical spine (neck) done about 1 hour apart ? in 2011 with ge lightspe

Not dangerous: While you would not to have multiple ct scans performed daily, having necessary scans performed such as you are describing, pose relatively little risk. As with any medical test/procedure, the risk:benefit must be considered.

Not an issue: There is no additional risk to have the 2 exams at the same time as opposed to waiting so random interval. Indeed, having both exams together might allow the two studies to be done with less overlap and reduce total dosage. If MRI were an alternative there would be no radiation exposure.