Paediatric Ptosis

Drooping of the upper eyelid in a child. It can obstruct the visual axis (risk of deprivation amblyopia), cause astigmatism and abnormal head posture.

• Causes:
  • Congenital simple ptosis (isolated levator dysgenesis, most common; fibrosis and fatty replacement of levator muscle with poor lid fold and lagophthalmos in downgaze).
  • Blepharophimosis-ptosis-epicanthus inversus syndrome (autosomal dominant FOXL2).
  • Marcus Gunn jaw winking (trigemino oculomotor synkinesis; about 5 percent of congenital ptosis).
  • Neurogenic: congenital third nerve palsy, Horner syndrome (heterochromia, miosis, check chest and neck for neuroblastoma), ophthalmoplegic migraine.
  • Myogenic: congenital fibrosis of extraocular muscles, chronic progressive external ophthalmoplegia, myotonic dystrophy, juvenile myasthenia gravis.
  • Aponeurotic: trauma, rubbing, contact lens, chronic swelling; mechanical: eyelid tumours (neurofibroma, capillary haemangioma), chalazion, plexiform neurofibroma.
  • Pseudoptosis: contralateral lid retraction, microphthalmos, enophthalmos, hypotropia.

• Unilateral or bilateral lowered lid, with a reduced or absent lid crease, chin up head posture, brow elevation, and lid lag in downgaze (levator dysgenesis); in aponeurotic ptosis, the lid crease is high.
• Marcus Gunn: lid elevation on chewing, sucking, or opening the mouth.
• BPES: small palpebral fissures, telecanthus, epicanthus inversus, hypoplastic lids, female infertility (type 1).
• Fatigable ptosis (end of the day, variable) in juvenile myasthenia gravis.
• Associated amblyopia in about 20 percent (strabismic, anisometropic, or deprivation), astigmatism, strabismus, Bell phenomenon abnormalities.

• Measure margin reflex distance 1 (normal 4 to 5 mm), palpebral fissure height, levator function (excursion of the upper lid from downgaze to upgaze with brow held; good above 8 mm, fair 5 to 7 mm, poor 4 mm or less), lid crease position, Bell phenomenon, jaw winking, corneal sensation, tear film.
• Visual acuity, cycloplegic refraction (to detect astigmatism, anisometropia), strabismus assessment, fundus; pupil examination and iris colour to identify Horner syndrome.
• Phenylephrine 2.5 percent test (lid rise indicates Müller muscle function and Horner syndrome; in children, used less often).
• Ice pack test, acetylcholine receptor antibodies and single fibre electromyography if myasthenia suspected.
• Neuroimaging, urine catecholamines (VMA, HVA), and chest or abdominal imaging in acquired Horner syndrome of unknown cause in a child.
• Genetic tests (FOXL2) and ocular motility in syndromic cases.

• Amblyopia treatment (glasses, patching) in parallel with any surgery.
• Timing: surgery urgent (before age 1) if the lid covers the pupil with abnormal head posture or deprivation amblyopia; otherwise delay until age 3 to 4 years for accurate measurements, reliable levator function and better surgical results.
• Procedure selection by levator function:
  • Good function (above 8 mm): levator resection, with the resection amount graded to the severity of the ptosis or Müller muscle conjunctival resection in mild ptosis.
  • Fair function (5 to 7 mm): large levator resection or frontalis sling.
  • Poor function (4 mm or less): frontalis suspension with silicone rod (can be used from age 1), autogenous fascia lata (from age 3 to 4 years), or banked fascia lata or polytetrafluoroethylene; a good Bell phenomenon should be confirmed first.
  • Marcus Gunn: mild, observe; severe, levator disinsertion on the affected side with frontalis sling (unilateral).
  • BPES: medial canthoplasty (at age 3 to 5) first, then frontalis suspension at 1 year after.
• Postoperative care: lubricants (carbomer gel four times daily and ointment at night), watch for lagophthalmos, exposure keratopathy, overcorrection, undercorrection, recurrence, lid contour abnormalities, and infection; sling re-do in about 25 percent.
• Anaesthesia considerations: suspect malignant hyperthermia in myopathy, oculocardiac reflex, postoperative nausea (ondansetron 0.1 mg/kg).
• Horner or myasthenia: treat the underlying cause; ptosis crutch or lid tape for temporary relief.