Ptosis

Ptosis is manifested by the pathological lowering of the upper eyelid, which limits the opening of the eye. It can be one-sided or two-sided and is observed when:

1. The defeat of the striated muscle lifting the upper eyelid (m. Levator palpebrae superior).
2. Defeats the nerve that innervates this muscle (oculomotor nerve or its nucleus).
3. Apraksin opening the eyes in the syndrome of Parkinsonism and other diseases.
4. Disturbance of autonomic innervation of smooth muscle fibers of the superior tharsal muscle (Horner's syndrome).
5. False impression of the presence of ptosis, (apparent ptosis) due to retraction of this eye or exophthalmos from the opposite side.

Thus, there are three possible causes of true ptosis: partial damage to the oculomotor nerve (a branch innervating the muscle that lifts the upper eyelid) or its nucleus; damage to the sympathetic path (weakness of the tarsal muscle) and myopathy. One- sidedness of ptosis indicates the presence of limited focal lesion of the nervous system. Bilateral ptosis is almost always a sign of diffuse muscle pathology or, far more rarely, peripheral nervous system diseases. The first point of the diagnostic algorithm is the determination of the presence or absence of other external eye muscles in the patient with ptosis, the second is the examination of the pupil width and photoreaction. The detection of miosis with preservation of eye movements indicates the presence of Horner's syndrome in the patient and allows to exclude the defeat of the third cranial nerve. The slight dilatation of the pupil and the weakening of the direct reaction of this pupil to light is characteristic of the third cranial nerve and allows excluding both Horner's syndrome and myopathy. Of course, there are cases of damage to the third cranial nerve, when the parasympathetic fibers remain intact. In myopathy, in addition to ptosis, weakness of other eye muscles, facial muscles and (or) muscles of the extremities is often revealed.

Naturally, this article on content in a significant part overlaps with the chapter on acute paresis of the external eye muscles. Therefore, part of the sections of this chapter are presented rather succinctly and are intended primarily to draw attention to ptosis as a symptom that is often found only in the medical examination and is rarely an active complaint of the patient himself. If the ptosis develops gradually, some patients are not even able to tell if they have had the eyelid (eyelid) omission since the birth or it has arisen at some particular age.

A. One-sided

1. The defeat of oculomotor sympathetic innervation (Horner's syndrome)
2. Damage to the middle brain
3. Dislocation of the trunk of the third nerve
4. Intraorbital tumor and pseudotumor
5. Congenital ptosis

B. Two-sided

1. Congenital
2. Myopathy
3. "Ophthalmoplegia plus"
4. Myasthenia gravis
5. Damage to the middle brain
6. Hereditary metabolic neuropathies (Refsum's disease, Bassen-Cornzweig disease)
7. Apraxia of eyelid opening (including idiopathic blepharospasm)

[1]

Ptosis as a symptom of the defeat of different levels of the nervous system and muscles

A. Supranuclear level

Supranuclear level (with lesion at this level, ptosis can be unilateral and bilateral).

1. Unilateral ptosis: ischemic infarction in the basin of the middle cerebral artery of the contralateral hemisphere (most often), tumor, arteriovenous malformation.
2. Bilateral ptosis: can be observed with unilateral (most often - right hemispheric) and bilateral hemispheric lesion. Two-sided ptosis with paralysis of the gaze down is described with glioma of the midbrain.
3. "Ptosis" (not true) in the picture of apraxia of the opening of the eyelids: with damage to the right hemisphere or bilateral hemispheric lesion, with extrapyramidal disorders such as Huntington's chorea, Parkinson's disease, progressive supranuclear palsy, amyotrophic lateral sclerosis, Shia-Dryger syndrome, neuroacanthosis, Wilson. Dopa-sensitive apraxia of eyelid opening is described in the absence of any other symptoms of CNS damage.
4. Psychogenic ptosis (usually manifested not by true ptosis, but by psychogenic blepharospasm).
5. Ptosis in the picture of Duane's syndrome (Duane's syndrome). The syndrome is more often unilateral. 

[2], [3], [4], [5], [6], [7], [8]

B. Nuclear, radicular and axonal (oculomotor nerve) levels

Lesions at these levels are usually accompanied by other oculomotor disorders (eg, mydriasis). Damage at the nuclear level can be accompanied by bilateral ptosis.

It occurs in diseases manifested by the syndrome of the upper globular gap, orbital vertex syndrome, cavernous sinus syndrome, ruptured hole syndrome and stem syndromes in tumors, traumas, inflammatory processes, aneurysms, hyperostoses and other diseases of the skull and brain.

[9], [10], [11], [12]

C. Synaptic and Muscular Levels

Synaptic and muscular levels: myasthenia gravis, botulism, ocular myopathy, distearoidal orbitopathy, polymyositis, intraorbital processes, mechanically damaging the eyelid raising muscle, involutional ptosis in the elderly, congenital ptosis.

Intermittent ptosis with double vision is described in hereditary motor-sensory polyneuropathies of types I and II (Charcot-Marie-Tooth amyotrophy, slowly progressive ptosis can develop with diabetes, with local injury of the lifting eyelid or smooth tharsal muscle (or both muscles) due to local ischemia or hypoxia.Some ptosis, one-sided or bilateral, can be observed in the picture of Miller Fisher syndrome.

[13], [14], [15], [16], [17], [18]

A. One-sided ptosis

Horner's syndrome. This form of ptosis (paralysis of the smooth upper tarsal muscle), together with more or less pronounced miosis (paralysis of the muscle dilating the pupil), decreased congestion hyperemia (vasomotor paralysis), enophthalmos (the presence of this symptom is not necessary), often with sweating in the upper half body, make up Horner's syndrome. It should be borne in mind that, with Horner's syndrome, the difference in the width of the eye gap decreases when viewed upward (since intact and strong striated m. Levator palpebrae superior is activated).

Horner's syndrome may be a consequence of:

Damage to the homolateral central sympathetic pathways between the hypothalamus, posterior-external parts of the medulla oblongata, and lateral columns of the spinal cord. The following causes always lead to Horner's syndrome, as well as other disorders of the central nervous system:

• cardiovascular strokes, especially in the brainstem, such as:
  • the Wallenberg-Zakharchenko syndrome.
  • tumors of syringomyelia
  • progressive hemifacial atrophy

Lesions of the paravertebral sympathetic chain and its radicular afferents.

If the individual component of the paravertebral sympathetic chain is affected, then there will be no functional disorders of the nervous system. However, with lesion of the stellate ganglion, Horner's syndrome is accompanied by an anhidrosis of the face. Horner's syndrome is not observed when the (ventral) roots from C8 to T12 are affected (radicular disorders are detected). When the paravertebral sympathetic chain is damaged directly caudal to the stellate ganglion, isolated anhidrosis of the face without Horner's symptom is observed. Possible causes are:

• impact of the tumor on the paravertebral sympathetic chain (often accompanied by dysfunction of the brachial plexus);
• damage to rootlets or chains due to trauma (separation of rootlets with the formation of lower humerus pleksopatii as root syndrome C8 - T1; prevertebral hematoma);
• cluster headache, which is often accompanied by Horner's syndrome.

Damage to the middle brain, in which the nuclear complex of the third cranial nerve is located, can lead to various neurological syndromes depending on the features of the localization of brain damage. In these cases, ptosis, as a symptom of the defeat of the third nerve, is usually accompanied by other symptoms of the lesion of the oculomotor nerve, as well as nearby formations of the oral sections of the brain stem. To damage the midbrain carpal cover with only one ptosis, they should be so small (for example, a shallow lacuna) to affect only the nuclei and fibers that go to m. Levator palpebrae superior and do not affect the nearby structures. This situation is sometimes observed in the lesions of small vessels of the brain stem (usually in patients suffering from hypertension). With slowly developing processes that affect the nucleus of the oculomotor nerve, ptosis often appears after the paresis of the outer eye muscles ("the curtain falls last"). In addition, in each such case, ptosis will be accompanied by symptoms of damage to other cranial nerves or (and) conductors of the brainstem (and often bilateral).

One-sided ptosis, as a symptom of the damage to the trunk of the third nerve on the basis of the brain, is also observed in the picture of the following syndromes:

Syndrome of the upper orbital gap: III, IV, VI nerves + VI (the first branch of the trigeminal nerve). The most common causes are: pterygoid tumors, parasellar tumors, periostitis, osteomyelitis, leukemia or granulomatous infiltration in the area of the upper globule). Syndrome of the vertex of the orbit Rollet (Rollet): III, IV, VI nerves + II nerve Causes: volumetric processes behind the eyeball (retrobulbarno).

Syndrome of the cavernous sinus of Bonnet (strongonnet): III, IV, VI nerves + VIi, exophthalmos and chemosis (congestion and eyelid edema and eyelids) Causes of cavernous sinus, carotid artery aneurysm, cavernous sinus thrombosis Sousa cavernous sinus sinus syndrome { Foix}: III, IV, VI nerves + VI (first branch of the trigeminal nerve) Causes: pituitary tumors, an aneurysm of the internal carotid artery, purulent processes in the cavernous sinus, thrombosis of the cavernous sinus.

Syndrome of a torn hole of Jefferson: III, IV, VI nerves + VI. (An aneurysm of the internal carotid artery)

Intraorbital tumor and pseudotumor. The latter term is intended to mean enlarged in the volume (due to inflammation) of the extraocular muscles, and sometimes other contents of the orbit. Orbital pseudotumor is accompanied by injections of conjunctiva and mild exophthalmos, retroorbital pain, which can sometimes simulate migraine or bundle headache. Ultrasound or CT of the orbit reveals an increase in the volume of the contents of the orbit, mainly of the muscles, similar to what is revealed in prehistoric ophthalmopathy. Both the Tolosa-Hunt syndrome and the pseudotumor of the orbit respond to corticosteroid treatment. Tumor of the orbit, in addition to the above symptoms, is also accompanied by compression of the II pair and, consequently, a decrease in visual acuity (Bonnet's top of orbit syndrome).

Congenital unilateral ptosis can be a manifestation of the Gunn phenomenon, which is based on pathological connections between neurons that provide lifting of the upper eyelid and chewing. In this case, the lowered upper eyelid (usually the left one) rises when the mouth is opened or when the lower jaw moves in the opposite direction to ptosis.

[19], [20], [21], [22], [23]

B. Two-sided ptosis

Congenital ptosis, sometimes unilateral, is observed from birth, does not progress, may be accompanied by weakness of the external eye muscles. Bilateral disorders are often familial, a typical posture with a deviation of the head back.

Myopathy (oculopharyngeal muscular dystrophy) is characterized by a late onset (at 4-6 days of life) and is manifested by the defeat of oculomotor muscles (including ptosis), as well as pharyngeal muscles with swallowing disorders. There is also a form with an isolated lesion of only the oculomotor muscles, which, gradually progressing, eventually leads to total external ophthalmoplegia. As a rule, there is a certain degree of weakness and facial muscles. Ophthalmoplegia usually proceeds without doubling (ocular myopathy, or progressive external ophthalmoplegia). The diagnosis is confirmed by EMG-study. The level of CPK rises rarely (if the process extends to other striated muscles). More rarely, other forms of myopathy lead to ptosis.

Ophthalmoplegia plus or Kearns-Sayre syndrome is manifested by progressive external ophthalmoplegia and ptosis. The syndrome refers to mitochondrial encephalomyopathy and is more often observed in the form of sporadic cases (although there is also a family variant of progressive external ophthalmoplegia) and, which is typical, is accompanied by the involvement of many organs and systems. The disease begins before the age of 20 years. Obligatory signs of this disease: external ophthalmoplegia, cardiac conduction abnormalities, pigmentary degeneration of the retina, increase in protein content in the cerebrospinal fluid. As other additional symptoms, there are ataxia, hearing impairment, multiple endocrinopathy, and other manifestations. With a family version of progressive external ophthalmoplegia, weaknesses in the muscles of the neck and extremities are possible.

Myasthenia gravis. If suspected of myasthenia gravis, a simple clinical trial is needed to detect abnormal muscular fatigue - the patient is asked 30-40 times (or less) to perform those movements that suffer. In this case, closing and opening the eyes. If during this test there is an increase in ptosis (bilateral or unilateral), pharmacological tests are necessary. Intramuscular injections of anticholinesterase drugs (eg, proserin) lead to the elimination of ptosis after 30 seconds - 2 minutes for a period of several minutes to half an hour. The longer the recovery period, the less it is typical for myasthenia gravis, and should be the basis for continuing the diagnostic search.

Damage to the middle brain at the level of the nucleus of the third nerve can be accompanied by bilateral ptosis and other symptoms of damage to the oculomotor nerves and the underlying conductors of the brainstem.

Ptosis can be a manifestation of rare hereditary metabolic neuropathies, such as, for example, the disease of Refsum or Bassen-Kornzweig disease. The accompanying decrease or disappearance of tendon reflexes, as well as a slowing of the rate of excitation sweat to the nerves, indicates a lesion of the peripheral nerves. The search for metabolic disorders determines the success of the diagnosis.

Apraxin opening of the eyelids can (rarely) mimic bilateral ptosis in patients with Parkinson's disease, Huntington's chorea and other extrapyramidal diseases (see below), including in the case of facial parapaspism (described by the combination of apraxia of eyelid opening and blepharospasm).

Additional help in assessing the nosological affiliation of ptosis may be provided by the following information on its features when different levels of the nervous system are affected.

[24], [25], [26], [27], [28], [29], [30], [31], [32]