Superior oblique myokymia is a

neurological Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal ...

disorder affecting

vision Vision, Visions, or The Vision may refer to: Perception Optical perception * Visual perception, the sense of sight * Visual system, the physical mechanism of eyesight * Computer vision, a field dealing with how computers can be made to gain un ...

and was named by Hoyt and Keane in 1970. It is a condition that presents as repeated, brief episodes of movement, shimmering or shaking of the vision of one eye, a feeling of the eye trembling, or vertical/tilted vision. It can present as one or more of these symptoms. Diagnosis is most often made by the elimination of other conditions, disorders or diseases. Onset usually occurs in adulthood, and the cause is benign and is not commonly associated with other disorders. Vision alterada por SOM diurno

Causes

In 1983, Bringewald postulated that superior oblique myokymia resulted from vascular compression of the

trochlear nerve The trochlear nerve (), ( lit. ''pulley-like'' nerve) also known as the fourth cranial nerve, cranial nerve IV, or CN IV, is a cranial nerve that innervates just one muscle: the superior oblique muscle of the eye, which operates through the pul ...

(fourth cranial nerve), which controls the action of the

superior oblique muscle The superior oblique muscle, or obliquus oculi superior, is a fusiform muscle originating in the upper, medial side of the orbit (i.e. from beside the nose) which abducts, depresses and internally rotates the eye. It is the only extraocular musc ...

in the eye. By 1998, there had been only one reported case of compression of the trochlear nerve by vessels. More recently,

magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio wave ...

experiments have shown that neurovascular compression at the root exit zone of the trochlear nerve can result in superior oblique myokymia.

Diagnosis

Treatment

Treatment can include pharmaceutical or surgical means. The drug

carbamazepine Carbamazepine (CBZ), sold under the trade name Tegretol among others, is an anticonvulsant medication used primarily in the treatment of epilepsy and neuropathic pain. It is used as an adjunctive treatment in schizophrenia along with other medi ...

(Tegretol) has been used successfully. Other drugs with variable success include

gabapentin Gabapentin, sold under the brand name Neurontin among others, is an anticonvulsant medication primarily used to treat partial seizures and neuropathic pain. It is a first-line medication for the treatment of neuropathic pain caused by diabet ...

and, recently,

memantine Memantine is a medication used to slow the progression of moderate-to-severe Alzheimer's disease. It is taken by mouth. Common side effects include headache, constipation, sleepiness, and dizziness. Severe side effects may include blood clots ...

. Successful surgery options include superior oblique tenectomy accompanied by inferior oblique myectomy. However, " erall, the bulk of the ophthalmic literature would agree with the viewpoint that invasive craniotomy surgical procedures should be justified only by the presence of intractable and absolutely unbearable symptoms."''J Optom.'' 2014; 7:68–74 Vol. 7 Num. 2 Samii et al. and Scharwey and Samii described a patient who had superior oblique myokymia for 17 years. The interposition of a

Teflon Polytetrafluoroethylene (PTFE) is a synthetic fluoropolymer of tetrafluoroethylene that has numerous applications. It is one of the best-known and widely applied PFAS. The commonly known brand name of PTFE-based composition is Teflon by Chemou ...

pad between the

and a compressing artery and vein at the nerve's exit from the midbrain led to a remission lasting for a follow-up of 22 months.

References

External links

{{PNS diseases of the nervous system Eye diseases