Detection of experimental brain tumor in rat by computed tomography

The feasibility of the use of computerized tomographic (CT) scanning for detecting an experimental brain tumor in rats was evaluated. Tumors were induced in newborn rats by intracerebral inoculation of Rous sarcoma virus. At varying times contrast-enhanced scans were obtained on an Ohio Nuclear 2010 scanner, the brains examined, and the findings at autopsy correlated with the CT findings. Five tumors were demonstrated by CT scans and their presence confirmed at autopsy. Four small tumors were not detected by CT scans. In 1 animal, multiple tumors were demonstrated by a CT scan, and in another a large cyst was correctly diagnosed. It is concluded that the technology currently available can be used to identify some tumor-bearing animals and should be useful for following the change in size of tumors in response to therapy. Further improvements in scanner resolution should make this technique more useful for animal research.