Ophthalmoparesis refers to weakness (-paresis) or paralysis (-plegia) of one or more

extraocular muscles The extraocular muscles, or extrinsic ocular muscles, are the seven extrinsic muscles of the eye in human eye, humans and other animals. Six of the extraocular muscles, the four recti muscles, and the superior oblique muscle, superior and inferior ...

which are responsible for

eye movement Eye movement includes the voluntary or involuntary movement of the eyes. Eye movements are used by a number of organisms (e.g. primates, rodents, flies, birds, fish, cats, crabs, octopus) to fixate, inspect and track visual objects of inte ...

s. It is a physical finding in certain neurologic, ophthalmologic, and endocrine disease. Internal ophthalmoplegia means involvement limited to the pupillary sphincter and ciliary muscle. External ophthalmoplegia refers to involvement of only the extraocular muscles. Complete ophthalmoplegia indicates involvement of both.

Presentation

Causes

Ophthalmoparesis can result from disorders of various parts of the eye and nervous system: * Infection around the eye. Ophthalmoplegia is an important finding in orbital cellulitis. * The

orbit In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...

of the eye, including mechanical restrictions of eye movement, as in

Graves' disease Graves' disease, also known as toxic diffuse goiter or Basedow's disease, is an autoimmune disease that affects the thyroid. It frequently results in and is the most common cause of hyperthyroidism. It also often results in an enlarged thyro ...

. * The

muscle Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...

, as in progressive external ophthalmoplegia or Kearns–Sayre syndrome. * The

neuromuscular junction A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. Muscles require innervation to ...

, as in

myasthenia gravis Myasthenia gravis (MG) is a long-term neuromuscular junction disease that leads to varying degrees of skeletal muscle weakness. The most commonly affected muscles are those of the eyes, face, and swallowing. It can result in double vision, ...

. * The relevant cranial nerves (specifically the oculomotor, trochlear, and abducens), as in cavernous sinus syndrome or raised intracranial pressure. * The brainstem nuclei of these nerves, as in certain patterns of brainstem stroke such as Foville's syndrome. * White matter tracts connecting these nuclei, as in internuclear ophthalmoplegia, an occasional finding in

multiple sclerosis Multiple sclerosis (MS) is an autoimmune disease resulting in damage to myelinthe insulating covers of nerve cellsin the brain and spinal cord. As a demyelinating disease, MS disrupts the nervous system's ability to Action potential, transmit ...

. *

Dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

midbrain The midbrain or mesencephalon is the uppermost portion of the brainstem connecting the diencephalon and cerebrum with the pons. It consists of the cerebral peduncles, tegmentum, and tectum. It is functionally associated with vision, hearing, mo ...

structures, as in

Parinaud's syndrome Parinaud's syndrome is a constellation of neurological signs indicating injury to the dorsal midbrain. More specifically, compression of the vertical gaze center at the rostral interstitial nucleus of medial longitudinal fasciculus (riMLF). It ...

. * Certain parts of the

cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays ...

(including the frontal eye fields), as in

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

. * Toxic envenomation by mambas, taipans, and kraits.

Thiamine Thiamine, also known as thiamin and vitamin B1, is a vitamin – an Nutrient#Micronutrients, essential micronutrient for humans and animals. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosp ...

deficiency can cause ophthalmoparesis in susceptible persons; this is part of the syndrome called

Wernicke encephalopathy Wernicke encephalopathy (WE), also Wernicke's encephalopathy, or wet brain is the presence of neurological symptoms caused by biochemical lesions of the central nervous system after exhaustion of B-vitamin reserves, in particular thiamine (vi ...

. The causal pathway by which this occurs is unknown. Intoxication with certain substances, such as phenytoin, can also cause ophthalmoparesis.

Diagnosis

Classification

Ophthalmoparesis can involve any or all of the extraocular muscles, which include the superior recti, inferior recti, medial recti, lateral recti, inferior oblique and superior oblique muscles. It can also be classified by the directions of affected movements, e.g. "vertical ophthalmoparesis".

Treatment

Treatment and prognosis depend on the underlying condition. For example, in thiamine deficiency, treatment would be the immediate administration of vitamin B1.

References

External links

{{Authority control Disorders of ocular muscles, binocular movement, accommodation and refraction