|Year : 1984 | Volume
| Issue : 5 | Page : 299-301
Management of anterior segment perforating ocular injuries involving lens and vitreous
Department of Ophthalmology, West Virginia University, Motgantown West Virginia, USA
V K Raju
Department of Ophthalmology, P.O. Box 6302. West Virginia University, Morgantown, WV 26506
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Raju V K. Management of anterior segment perforating ocular injuries involving lens and vitreous. Indian J Ophthalmol 1984;32:299-301
The use of vitrectomy instrumentation during primary surgical management of anterior segment injuries minimizes many post traumatic complications and multiple operations. Complications needing multiple reoperations include after cataract membranes, anterior and posterior synechiae, adherent leukoma, eccentric pupil, secondary glaucoma, and retinal detachment.
Instrumentation and surgical techniques primarily developed for pars plana vitreous surgery provide new capabilities in the management of perforating ' eye injuries., Severe perforating injuries often have a poor prognosis for both recovery of visual function and salvage of the eye. The initial mechanical damage may be complicated by secondary changes that can result in total loss of vision and atrophy of the globe. Therefore initial surgery should be directed toward optimal repair of the perforating wound, correction of damage caused by the injury and prevention of secondary complications.
Preoperative evaluation: preoperative sensory evaluation and physical examination are important to determine the extent of injury and damage to the eye. But detailed examination of eyes with open corneal and/or scleral wounds often cannot be safely performed. Therefore evaluation and surgical repair are best performed under general anesthesia. Complete akinesia, anesthesia, reduced intraocular and orbital pressure are obvious advantages of well administered general anesthesia. The eye should be protected with a metal shield until the patient is intubated in the operating room. This prevents further damage from external pressure inadvertently applied by the patient, during x-ray examination, or during induction of general anesthesia.
Surgical principles and techniques: Modem microsurgical instruments combining infusion, cutting and suction features help in the early management of a severely injured eye and the damaged lens, blood and vitreous may be removed from the anterior chamber. Once the damaged vitreous is removed it cannot later contract or serve as a matrix for fibrous tissue growth. Intraocular fibrosis and vitreous traction are the most destructive of the secondary complications.
The prognosis for an eye damaged by, severe trauma is also dependent on method of management. Conventional (non-radical) surgical techniques and antibiotic therapy are effective in managing manyperforating injuries involving the anterior segment and small magnetic intraocular foreign bodies in the posterior segment. However, injuries having a poor prognosis when managed by conventional means include 1) eyes with admixed lens material and vitreous, 2) vitreous hemorrhage and retinal detachment, 3) non-magnetic intraocular foreign bodies, 4) lacerations posterior to the ora serrata and 5) double perforations. These are injuries often complicated by intraocular fibrosis, cyclitic membrane formation with hypotony and shrinkage of the globe.
Intraocular fibrosis is especially common following perforating injuries in young, but may occur at any age and may be associated with faulty or delayed wound closure. Fibrovascular tissue can fill the anterior chamber or cover the ciliary processes and grow across the anterior vitreous cavity causing ciliary body detachment and phthisis bulbi. Progressive vitreous traction often occurs when the vitreous gel has been penetrated or when vitreous is caught in a scleral wound. This can result in traction on the vitreous base 180° away, causing retinal breaks and detachment. It is well known that complications of vitreous loss correlate more with vitreous incarceration in the wound than with the amount lost.
The complications of intraocular fibrosis and vitreous traction begin soon after a perforating injury. Intraocular fibrosis may be caused either by invasion of fibrovascular tissue through the wound, or inflammatory and damaged cells within the eye that undergo metaplasia becoming fibroblasts secreting extracellular collagen. Reparative fibrovascular proliferation begins within hours after a perforating injury. This process which forms the scar that seals the wound, originates primarily from the adjacent episcleral tissue and from inflammatory cells that infiltrate the wound edges. But, the fibrovascular tissue may extend within the eye by growing along contiguous surfaces. Intraocular invasion by fibrovascular tissue may be extensive in 1) the young, 2) eyes with poorly opposed wound edges, 3) when vitreous or other structures are adherent to the wound, and 4) when persistent intraocular inflammation is present.
Seleral wounds extending posterior to the ora serrata associated with vitreous loss are closed with sutures, the surrounding area treated by diathermy or cryotherapy and a local scleral buckle is placed beneath the wound. Intraocular foreign bodies should be extracted, appropriate cultures obtained, and the patient treated with systemic antibiotic therapy to prevent infection.
The objectives of primary radical surgery in severely traumatized eyes are to prevent secondary complications. By providing a deep anterior chamber, and excising the damaged lens and formed vitreous, multiple operations are avoided and early visual rehabilitation made possible.
Surgical technique: The surgical technique for eyes with a perforating wound begins with meticulous identification of corneal and scleral lacerations, the extent of each wound determined by reflecting adjacent conjunctiva. Bleeding during the surgery usually can be controlled by elevating the infusion bottle and increasing the intraocular pressure although intraocular coagulation may be applied. In most patients, satisfactory closure of the wound can be achieved which permits the performance of lensectomy and vitrectomy via the surgical limbus at the time of primary repair. The anterior chamber is swept with a fine vitreous spatula to be certain that no vitreous or iris strands are caught in the posterior lips of the wound.
If the surgeon does not have the vitrectomy instrumentation removal of material by the sponge technique, repeated irrigation and aspiration with a 20 gauge needle may be performed. At the end, adequate restoration of the anterior chamber by injection of air into it may be the simplest and most effective technique for avoiding adhesions.
Prognosis: The prognosis for an injured eye is largely dependent on the severity of the injury and the extent of initial mechanical damage. Corneoscleral lacerations of greater than 8mm, injuries with severe prolapse of intraocular contents, double perforations, retained intraocular foreign bodies and extensive intraocular damage carry a poor prognosis. The association between initial ocular damage and the possibility of saving the eye is seen in the incidence of enucleation following perforating injuries, which varies from 7% for small corneal lacerations to 50 to 70% for severe perforations with vitreous loss.
In my series of 24 cases (1976-1982), 50% resulted in ultimate enucleation. In these, the initial damage was extensive with vitreous involvement. In 30% of cases, the final visual acuity was 20/70 or better. In 20%, visual acuity was count fingers to 20/200.
Several authors have found that vitreous surgery techniques were often ineffective when intraocular fibrosis complicated perforating injuries resulting in dense vitreous organization and complicated retinal detachment.
| Summary|| |
Ocular injuries are one of the leading causes of blindness throughout the world. Nearly 1/3 of the eyes lost in the first decade of life are attributable to trauma. Severe injuries of the globe are often associated with damage to multiple ocular tissues including the cornea, sclera, lens, vitreous, uvea and retina. The combination of initial damage and secondary complications can, and often does, result in loss of the eye. The current surgical management should be directed toward optimal repair during the first operation, correction of damage caused by the injury and prevention of secondary complications.
Prevention: The adage "an ounce of prevention is worth a pound of cure" is most apt for ocular trauma. Prevention of devastating ocular injuries through stronger educational campaign and mandatory use of safety glasses in hazardous occupations shows a foresight in protecting vision that most up-todate and heroic surgical efforts to save sight cannot match.
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