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advances the levator aponeurosis via an anterior( skin) approach, which can be accompanied by a blepharoplasty and aid in reformation of an absent or weak skin crease. Levator aponeurosis advancement surgery can also be done via a posterior, or conjunctival, approach.
Occasionally, a ptosis may present episodically with the onset of twitches in the periocular region( blepharospasm). Blepharospasm can cause upper-eyelid ptosis, often accompanied by elevation of the lower-eyelid position, and can be so debilitating as to cause functional blindness. Blepharospasm is an approved indication for Medicare-subsidised botulinum toxin A treatment.
Treatment is delivered via minute injections in the periocular region by an experienced oculoplastic specialist and is very effective for this condition( see figure 6). Treatment often needs to be repeated at 2-3 monthly intervals.
Lower eyelid bags Lower eyelid blepharoplasty can be performed for excessive skin or herniated orbital fat, presenting as‘ bags’ in the lower eyelid. If excessive skin is present, the surgical incision is made via the skin under the eyelashes. If fat prolapse is the cause without skin redundancy, then a posterior approach is made to reposition and / or reduce orbital fat.
Brow ptosis Brow ptosis occurs with ageing, deflation and vertical descent of the soft tissues of the periorbital region. It can also occur with a seventh cranial nerve palsy. Patients may present requesting blepharoplasty surgery for what they feel is a heavy eyelid. However, the brow may have descended to, or below, the superior orbital rim level, causing heaviness and / or interference with visual field( see figure 7).
Brow elevation can be performed surgically, or temporary elevation can be achieved with botulinum toxin A injections. Unless brow descent is due to a paresis, there is no Medicare reimbursement for surgical intervention despite the procedure achieving functional and aesthetic results.
Surgery can involve a direct external brow lift, an internal browpexy via a blepharoplasty skin crease incision( for stabilisation of the brow) or more dramatic forehead lifts with risks of neuropraxia.
Ectropion Ectropion is an outward turning of the eyelid margin( see figure 8). With time, the conjunctival lining of the eyelids becomes inflamed and thickened, causing irritation and discharge. The punctum usually becomes everted, with overlying cicatricial changes contributing to a watery eye.
Senile weakening of the sling suspension of the eyelid from ageing is the main cause( see box 6). Repetitive eyelid distraction for insertion of contact lenses, eyelid rubbing in atopes and eversion of the eyelids on bed linen in floppy eyelid syndrome patients can all contribute to lid laxity.
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Figure 7. Brow ptosis.
Figure 8. Right-sided ectropion.
Patients may report long courses of chloramphenicol to no avail. Other than in cases of inflammatory skin conditions, where topical emollients and anti-inflammatories may relieve the condition, management is surgical.
Surgery involves tightening, often with shortening, of the eyelid horizontally. This may be accompanied by other procedures to reattach the lower eyelid retractor muscle or to re-invert the eyelid in the region of the punctum, thus reopposing the punctum to the tear lake. Non-hair-bearing thin skin is grafted if required when cicatricial lower-eyelid changes are noted.
Patients with mid-face hypoplasia and subsequent mid-face ptosis present a challenge. These patients may require a mid-face lift in conjunction with horizontal lid tightening. Recurrence is the main risk of ectropion surgery, with continued development of laxity, cicatricial mid-face changes and mid-face descent, particularly in those with a flat mid-face.
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Box 4. What to exclude in every case of ptosis Horner’ s syndrome Third cranial nerve palsy( complete / partial) Myasthenia gravis / chronic progressive external ophthalmoplegia Superior eyelid or orbital malignancy
Traumatic: subtarsal foreign body or penetrating eye injury, especially in a child
Patients with facial nerve palsy Patients with facial nerve palsy are complex. Obtain a history regarding the onset and any known precipitants. Examine each patient for aetiology by examining behind the ear for a possible skin cancer, in the ear for possible vesicles and examine cranial nerves. Assess corneal protective mechanisms by asking the patient to forcibly close their eyes( testing orbicularis oculi tone), test for corneal sensation and look for Bell’ s phenomenon( the upward rolling of the eye on closure).
A history of recent surgery— for example, to debulk a parotid tumour or for an acoustic tumour— may point to the cause. If no sinister cause is present, then initial management is conservative with lubricants. Progression to further intervention is dependent on corneal protective reflexes and corneal exposure signs.
If the duration of the seventh cranial nerve palsy is felt to be short term, and if signs of exposure are present, consider a surgical tarsorraphy
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or temporary induction of ptosis with a botulinum toxin A injection into the levator muscle. For a more permanent seventh cranial nerve palsy, surgical intervention includes elevating the lower lid with a horizontal lid tightening procedure, dropping the upper eyelid by loading it with a gold or platinum weight or recessing the levator palpebrae superioris. These techniques are aesthetically more pleasing than a permanent tarsorraphy.
Entropion Entropion usually affects the lower eyelid. There are three causes of entropion( see box 6). The condition involves inversion of the eyelid with both eyelash and eyelid margin rub on the cornea, causing corneal micro-abrasions; fibrovascular scar formation; and visual reduction. Entropion may be intermittent, described as a spastic entropion brought on with eyelid closure.
Asking a patient to squeeze their eyes shut or applying a drop of amethocaine, which stings, will often bring on the entropion.
The cicatricial causes are the same as those causing cicatricial conjunctivitis and include trachoma, chemical injury, scarring caused by previous generation glaucoma drops, Stevens – Johnson syndrome and ocular cicatricial pemphigoid. 2
Temporary treatment measures include barrier lubricants; taping the lower eyelid down, which is often poorly tolerated and short lasting; placement of large-diameter bandage contact lens; botulinum toxin A injections into the lower eyelid orbicularis muscle; or placement of full-thickness everting eyelid sutures. 2
Longer-term management addresses the horizontal lid laxity with a lid-tightening procedure and stabilises the lamellae of the eyelid to prevent override. There are several surgical procedures available.
Cicatricial entropions are less common. Biopsies may be required to exclude ocular cicatricial pemphigoid. Surgical repairs are more complicated, with all cicatricial entropion repairs depending on degree of entropion and cicatricial changes.
Congenital varieties of entropion are often outgrown. However, on occasion, surgical excision of a strip of orbicularis muscle and suture fixation to create a crease helps to manage this phenomenon.
Box 5. Four essential things to examine in every case of ptosis
Pupils Motility Fatiguability Subtarsal examination
Box 3. Causes of pseudoptosis
Orbital volume deficit: small globe / blind eye, absence of eye
Contralateral eyelid retraction: Graves’ disease, Parinaud’ s syndrome
Strabismus
Brow ptosis: possibly with a seventh cranial nerve palsy, disappears when eyebrow is manually elevated
Dermatochalasis
Blepharospasm: ptosis resolves with botulinum toxin A periocular injections
Mass lesion: in the orbits, sinuses or brain causing globe displacement
Box 6. Causes of ectropion and entropion
Ectropion
• Involutional: horizontal laxity of the eyelid +/- disinsertion of the lower-eyelid retractors
• Cicatricial: shortened skin in the mid-face as a result of solar damage, burns or previous surgery
• Paralytic: facial nerve palsy causing weakness of the orbicularis muscle tone
• Mechanical: tumours on or adjacent to the eyelid margin may mechanically displace the eyelid
Entropion
• Involutional( age related): most common
• Cicatricial
• Congenital
Upper eyelid retraction The upper eyelid usually overlaps the corneal – conjunctival junction, or limbus, by 1-2mm. Superior visibility of conjunctiva implies recessed upper eyelids. This can cause symptoms of exposure with dryness, irritation and watering and, if left, corneal scar formation and reduction in vision.
There are many causes of uppereyelid
retraction. The most common are unopposed levator muscle function in facial nerve palsy on the contralateral side to a unilateral ptosis, over-corrected ptosis repair and thyroid eye disease. 5
Address any thyroid dysfunction. If required, the upper eyelids can be mildly surgically dropped by removing some or all of the Muller’ s muscle. A more marked drop can be achieved by recessing the levator aponeurosis from the tarsal plate or even by performing a blepharotomy( full-thickness eyelid incision).
The extent of surgery required can be titrated to effect. Shortterm lid lowering can be achieved by injecting botulinum toxin A into the levator aponeurosis in small doses. 6 Hyaluronic acid gel fillers have also been reported successfully in the management of upper-eyelid retraction. 7 cont’ d next page
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