Localization of ectopic pheochromocytomas by magnetic resonance imaging.

Magnetic resonance imaging (MRI) was utilized to localize ectopic pheochromocytomas in two patients. In both cases, MRI proved superior to computed tomography. Differentiation from surrounding tissue was excellent. MRI permits spatial localization and by assessment of signal contrast intensity provides a suggestion as to the characteristics of the tumor without the use of invasive procedures or intravenous injections. MRI should be considered as an alternative to computed tomography when evaluating patients with a suspected pheochromocytoma.