However, MRI is useful because it can actually detect the labyrinthine anatomy and pinpoint the extent of disease. Moreover, we believe MRI is more sensitive than CT for small ELSTs. Pheochromocytoma Pheochromocytomas are tumors of the adrenal gland which secrete catecholamines. These can cause patients to become very hypertensive and can result in death in severe cases. Sadly, the relationship between pheochromocytoma and VHL was not fully recognized and there have been reports of death from pheochromocytoma during anesthesia and surgery for other abnormalities.
Early recognition is thus important.
We employ a combination of chemical tests and CT examinations to identify patients with pheochromocytomas. We have found that CT is very sensitive for the detection of early pheochromocytomas. What can be said is that when the lesions are very small they may not elevate the catecholamine levels. With time, however, the lesions will eventually become chemically active and then finally, symptomatic. Thus, it would appear that rather than being silent, pheochromocytomas in VHL are active even when small, but are detected earlier in patients with VHL due to presymptomatic screening.