Burt Kushner is an American pediatric ophthalmologist specializing in the diagnosis and treatment of strabismus. Kushner's contributions include demonstration of improved visual fields of patients following strabismus surgery, elucidation of torsional contribution to patients with diplopia, corticosteroid treatment of periocular capillary hemangioma, and novel hypotheses on the mechanism of "overacting" extraocular muscles.
Kushner graduated from the Northwestern University School of Medicine in 1969, and subsequently completed his internship at Evanston Hospital, ophthalmology residency at University of Wisconsin–Madison Hospital and fellowship in pediatric ophthalmology at Bascom Palmer Eye Institute.
Strabismus is a vision disorder in which the eyes do not properly align with each other when looking at an object. The eye that is pointed at an object can alternate. The condition may be present occasionally or constantly. If present during a large part of childhood, it may result in amblyopia, or lazy eyes, and loss of depth perception. If onset is during adulthood, it is more likely to result in double vision.
Amblyopia, also called lazy eye, is a disorder of sight in which the brain fails to fully process input from one eye and over time favors the other eye. It results in decreased vision in an eye that typically appears normal in other aspects. Amblyopia is the most common cause of decreased vision in a single eye among children and younger adults.
Diplopia is the simultaneous perception of two images of a single object that may be displaced horizontally or vertically in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occurring involuntarily, it results in impaired function of the extraocular muscles, where both eyes are still functional, but they cannot turn to target the desired object. Problems with these muscles may be due to mechanical problems, disorders of the neuromuscular junction, disorders of the cranial nerves that innervate the muscles, and occasionally disorders involving the supranuclear oculomotor pathways or ingestion of toxins.
Duane syndrome is a congenital rare type of strabismus most commonly characterized by the inability of the eye to move outward. The syndrome was first described by ophthalmologists Jakob Stilling (1887) and Siegmund Türk (1896), and subsequently named after Alexander Duane, who discussed the disorder in more detail in 1905.
The medial rectus muscle is a muscle in the orbit near the eye. It is one of the extraocular muscles. It originates from the common tendinous ring, and inserts into the anteromedial surface of the eye. It is supplied by the inferior division of the oculomotor nerve (III). It rotates the eye medially (adduction).
The inferior oblique muscle or obliquus oculi inferior is a thin, narrow muscle placed near the anterior margin of the floor of the orbit. The inferior oblique is one of the extraocular muscles, and is attached to the maxillary bone (origin) and the posterior, inferior, lateral surface of the eye (insertion). The inferior oblique is innervated by the inferior branch of the oculomotor nerve.
Sixth nerve palsy, or abducens nerve palsy, is a disorder associated with dysfunction of cranial nerve VI, which is responsible for causing contraction of the lateral rectus muscle to abduct the eye. The inability of an eye to turn outward, results in a convergent strabismus or esotropia of which the primary symptom is diplopia in which the two images appear side-by-side. Thus, the diplopia is horizontal and worse in the distance. Diplopia is also increased on looking to the affected side and is partly caused by overaction of the medial rectus on the unaffected side as it tries to provide the extra innervation to the affected lateral rectus. These two muscles are synergists or "yoke muscles" as both attempt to move the eye over to the left or right. The condition is commonly unilateral but can also occur bilaterally.
Hypertropia is a condition of misalignment of the eyes (strabismus), whereby the visual axis of one eye is higher than the fellow fixating eye. Hypotropia is the similar condition, focus being on the eye with the visual axis lower than the fellow fixating eye. Dissociated vertical deviation is a special type of hypertropia leading to slow upward drift of one or rarely both eyes, usually when the patient is inattentive.
Strabismus surgery is surgery on the extraocular muscles to correct strabismus, the misalignment of the eyes. Strabismus surgery is a one-day procedure that is usually performed under general anesthesia most commonly by either a neuro- or pediatric ophthalmologist. The patient spends only a few hours in the hospital with minimal preoperative preparation. After surgery, the patient should expect soreness and redness but is generally free to return home.
Henry S. Metz is an American pediatric ophthalmologist. He was the CEO of the Smith-Kettlewell Institute in San Francisco from 2003 to 2008. Much of his early research concerned eye movements and strabismus, including saccadic velocity measurements and use of botulinum toxin.
Gene Folk was an American ophthalmologist who specialized in the diagnosis and treatment of strabismus. A charter member of the American Association for Pediatric Ophthalmology and Strabismus, he later served as President of this organization. With Martin Urist, Folk helped found the "Chicago" school of strabismus, whose ideas competed with and stimulated those of Marshall M. Parks, Arthur Jampolsky, and other prominent strabismologists. During the 1950s and 1960s, Urist and Knapp's contributions led to a much improved understanding of so-called A and V "pattern" strabismus, where the amplitude of deviation varies in up- and downgaze.
Infantile esotropia is an ocular condition of early onset in which one or either eye turns inward. It is a specific sub-type of esotropia and has been a subject of much debate amongst ophthalmologists with regard to its naming, diagnostic features, and treatment.
Jane Kivlin is an American ophthalmologist who specializes in the diagnosis and treatment of pediatrics genetics and strabismus. A longstanding member of the American Association for Pediatric Ophthalmology and Strabismus, she served as President of this organization. She is well known for her contributions to the understanding of amblyopia and the ophthalmologic manifestations of shaken baby syndrome.
Cyclotropia is a form of strabismus in which, compared to the correct positioning of the eyes, there is a torsion of one eye about the eye's visual axis. Consequently, the visual fields of the two eyes appear tilted relative to each other. The corresponding latent condition – a condition in which torsion occurs only in the absence of appropriate visual stimuli – is called cyclophoria.
Stereopsis recovery, also recovery from stereoblindness, is the phenomenon of a stereoblind person gaining partial or full ability of stereo vision (stereopsis).
The Parks–Bielschowsky three-step test, also known as Park's three-step test or Bielschowsky head tilt test, is a method used to isolate the paretic extraocular muscle, particularly superior oblique muscle and trochlear nerve, in acquired vertical double vision. It was originally described by Marshall M. Parks.
Botulinum toxin therapy of strabismus is a medical technique used sometimes in the management of strabismus, in which botulinum toxin is injected into selected extraocular muscles in order to reduce the misalignment of the eyes. The injection of the toxin to treat strabismus, reported upon in 1981, is considered to be the first ever use of botulinum toxin for therapeutic purposes. Today, the injection of botulinum toxin into the muscles that surround the eyes is one of the available options in the management of strabismus. Other options for strabismus management are vision therapy and occlusion therapy, corrective glasses and prism glasses, and strabismus surgery.
The management of strabismus may include the use of drugs or surgery to correct the strabismus. Agents used include paralytic agents such as botox used on extraocular muscles, topical autonomic nervous system agents to alter the refractive index in the eyes, and agents that act in the central nervous system to correct amblyopia.
Santosh Gajanan Honavar is an Indian ophthalmologist and is currently the editor of the Indian Journal of Ophthalmology and Indian Journal of Ophthalmology - Case Reports, the official journals of the All India Ophthalmological Society; Director, Medical Services ; Director, Department of Ocular Oncology and Oculoplasty at Centre for Sight, Hyderabad; and Director, National Retinoblastoma Foundation.
Alan Brown Scott was an American ophthalmologist specializing in eye muscles and their disorders, such as strabismus. He is best known for his work in developing and manufacturing the drug that became known as Botox, research described as "groundbreaking" by the ASCRS.