Superior oblique myokymia
| Superior oblique myokymia | |
 | |
|---|---|
| 6 = Superior oblique muscle |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Superior oblique myokymia is a neurological disorder affecting vision and was termed by Hoyt and Keane in 1970. [1]
Causes
In 1983, Bringewald postulated that superior oblique myokymia resulted from vascular compression of the trochlear nerve (fourth cranial nerve), which controls the action of the superior oblique muscle in the eye. [2] By 1998, there had been only one reported case of compression of the trochlear nerve by vessels. [3] [4] More recently, magnetic resonance imaging experiments have shown that neurovascular compression at the root exit zone of the trochlear nerve can result in superior oblique myokymia. [5]
Epidemiology and Demographics
The onset is usually in adulthood.
Natural History, Complications, and Prognosis
The course of the disease is benign and is not commonly associated with other disorders.
Diagnosis
Symptoms
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.
Treatment
Treatment can include pharmaceutical or surgical means. The drug Oral carbamazepine (Tegretol) has been used successfully. Successful surgery options include superior oblique tenectomy accompanied by inferior oblique myectomy. [6]
Samii et al[7] and Scharwey and Samii[8] described a patient who had superior oblique myokymia for 17 years. The interposition of a Teflon pad between the trochlear nerve 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
- ↑ Hoyt WF, Keane JR. (1970). "Superior oblique myokymia: report and discussion on five case of benign intermittent uniocular microtremor". Arch Ophthalmol. 84: 461–7.
- ↑ Bringewald PR (1983). "Superior oblique myokymia". Arch Neurol. 40: 526.
- ↑ Samii M, Rosahl SK, Carvalho GA, Krzizok T (1998). "Microvascular decompression for superior oblique myokymia: first experience. Case report". J. Neurosurg. 89 (6): 1020–4. PMID 9833830.
- ↑ Scharwey K, Krzizok T, Samii M, Rosahl SK, Kaufmann H (2000). "Remission of superior oblique myokymia after microvascular decompression". Ophthalmologica. 214 (6): 426–8. PMID 11054004.
- ↑ "Superior oblique myokymia: magnetic resonance imaging support for the neurovascular compression hypothesis PMID: 11891831". Retrieved 2007-06-26.
- ↑ "Superior Oblique Myokymia 379.58". Retrieved 2007-06-25.
- ↑ Samii M, Rosahl SK, Carvalho GA, Krzizok T (1998). "Microvascular decompression for superior oblique myokymia: first experience. Case report". J. Neurosurg. 89 (6): 1020–4. PMID 9833830.
- ↑ Scharwey K, Krzizok T, Samii M, Rosahl SK, Kaufmann H (2000). "Remission of superior oblique myokymia after microvascular decompression". Ophthalmologica. 214 (6): 426–8. PMID 11054004.