Why do people with pheochromocytoma have dilated pupils?

People with pheochromocytoma may experience dilated pupils due to the overproduction of catecholamines, such as adrenaline and noradrenaline, which are hormones released by the adrenal glands. These hormones can stimulate the sympathetic nervous system, leading to increased pupil dilation (mydriasis) as part of the body's "fight or flight" response. Additionally, elevated catecholamine levels can disrupt normal autonomic control of the eye, further contributing to pupil dilation.