What is optical chiasma?

Optical chiasma or optical chiasm, derived from the Greek word for crossing, is a point where two optical nerves that occur from each eye intersect on the base of the brain and form a structure in the shape of an X -shaped. On the contrary, the nasal retina provides information about the light entering the eye from the same side of the body as the eye. The fibers running from nasal retinal nerve cell cells cross in chiasm to connect with the fibers of the retinal time cells on the opposite side. In this way, the brain combines all data concerning the same side of the body in optical chiasm to form an optical tract that travels from Chiasm to the visual centers of the brain.

compression by a tumor or disruption of blood flow to the area can damage optical chiasma. Material lesions95 percent of chiasmal problems are largely due to optical chiasm, which is located approximately 0.394 inches (10 millimeters) above the pituitary gland. Patients with tumors in the area of ​​chiasmal areas may not have any symptoms or various symptoms, including headaches, double vision and reduced vision. Pit of pituitary gland, meningiomas, aneurysms, gliomas and multiple sclerosis can cause optical chiasm compression. In addition to physical examination, doctors should also scan computer tomography, laboratory tests and field of view to fully assess the patient.

lesions to optical chiasm usually cause characteristic defects of the field of vision or spatial zone with reduced perception. Tumors producing extensive compression on Chiasm are most often damaged by crossing the nasal fibers in the center of Chiasm, which bear the informatics of the temporary field of vision. A patient with a chiasmal lesion will often have bitmporal hemianopia, with blackened fields of fields on every side stEarly. The intersection occurs if the patient has a problem in the most front and lateral part of the chiasm. This characteristic defect occurs due to the compression of one optical nerve and contradictory nasal fibers that pass and pass to the anterior chiasm before curling back to the brain in the arched structure called von Willebrand's knee.

rarely compression by internal carotid arteries or anterior brain arteries will damage lateral fibers on each side of optical chiasm and create binazal hemianopia. Angiography, radiographic examination of blood vessels by dye, reveals a source of defects. The treatment of chiasmal syndrome depends on its etiology. Suitable control may include radiotherapy, standard surgery, hormone replacement or systemic steroids. In most cases, the prognosis is a breeze.