Ptosis is an abnormal position of the upper eyelid, leading to partial or complete closure of the eye slit. Ptosis is manifested by the low position of the upper eyelid, irritation and increased fatigue of the eye, the need to tilt the head back for better vision, the development of diplopia and strabismus. Diagnosis of upper eyelid drooping includes measuring the height of the eyelid position, checking the symmetry and completeness of the movements of the eyelids of both eyes. Treatment of upper eyelid prolapse is performed surgically by resection or by creating a levator duplicature, etc.
Normally, the iris is closed by the edge of the upper eyelid by about 1.5 mm. Ptosis (blepharoptosis) is spoken of if the eyelid falls below the upper edge of the iris by 2 or more millimeters or is below the eyelid of the other eye when they are compared. The omission of the upper eyelid can be both congenital and a condition developed during life, therefore blepharoptosis is quite common among children and adults.
The omission of the upper eyelid is not only a cosmetic defect, but also interferes with the normal development and functioning of the visual analyzer, causing mechanical difficulty of vision. Correction of the omission of the upper eyelid is performed by plastic surgery and ophthalmology.
According to the time of development, congenital and acquired blepharoptosis are distinguished. Taking into account the degree of severity, the omission of the upper eyelid can be partial (the edge of the eyelid covers the upper third of the pupil), incomplete (the edge of the eyelid is lowered to half of the pupil) and complete (the upper eyelid covers the entire pupil). Ptosis can be unilateral (69%) or bilateral (31%).
Depending on the etiology of the omission of the upper eyelid, the following types of ptosis are distinguished: aponeurotic, neurogenic, myogenic, mechanical ptosis and pseudoptosis (false).
The lifting of the eyelid is carried out due to the functioning of a special muscle that raises the upper eyelid (levator), which is innervated by the oculomotor nerve. Therefore, the main causes of the ptosis may be associated either with an anomaly of the muscle that raises the eyelid, or with pathology of the oculomotor nerve.
Congenital omission of the upper eyelid may be based on underdevelopment or complete absence of the levator muscle; in rare cases, aplasia of the nuclei or pathways of the oculomotor nerve. Congenital blepharoptosis is often familial and hereditary, but it can also be caused by the pathological course of pregnancy and childbirth. Congenital omission of the upper eyelid in most cases is combined with another pathology of the visual organ: anisometropia, strabismus, amblyopia, etc.
Aponeurotic blepharoptosis most often develops against the background of involutional changes associated with the natural aging process of the body. Sometimes the reason for the ptosis are injuries of the levator aponeurosis or its damage during ophthalmic operations.
Neurogenic ptosis of the upper eyelid is a consequence of diseases of the nervous system: stroke, multiple sclerosis, oculomotor nerve paresis, meningitis, brain tumors and abscesses, etc. Ptosis of a neurogenic nature is observed in Gorner syndrome, characterized by paralysis of the cervical sympathetic nerve, occlusion of the eyeball (enophthalmos) and pupil constriction (myosis). The causes of myogenic blepharoptosis can be myasthenia gravis, muscular dystrophy, congenital myopathy, blepharophimosis.
Mechanical ptosis can be caused by retrobulbar hematoma, eyelid tumors, orbital damage, deformation of the eyelid as a result of ruptures, wounds by foreign bodies of the eye, scarring. Pseudoptosis (false, apparent omission of the upper eyelid) occurs with excess skin on the upper eyelid (blepharochalasis), strabismus, hypotension of the eyeball.
Blepharoptosis is manifested by one- or two-sided ptosis of varying degrees of severity: from partial covering to complete closure of the eye slit. Patients with drooping upper eyelid are forced to strain the frontal muscle, raise their eyebrows or tilt their head back in order to see better with the affected eye (the “stargazer” pose). The ptosis makes it difficult to perform blinking movements, which, in turn, is accompanied by increased fatigue, irritation and infection of the eyes.
Congenital blepharoptosis is often combined with strabismus, epicanthus, paresis of the superior rectus muscle. The constant covering of the eyeball with the eyelid eventually leads to the development of amblyopia. With acquired ptosis, diplopia, exophthalmos or enophthalmos, corneal sensitivity disorder are often noted.
Due to the variety of mechanisms leading to the ptosis, differential diagnosis and correction of ptosis require joint management of the patient by an ophthalmologist, neurologist, plastic surgeon.
The primary diagnosis of the omission of the upper eyelid is carried out during a visual examination. The physical examination evaluates the height of the eyelid position, the width of the eye slit, the symmetry of the eyelids of both eyes, the mobility of the eyeballs and eyebrows, the strength of the levator muscle, the position of the head, and other functional indicators.
Of the specialized ophthalmological tests, visual acuity testing, biomicroscopy, and perimetry are of the greatest diagnostic interest. If necessary, measurement of the angle of strabismus, exophthalmometry, determination of the volume of accommodation, convergence study, binocular vision study are carried out.
In case of mechanical ptosis, in order to exclude damage to bone structures in the levator region, a survey radiography of the orbit is shown. If the neurogenic nature of the ptosis is suspected, a CT (MRI) of the brain is performed, a neurologist and a neurosurgeon are consulted.
First of all, the treatment of ptosis is aimed at eliminating functional pathology and only then – at correcting the cosmetic defect.
In the case of the neurogenic nature of the ptosis, the main pathology is treated; additionally, local physiotherapy is prescribed – galvanization, UHF, paraffin therapy.
With congenital ptosis, as well as the lack of effectiveness from conservative therapy of acquired ptosis for 6-9 months, surgical ophthalmology methods are resorted to. The timing of correction of congenital blepharoptosis is differentiated: partial ptosis is operated at 13-16 years; complete ptosis, due to the likelihood of amblyopia, it is advisable to eliminate in preschool childhood.
Operations for the omission of the upper eyelid (correction of ptosis) are aimed either at shortening the muscle that raises the upper eyelid (congenital ptosis), or at shortening the levator aponeurosis (acquired ptosis).
In congenital ptosis, the levator is isolated, the muscle is plicated (shortened) by excision or duplication. In the case of severe blepharoptosis, the muscle that raises the eyelid is sewn to the frontal muscle.
The standard operation for acquired blepharoptosis consists in removing a thin strip of skin of the upper eyelid, resecting aponeurosis and fixing its lower edge to the cartilage of the upper eyelid. In plastic surgery, correction of ptosis can be combined with upper blepharoplasty.
The aesthetic and functional result of blepharoptosis correction with correctly chosen surgical tactics is usually preserved for life. When the upper eyelid is lowered due to ophthalmoplegia, treatment can achieve only a partial effect. Surgical treatment of myogenic ptosis caused by myasthenia gravis is ineffective.
The lack of treatment for the ptosis over time can lead to the development of amblyopia, deterioration of vision.