Neglected ectropion leads to epiphora and secondary cicatricial changes in the skin. A vicious circle is set up which is increasingly difficult to reverse the longer surgery is delayed.
Cicatricial – generalised
Look for cicatricial changes in the skin – either a generalised tightness, accentuated by asking the patient to look up and open the mouth, or a linear scar ( Sect. B ).
Assess the lid for horizontal laxity and other involutional changes ( Sect. A ).
The main factor in the pathogenesis of involutional ectropion is horizontal lower eyelid laxity.
Choice of operation
The lower lid may be tightened by shortening it horizontally. This is achieved with full-thickness lid excision ( 7.1 ) or with a lateral tarsal strip (lateral canthal sling) ( 7.2 ) or Bick procedure ( 7.3 ). Ectropion which is mainly medial may be corrected with either of these procedures combined with excision of a medial diamond of conjunctiva ( 7.4 , 7.5 ). If the medial canthal tendon is lax, aim to stabilise it by attachment to the posterior lacrimal crest ( 7.7 , 7.8 ).
If there is a marked excess of skin in the lower lid this may be excised at the time of the ectropion correction with a Kuhnt-Szymanowski procedure ( 7.6 ).
Horizontal lid shortening
Plan to excise a pentagon of full-thickness eyelid (see 14.1 ) where the ectropion is most marked. If there is significant laxity of the medial canthal tendon this must be corrected first, before this or any other procedure which tightens the lid.
Having made the first incision at right angles to the lid margin at the chosen site, overlap the cut edges to estimate the horizontal length of lid to be excised (as in Fig. 7.5a ). Aim at good apposition of the lid to the eye but avoid undue tension across the closure.
If the lower lid retractors are lax or detached tightening the lid may cause the tarsal plate to evert completely. This can be corrected by reattaching the lower lid retractors to the inferior border of the tarsal plate, or tucking them, with a Jones procedure (see 6.4 ).
Lateral tarsal strip (canthal sling) ( )
Pull the lower lid medially and slightly down to put the lower limb of the lateral canthal tendon on stretch. It is directed posteriorly and laterally from the tarsal plate to the lateral orbital rim (see also 14.4c , 14.6c ). Keeping the tendon on stretch, spread sharp-pointed scissors between the tendon and the conjunctiva (lying posterior to it) to open this plane. Repeat this between the tendon and the orbicularis muscle (lying anterior to it) to open this plane. This exposes the lower limb of the lateral canthal tendon which can now be felt as a tight band between the orbicularis muscle anteriorly and the conjunctiva posteriorly, just inferior to the lower edge of the incision
With the tendon still on stretch, cut it laterally, against the lateral orbital rim. Take care to preserve the upper limb of the tendon which can be identified in the same way close to the upper edge of the incision. Pull the cut tendon laterally and superiorly to check its mobility. It should be possible to lift the lateral end of the lower lid upwards with no resistance. If there is resistance, this is probably due to the septum as it attaches along the lower lateral part of the orbital rim. Keeping the septum on stretch, pass blunt-ended scissors down along the lower lateral part of the orbital rim and cut the attachment of the septum until the lid moves freely laterally and superiorly.
Pull the lower lid laterally under moderate tension to assess the position of the new lateral canthus on the lower lid. This will be at the point where the upper lid canthus meets the stretched lower lid margin. Mark this point. Do not overtighten the lid, especially if the eye is proptosed. This would cause lower lid retraction.
The new lateral canthal tendon needs to be exposed further by removing the skin, lid margina and conjunctiva. To do this, undermine the skin, then cut it close to the lashes as far as the mark on the lid margin; excise the superficial tissues of the lid margin for the same distance. The excess conjunctiva is difficult to excise – cauterising its surface is equally effective.
Make a small cut of about 6 mm, from lateral to medial, and about 6 mm inferior to the upper border of the new canthal tendon, to elongate it. This creates the lateral tarsal strip. Pass a double-armed 4/0 or 5/0 suture through the lateral tarsal strip. The suture may be nonabsorbable or absorbable.
Pass both arms of the suture through the periosteum just within the lateral orbital rim. The lateral canthus should be positioned 2 to 3 mm higher than the medial canthus. The lower lid should be under sufficient tension to correct horizontal laxity. As noted previously, care is needed if the eye is proptosed.
Now pass the needles through the periosteum overlying the anterior surface of the lateral orbital rim more laterally. Tie the suture. This stabilises the lateral canthus and ensures that the suture knot is placed well laterally, deep to the orbicularis muscle. This reduces the risk of complications from the knot.
Granuloma formation may follow the use of a braided suture to secure the lateral tarsal strip. The canthus may be set too high and the level should be carefully checked at operation. Lid retraction in the presence of a proptosed eye can be avoided by reducing the horizontal tension in the lid when the tarsal strip is secured.
Bick lid tightening ( Fig. 7.3 )
The Bick procedure shortens the lower lid laterally adjacent to the lateral canthus. The lid is reattached to the lower limb of the lateral canthal tendon or the periosteum of the lateral orbital rim. In this modification of the procedure the lid shortening is performed beneath a skin flap.
Excision of a medial conjunctival diamond
Join the cuts to form a diamond of conjunctiva and excise the diamond together with some subconjunctival tissue. This exposes, and may include, part of the lower lid retractors which may appear as a white sheet in the depths of the wound. If the medial ectropion extends laterally from the punctum, extend the diamond laterally, immediately inferior to the lower tarsal border, as shown. The white line shows the position of the final incision if there has been no extension laterally along the inferior fornix.
Close the conjunctiva and underlying lower lid retractors with two or three 6/0 or 7/0 absorbable sutures. This tightens the posterior lamella of the lid and inverts the punctum. If the punctum is stenosed perform a ‘one snip’ to open it. To do this make a vertical incision with sharp pointed scissors in the posterior wall of the punctum and vertical part of the canaliculus.
Local scarring and contraction of the conjunctiva often follow the diamond excision. The punctum may be inadequately inverted. Excise further conjunctiva when healed or consider simple retropunctal cautery to augment the effect.
Horizontal shortening medially with excision of a medial conjunctival diamond (‘Lazy- T ’)
This procedure is effective in correcting medial ectropion. However, it not infrequently results in some distortion of the lid margin immediately lateral to the lid shortening. A lateral tarsal strip ( 7.2 ), or Bick procedure ( 7.3 ), with excision of a medial conjunctival diamond ( 7.4 ) is usually preferred.
Make an incision through the full thickness of the lower lid 4 mm lateral to the punctum. Overlap the cut edges and excise the excess tissue as a pentagon (see 14.1 ).
Excise a horizontal diamond of conjunctiva. Leave 2 to 3 mm between the punctum and the superior edge of the diamond. Pass one needle of a double-armed 6/0 absorbable suture through the conjunctiva immediately below the punctum and then obliquely through the lid to the skin at a level about 5 mm lower. Pass the other needle through the conjunctiva and lower lid retractors at the opposite edge of the diamond, then obliquely through the lid to the skin just below the first needle. When this suture is tied the punctal ectropion will be corrected. Alternatively, close the diamond as described in 7.4d without full-thickness sutures passing out to the surface of the skin.
Persistent eversion of the punctum may be due to inadequate excision of posterior lamellar tissue or to distortion of the lid margin at the site of direct closure. Once the lid has healed with a persistently everted punctum retropunctal cautery is often effective.