The main problems I see in relation to poor repair of the eyelids relate to excessive debridement of apparently devitalised tissue at the time of primary repair. Minimal surgical debridement is the rule in facial and lid lacerations due to the superior healing characteristics of wounds in this area, arising from its abundant blood supply (1). Even apparently devitalised tissues may regain perfusion when anatomical relationships have been restored.
The second main problem which I see is poor alignment of the eyelid margin, producing a notched or stepped appearance. In repairing the lids, the tarsal plates must be accurately aligned to prevent eyelid deformity, and the eyelid margins must be smooth to prevent corneal damage.
In severe trauma, delay in eyelid repair is acceptable while more life-threatening injuries are dealt with, but it is important to ensure that the globe is protected from pressure until penetrating injury is excluded, and that the cornea is protected from dehydration until the eyelids can be repaired.
The method which I use to carry out secondary repair of the eyelid are identical to that which I would use for primary of closure of eyelid lacerations
1. I place a lid guard to protect the globe. 2. I align the grey line with 6/0 virgin silk, leaving the ends long and placing the suture under light traction to bring the tarsal plates into alignment. 3. I close the tarsal plate with 5/0 vicryl. These are structural sutures and I test the bites for adequacy and place them just shallow of the conjunctival plane to avoid rubbing on the cornea. 4. I close skin and orbicularis with 6/0 silk or nylon. .5. I release the grey line suture from traction and tie it down away from the cornea with the top skin suture. 6. I remove skin sutures at day 5. 7. I remove the grey line suture at day 10.
The third problem which I see is scarring, and I manage this as follows:
Lower eyelid cicatricial ectropion is present when the lower lid margin cannot be pushed up to reach the margin of the upper lid with the eye open. In less severe degrees the lower lid margin cannot be pushed up to reach the margin of the upper lid with the eye open and the the mouth open. The treatment of cicatricial ectropion depends on whether it is due to a vertical scar or to combined horizontal and vertical skin shortage. Z-plasty is used to treat vertical lid scars. Skin grafting is used to treat combined horizontal and vertical skin shortage Suitable donor sites include the pre-auricular skin, the post-auricular skin and the supraclavicular fossa. The lid is placed on upward traction. External bolsters are fashioned from gauze to match the graft and tied in place with the long ended anchoring sutures. Pressure dressing are applied and left in place for 48 hours.
Dermis- fat grafting or fat pearl grafts are useful in supplying subcutaneous bulk to scarred areas in the lower lid /cheek and in the upper lid sulcus; the fat cells inhibit further scarring and provide a more natural antifibrotic effect than antimetabolites. Dermofat grafts can be obtained from the periumbilical and groin regions of the abdomen or from the buttock.
The fourth commonest problem which I see are medial canthal lacerations. These are commonly seen in dog bites. Canalicular lacerations often coexist. If only the anterior limb is damaged, then this can be approximated using 6/0 ethibond. If the posterior limb is involved in the injury, then repair of the anterior limb alone will result in eversion of the medial end of the eyelid. The medial end of the tarsal plate should be sutured to the periosteum of the posterior lacrimal crest provided that an adequate fixation point is present. If no adequate fixation point can be found then a miniplate or transnasal wiring technique can be used.
The fifth commonest problem which I see are canalicular lacerations. Under normal circumstances, 30% of the tear drainage is via the upper and 70% via the lower canaliculus. The primary repair of these is frought with controversy. Epiphora is rare unless both canaliculi are involved, and isolated injury of either the upper or the lower canaliculus is likely to be compensated for by the other canaliculus ( 4, 5, 6, 7 ). It follows that no method of repair which compromises the function of the undamaged canaliculus should be contemplated. Bicanalicular lacerations should be repaired using the pigtail probe technique, but the patient must be warned that post operative stenosis is likely and that this may subsequently require conjunctivo-DCR with placement of a Pyrex tube. Single canalicular lacerations can be dealt with safely by accurately repairing the eyelid, ensuring apposition to the globe, and marsupialising the distal segment of the transected canaliculus in the wound using a three-snip procedure. The marsupialised area can be held open by placing 8/0 vicryl sutures. Common canalicular lacerations are dealt with by carrying out a primary canaliculo-DCR with intubation (5).
References (1) Mustarde J. Repair and reconstruction in the orbital region: a practical guide. Churchill Livingstone, Edinburgh, 1980.
(2) Mansor MA, Moore EE, Moore FA, Whitehill TA. Validating the selective management of penetrating neck wounds. Am.J. Surg; 162: 517-521.
(3) Dryden RN, Beyer TL. Repair of canalicular lacerations with silicone intubation. In: Levine MR. Manual of oculoplastic surgery. Churchill Livingstone, New York, 1988.
(4) Collin JRO. Repair of eyelid injuries. In: Manual of systematic eyelid surgery. Churchill Livingstone, Edinburgh, 1989.
(5) Welham RAN. The lacrimal apparatus. In: Miller S. Clinical ophthalmology. Wright, London, 1987.
(6) Saunders DH. The effectiveness of the pigtail probe method of repairing canalicular lacerations. Ophthalm. Surg. 1978; 9: 33-39.
(7) Canavan M, Archer DB. Long term review of injuries to the lacrimal apparatus. Ophthalm. Soc. U.K. 1979; 63: 549-555.
ORBITAL TRAUMA
Orbital fractures are frequently associated with injury to the globe, canthal tendons and lacrimal apparatus. The optic nerve, infraorbital nerve and nerves to the extraocular muscles may be involved in apical fractures.
Internal (blowout) fractures
The orbital contents are separated from the paranasal sinuses by thin plates of bone. Force transmitted to the eye causes a shockwave of increased intraorbital pressure, which results in fracture at the weakest points, namely the lamina papyracea of the ethmoid bone and the posteromedial orbital floor. The clinical features are periorbital haematoma, conjunctival haematoma, axial displacement and vertical displacement of the globe, abnormal eye movements and infraorbital nerve anaesthesia. Axial displacement usually takes the form of enophthalmos due to prolapse of orbital contents. Normally, Lockwood's ligament prevents globe hypotopia, but this may occur in large floor defects due to rupture or stretching of the ligament. Exophthalmos may occasionally be seen, due to orbital haemorrhage.
A variety of mechanisms are invoked to explain the motility abnormalities, including entrapment of muscle or connective tissue septa in the fracture site, haemorrhage into the posteroinferior fat, contusion injury to the muscle or intramuscular haematoma, nerve injury, or Volkmann's ischaemic contracture.
Investigations
Plain X-rays show a fracture line and opacification of the roof of the antrum (hanging-drop sign). This may not always be due to actual prolapse of orbital contents as it can also be produced by haemorrhage or oedema in the sinus mucosa. CT scans are more sensitive in fracture detection and can show its size. This may be of some use in predicting outcome and defining those cases which will benefit from early surgical intervention.
Complications
The rate of ocular injury is quoted at between 15-30%. This varies from inconsequential signs such as subconjunctival haemorrhage to serious injuries with varying degrees of long-term visual dysfunction such as hyphaema, angle recession, dislocated lens, cataract, vitreous haemorrhage, commotio retinae, choroidal rupture, macular scarring or even rupture of the globe. Hypo-aesthesia of the infraorbital nerve has a tendency to spontaneous recovery due to axonal regrowth. Orbital emphysema is due to air from the paranasal sinuses being forced into the soft tissues at the time of injury or subsequently. It resolves spontaneously but may be complicated by infection or, rarely, by optic nerve compression.
Orbital cellulitis may occur, particularly when a blowout occurs in the setting of sinusitis. The normal sinus is a sterile environment and the role of antibiotic prophylaxis is controversial.
Treatment Any associated injury to the globe must be dealt with prior to bony manipulations. Extreme controversy exists as to the selection of cases for early surgical repair and its timing. A sensible approach is to re-assess the patient at two weeks post-injury and operate on those patients with cosmetically unacceptable enophthalmos or non-resolving, handicapping diplopia of a type which is likely to respond to floor repair, namely that which is due to restriction rather than paresis - evinced by either a positive forced duction test or hard CT evidence of tissue entrapment. Orbital floor repair is carried out by a transconjunctival or subciliary dissecion to the orbital rim, elevation of the periosteum of the orbital floor, reduction of prolapsed orbital tissues, and repair of the bony defect, usually with non-autogenous materials such as a silastic sheet, which is wired in place to the orbital rim. Care must be taken not to damage the optic nerve during repair and the visual function must be closely monitored post-operatively.
Prevention of amblyopia
In orbital trauma in children it is important to take steps to prevent amblyopia by measures aimed at reducing swelling rapidly (ice packs, prompt treatment of infection) and occluding the fellow eye if necessary. While it would be acceptable to delay the repair of a traumatic ptosis in an adult, this would carry the risk of amblyopia in a child and a temporary brow suspension should be carried out urgently if necessary.
