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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.
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.
The visual pathway consists of structures that carry visual information from the retina to the brain. Lesions in that pathway cause a variety of visual field defects. In the visual system of human eye, the visual information processed by retinal photoreceptor cells travel in the following way: Retina → Optic nerve → Optic chiasm a (here the ...
Magnetic resonance imaging. Hemianopsia, or hemianopia, is a visual field loss on the left or right side of the vertical midline. It can affect one eye but usually affects both eyes. Homonymous hemianopsia(or homonymous hemianopia) is hemianopic visual field loss on the same side of both eyes. Homonymous hemianopsia occurs because the right ...
Anatomy. The anterior communicating artery connects the two anterior cerebral arteries across the commencement of the longitudinal fissure. Sometimes this vessel is wanting, the two arteries joining to form a single trunk, which afterward divides; or it may be wholly, or partially, divided into two. Its length averages about 4 mm, but varies ...
Specialty. Ophthalmology. A scotoma is an area of partial alteration in the field of vision consisting of a partially diminished or entirely degenerated visual acuity that is surrounded by a field of normal – or relatively well-preserved – vision . Every normal mammalian eye has a scotoma in its field of vision, usually termed its blind spot.
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.
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]