Search results
Results from the WOW.Com Content Network
Bitemporal hemianopsia. Bitemporal hemianopsia is the medical description of a type of partial blindness where vision is missing in the outer half of both the right and left visual field. It is usually associated with lesions of the optic chiasm, the area where the optic nerves from the right and left eyes cross near the pituitary gland.
Nelson's syndrome is a disorder that occurs in about one in four patients who have had both adrenal glands removed to treat Cushing's disease. [1] In patients with pre-existing adrenocorticotropic hormone ()-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 ...
Pituitary adenomas are tumors that occur in the pituitary gland. Most pituitary tumors are benign, approximately 35% are invasive and just 0.1% to 0.2% are carcinomas. [ 1] Pituitary adenomas represent from 10% to 25% of all intracranial neoplasms and the estimated prevalence rate in the general population is approximately 17%. [ 1][ 2]
Craniopharyngioma is a rare, usually suprasellar [ 15] neoplasm, which may be cystic, that develops from nests of epithelium derived from Rathke's pouch. [ 16][ 17] Rathke's pouch is an embryonic precursor of the anterior pituitary. [citation needed] Craniopharyngiomas are typically very slow-growing tumors.
Prolactinoma. A prolactinoma is a tumor ( adenoma) of the pituitary gland that produces the hormone prolactin. It is the most common type of functioning pituitary tumor. [ 1] Symptoms of prolactinoma are due to abnormally high levels of prolactin in the blood ( hyperprolactinemia ), or due to pressure of the tumor on surrounding brain tissue ...
Hemianopsia. Hemianopsia. Paris as seen with full visual fields. Specialty. Ophthalmology, neurology. Hemianopsia, or hemianopia, is a loss of vision or blindness ( anopsia) in half the visual field, usually on one side of the vertical midline. The most common causes of this damage are stroke, brain tumor, and trauma.
Pituitary apoplexy is bleeding into or impaired blood supply of the pituitary gland. This usually occurs in the presence of a tumor of the pituitary, although in 80% of cases this has not been diagnosed previously. The most common initial symptom is a sudden headache, often associated with a rapidly worsening visual field defect or double ...
One important variety of bilateral scotoma may occur when a pituitary tumour begins to compress the optic chiasm (as distinct from a single optic nerve) and produces a bitemporal paracentral scotoma, and later, when the tumor enlarges, the scotomas extend out to the periphery to cause the characteristic bitemporal hemianopsia.