Ptosis is a common manifestation in ophthalmology and plastic surgery. It not only affects appearance, but may also be related to changes in visual function to a certain extent. This article will discuss the definition and classification of ptosis, pathogenesis, correlation with decreased vision, clinical manifestations, diagnostic methods and treatment strategies to clarify the potential connection between ptosis and decreased vision.
1. Definition and classification of ptosis
Eyelid ptosis, also known as ptosis, refers to the abnormal drooping of the upper eyelid edge, which blocks part or all of the pupil, resulting in difficulty in opening the eyes or limited visual field. It can be divided into two categories according to the cause : congenital ptosis and acquired ptosis :
Congenital ptosis : mostly caused by levator palpebrae superioris muscle hypoplasia or abnormal development of the oculomotor nerve;
Acquired ptosis : It can be further divided into neurogenic, myogenic, mechanical and pseudoptosis, which are commonly seen in trauma, neurological diseases, muscle diseases and skin relaxation.
Pathogenesis
The main muscles for eyelid movement are the levator palpebrae superioris and Müller muscles , whose movements are innervated by the oculomotor nerve (CN III). Any lesions that affect nerve innervation, muscle function or eyelid supporting structures may cause ptosis. Impaired levator palpebrae superioris function or abnormal nerve conduction will directly affect the height of the palpebral fissure, thereby affecting the visual field.
3. The relationship between ptosis and decreased vision
Although ptosis is essentially an anatomical change, research has shown that it may affect vision in several ways.
1. Blocking the visual axis leads to limited vision
When the upper eyelid partially or completely blocks the pupil, especially in patients with moderate to severe ptosis, it can cause obvious loss of the upper visual field. If not treated promptly in childhood, it may cause form deprivation amblyopia , which directly affects visual development.
2. Compensatory head position changes cause visual fatigue
Patients often compensate for their limited field of vision by raising their heads or frowning. This long-term unnatural head position may cause eye muscle fatigue, leading to decreased visual clarity or blurred vision. Especially after using the eyes for a long time, the subjective sense of visual fatigue is more obvious.
3. Eyelid pressure on the cornea affects visual quality
In some patients, drooping eyelids will continue to slightly compress the cornea, which may cause slight changes in corneal curvature , affect refractive status, and further lead to increased hyperopia or astigmatism.
4. Interaction between ocular lesions and comorbid factors
Certain secondary ptosis, such as diabetic oculomotor nerve palsy and myasthenia gravis, often coexists with lesions of the optic nerve, eye muscles, cornea and lens. The decline in visual function is often the result of the combined action of multiple factors.
IV. Clinical manifestations
The main symptoms of patients are unilateral or bilateral ptosis. In severe cases, the upper eyelid blocks the pupil, while in mild cases, the palpebral fissure narrows but does not affect the visual axis . Children may develop strabismus and amblyopia, while adults more commonly experience compensatory posture, eye fatigue and blurred vision.
Some patients experience hysteresis when blinking (Cogan's lid twitch) , indicating abnormal neuromuscular conduction. The degree of visual impairment varies greatly from person to person, and other examinations are needed to determine the cause.
5. Diagnostic Methods
Visual acuity and refraction examination : to assess the direct effect of ptosis on vision;
Palpebral fissure height measurement : The degree of ptosis was assessed by MRD (the distance from the pupil reflex point to the upper eyelid margin);
Assessment of levator palpebrae superioris muscle function : to determine whether muscle strength is impaired;
Imaging examination (MRI/CT) : to rule out intracranial lesions or abnormal muscle structure;
Electrophysiological examination : used to diagnose neuromuscular diseases such as myasthenia gravis;
Corneal topography : To see if eyelid pressure changes the corneal curvature.
VI. Treatment strategy
Treatment depends on the cause, severity, and age of the patient:
1. Surgery
For patients with moderate to severe ptosis that blocks the pupil, levator palpebrae superioris muscle shortening and frontalis muscle flap suspension are common surgical methods. The surgery not only improves the appearance, but also restores or expands the field of vision.
2. Drugs and supportive care
If ptosis is caused by neurogenic factors such as myasthenia gravis, systemic treatment of the underlying disease should be carried out first , including immunomodulatory drugs, anticholinesterase drugs, etc.
3. Assisted correction
Children with amblyopia can adopt a combination of occlusion therapy , refractive correction and visual training to prevent amblyopia from being caused or aggravated by eyelid occlusion.
4. Regular follow-up and comprehensive management
For patients with mild ptosis and no obvious functional impairment, a watchful waiting strategy can be adopted with regular follow-up to assess the progression and whether visual dysfunction occurs.
VII. Related Research and Literature Support
Clinical studies have shown that more than 40% of patients with moderate to severe ptosis have varying degrees of decreased visual function . Especially among those who suffer from the disease in childhood, the risk of obstructed visual development is significantly higher than that of the normal population. Adult patients often experience subjective visual fatigue, reading difficulties, or unstable night vision.
In addition, many studies have pointed out that after surgical intervention, patients' subjective visual field satisfaction and objective vision assessment were significantly improved , suggesting that ptosis correction has a positive effect on visual function.
Beauty Encyclopedia Tips:
Ptosis is not only a simple appearance problem, it may also affect visual function and quality of life. If you find abnormal ptosis of the upper eyelid, narrowing of the visual field or unstable vision, it is recommended to go to a professional ophthalmology or plastic surgery department in time to identify the cause and choose appropriate intervention measures. Especially in the developmental period of children, early intervention should be made to prevent the occurrence of amblyopia. Scientific management, early identification and standardized treatment are the key to improving visual function and aesthetic appearance.