The eyelids protect the eye and keep the ocular surface moist. Eyelid malpositions can cause ocular surface disease (OSD) and threaten sight. This is in particular true for any eyelid entropion, which probably is the most common eyelid malposition, but is also true for the different forms of ectropion. This short chapter deals with the various forms of entropion and ectropion and their adequate therapies.
Entropion
Entropion is defined as an eyelid malposition, where the lid margin is inverted and directed towards the globe. The lid margin with or without lashes rubbing against the conjunctiva and the cornea causes foreign body sensation, pain and leads eventually to epithelial defects and finally to corneal scarring. Entropion should be distinguished from trichiasis and distichiasis, which present with similar symptoms, but usually need different therapy. Trichiasis is a common, acquired misdirection of eyelashes arising from their normal site of origin.
Distichiasis
is a rare, congenital condition with growth of abnormal lashes from an extra row, usually from the meibomian gland orifices. Under certain conditions, like inflammation in Stevens-Johnson syndrome, metaplastic changes in the meibomian gland orifices can induce 'acquired' distichiasis. In both trichiasis and distichiasis, the position of the lid margin is normal. If there is entropion of the lid margin this must be treated first before treatment of eyelash abnormality. Different types of entropion can be distinguished, according to the underlying etiology: (1) congenital entropion: (a) entropion and (b) epiblepharon, and (2) acquired entropion: (a) involutional entropion; (b) cicatricial entropion, and (c) acute spastic entropion.
Congenital Entropion
Congenital entropion is rare and should not be confused with epiblepharon. In congenital entropion the eyelid in its whole horizontal extension is involved and the eyelashes are directed towards the eye, but in epiblepharon the lashes are orientated more vertically. Congenital entropion tends to persist and cause keratopathy, whereas epiblepharon often resolves spontaneously.
Epiblepharon is characterized by an apparent overriding of the pretarsal orbicularis muscle and skin over the eyelid margin, causing the eyelashes to assume a vertical position. It most commonly occurs in Asians and affects the medial part of the lower eyelids. Not every child presenting with an epiblepharon, even when the lashes come into contact with the cornea, has to be operated. Often it resolves spontaneously during the first years of life.
If it fails to resolve, or if corneal irritation occurs, surgery is indicated. Recurrent attacks of conjunctivitis and persistent photophobia in children are indicators for symptomatic OSD. Surgical repair consists of circumscribed anterior eyelid lamellar shortening and tarsal fixation. An elliptical strip of skin and underlying orbicularis muscle is excised below and lateral the inferior punctum. The skin edges are sutured to the lower border of the tarsal plate or the eyelid retractors with absorbable sutures to prevent the orbicularis from overriding the lid margin. The cosmetic results are better, when the procedure is performed symmetrically on both sides. The vertical amount of skin excision should be moderate enough to prevent iatrogenic medial lower eyelid retraction causing an eversión of the lacrimal punctum.
Acquired Entropion
Acquired entropion can be either cicatricial or involutional. In addition, a form of acute spastic entropion can be defined in susceptible individuals with blepharospasm that has been induced by ocular irritation. Cicatricial entropion is due to contraction of the posterior lid lamella, involutional entropion caused by changes in the tissue structures with ageing. It is mandatory to distinguish involutional entropion from cicatricial entropion. Therefore, cicatricial changes in the conjunctiva have to be sought after. When examining a patient with entropion, the everted tarsal conjunctiva of both lower and upper eyelid should be investigated under the slit-lamp. Conjunctival and subconjunctival scar formation with or without shortening of the fornices and symblepharon formation are clinical signs for a cicatricial entropion. Severe posterior lamellar cicatrization causes in addition lid retraction.
Any condition that causes contracture of the conjunctiva can result in a cicatricial entropion. Such conditions include mechanical and chemical trauma, burns, trachoma infection (particularly in the upper eyelid) and cicatrizing conjunctivitis like topical glaucoma medication, herpes infection, Stevens-Johnson syndrome and ocular cicatricial pemphigoid. If cicatricial changes are present their cause should be established before considering surgery.
Involutional Entropion
Involutional entropion is the most common form of all entropia, and it is probably the most common eyelid malformation. Since involutional changes of the eyelid anatomy are responsible for this kind of entropion, it is therefore seen in the elderly patient. A combination of factors has been advocated to account for this kind of eyelid malposition [Jones, 1960; Collin and Rathburn, 1978]. This includes the following features: (1) horizontal eyelid laxity (desinsertion of lateral and medial canthus and/or tarsal plate laxity); (2) laxity and/or desinsertion of lower lid retractor complex, and (3) overriding of the preseptal orbic-ularis muscle over the pretarsal orbicularis. Enophthalmos due to orbital fat atrophy might aggravate the pathogenesis of involutional lower eyelid entropion, but is no longer considered a significant factor in its etiology. Any surgical treatment should address these factors.
Patient Assessment
In order to select an adequate surgical procedure for lower eyelid entropion repair, the patient has to be assessed carefully. This includes an assessment of the eyelid position and the condition of the lower eyelid. For this purpose, the simple 'snap-back' test is very useful. The lower eyelid is gently pulled downwards and away from the globe, which normally should not exceed approximately 3 mm. After releasing it, the eyelid should then spontaneously return in its normal position without an additional blink.
Therapy
The use of tape or therapeutic contact lenses temporarily can help to reduce bulbar irritation. Eventually, surgical intervention is the only effective way to correct this eyelid malposition. To achieve a long-lasting effect, the pathogenic features should be addressed. This includes horizontal lid laxity, vertical lid laxity and eyelid lamella dissociation. In the following a small number of procedures are described, which will allow one to correct the majority of involutional entropia.
Transverse/Everting Sutures
This simple, quick and everywhere (e.g. at the bedside) applicable procedure can correct any involutional entropion, if no marked lower lid laxity is present. A temporary cure for usually about 6 months is available and is particularly helpful in geriatric patients, when more invasive surgery is not indicated [Wright et al, 1999].
Transverse sutures prevent the preseptal orbicularis muscle from overriding the pretarsal part and are placed horizontally through the lid just underneath the tarsal plate [Schópfer, 1949]. Everting sutures are placed more obliquely through the lid to tighten the lower lid retractors and transfer their pull to the lid margin.
Three 5-0 Vicryl sutures are passed through the lid from the conjunctiva to the skin in the lateral two-thirds of the lid, starting from just below the border of the tarsal plate with transverse sutures and emerging through the skin just above that level in a distance of about 2mm from each other. Everting sutures run more obliquely and start lower in the fornix and emerge nearer to the lashes. The sutures are tied tightly and can be removed, if an overcorrection is present. Usually they are left for spontaneous resorption.
Wies Procedure. The Wies procedure is a transverse lid split combined with everting sutures [Wies, 1954]. By performing a horizontal full-thickness lid split, a fibrous tissue scar is induced, which permanently prevents an overriding of the preseptal orbicularis muscle. This is combined with everting sutures to tighten the lower eyelid retractors and increase their pull to the lid margin. This procedure gives good long-term results, if no horizontal lid laxity is present.
The technique consists of a horizontal full-thickness transsection of the whole of the lower eyelid about 4-5 mm below the lash line. The cut should be as horizontal as possible, and should not reach the lower punctum. Surgery is continued by passing three double-armed 5-0 Vicryl® sutures from the conjunctiva (and with it the lower lid retractors) below the lid transsection through the pretarsal orbicularis muscle to the skin above the transsection. The needles should start 1-2 mm from the conjunctival cut and emerge through the skin 1-2 mm below the lash line and about 2 mm apart. Before tying the everting sutures, the horizontal skin incision can be closed with a running 6-0 silk suture. Skin sutures are removed after 6-7 days. The everting sutures usually are left for spontaneous resorption, unless there is marked overcorrection, which in most cases is due to preexisting horizontal laxity.
Quicken Procedure. In most cases of involutional entropion a horizontal lid laxity is present. In these cases an additional full-thickness shortening is indicated. This is easiest performed by a Quickert procedure [Quickert and Rathburn, 1971], which is a Wies procedure combined with a horizontal lid shortening. The horizontal full-thickness lid split induces a fibrous tissue barrier to prevent the preseptal orbicularis muscle from overriding, the everting sutures tighten the lower eyelid retractors and increase their pull to the lid margin, and the horizontal lid shortening corrects lower lid laxity and stabilizes the lid.
A horizontal skin incision is made 4 - 5 mm from the lash line in the whole of the lower lid. Then a vertical transsection through the lid is made 5 mm medial to the lateral canthus, down to the horizontal skin incision, followed by the horizontal full-thickness transsection as in a Wies procedure, medially and laterally to the vertical incision. Finally, a full-thickness resection of excess lid margin is performed. The amount of excess tissue is estimated by overlapping the medial and the lateral end of the lid margin under slight tension. Three double-armed 5-0 Vicryl sutures are positioned in the lower conjunctival wound edge (as in the Wies procedure) before readapting the two ends of the lid margin with tarsal (6-0 Vicryl) and lid margin (6-0 silk) sutures. Surgery is continued and completed as in the Wies procedure. All silk sutures are removed after 1 week, the everting sutures left for spontaneous resorption.
The results after a Quickert procedure are usually good, the recurrence rate is as low as 3.7%.
Jones Procedure. Particularly in recurrences of lower eyelid entropion after one or more previous surgeries without horizontal laxity, and in cases where surgical trauma to the conjunctiva should be avoided, plication of the lower lid retractors through an anterior skin approach is indicated. This is in particularly helpful in lower eyelid cicatricial entropion due to ocular mucous membrane pemphigoid, when any surgical trauma to the conjunctiva should be avoided to prevent exacerbation of the disease.
With the Jones procedure the lower eyelid retractors are exposed via a skin approach, shortened, and sutures used to create a barrier to prevent the presep-tal orbicularis from overriding the pretarsal part. In the presence of additional lower eyelid laxity, particularly in the lateral canthal tendon, this procedure can be combined with a lateral tarsal strip procedure to tighten and shorten the lower eyelid.
The Jones procedure needs more dissection in the lower lid and more detailed knowledge of the anatomy.
Cicatricial Entropion
This is due to scarring of the conjunctiva and tarsal plate with shortening of the posterior lamella. Any condition that causes contracture, like chemical burns, mechanical trauma, topical glaucoma medication, ocular cicatricial mucous membrane pemphigoid and others, can induce scarring. It occurs commonly in upper and lower eyelids.
The choice of surgical procedures to correct lower eyelid cicatricial entropion is dictated by the severity of the entropion and the retraction and by the underlying cause. In ocular cicatricial pemphigoid, surgery should be confined to the anterior lamella whenever possible to avoid exacerbating the conjunctival disease. A retractor tightening procedure like the Jones procedure (see above) would be the method of choice.
Circumscribed conjunctival scars can be excised and corrected with a Z-plasty. Moderate degrees of cicatricial entropion with a minor degree of lid retraction can be managed with a tarsal fracture procedure. A horizontal incision is made through the whole length of the tarsus just below its centre down to the orbicularis muscle. Three double-armed 5-0 Vicryl sutures are passed from the lower fragment just below the incision and out through the skin immediately below the lash line. The sutures are tied to produce a mild overcorrection and removed after 2 weeks.
In severe cicatricial lower lid entropion with more severe degree of lid retraction, a posterior lamellar graft is indicated. The tarsoconjunctiva is lengthened with a graft, which is inserted near the lid margin to allow eversión. A piece of full-thickness buccal mucosa, tarsal plate, hard palate, ear cartilage or donor sclera is sutured with running 6-0 Vicryl sutures between the superior and inferior fragment of the horizontally divided lower tarsal plate. The lid margin is hold everted and the graft firmly apposed to its bed with everting sutures passed through the graft and tied on the skin just below the lashes.
Acute Spastic Entropion
Topical therapy of the underlying cause of ocular irritation may reverse the eyelid malposition. If this is not the case, a permanent entropion with usually involutional components may ensue, which will require surgical intervention according to the guidelines given before.
Upper Eyelid Entropion
Upper eyelid entropion is an eyelid malposition in which the upper eyelid margin is turned inwards against the globe. It can be responsible for severe OSD and ocular morbidity. It is relatively uncommon in the northern hemisphere in contrast to a number of countries in more arid areas of the world, where trachoma is endemic.
The condition can be congenital, which is rather rare, but is mainly caused by cicatricial changes of the posterior upper eyelid lamella. Any trauma, either mechanical or chemical, and infection to the conjunctiva can cause an upper eyelid entropion. Worldwide, trachoma is the most common cause of this upper eyelid malposition, other causes are listed in table. In addition to taking a careful history, a complete ocular examination with eversión of the posterior lamella and the superior fornix is essential to determine the etiology.
Upper eyelid trachoma may be further classified according to its severity as mild, moderate or severe. This is essential for choosing the most appropriate surgical procedure. However, first it is important to establish the diagnosis of upper eyelid entropion and differentiate this from simple trichiasis. This helps to avoid unnecessary and often useless epilation efforts.
Therapy
Anterior Lamellar Repositioning
This procedure is indicated in mild to moderate forms of upper eyelid entropion. It is easy to perform, safe and corrects the majority of upper lid entropia in the northern hemisphere [Hintschich, 1997]. The surgery divides the anterior from the posterior lamella of the upper eyelid, repositions the anterior lamella superiorly and sutures it to the tarsal plate at a higher level. This is often combined with a lid split at the grey line of the lid margin, which enhances the everting effect to the lid margin. This procedure requires a stable upper tarsal plate.
The superior tarsal plate is completely freed from the overlying orbicularis muscle down to the roots of the lashes through a skin crease incision. The entire length of the lid margin is split in the grey line, just anteriorly to the orifices of the meibomian glands, to a depth of 1-2 mm. Five to six 6-0 double-armed Vicryl sutures are anchored in the upper third of the anterior tarsal plate and then passed out through orbicularis and skin, just above the lash line. By closing these sutures, the anterior lamella is lifted and the lash-bearing part of the lid margin is everted. The split is allowed to granulate and the sutures can be left for spontaneous resorption.
In more severe forms of upper eyelid entropion a tarsal wedge resection or a rotation of the terminal tarsus can be performed. In cases of post-traumatic upper eyelid entropion, particularly after severe burns, the tarsal plate tends to be thin and unstable. This situation is often combined with upper lid retraction, conjunctival scarring and an upper fornix shortening. Under such conditions, none of the aforementioned techniques are applicable. A posterior lamellar graft is then indicated to stabilize and lengthen the upper eyelid. An autologous graft is put between the upper eyelid margin or the remnant of the tarsal plate and the recessed upper lid retractors.
A graft from the hard palate is favorable because it combines some stiffness with mucous membrane lining and is ideal for this kind of upper eyelid correction. Sutures and knots always should be covered by tissue to avoid corneal damage. Any aberrant or misdirected lashes and lid margin malpositions can be corrected at the same time, if necessary, by a full-thickness wedge excision.
It is important to correct cicatricial upper eyelid entropium before starting with any visual rehabilitative procedures, such as keratoplasty. Otherwise the continuing mechanical stress to the ocular surface caused by the lid malposition will jeopardize the result of any of these procedures. In consequence, one might be forced to perform lid surgery earlier than 6 months after the trauma in order to prevent ongoing damage to the ocular surface, although this can be associated with a higher failure rate of the surgery. Usually one waits for at least 6 months until healing and scarring is completed before corrective and reconstructive procedures are performed.
Ectropion
Lower eyelid ectropion is an eyelid malposition in which the lower eyelid margin is turned away from the globe. This condition can be classified into five categories according to the underlying etiology: (1) congenital ectropion and (2) acquired ectropion: (a) involutional ectropion; (b) cicatricial ectropion; (c) paralytic ectropion, and (d) mechanical ectropion.
Any severe ectropion with secondary lagophthalmos cannot only cause continuing epihora, but also OSD with exposure keratopathy and finally corneal ulceration. For therapy, it is important to be able to classify the actual type of ectropion so that the correct management is chosen based on the underlying cause. However, more than one etiological factor in one individual patient may be present, e.g. ongoing epiphora in a neglected involutional ectropion may lead to secondary cicatricial changes in the skin. This induces a vicious circle, which is increasingly difficult to reverse the longer the surgery is delayed. One should always look for cicatricial changes in the skin - either a general tightness, which is accentuated by asking the patient to look up and open the mouth, or a linear scar. Failure to recognize a cicatricial component is a common cause of surgical failure. Horizontal lid laxity and lateral or medial tendon weakness is assessed as for involutional entropion. Lower eyelid ectropion in facial nerve palsy mostly is associated with other abnormalities of facial nerve function, e.g. inability to lift the forehead or other signs of facial muscular weakness.
Congenital Ectropion
The majority of patients with congenital ectropion suffer from cicatricial ectropion due to a generalized shortage of the periorbital skin. Singular congenital ectropion is rare; it is mainly associated with additional abnormalities as in blepharophimosis syndrome, Down syndrome or ichthyosis. A congenital facial palsy like in a Moebius syndrome causes a paralytic ectropion.
Patients with shortage of skin require full-thickness skin grafting (see below). This surgery is purely functional and the aesthetic results are less favorable in comparison to the results in adults. However, in cases of severe cicatricial ectropion with lagophthalmos causing keratopathy in young children, skin grafting procedures should not be delayed to prevent them from sight-threatening complications. Tarsorrhaphies never work sufficiently in these cases and will only complicate the situation and delay a definite correction.
Acquired Ectropion
Involutional Ectropion
The most common type of ectropion is the involutional ectropion with its variety of involutional tissue changes including horizontal lid laxity, weakness of the retractors and a dissociation between the lamellae. The surgical procedure should address the underlying etiological factors, as mentioned above. In general, the surgery of an involutional ectropion, particularly of the medial eyelid with punctual eversión, medial tendon laxity, chronic conjunctival exposure and lacrimal pump insufficiency is difficult and the results often are less favorable compared to other lid malformations.
The treatment of involutional lower eyelid ectropion is to correct the lower lid laxity by shortening the lid in the area of maximum laxity. This can be carried out centrally or laterally, under a blepharoplasty flap which allows excess skin and fat to be removed for improved aesthetics, at the lateral canthus or medially just lateral to the punctum. Inverting sutures can support the correction of an everted lid margin. Inversion can be further helped if the posterior lamella of the lid is shortened and the lower lid retractors tightened with the excision of a diamond of tarsoconjunctiva and lower lid retractor plication. If the lid laxity is maximum in the medial canthal tendon this can be tightened with a medial canthal suture or a medial canthal full-thickness resection. Such a medial canthal resection involves cutting the inferior canaliculus that can be marsupialized into the conjunctival sac without necessarily causing epiphora.
Full-Thickness Wedge Excision
A full-thickness pentagon of lid is resected from the area of maximum lid laxity. If there is general lid laxity, the excision is performed in the lateral third of the lower eyelid. The amount of excision, which is necessary for correction, is assessed by overlapping the medial and the lateral portion of the lid gently. The lid transsection has to be perpendicular to the lid margin. Once the pentagon is excised, small vessels are cauterized, and the lid defect is repaired.
Lid Margin Repair
Two or three 6-0 Vicryl sutures on a half circle needle are passed with a horizontal partial-thickness bite into the tarsal plate of one wound edge and then into the tarsal plate of the other wound edge at the corresponding height entering from its conjunctival side. Before closing the sutures, the alignment of the lid margin is checked. Then a silk suture is passed through the grey line and in line with it and closed, leaving its ends long. An additional silk suture is passed in the lash line, some more in the skin to close it. The long ends of the grey line suture are caught and knotted with the skin sutures to prevent the grey line suture from rubbing against the globe. The silk sutures can be removed after 1 week.
Lazy T Procedure
This procedure corrects a medial ectropion with horizontal lid laxity. A medial full-thickness lid resection is combined with an excision of a diamond-shaped part of conjunctiva and subconjunctival tissue, which is closed with an inverting suture. The diamond excision is carried out in the conjunctiva immediately below the lower punctum. One needle of a double-armed 6-0 absorbable suture is passed through the superior apex of the diamond, the other through the conjunctiva below its inferior apex. With this needle, parts of the lower lid retractors are picked up, which are best found lateral to the diamond. Both needles are passed through orbicularis and skin and tied anteriorly. This suture not only closes the diamond excision, but also increases the inversion of the punctum, particularly on down-gaze.
Lateral Tarsal Strip Procedure
This procedure is an excellent method to correct any horizontal lower lid laxity and can be used for both entropion and ectropion repair [Anderson and Gordy, 1979]. It can be combined either with inverting or everting procedures, depending on the underlying pathology. If there is significant medial canthal laxity and the procedure would cause an unacceptable lateral displacement of the punctum, a lateral tarsal strip procedure should not be used (or only in combination with a medial tendon reinforcement).
The principle of this procedure is based on a (re)attachment of the lateral part of the tarsal plate to the periorbital tissue adjacent to the bony orbital rim inside the zygomatic arch. To attain a good result it is mandatory to free the lateral part of the tarsal plate from any epithelial tissues and to suture it as posterior as possible inside the orbital rim. This is necessary to firstly avoid the complication of inclusion cysts and secondly to reach the best alignment of the lid margin to the globe.
Usually monofile non-absorbable sutures, like 6-0 Prolene, are used, but long-acting absorbable sutures, like 5-0 Vicryl, also will work. The lateral canthal area and the bone is approached by an approximately 10 mm horizontal skin incision starting from the lateral canthus. The lower limb of the lateral canthal tendon is cut. The lateral part of the lower lid tarsal plate is completely denuded by removing the lid margin with all lash roots, the orbicularis muscle and the conjunctiva. In cases of a stretched tarsal plate causing marked laxity, a piece of tarsus can be resected. If the tarsal plate is too short to form a lateral canthal tendon, which reaches the periorbit, a periosteal flap can be formed. Such a flap can easily be dissected by incising the periosteum at the outer surface of the zygomatic bone, leaving the junction in the inner part of the arch intact. The lateral tarsal strip is sutured with a double-armed suture to either the periorbital tissue or the periosteal flap. The lateral canthus is restored with a hidden simple suture and the skin is closed.
Cicatricial Ectropion
Cicatricial ectropion is due to a shortage of skin. This can be either congenital or acquired. If the skin shortage is local it can be corrected with a Z-plasty and if it is general it should be corrected by the addition of skin either as a flap or a free graft. The treatment of cicatricial ectropion with tarsorrhaphy is useless and a waste of time. However, any additional lid laxity can be corrected with a lid shortening procedure.
Skin Grafting. In the periorbital area, full-thickness grafts are preferable to split-thickness grafts. Suitable donor sites are the upper eyelid (ipsi- or contralateral), the pre-or retroauricular site, and the inner side of the upper arm or the supra-clavicular fossa.
The recipient site must be prepared carefully, any subcutaneous scar tissue causing traction be excised and bleeding stopped. Traction sutures help to keep the bed stretched. The graft should be as thin as possible and not oversized, but just fitted into the defect to prevent it from developing a wrinkled surface. The graft should be left undisturbed for at least 2-3 days with a moist pressure dressing applying continuous pressure onto the stretched graft.
Paralytic Ectropion
A paralytic ectropion is caused by a seventh nerve palsy and due to a lack of normal innervation of the orbicularis muscle. Failure of normal lid closure with lower lid laxity and ectropion, upper eyelid retraction and brow ptosis are the clinical signs.
Lagophthalmos can cause severe OSD with corneal epithelial defects. The risk of significant morbidity is higher in patients with peripheral seventh nerve palsy, severe lagophthalmos, missing Bell's phenomenon and reduced corneal sensibility. In these patients, if no early spontaneous restoration of facial nerve function can be observed, an early surgical intervention to improve the lid closure is indicated. This can be either a temporary tarsorrhaphy or a botulinus toxin injection. The lower eyelid primarily requires support to hold the lid up against gravity. Lower eyelid ectropion repair is best performed by a lateral tarsal strip procedure. This can by combined with a medial canthoplasty (Otis-Lee procedure) [Lee, 1951]. With this simple procedure the upper and lower lid margins medial to the lacrimal puncta are sutured together permanently. This reduces the interpalpebral distance at the medial canthus and brings the lacrimal puncta into the tear film. Lid laxity can be corrected medially with medial can-thai sutures or in long-standing cases with a medial canthal resection.
Before putting weights into the upper eyelid, it is important to correct any lower lid ectropion and upper eyelid retraction first. Lid loading should be the last and not the first surgical procedure!
Floppy Eyelid Syndrome
Upper eyelid ectropion can be part of the 'floppy eyelid syndrome' [Culbertson and Ostler, 1981] which includes easily everted upper eyelids, chronic papillary conjunctivitis, and non-specific irritation. The typical patient with FES is male and obese with symptoms of foreign body sensation, morning tearing, mattering and redness, photophobia, and awakening with an everted eyelid. 70% of the patients present corneal involvement. The pathophysiology of FES is probably multifactorial with systemic mechanisms (obstructive sleep apnea) and mechanical mechanisms (sleeping preference).
Regardless of the cause, most patients benefit from surgical eyelid tightening after conservative measures such as shields, lubrication, and weight loss have failed to provide relief. To date, the literature on the surgical treatment of FES recommends pentagonal wedge resection beginning at the lateral third of the eyelid or a lateral tarsal strip procedure. These simple approaches are extremely helpful in treating OSD in such patients [Culbertson and Tseng, 1994]. In addition, a number of modifications have been described recently -including medial upper eyelid shortening - for which the reader is directed to the primary literature [Moore et al, 1996; Periman and Sires, 2002; Valenzuela and Sullivan, 2005].
Entropion
Entropion is defined as an eyelid malposition, where the lid margin is inverted and directed towards the globe. The lid margin with or without lashes rubbing against the conjunctiva and the cornea causes foreign body sensation, pain and leads eventually to epithelial defects and finally to corneal scarring. Entropion should be distinguished from trichiasis and distichiasis, which present with similar symptoms, but usually need different therapy. Trichiasis is a common, acquired misdirection of eyelashes arising from their normal site of origin.
Distichiasis
is a rare, congenital condition with growth of abnormal lashes from an extra row, usually from the meibomian gland orifices. Under certain conditions, like inflammation in Stevens-Johnson syndrome, metaplastic changes in the meibomian gland orifices can induce 'acquired' distichiasis. In both trichiasis and distichiasis, the position of the lid margin is normal. If there is entropion of the lid margin this must be treated first before treatment of eyelash abnormality. Different types of entropion can be distinguished, according to the underlying etiology: (1) congenital entropion: (a) entropion and (b) epiblepharon, and (2) acquired entropion: (a) involutional entropion; (b) cicatricial entropion, and (c) acute spastic entropion.
Congenital Entropion
Congenital entropion is rare and should not be confused with epiblepharon. In congenital entropion the eyelid in its whole horizontal extension is involved and the eyelashes are directed towards the eye, but in epiblepharon the lashes are orientated more vertically. Congenital entropion tends to persist and cause keratopathy, whereas epiblepharon often resolves spontaneously.
Epiblepharon is characterized by an apparent overriding of the pretarsal orbicularis muscle and skin over the eyelid margin, causing the eyelashes to assume a vertical position. It most commonly occurs in Asians and affects the medial part of the lower eyelids. Not every child presenting with an epiblepharon, even when the lashes come into contact with the cornea, has to be operated. Often it resolves spontaneously during the first years of life.
If it fails to resolve, or if corneal irritation occurs, surgery is indicated. Recurrent attacks of conjunctivitis and persistent photophobia in children are indicators for symptomatic OSD. Surgical repair consists of circumscribed anterior eyelid lamellar shortening and tarsal fixation. An elliptical strip of skin and underlying orbicularis muscle is excised below and lateral the inferior punctum. The skin edges are sutured to the lower border of the tarsal plate or the eyelid retractors with absorbable sutures to prevent the orbicularis from overriding the lid margin. The cosmetic results are better, when the procedure is performed symmetrically on both sides. The vertical amount of skin excision should be moderate enough to prevent iatrogenic medial lower eyelid retraction causing an eversión of the lacrimal punctum.
Acquired Entropion
Acquired entropion can be either cicatricial or involutional. In addition, a form of acute spastic entropion can be defined in susceptible individuals with blepharospasm that has been induced by ocular irritation. Cicatricial entropion is due to contraction of the posterior lid lamella, involutional entropion caused by changes in the tissue structures with ageing. It is mandatory to distinguish involutional entropion from cicatricial entropion. Therefore, cicatricial changes in the conjunctiva have to be sought after. When examining a patient with entropion, the everted tarsal conjunctiva of both lower and upper eyelid should be investigated under the slit-lamp. Conjunctival and subconjunctival scar formation with or without shortening of the fornices and symblepharon formation are clinical signs for a cicatricial entropion. Severe posterior lamellar cicatrization causes in addition lid retraction.
Any condition that causes contracture of the conjunctiva can result in a cicatricial entropion. Such conditions include mechanical and chemical trauma, burns, trachoma infection (particularly in the upper eyelid) and cicatrizing conjunctivitis like topical glaucoma medication, herpes infection, Stevens-Johnson syndrome and ocular cicatricial pemphigoid. If cicatricial changes are present their cause should be established before considering surgery.
Involutional Entropion
Involutional entropion is the most common form of all entropia, and it is probably the most common eyelid malformation. Since involutional changes of the eyelid anatomy are responsible for this kind of entropion, it is therefore seen in the elderly patient. A combination of factors has been advocated to account for this kind of eyelid malposition [Jones, 1960; Collin and Rathburn, 1978]. This includes the following features: (1) horizontal eyelid laxity (desinsertion of lateral and medial canthus and/or tarsal plate laxity); (2) laxity and/or desinsertion of lower lid retractor complex, and (3) overriding of the preseptal orbic-ularis muscle over the pretarsal orbicularis. Enophthalmos due to orbital fat atrophy might aggravate the pathogenesis of involutional lower eyelid entropion, but is no longer considered a significant factor in its etiology. Any surgical treatment should address these factors.
Patient Assessment
In order to select an adequate surgical procedure for lower eyelid entropion repair, the patient has to be assessed carefully. This includes an assessment of the eyelid position and the condition of the lower eyelid. For this purpose, the simple 'snap-back' test is very useful. The lower eyelid is gently pulled downwards and away from the globe, which normally should not exceed approximately 3 mm. After releasing it, the eyelid should then spontaneously return in its normal position without an additional blink.
Therapy
The use of tape or therapeutic contact lenses temporarily can help to reduce bulbar irritation. Eventually, surgical intervention is the only effective way to correct this eyelid malposition. To achieve a long-lasting effect, the pathogenic features should be addressed. This includes horizontal lid laxity, vertical lid laxity and eyelid lamella dissociation. In the following a small number of procedures are described, which will allow one to correct the majority of involutional entropia.
Transverse/Everting Sutures
This simple, quick and everywhere (e.g. at the bedside) applicable procedure can correct any involutional entropion, if no marked lower lid laxity is present. A temporary cure for usually about 6 months is available and is particularly helpful in geriatric patients, when more invasive surgery is not indicated [Wright et al, 1999].
Transverse sutures prevent the preseptal orbicularis muscle from overriding the pretarsal part and are placed horizontally through the lid just underneath the tarsal plate [Schópfer, 1949]. Everting sutures are placed more obliquely through the lid to tighten the lower lid retractors and transfer their pull to the lid margin.
Three 5-0 Vicryl sutures are passed through the lid from the conjunctiva to the skin in the lateral two-thirds of the lid, starting from just below the border of the tarsal plate with transverse sutures and emerging through the skin just above that level in a distance of about 2mm from each other. Everting sutures run more obliquely and start lower in the fornix and emerge nearer to the lashes. The sutures are tied tightly and can be removed, if an overcorrection is present. Usually they are left for spontaneous resorption.
Wies Procedure. The Wies procedure is a transverse lid split combined with everting sutures [Wies, 1954]. By performing a horizontal full-thickness lid split, a fibrous tissue scar is induced, which permanently prevents an overriding of the preseptal orbicularis muscle. This is combined with everting sutures to tighten the lower eyelid retractors and increase their pull to the lid margin. This procedure gives good long-term results, if no horizontal lid laxity is present.
The technique consists of a horizontal full-thickness transsection of the whole of the lower eyelid about 4-5 mm below the lash line. The cut should be as horizontal as possible, and should not reach the lower punctum. Surgery is continued by passing three double-armed 5-0 Vicryl® sutures from the conjunctiva (and with it the lower lid retractors) below the lid transsection through the pretarsal orbicularis muscle to the skin above the transsection. The needles should start 1-2 mm from the conjunctival cut and emerge through the skin 1-2 mm below the lash line and about 2 mm apart. Before tying the everting sutures, the horizontal skin incision can be closed with a running 6-0 silk suture. Skin sutures are removed after 6-7 days. The everting sutures usually are left for spontaneous resorption, unless there is marked overcorrection, which in most cases is due to preexisting horizontal laxity.
Quicken Procedure. In most cases of involutional entropion a horizontal lid laxity is present. In these cases an additional full-thickness shortening is indicated. This is easiest performed by a Quickert procedure [Quickert and Rathburn, 1971], which is a Wies procedure combined with a horizontal lid shortening. The horizontal full-thickness lid split induces a fibrous tissue barrier to prevent the preseptal orbicularis muscle from overriding, the everting sutures tighten the lower eyelid retractors and increase their pull to the lid margin, and the horizontal lid shortening corrects lower lid laxity and stabilizes the lid.
A horizontal skin incision is made 4 - 5 mm from the lash line in the whole of the lower lid. Then a vertical transsection through the lid is made 5 mm medial to the lateral canthus, down to the horizontal skin incision, followed by the horizontal full-thickness transsection as in a Wies procedure, medially and laterally to the vertical incision. Finally, a full-thickness resection of excess lid margin is performed. The amount of excess tissue is estimated by overlapping the medial and the lateral end of the lid margin under slight tension. Three double-armed 5-0 Vicryl sutures are positioned in the lower conjunctival wound edge (as in the Wies procedure) before readapting the two ends of the lid margin with tarsal (6-0 Vicryl) and lid margin (6-0 silk) sutures. Surgery is continued and completed as in the Wies procedure. All silk sutures are removed after 1 week, the everting sutures left for spontaneous resorption.
The results after a Quickert procedure are usually good, the recurrence rate is as low as 3.7%.
Jones Procedure. Particularly in recurrences of lower eyelid entropion after one or more previous surgeries without horizontal laxity, and in cases where surgical trauma to the conjunctiva should be avoided, plication of the lower lid retractors through an anterior skin approach is indicated. This is in particularly helpful in lower eyelid cicatricial entropion due to ocular mucous membrane pemphigoid, when any surgical trauma to the conjunctiva should be avoided to prevent exacerbation of the disease.
With the Jones procedure the lower eyelid retractors are exposed via a skin approach, shortened, and sutures used to create a barrier to prevent the presep-tal orbicularis from overriding the pretarsal part. In the presence of additional lower eyelid laxity, particularly in the lateral canthal tendon, this procedure can be combined with a lateral tarsal strip procedure to tighten and shorten the lower eyelid.
The Jones procedure needs more dissection in the lower lid and more detailed knowledge of the anatomy.
Cicatricial Entropion
This is due to scarring of the conjunctiva and tarsal plate with shortening of the posterior lamella. Any condition that causes contracture, like chemical burns, mechanical trauma, topical glaucoma medication, ocular cicatricial mucous membrane pemphigoid and others, can induce scarring. It occurs commonly in upper and lower eyelids.
The choice of surgical procedures to correct lower eyelid cicatricial entropion is dictated by the severity of the entropion and the retraction and by the underlying cause. In ocular cicatricial pemphigoid, surgery should be confined to the anterior lamella whenever possible to avoid exacerbating the conjunctival disease. A retractor tightening procedure like the Jones procedure (see above) would be the method of choice.
Circumscribed conjunctival scars can be excised and corrected with a Z-plasty. Moderate degrees of cicatricial entropion with a minor degree of lid retraction can be managed with a tarsal fracture procedure. A horizontal incision is made through the whole length of the tarsus just below its centre down to the orbicularis muscle. Three double-armed 5-0 Vicryl sutures are passed from the lower fragment just below the incision and out through the skin immediately below the lash line. The sutures are tied to produce a mild overcorrection and removed after 2 weeks.
In severe cicatricial lower lid entropion with more severe degree of lid retraction, a posterior lamellar graft is indicated. The tarsoconjunctiva is lengthened with a graft, which is inserted near the lid margin to allow eversión. A piece of full-thickness buccal mucosa, tarsal plate, hard palate, ear cartilage or donor sclera is sutured with running 6-0 Vicryl sutures between the superior and inferior fragment of the horizontally divided lower tarsal plate. The lid margin is hold everted and the graft firmly apposed to its bed with everting sutures passed through the graft and tied on the skin just below the lashes.
Acute Spastic Entropion
Topical therapy of the underlying cause of ocular irritation may reverse the eyelid malposition. If this is not the case, a permanent entropion with usually involutional components may ensue, which will require surgical intervention according to the guidelines given before.
Upper Eyelid Entropion
Upper eyelid entropion is an eyelid malposition in which the upper eyelid margin is turned inwards against the globe. It can be responsible for severe OSD and ocular morbidity. It is relatively uncommon in the northern hemisphere in contrast to a number of countries in more arid areas of the world, where trachoma is endemic.
The condition can be congenital, which is rather rare, but is mainly caused by cicatricial changes of the posterior upper eyelid lamella. Any trauma, either mechanical or chemical, and infection to the conjunctiva can cause an upper eyelid entropion. Worldwide, trachoma is the most common cause of this upper eyelid malposition, other causes are listed in table. In addition to taking a careful history, a complete ocular examination with eversión of the posterior lamella and the superior fornix is essential to determine the etiology.
Upper eyelid trachoma may be further classified according to its severity as mild, moderate or severe. This is essential for choosing the most appropriate surgical procedure. However, first it is important to establish the diagnosis of upper eyelid entropion and differentiate this from simple trichiasis. This helps to avoid unnecessary and often useless epilation efforts.
Therapy
Anterior Lamellar Repositioning
This procedure is indicated in mild to moderate forms of upper eyelid entropion. It is easy to perform, safe and corrects the majority of upper lid entropia in the northern hemisphere [Hintschich, 1997]. The surgery divides the anterior from the posterior lamella of the upper eyelid, repositions the anterior lamella superiorly and sutures it to the tarsal plate at a higher level. This is often combined with a lid split at the grey line of the lid margin, which enhances the everting effect to the lid margin. This procedure requires a stable upper tarsal plate.
The superior tarsal plate is completely freed from the overlying orbicularis muscle down to the roots of the lashes through a skin crease incision. The entire length of the lid margin is split in the grey line, just anteriorly to the orifices of the meibomian glands, to a depth of 1-2 mm. Five to six 6-0 double-armed Vicryl sutures are anchored in the upper third of the anterior tarsal plate and then passed out through orbicularis and skin, just above the lash line. By closing these sutures, the anterior lamella is lifted and the lash-bearing part of the lid margin is everted. The split is allowed to granulate and the sutures can be left for spontaneous resorption.
In more severe forms of upper eyelid entropion a tarsal wedge resection or a rotation of the terminal tarsus can be performed. In cases of post-traumatic upper eyelid entropion, particularly after severe burns, the tarsal plate tends to be thin and unstable. This situation is often combined with upper lid retraction, conjunctival scarring and an upper fornix shortening. Under such conditions, none of the aforementioned techniques are applicable. A posterior lamellar graft is then indicated to stabilize and lengthen the upper eyelid. An autologous graft is put between the upper eyelid margin or the remnant of the tarsal plate and the recessed upper lid retractors.
A graft from the hard palate is favorable because it combines some stiffness with mucous membrane lining and is ideal for this kind of upper eyelid correction. Sutures and knots always should be covered by tissue to avoid corneal damage. Any aberrant or misdirected lashes and lid margin malpositions can be corrected at the same time, if necessary, by a full-thickness wedge excision.
It is important to correct cicatricial upper eyelid entropium before starting with any visual rehabilitative procedures, such as keratoplasty. Otherwise the continuing mechanical stress to the ocular surface caused by the lid malposition will jeopardize the result of any of these procedures. In consequence, one might be forced to perform lid surgery earlier than 6 months after the trauma in order to prevent ongoing damage to the ocular surface, although this can be associated with a higher failure rate of the surgery. Usually one waits for at least 6 months until healing and scarring is completed before corrective and reconstructive procedures are performed.
Ectropion
Lower eyelid ectropion is an eyelid malposition in which the lower eyelid margin is turned away from the globe. This condition can be classified into five categories according to the underlying etiology: (1) congenital ectropion and (2) acquired ectropion: (a) involutional ectropion; (b) cicatricial ectropion; (c) paralytic ectropion, and (d) mechanical ectropion.
Any severe ectropion with secondary lagophthalmos cannot only cause continuing epihora, but also OSD with exposure keratopathy and finally corneal ulceration. For therapy, it is important to be able to classify the actual type of ectropion so that the correct management is chosen based on the underlying cause. However, more than one etiological factor in one individual patient may be present, e.g. ongoing epiphora in a neglected involutional ectropion may lead to secondary cicatricial changes in the skin. This induces a vicious circle, which is increasingly difficult to reverse the longer the surgery is delayed. One should always look for cicatricial changes in the skin - either a general tightness, which is accentuated by asking the patient to look up and open the mouth, or a linear scar. Failure to recognize a cicatricial component is a common cause of surgical failure. Horizontal lid laxity and lateral or medial tendon weakness is assessed as for involutional entropion. Lower eyelid ectropion in facial nerve palsy mostly is associated with other abnormalities of facial nerve function, e.g. inability to lift the forehead or other signs of facial muscular weakness.
Congenital Ectropion
The majority of patients with congenital ectropion suffer from cicatricial ectropion due to a generalized shortage of the periorbital skin. Singular congenital ectropion is rare; it is mainly associated with additional abnormalities as in blepharophimosis syndrome, Down syndrome or ichthyosis. A congenital facial palsy like in a Moebius syndrome causes a paralytic ectropion.
Patients with shortage of skin require full-thickness skin grafting (see below). This surgery is purely functional and the aesthetic results are less favorable in comparison to the results in adults. However, in cases of severe cicatricial ectropion with lagophthalmos causing keratopathy in young children, skin grafting procedures should not be delayed to prevent them from sight-threatening complications. Tarsorrhaphies never work sufficiently in these cases and will only complicate the situation and delay a definite correction.
Acquired Ectropion
Involutional Ectropion
The most common type of ectropion is the involutional ectropion with its variety of involutional tissue changes including horizontal lid laxity, weakness of the retractors and a dissociation between the lamellae. The surgical procedure should address the underlying etiological factors, as mentioned above. In general, the surgery of an involutional ectropion, particularly of the medial eyelid with punctual eversión, medial tendon laxity, chronic conjunctival exposure and lacrimal pump insufficiency is difficult and the results often are less favorable compared to other lid malformations.
The treatment of involutional lower eyelid ectropion is to correct the lower lid laxity by shortening the lid in the area of maximum laxity. This can be carried out centrally or laterally, under a blepharoplasty flap which allows excess skin and fat to be removed for improved aesthetics, at the lateral canthus or medially just lateral to the punctum. Inverting sutures can support the correction of an everted lid margin. Inversion can be further helped if the posterior lamella of the lid is shortened and the lower lid retractors tightened with the excision of a diamond of tarsoconjunctiva and lower lid retractor plication. If the lid laxity is maximum in the medial canthal tendon this can be tightened with a medial canthal suture or a medial canthal full-thickness resection. Such a medial canthal resection involves cutting the inferior canaliculus that can be marsupialized into the conjunctival sac without necessarily causing epiphora.
Full-Thickness Wedge Excision
A full-thickness pentagon of lid is resected from the area of maximum lid laxity. If there is general lid laxity, the excision is performed in the lateral third of the lower eyelid. The amount of excision, which is necessary for correction, is assessed by overlapping the medial and the lateral portion of the lid gently. The lid transsection has to be perpendicular to the lid margin. Once the pentagon is excised, small vessels are cauterized, and the lid defect is repaired.
Lid Margin Repair
Two or three 6-0 Vicryl sutures on a half circle needle are passed with a horizontal partial-thickness bite into the tarsal plate of one wound edge and then into the tarsal plate of the other wound edge at the corresponding height entering from its conjunctival side. Before closing the sutures, the alignment of the lid margin is checked. Then a silk suture is passed through the grey line and in line with it and closed, leaving its ends long. An additional silk suture is passed in the lash line, some more in the skin to close it. The long ends of the grey line suture are caught and knotted with the skin sutures to prevent the grey line suture from rubbing against the globe. The silk sutures can be removed after 1 week.
Lazy T Procedure
This procedure corrects a medial ectropion with horizontal lid laxity. A medial full-thickness lid resection is combined with an excision of a diamond-shaped part of conjunctiva and subconjunctival tissue, which is closed with an inverting suture. The diamond excision is carried out in the conjunctiva immediately below the lower punctum. One needle of a double-armed 6-0 absorbable suture is passed through the superior apex of the diamond, the other through the conjunctiva below its inferior apex. With this needle, parts of the lower lid retractors are picked up, which are best found lateral to the diamond. Both needles are passed through orbicularis and skin and tied anteriorly. This suture not only closes the diamond excision, but also increases the inversion of the punctum, particularly on down-gaze.
Lateral Tarsal Strip Procedure
This procedure is an excellent method to correct any horizontal lower lid laxity and can be used for both entropion and ectropion repair [Anderson and Gordy, 1979]. It can be combined either with inverting or everting procedures, depending on the underlying pathology. If there is significant medial canthal laxity and the procedure would cause an unacceptable lateral displacement of the punctum, a lateral tarsal strip procedure should not be used (or only in combination with a medial tendon reinforcement).
The principle of this procedure is based on a (re)attachment of the lateral part of the tarsal plate to the periorbital tissue adjacent to the bony orbital rim inside the zygomatic arch. To attain a good result it is mandatory to free the lateral part of the tarsal plate from any epithelial tissues and to suture it as posterior as possible inside the orbital rim. This is necessary to firstly avoid the complication of inclusion cysts and secondly to reach the best alignment of the lid margin to the globe.
Usually monofile non-absorbable sutures, like 6-0 Prolene, are used, but long-acting absorbable sutures, like 5-0 Vicryl, also will work. The lateral canthal area and the bone is approached by an approximately 10 mm horizontal skin incision starting from the lateral canthus. The lower limb of the lateral canthal tendon is cut. The lateral part of the lower lid tarsal plate is completely denuded by removing the lid margin with all lash roots, the orbicularis muscle and the conjunctiva. In cases of a stretched tarsal plate causing marked laxity, a piece of tarsus can be resected. If the tarsal plate is too short to form a lateral canthal tendon, which reaches the periorbit, a periosteal flap can be formed. Such a flap can easily be dissected by incising the periosteum at the outer surface of the zygomatic bone, leaving the junction in the inner part of the arch intact. The lateral tarsal strip is sutured with a double-armed suture to either the periorbital tissue or the periosteal flap. The lateral canthus is restored with a hidden simple suture and the skin is closed.
Cicatricial Ectropion
Cicatricial ectropion is due to a shortage of skin. This can be either congenital or acquired. If the skin shortage is local it can be corrected with a Z-plasty and if it is general it should be corrected by the addition of skin either as a flap or a free graft. The treatment of cicatricial ectropion with tarsorrhaphy is useless and a waste of time. However, any additional lid laxity can be corrected with a lid shortening procedure.
Skin Grafting. In the periorbital area, full-thickness grafts are preferable to split-thickness grafts. Suitable donor sites are the upper eyelid (ipsi- or contralateral), the pre-or retroauricular site, and the inner side of the upper arm or the supra-clavicular fossa.
The recipient site must be prepared carefully, any subcutaneous scar tissue causing traction be excised and bleeding stopped. Traction sutures help to keep the bed stretched. The graft should be as thin as possible and not oversized, but just fitted into the defect to prevent it from developing a wrinkled surface. The graft should be left undisturbed for at least 2-3 days with a moist pressure dressing applying continuous pressure onto the stretched graft.
Paralytic Ectropion
A paralytic ectropion is caused by a seventh nerve palsy and due to a lack of normal innervation of the orbicularis muscle. Failure of normal lid closure with lower lid laxity and ectropion, upper eyelid retraction and brow ptosis are the clinical signs.
Lagophthalmos can cause severe OSD with corneal epithelial defects. The risk of significant morbidity is higher in patients with peripheral seventh nerve palsy, severe lagophthalmos, missing Bell's phenomenon and reduced corneal sensibility. In these patients, if no early spontaneous restoration of facial nerve function can be observed, an early surgical intervention to improve the lid closure is indicated. This can be either a temporary tarsorrhaphy or a botulinus toxin injection. The lower eyelid primarily requires support to hold the lid up against gravity. Lower eyelid ectropion repair is best performed by a lateral tarsal strip procedure. This can by combined with a medial canthoplasty (Otis-Lee procedure) [Lee, 1951]. With this simple procedure the upper and lower lid margins medial to the lacrimal puncta are sutured together permanently. This reduces the interpalpebral distance at the medial canthus and brings the lacrimal puncta into the tear film. Lid laxity can be corrected medially with medial can-thai sutures or in long-standing cases with a medial canthal resection.
Before putting weights into the upper eyelid, it is important to correct any lower lid ectropion and upper eyelid retraction first. Lid loading should be the last and not the first surgical procedure!
Floppy Eyelid Syndrome
Upper eyelid ectropion can be part of the 'floppy eyelid syndrome' [Culbertson and Ostler, 1981] which includes easily everted upper eyelids, chronic papillary conjunctivitis, and non-specific irritation. The typical patient with FES is male and obese with symptoms of foreign body sensation, morning tearing, mattering and redness, photophobia, and awakening with an everted eyelid. 70% of the patients present corneal involvement. The pathophysiology of FES is probably multifactorial with systemic mechanisms (obstructive sleep apnea) and mechanical mechanisms (sleeping preference).
Regardless of the cause, most patients benefit from surgical eyelid tightening after conservative measures such as shields, lubrication, and weight loss have failed to provide relief. To date, the literature on the surgical treatment of FES recommends pentagonal wedge resection beginning at the lateral third of the eyelid or a lateral tarsal strip procedure. These simple approaches are extremely helpful in treating OSD in such patients [Culbertson and Tseng, 1994]. In addition, a number of modifications have been described recently -including medial upper eyelid shortening - for which the reader is directed to the primary literature [Moore et al, 1996; Periman and Sires, 2002; Valenzuela and Sullivan, 2005].
