Myokymia
Encyclopedia
Myokymia, is an involuntary, spontaneous, localized quivering of a few muscles bundles within a muscle, but which are insufficient to move a joint
.
One type is superior oblique myokymia
.
Myokymia is commonly used to describe an involuntary eyelid muscle contraction, typically involving the lower eyelid or less often the upper eyelid. It occurs in normal individuals and typically starts and disappears spontaneously. However, it can sometimes last up to three weeks. Since the condition typically resolves itself, medical professionals do not consider it to be serious or a cause for concern.
In contrast, Facial myokymia is a fine rippling of muscles on one side of the face and may reflect an underlying tumor in the brainstem (typically a brainstem glioma
), loss of myelin
in the brainstem (associated with multiple sclerosis
) or in the recovery stage of Guillain–Barré syndrome, an inflammatory polyneuropathy
that may affect the facial nerve
.
Myokymia in otherwise unrelated body parts may occur in neuromyotonia
.
Joint
A joint is the location at which two or more bones make contact. They are constructed to allow movement and provide mechanical support, and are classified structurally and functionally.-Classification:...
.
One type is superior oblique myokymia
Superior oblique myokymia
Superior oblique myokymia is a neurological disorder affecting vision 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...
.
Myokymia is commonly used to describe an involuntary eyelid muscle contraction, typically involving the lower eyelid or less often the upper eyelid. It occurs in normal individuals and typically starts and disappears spontaneously. However, it can sometimes last up to three weeks. Since the condition typically resolves itself, medical professionals do not consider it to be serious or a cause for concern.
In contrast, Facial myokymia is a fine rippling of muscles on one side of the face and may reflect an underlying tumor in the brainstem (typically a brainstem glioma
Brainstem glioma
A brainstem glioma is a cancerous glioma tumor in the brainstem.Around 75% are diagnosed in children and young adults under the age of twenty , but have been known to affect older adults as well. Brainstem gliomas start in the brain or spinal cord tissue and typically spread throughout the nervous...
), loss of myelin
Demyelinating disease
A demyelinating disease is any disease of the nervous system in which the myelin sheath of neurons is damaged. This impairs the conduction of signals in the affected nerves, causing impairment in sensation, movement, cognition, or other functions depending on which nerves are involved.The term...
in the brainstem (associated with multiple sclerosis
Multiple sclerosis
Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...
) or in the recovery stage of Guillain–Barré syndrome, an inflammatory polyneuropathy
Polyneuropathy
Polyneuropathy is a neurological disorder that occurs when many peripheral nerves throughout the body malfunction simultaneously. It may be acute and appear without warning, or chronic and develop gradually over a longer period of time. Many polyneuropathies have both motor and sensory...
that may affect the facial nerve
Facial nerve
The facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...
.
Myokymia in otherwise unrelated body parts may occur in neuromyotonia
Neuromyotonia
Neuromyotonia , also known as Isaacs' syndrome, is a form of peripheral nerve hyperexcitability that causes spontaneous muscular activity resulting from repetitive motor unit action potentials of peripheral origin.-Causes:...
.
Causes
Frequent contributing factors include: too much caffeine, high levels of anxiety, fatigue, stress, overwork, overexposure to computer/television monitors, and a lack of sleep. Use of certain drugs or alcohol may also be factors.Treatment
Many doctors commonly recommend a combined treatment of: a warm compress applied to the eyes (to relieve muscle tension, relax the muscles, and reduce swelling); a small dosage of antihistamine (to reduce any swelling that may be caused by an allergic reaction); increase bed rest (to allow muscles to rest); decrease exposure to computer screens, televisions, or harsh lighting (to allow muscles to rest); and monitor caffeine intake (too much caffeine can cause an adverse reaction such as eye twitching, but a controlled dose can serve as an effective treatment by increasing blood flow)See also
- BlepharospasmBlepharospasmA blepharospasm , is any abnormal contraction or twitch of the eyelid....
- FasciculationFasciculationA fasciculation , or "muscle twitch", is a small, local, involuntary muscle contraction and relaxation visible under the skin arising from the spontaneous discharge of a bundle of skeletal muscle fibers...
- Superior oblique myokymiaSuperior oblique myokymiaSuperior oblique myokymia is a neurological disorder affecting vision 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...
- Carnitine palmitoyltransferase II deficiencyCarnitine palmitoyltransferase II deficiencyCarnitine palmitoyltransferase II deficiency is a metabolic disorder characterized by an enzymatic defect that prevents long-chain fatty acids from being transported into the mitochondria for utilization as an energy source....