Nelsons syndrome is a disorder that occurs in about one in four patients who have had both adrenal glands removed to treat Cushings disease. In patients with pre-existing adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas, loss of adrenal feedback following bilateral adrenalectomy can trigger the rapid growth of the tumor, leading to visual symptoms (e.g. bitemporal hemianopsia) and hyperpigmentation. The severity of the disease is dependent upon the effect of ACTH release on the skin, pituitary hormone loss from mass compression, as well as invasion into surrounding structures around the pituitary gland.The first case of Nelsons syndrome was reported in 1958 by Dr. Don Nelson. Within the past ten to twenty years, improvements have been made with identification and care for patients with Cushings disease. Techniques such as pituitary radiation therapy, ACTH assay, transsphenoidal pituitary surgery, higher resolution MRIs, and sampling of the inferior petrosal sinus have allowed physicians to pursue routes for Cushings syndrome therapy prior to consideration of bilateral adrenalectomy.Nelsons syndrome is also referred to as post adrenalectomy syndrome, a possible result of adrenalectomy performed for Cushings disease. Symptoms and signs
The common symptoms include:
hyper-pigmentation of the skin
visual disturbances
headaches
abnormally high levels of beta-MSH and ACTH
abnormal enlargements of the pituitary gland,
interruption of menstrual cycles in women

Cause
Common causes include bilateral adrenalectomy for the treatment of Cushings disease, and hypopituitarism. The onset of the disease can occur up to 24 years after a bilateral adrenalectomy has been performed, with an average of up to 15 years after.
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It is used to treat high blood pressure and heart failure. Nebivolol is used in the treatment of angina, to decrease the heart rate and contractile force. This is relevant in patients who need to decrease the oxygen demand of the heart so that the blood supplied from stenosed or constricted arteries is adequate. ACE inhibitors, angiotensin II receptor antagonists, calcium-channel blockers, and thiazide diuretics are generally preferred over beta blockers for the treatment of primary hypertension in the absence of co-morbidities. Pharmacology and biochemistry
β1-selectivity
Beta blockers help patients with cardiovascular disease by blocking β1 receptors, while many of the side-effects of these medications are caused by their blockade of β2 receptors.