MR imaging of rat brain glioma: Gd-DTPA versus Gd-DOTA.

The enhancement properties of gadolinium diethylenetriaminepentaacetic acid (DTPA) and gadolinium tetraazacyclododecanetetraacetic acid (DOTA) were compared using a rat glioma model. In vitro analysis included the calculation of T1 relaxivity and determination of characteristic curves. Enhancement of the intracerebral glioma was studied in 23 rats approximately 2 weeks after glioma implantation with Gd-DTPA in 12 rats and Gd-DOTA in 11 rats. Six rats were also studied 1 week after implantation. Gd-DTPA exhibited a slightly greater T1 relaxivity in vitro than Gd-DOTA. Enhancement of the glioma was also greater with Gd-DTPA than with Gd-DOTA (P less than .05).