(covers information from several alternate timelines)
A tomographic imaging scanner was a device capable of multiphasic resolution invented by the Daystrom Institute for use in areas where high levels of interference made the use of traditional scanning devices impossible. As of 2364 the device was still in development, but by 2370 it had been perfected and was being carried aboard the USS Enterprise.
In an alternate timeline, a tomographic imaging scanner was used to scan the interior of an anti-time eruption discovered in the Devron system. The scan revealed that the eruption was being caused by the convergence of three inverse tachyon pulses initiated in three different time periods. The timeline in which these events took place was later negated when Captain Picard prevented the formation of the eruption from occurring. (TNG: "All Good Things...")