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What is Investigation of choice in pheochromocytoma is: and explain in detail?
Answer is B (Urinary Catecholamines): Pheochromocytomas synthesize and store catecholamines which include norepinephrine, epinephrine and dopamine. The investigation of choice for diagnosis of Pheochromocytomas is determination of elevated levels of catecholamines and their methylated metabolites (metanephrines) in the plasma and urine. CT scan, MRI and MBIG Scintography are all useful diagnostic modalities for localization of pheochromocytoma once the diagnosis is established.