Investigation of choice in pheochromocytoma is -
Diagnosis of pheochromocytoma :-

The diagnosis is typically confirmed by measurement of urinary and plasma fractionated metanephrines and catecholamines.
However there are major regional institutional and international differences in the approach to the biochemical diagnosis of pheochromocytoma and there is still no consensus as to the 'best test'.
Historically, many institutions relied upon measurement of 24 hour urinary excretion of catecholamines and total metanephrines.

- Move recently plasma fractionated metanephrines has been proposed by some investigators as superior test. 
 - Now days the diagnostic test is based upon the patients clinical presentation.
CT scan
Urinary catecholamines
MIBG scan
Urinary calcium measurement