Definition :

• Ptosis in Greek means to fall.
• Drooping of eyelids – either the upper or lower eyelid is called Ptosis.
• And Blepharoptosis is a condition in which the upper eyelid comes lower than its normal position.
• It covers about 2mm of the upper part of the Cornea.
• Ptosis mostly it leads to cosmetic blemish and also apart from that it may also lead to coverage of the pupillary area.
• This may also lead to the obstruction of the normal vision.
• Moreover 50% of the cases are congenital Ptosis.
• It may also be acquired.
• Blepharoptosis is unilateral in about 75% of the cases and in the rest of the cases it is bilateral.

Classification of Ptosis :

• Myogenic ptosis
  • Levator maldevelopment
    • Simple
    • Superior rectus weakness
  • Blepharophimosis syndrome
  • Chronic progressive external ophthalmoplegia
  • Oculopharyngial syndrome
  • Progressive muscular dystrophy
  • Myasthenia Gravis
  • And also congenital fibrosis of the extraocular muscles
• Aponeurotic ptosis
  • Senile ptosis
  • Late developing hereditary ptosis
  • Stress or trauma to levator aponeurosis
  • Following cataract surgery
  • Following other local trauma
  • Blepharochalasis
  • Associated with pregnancy
  • And also following Grave’s disease
• Neurogenic ptosis
  • Ptosis caused by lesions of third nerve
  • Post-traumatic opthalmoplegia
  • Misdirected third nerve ptosis
  • Marcuss Gunn jaw-winking ptosis
  • Horner’s syndrome
  • Ophthalmoplegic migraine
  • Multiple sclerosis
• Mechanical ptosis
• Apparent ptosis
  • Due to lack of posterior eyelid support
  • Due to hypotropia
  • And also due to dermatochalasis

 

Myogenic ptosis :

Levator maldevelopment :

• This remains as the major cause for more than 60% of the cases.
• The Levator palapebrae superioris maldevelopment is due to the deficiency of the striated muscle fibres in the muscle.
• This leads to the inelasticity of the muscle.
• And this inturn causes defective elevation of the eyelid.
• Finally, this cause blepharoptosis and also lid lag on the down gaze.
• The lid lag is because the levator palpebrae superioris fails to relax.
• This usually Sporadic but some familial cases also have been reported.
• In some cases, around 15 to 20%, it may also be associated with Superior rectus weaskness.
• This is thought to be true due to the fact that both the muscle Levator palpebrae Superioris and Superior rectus both gets originated from the same mesodermal bud.

Myasthenia Gravis :

• Myasthenia Gravis is another common cause for the Blepharoptosis seen in the clinical practice.
• This actually results due to the deficiency of Acetylcholine at the myoneural junction.
• Moreover this is thought to be associated with the autoimmune conditions like Thymus hyperplsia or dysthyroidism.
• Cases usually present along with another syndrome called Lambert Eaton syndrome or due to overuse of some drugs like Chloroquine.
• In most of the cases it is unilateral or bilateral which remians as the presenting feature.
• Later on the extra-ocular muscle also gains weakness.
• And still later on the muscle of degluttition and respiration gains weakness.
• The symptoms classically presents more in the evening and also after the exercise.
• Difficulty in degluttition and respiration mostly leads to death of the individual.
• The condition usually remains underdiagnosed in most of the cases because the diagnostic neostigmine test or tensilon tests are not performed in most of the idiopathic cases of the Blepharoptosis.

Diagnosis of Myasthenia Gravis :

• Cogan’s lid twitch sign is mostly useful in such cases.
• In this test the physician asks the patient to look upward and downwards repeatedly or to gaze upwards for a prolonged time.
• Due to fatigue, the eyelids starts flickering and gradually droops downwards.
• Neostigmin test is also very useful in such cases.
• Around 2-4 mg of the neostigmin injection (IM) after prior administration of the atropine injection.
• After that the patient is undergoes examination for the improvements of the drooping eyelid.
• Tensilon can also be (IV) but it produces effects that are only short lasting.
• Ofcourse this is safer than that of the neostigmin, but it is not readily available in the market.
• Tonometry is also an option before and after the administration of the drugs.
• This can detect mild form of the disease and this is possible due to the rise of the intraocular pressure in the positive cases.
• Detection of specific antibodies in the blood and chest laminography to detect the enlarged thymus gland can also be helpful in the diagnosis of Myasthenia gravis.
• And also thyroid function test may also remain helpful in the laboratory diagnosis.

Treatment of Myasthenia Gravis :

• Treatment always includes the oral neostigmin (Prostigmin) or Pyridostigmin (Mestinon).
• Prostigmin is short acting, used to initiate the therapeutic response.
• Pyridostigmin is long acting choline esterase inhibitor.
• And this drug pertains to maintainence of the disease.
• This is an autoimmune condition and hence systemic oral corticosteroids are used in the treatment with good results.
• Thymectomy is useful in cases of Thymomas.
• Minimal ptosis surgery is useful in long standing cases with the caution.
• Different forms of myopathies are rare conditions that occur mostly in association with affections of the extraocular muscles.
• As the Bell’s phenomenon is absent in almost all cases of the myopathies, surgical manangement of ptosis is not an indication in such cases.
• Rather crutch glasses or contact lenses is the only way of management of ptosis.

Aponeurotic ptosis :

• Aponeurotic ptosis is a common condition present in cases of old age.
• Insuch cases, either the Levator aponeurosis is either disinserted or there remains a dehiscence in the aponeurosis.
• The muscle does not completely detatach and the functioning remains normal, voluntary elevation of the lid still remains possible.
• Lid crease recedes up and so the margin crease distance increases.
• The skin is also thin and it remains transparent due to the aging process.
• And so the cornea and iris are visisble through the part of the lid above the tarsus.
• Secondary enophthalmous that occurs due to the absorption of orbital fat contributes to the drooping of eyelids.
• This is usually bilateral in nature.
• The other causes of the aponeurotic ptosis are trauma, inflammation including Grave’s disease, ocular surgeries including the cataract extraction, pregnancy, and use of certain drugs like the corticosteroids that leads to waterlogging in the tissues.
• Very rarely the aponeurotic ptosis is congenital.
• The treatment is usually surgical management.
• It includes the repair of the dehiscence, reattachment of the levator slip to the tarsal plate or vertical shortening of the aponeurosis by plication.

Neurogenic ptosis :

• Third nerve palsy ( Occulomotor nerve ) due to any lesion in its course may lead to ptosis of variable degree depending upon the amount of paresis.
• This may be congenital or due to trauma, vascular lesions, tumors, demyelination, inflammation or systemic diseases like the diabetes mellitus.
• In such cases the ocular movements are mostly affected and therefore management of the cases is essential after the assessment of the squint.
• In neurogenic ptosis, spontaneous recovery is possible upto 6 months of time period.
• And therefore, any surgical intervention scheduling after 6 months is essential after 6 months of time period.
• Horner’s syndrome :
  • Occurs due to the paralysis of the Muller’s muscle which derives its nerve supply from the sympathetic nerve.
  • Ptosis measurement due to Horner’s syndrome is around 2-3mm and the function of the levator is normal.
  • The other features of the disease include ipsilateral miosis, enophthalmos and anhydrosis of ipsilateral face.
• Ophthalmoplegic migraine :
  • It is a rare condition.
  • It is associated with temporary ptosis.
  • And this temporary condition accompanies classica features of migraine like headache and also aura.
  • After a time the defect may become permanent.
• Synkinetic ptosis :
  • This occurs usually due to the abberant connections with the central nervous system.
  • The most common variety is Marcus Gunn Jaw winking phenomenon.
  • In this condition, the trigeminal nerve supplying the muscles of mastication involves the Levator muscle.
  • Clinically, the ptotic lids shoots up while opening he mouth or while chewing or while shifting the jaw to the same side.

Mechanical ptosis :

• Excessive weight of the upper lid due to any cause like edema or mass lesion or scarring of the conjuctiva, along with the tethering of the levator muscle can lead to drooping of the upper eyelids normal muscle functions.
• Removal of the cause condition is more than enough to correct the condition.

Pseudoptosis :

• This is due to synkinetic movements that is whenever the globe goes down, the lid covers it producing ptosis when the normal eye is fixing.
• But whenever the patient fixes the hypotrophic eye the ptosis disappears.
• Sometimes in such cases true ptosis may also be present.
• In conditions like dermatochalasis the fold of skin can cover some part of the palpebral fissure giving an appearnce of ptosis.
• Sometimes in old age people, enophthalmos due to absorption of orbital fat leads to loss of the posterior support and thereby leads to ptosis.

Evaluation of ptosis :

• Firstly, History
• Secondly, Examination of eye
• Thirdly, Examination of lid
• Assessment of lid position
• Assessment of levator function
• Ocular movements
• Abnormal synkinetic movements
• Bell’s phenomenon
• Tear film
• Corneal sensations
• And also Phenylephrine tests

 

Management :

• Surgical treatment
• Fassanella servat operation
• Levator resection
• Frontalis slng surgery
  • Aponeurotic repair
• Other surgical procedures

 

Complications of Ptosis Surgery :

• Undercorrection
• Overcorrection
• Lid-lag-lagaophthalmos-keratitis
• Entropion-ectrpion-lash ptosis
• Conjuctival prolapse
• Loss of eyelashes
• Assymetrical lid contour-lid fold
• And also Hemorrhage edema