Biomaterial Database

The optic chiasm. 2011

Desmond Kidd

Department of Neuro-ophthalmology, Royal Free Hospital and Royal Free and University College Hospital Medical School, London, UK. d.kidd@medsch.ucl.ac.uk

In the first part of this chapter the anatomy and vascular supply of the chiasm are recounted, and the visual symptoms that may arise in chiasmal disease are noted. The neuro-ophthalmic signs, including the pattern of visual field defects, appearance of the optic disc, and various uncommon clinical accompaniments, are described. The second part deals with a comprehensive list of disease processes that may directly or indirectly affect the chiasm. These are divided into inflammatory disorders, including sarcoidosis, multiple sclerosis, and idiopathic chiasmitis; infective disorders, including tuberculosis; and a large section on tumors, including pituitary adenomas, cysts, and choristomas, malignant disorders, including germ cell tumors and glioma, and meningioma; and finally vascular disorders and compression due to hydrocephalus. In each case the clinical features and management of the disorder are noted, as well as the prognosis for visual improvement following treatment.

UI	MeSH Term	Description	Entries
D008279	Magnetic Resonance Imaging	Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.	Chemical Shift Imaging,MR Tomography,MRI Scans,MRI, Functional,Magnetic Resonance Image,Magnetic Resonance Imaging, Functional,Magnetization Transfer Contrast Imaging,NMR Imaging,NMR Tomography,Tomography, NMR,Tomography, Proton Spin,fMRI,Functional Magnetic Resonance Imaging,Imaging, Chemical Shift,Proton Spin Tomography,Spin Echo Imaging,Steady-State Free Precession MRI,Tomography, MR,Zeugmatography,Chemical Shift Imagings,Echo Imaging, Spin,Echo Imagings, Spin,Functional MRI,Functional MRIs,Image, Magnetic Resonance,Imaging, Magnetic Resonance,Imaging, NMR,Imaging, Spin Echo,Imagings, Chemical Shift,Imagings, Spin Echo,MRI Scan,MRIs, Functional,Magnetic Resonance Images,Resonance Image, Magnetic,Scan, MRI,Scans, MRI,Shift Imaging, Chemical,Shift Imagings, Chemical,Spin Echo Imagings,Steady State Free Precession MRI
D009897	Optic Chiasm	The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.	Chiasma Opticum,Optic Chiasma,Optic Decussation,Chiasm, Optic,Chiasma Opticums,Chiasma, Optic,Chiasmas, Optic,Chiasms, Optic,Decussation, Optic,Decussations, Optic,Optic Chiasmas,Optic Chiasms,Optic Decussations,Opticum, Chiasma,Opticums, Chiasma
D009901	Optic Nerve Diseases	Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.	Cranial Nerve II Diseases,Foster-Kennedy Syndrome,Optic Disc Disorders,Optic Disk Disorders,Optic Neuropathy,Second Cranial Nerve Diseases,Cranial Nerve II Disorder,Neural-Optical Lesion,Disc Disorder, Optic,Disk Disorder, Optic,Disorder, Optic Disc,Foster Kennedy Syndrome,Lesion, Neural-Optical,Neural Optical Lesion,Neural-Optical Lesions,Neuropathy, Optic,Optic Disc Disorder,Optic Disk Disorder,Optic Nerve Disease,Optic Neuropathies,Syndrome, Foster-Kennedy
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014786	Vision Disorders	Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).	Hemeralopia,Macropsia,Micropsia,Day Blindness,Metamorphopsia,Vision Disability,Visual Disorders,Visual Impairment,Blindness, Day,Disabilities, Vision,Disability, Vision,Disorder, Visual,Disorders, Visual,Hemeralopias,Impairment, Visual,Impairments, Visual,Macropsias,Metamorphopsias,Micropsias,Vision Disabilities,Vision Disorder,Visual Disorder,Visual Impairments
D014794	Visual Fields	The total area or space visible in a person's peripheral vision with the eye looking straightforward.	Field, Visual,Fields, Visual,Visual Field