A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include REFRACTIVE ERRORS; STRABISMUS; OCULOMOTOR NERVE DISEASES; TROCHLEAR NERVE DISEASES; ABDUCENS NERVE DISEASES; and diseases of the BRAIN STEM and OCCIPITAL LOBE.
Fractures of the bones in the orbit, which include parts of the frontal, ethmoidal, lacrimal, and sphenoid bones and the maxilla and zygoma.
Disorders that feature impairment of eye movements as a primary manifestation of disease. These conditions may be divided into infranuclear, nuclear, and supranuclear disorders. Diseases of the eye muscles or oculomotor cranial nerves (III, IV, and VI) are considered infranuclear. Nuclear disorders are caused by disease of the oculomotor, trochlear, or abducens nuclei in the BRAIN STEM. Supranuclear disorders are produced by dysfunction of higher order sensory and motor systems that control eye movements, including neural networks in the CEREBRAL CORTEX; BASAL GANGLIA; CEREBELLUM; and BRAIN STEM. Ocular torticollis refers to a head tilt that is caused by an ocular misalignment. Opsoclonus refers to rapid, conjugate oscillations of the eyes in multiple directions, which may occur as a parainfectious or paraneoplastic condition (e.g., OPSOCLONUS-MYOCLONUS SYNDROME). (Adams et al., Principles of Neurology, 6th ed, p240)
Diseases of the sixth cranial (abducens) nerve or its nucleus in the pons. The nerve may be injured along its course in the pons, intracranially as it travels along the base of the brain, in the cavernous sinus, or at the level of superior orbital fissure or orbit. Dysfunction of the nerve causes lateral rectus muscle weakness, resulting in horizontal diplopia that is maximal when the affected eye is abducted and ESOTROPIA. Common conditions associated with nerve injury include INTRACRANIAL HYPERTENSION; CRANIOCEREBRAL TRAUMA; ISCHEMIA; and INFRATENTORIAL NEOPLASMS.
Misalignment of the visual axes of the eyes. In comitant strabismus the degree of ocular misalignment does not vary with the direction of gaze. In noncomitant strabismus the degree of misalignment varies depending on direction of gaze or which eye is fixating on the target. (Miller, Walsh & Hoyt's Clinical Neuro-Ophthalmology, 4th ed, p641)
Abnormal protrusion of both eyes; may be caused by endocrine gland malfunction, malignancy, injury, or paralysis of the extrinsic muscles of the eye.
Diseases of the oculomotor nerve or nucleus that result in weakness or paralysis of the superior rectus, inferior rectus, medial rectus, inferior oblique, or levator palpebrae muscles, or impaired parasympathetic innervation to the pupil. With a complete oculomotor palsy, the eyelid will be paralyzed, the eye will be in an abducted and inferior position, and the pupil will be markedly dilated. Commonly associated conditions include neoplasms, CRANIOCEREBRAL TRAUMA, ischemia (especially in association with DIABETES MELLITUS), and aneurysmal compression. (From Adams et al., Principles of Neurology, 6th ed, p270)
The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.
Surgery performed on the eye or any of its parts.
Drooping of the upper lid due to deficient development or paralysis of the levator palpebrae muscle.
Bony cavity that holds the eyeball and its associated tissues and appendages.
Recession of the eyeball into the orbit.
Diseases of the fourth cranial (trochlear) nerve or its nucleus in the midbrain. The nerve crosses as it exits the midbrain dorsally and may be injured along its course through the intracranial space, cavernous sinus, superior orbital fissure, or orbit. Clinical manifestations include weakness of the superior oblique muscle which causes vertical DIPLOPIA that is maximal when the affected eye is adducted and directed inferiorly. Head tilt may be seen as a compensatory mechanism for diplopia and rotation of the visual axis. Common etiologies include CRANIOCEREBRAL TRAUMA and INFRATENTORIAL NEOPLASMS.
An autoimmune disorder of the EYE, occurring in patients with Graves disease. Subtypes include congestive (inflammation of the orbital connective tissue), myopathic (swelling and dysfunction of the extraocular muscles), and mixed congestive-myopathic ophthalmopathy.
Traumatic injury to the abducens, or sixth, cranial nerve. Injury to this nerve results in lateral rectus muscle weakness or paralysis. The nerve may be damaged by closed or penetrating CRANIOCEREBRAL TRAUMA or by facial trauma involving the orbit.
Neoplasms of the bony orbit and contents except the eyeball.
Neoplasms of the base of the skull specifically, differentiated from neoplasms of unspecified sites or bones of the skull (SKULL NEOPLASMS).
One of the paired air spaces located in the body of the SPHENOID BONE behind the ETHMOID BONE in the middle of the skull. Sphenoid sinus communicates with the posterosuperior part of NASAL CAVITY on the same side.
A nonspecific tumor-like inflammatory lesion in the ORBIT of the eye. It is usually composed of mature LYMPHOCYTES; PLASMA CELLS; MACROPHAGES; LEUKOCYTES with varying degrees of FIBROSIS. Orbital pseudotumors are often associated with inflammation of the extraocular muscles (ORBITAL MYOSITIS) or inflammation of the lacrimal glands (DACRYOADENITIS).
Diseases of the bony orbit and contents except the eyeball.
An operation for retinal detachment which reduces the size of the globe by indenting the sclera so that it approximates the retina.
A form of ocular misalignment where the visual axes diverge inappropriately. For example, medial rectus muscle weakness may produce this condition as the affected eye will deviate laterally upon attempted forward gaze. An exotropia occurs due to the relatively unopposed force exerted on the eye by the lateral rectus muscle, which pulls the eye in an outward direction.
Paralysis of one or more of the ocular muscles due to disorders of the eye muscles, neuromuscular junction, supporting soft tissue, tendons, or innervation to the muscles.
A retention cyst of the salivary gland, lacrimal sac, paranasal sinuses, appendix, or gallbladder. (Stedman, 26th ed)
A pair of ophthalmic lenses in a frame or mounting which is supported by the nose and ears. The purpose is to aid or improve vision. It does not include goggles or nonprescription sun glasses for which EYE PROTECTIVE DEVICES is available.
Disorders of one or more of the twelve cranial nerves. With the exception of the optic and olfactory nerves, this includes disorders of the brain stem nuclei from which the cranial nerves originate or terminate.
A common form of hyperthyroidism with a diffuse hyperplastic GOITER. It is an autoimmune disorder that produces antibodies against the THYROID STIMULATING HORMONE RECEPTOR. These autoantibodies activate the TSH receptor, thereby stimulating the THYROID GLAND and hypersecretion of THYROID HORMONES. These autoantibodies can also affect the eyes (GRAVES OPHTHALMOPATHY) and the skin (Graves dermopathy).
A surgical specialty concerned with the structure and function of the eye and the medical and surgical treatment of its defects and diseases.
Organizations representing specialized fields which are accepted as authoritative; may be non-governmental, university or an independent research organization, e.g., National Academy of Sciences, Brookings Institution, etc.
Diseases affecting the eye.
A medical specialty concerned with maintaining health and providing medical care to children from birth to adolescence.
Societies whose membership is limited to physicians.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
A degenerative disease of the central nervous system characterized by balance difficulties; OCULAR MOTILITY DISORDERS (supranuclear ophthalmoplegia); DYSARTHRIA; swallowing difficulties; and axial DYSTONIA. Onset is usually in the fifth decade and disease progression occurs over several years. Pathologic findings include neurofibrillary degeneration and neuronal loss in the dorsal MESENCEPHALON; SUBTHALAMIC NUCLEUS; RED NUCLEUS; pallidum; dentate nucleus; and vestibular nuclei. (From Adams et al., Principles of Neurology, 6th ed, pp1076-7)
The synapse between a neuron and a muscle.
NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.
Reproduction of data in a new location or other destination, leaving the source data unchanged, although the physical form of the result may differ from that of the source.
The act or practice of calling public attention to a product, service, need, etc., especially by paid announcements in newspapers, magazines, on radio, or on television. (Random House Unabridged Dictionary, 2d ed)
A plant genus of the family OLEACEAE. Members contain secoiridoid glucosides.
A form of interactive entertainment in which the player controls electronically generated images that appear on a video display screen. This includes video games played in the home on special machines or home computers, and those played in arcades.
Any of a group of plants formed by a symbiotic combination of a fungus with an algae or CYANOBACTERIA, and sometimes both. The fungal component makes up the bulk of the lichen and forms the basis for its name.
Revealing of information, by oral or written communication.
Component of the NATIONAL INSTITUTES OF HEALTH. It conducts and supports research on the causes, diagnosis, and treatment of diseases of the eye and visual system. It was originally part of the National Institute of Neurological Diseases and Blindness. The National Eye Institute was established in 1968.
A disorder of neuromuscular transmission characterized by weakness of cranial and skeletal muscles. Autoantibodies directed against acetylcholine receptors damage the motor endplate portion of the NEUROMUSCULAR JUNCTION, impairing the transmission of impulses to skeletal muscles. Clinical manifestations may include diplopia, ptosis, and weakness of facial, bulbar, respiratory, and proximal limb muscles. The disease may remain limited to the ocular muscles. THYMOMA is commonly associated with this condition. (Adams et al., Principles of Neurology, 6th ed, p1459)
The study of the effects of drugs on mental and behavioral activity.
A regimen or plan of physical activities designed and prescribed for specific therapeutic goals. Its purpose is to restore normal musculoskeletal function or to reduce pain caused by diseases or injuries.
The turning inward of the lines of sight toward each other.
Projection of near-IR light (INFRARED RAYS), in the 700-1000 nm region, across an object in parallel beams to an array of sensitive photodetectors. This is repeated at various angles and a mathematical reconstruction provides three dimensional MEDICAL IMAGING of tissues. Based on the relative transparency of tissues to this spectra, it has been used to monitor local oxygenation, brain and joints.
The normal decreasing elasticity of the crystalline lens that leads to loss of accommodation.
A nonspecific term referring to impaired vision. Major subcategories include stimulus deprivation-induced amblyopia and toxic amblyopia. Stimulus deprivation-induced amblyopia is a developmental disorder of the visual cortex. A discrepancy between visual information received by the visual cortex from each eye results in abnormal cortical development. STRABISMUS and REFRACTIVE ERRORS may cause this condition. Toxic amblyopia is a disorder of the OPTIC NERVE which is associated with ALCOHOLISM, tobacco SMOKING, and other toxins and as an adverse effect of the use of some medications.
Images seen by one eye.
Presence of an intraocular lens after cataract extraction.