Penetrating Wounds of the Eyeball

Of all patients treated in hospital for trauma of the organ of vision, penetrating wounds constitute 35-80% and are considered to be severe injuries to the eye.

Depending on localization of the wound there are corneal, lim­bic, corneal-scleral and scleral wounds. Wounds may be of differ­ent shape and size: small — up to 3 mm; middle — 4-6 mm; big — over 6 mm. According to the shape there are linear, irregular, lacerated, stab, stellate wounds, as well as wounds with tissue de­fects. Besides, they may be gaping and adapted when the wound edges touch tightly along the wound.

The penetrating wounds are often accompanied by lens damage (40%), prolapse or incarceration of the iris (30%), haemorrhage into the anterior chamber or the hyaloid body (about 20%), endoph-thamitis due to penetration of infection into the eye. Almost in one third of the patients penetrating wounds are accompanied by in­traocular foreign bodies. The course of the wound process is fre­quently complicated by several complications at once.

Absolute signs of the penetrating wound are gaping wound of the cornea or sclera, prolapse of the inner membranes of the eye, opening in the iris, foreign body inside the eye.

Besides absolute there is a number of doubtful (relative) signs of the penetrating wound: hypotonia (though it may be observed also after eye contusion), occurring due to outflow of the fluid from the anterior chamber, changed shape of the pupil (its protrusion towards fluid outflow). When the penetrating wound is in the sclera, the anterior chamber may become deep due to outflow of the vit­reous and displacement of the iris and lens backward.

In some cases diagnosis of the penetrating trauma of the wound becomes difficult. When the object is very sharp and small adhe­sion and sufficient adaptation of the wound edges come rather fast, the anterior chamber is restored and hypotension disappears. Di­agnosis of the penetrating sclera wounds is often complicated by concomitant injury of the conjuctiva, its oedema and haematoma.

The true signs of the perforating wound are foreign body be­hind the eye, inlet and outlet opening, sometimes exophthalmos be­cause of haemorrhage into retrobulbar fat.

Destruction of the eyeball is the most severe form of the pene­trating wound and does not require special diagnostic techniques. In such case all the ocular membranes are so damaged and loss of eye content is so significant that walls of the eyeball stick togeth­er and it loses its shape. Not infrequently destruction of the eye­ball is combined with injuries of the eyelids, orbit and surrounding tissues. In eye destruction it is impossible to save it, initial enucle­ation is indicated.

All patients with suspected penetrating wound of the eye are ur­gently conducted X-ray review roentgenography of the orbit. In re­vealing shadow of the foreign body it should be localized with the help of additional special methods of investigation. For this purpose we use method of roentgenolocalization by Comberg — Baltin which consists in using of aluminium prosthesis-indicator as a ring of 5 mm with curvature radius corresponding to sclera curvature with open­ing of 11 mm in the center. At a distance of 0.5 mm from the open­ing edge 4 lead points are pressed into the ring, located on the inter-perpendicular meridians. After epibulbar anesthesia this prosthesis-indicator is put on the eye so that lead markers correspond to the limbus for 12, 3, 6, and 9 hours. Two X-ray films are made in direct and side projections. The first film determines the meridian where the foreign body is located as well as its distance from anatomical axis of the eye. The second film helps to establish the distance from the foreign body to the limbus. Exact localization of the foreign body is calculated with the help of special measuring schemes and special tables. However, measuring schemes by the Comberg — Baltin's method are meant for a scheme eye. Therefore additional ultrason­ic investigation is necessary in the foreign body in the marginal zone, i.e. in ocular membranes or close to them. It helps to determine in­dividual size of the eye and define more exactly the localization of the foreign body as to the eye membrane, i.e. to determine whether it is inside or behind the eye. Skeleton-free roentgenography by Fogte is used to diagnose fine foreign bodies in the anterior part of the eye including nonmetallic ones (glass, stone).

In yawning wounds of the cornea when the application of Comberg — Baltin's prosthesis is risky, limbus can be marked by bismuth (roentgenocontrast) or the cornea center — by metallic probe.

More exact information about localization of the foreign body in the marginal zone (regarding the eye membranes) and multiple foreign bodies can be obtained by computed tomography. The mini­mum size of metal piece revealed by tomography is 0.2, 0.3 mm and a glass one is 0.5 mm. To find precise localization of the for­eign body on examination and during operation additional meth­ods are used, such as ultrasound and electronic localization, tran­sillumination and retrobulbar diaphonoseopy.

The first aid in penetrating wound must be given by any doc­tor. It is necessary to put disinfection drops into the conjunctival sac, apply binocular bandage. It is obligatory to introduce broad spectrum antibiotics, tetanus anatoxin 0.5 ml intramuscularly and if necessary antitetanus serum by Bezredko (according to the in­struction).

After rendering the first aid the patient should be immediately brought to specialized eye inpatient department, traumatic centre is preferable (eye traumatic centre). The patient must be transport­ed in a horizontal position.

Treatment of the penetrating eye wounds consists in surgical treatment of the eyeball wound, it must be done under microscope using microsurgical instruments. The main task of the ophthalmol­ogist is to achieve maximum restoration of anatomo-physiological interrelations of the eye structures and secure wound hermitiza-tion.

It is expedient to perform the earliest treatment of the penetrat­ing eye traumas which may be simple, combined or reconstructive. After local or general anesthesia foreign bodies, soiling the wound, are removed and the wound is irrigated with antibiotic solution. Wound hermitization is performed by continuous or interrupted sutures till complete adaptation of the wound edges. Kapron or nylon is used for this purpose: 10/0 — for the cornea wounds and 8/0 — for the sclera wounds. Sutures promote restoration of eye turgor and healing of the wound by primary tension. In the vast cornea wound of irregular shape with lacerated edge, when the su­ture can't provide reliable wound hermitization, fixing transplan­tation of the cornea in layers is performed additionally (by the meth­od of N. A. Puchkovska). In the cornea wound with tissue defect it is indicated to perform combined lamellar through keratoplasty with two grafts: tissue defect is closed by through graft which is fixed by 2-4 interrupted sutures and lamellar corneal graft is ap­plied above. It closes the damaged cornea surface completely and is fixed by sutures to the sclera at the lymbus.

In penetrating eye-ball wounds there is often iris prolapse into the wound, more rarely — lens mass and vitreous prolapse. Earli­er the prolapsed iris was always dissected in order to avoid infec­tion in the eye cavity. Lately therapeutic approach to these wounds has changed as follows: the first 1-2 days after the wound the pro­lapsed iris can be carefully adjusted by the spatula after prelimi­nary cleansing from soiling and irrigation with antibiotics. The cor­nea wound is fixed by suture.

Development of microsurgical technique, instruments, modern equipment allowed to reconsider completely the tactics of ophthal mosurgeon in treatment of penetrating eye injuries by simultane­ous and complete treatment of the whole complex of the damaged eye tissues by the so-called optico-reconstructive surgery.

By indications the surgeon performs simultaneous suture of the cornea or sclera wound, removal of the foreign body, plastics of the damaged iris, cataract extraction, vitrectomy, implantation of the introocular lens.

If the perforating eye wound is suspected, the entry hole is treat­ed, sclera is revised and if the exit is found it is treated by apply­ing scleral sutures, diathermo- or cryocoagulation of the sclera around the wound to prevent retinal detachment. When there is a foreign body behind the eye, it is removed if possible to prevent the abscess process further on.

The ophthalmosurgeon's treatment management in penetrating wounds complicated by intraocular foreign bodies depends on the localization, character, size of the fragment, its magnetic properties. The magnetic properties of the fragment are determined with the help of special devices — electronic locators. Magnetic foreign bodies must be removed urgently by any magnet but in small magnets from cobalt-samarium alloy it is preferable to perform microsurgery.

There are three ways of removal of foreign bodies from the an­gle of the anterior chamber or the lens. To define the exact localiza­tion of the foreign body in the angle of the anterior chamber (espe­cially amagnetic, e.g. glass) gonioscopy must be performed.

The removal is made by separating conjunctiva from the lymbus and the corneal-scleral incision by layers in the lymbus area with peak formation. If the foreign body is in the posterior chamber the method of approach is the same but iridectomy is performed over the foreign body and the fragment is led out from the posterior cham­ber through eye coloboma by magnet. Sometimes the foreign body in the lens does not disturb its transparency and high visual acuity is preserved. Magnetic fragment must be removed immediately de­spite the risk of lenticular opacity progressing otherwise complete traumatological cataract is inevitable. Small magnetic foreign bod­ies located in the transparent lens must be led out along the wound canal without additional traumas of the anterior lenticular capsule (at early terms — via entrance in the cornea and anterior lenticular capsule). After removal of the fragments the incision in the copsule must be closed by the iris to prevent further lenticular opacity. If the foreign body in the lens is large and there is damage of the an­terior capsule which is accompanied by swelling of the lenticular mass, the foreign body is removed together with extraction of the traumatic cataract.

Most of the foreign bodies are removed from the eye in a dias-cleral way. Foreign bodies located at the wall (close to the eye mem­branes) within 16-18 mm of the lymbus plane are removed episcle­ral^ according to their localization. Additional methods are used to localize foreign body exactly during the operation: ultrasonic diag­nosis, diaphanoscopy with fibrous optics, scleral magnetic test.

In fixed magnetic foreign bodies, at first the course of fibrinolysine treatment as parabulbar injections in combination with magnetic trac­tion resulting in fibrin lysis, separation of foreign body from the mem­branes, its transfer to anterior section of the vitreous are carried out. It is removed from there diasclerally across flat part of the ciliary body. To prevent retinal detachment after transvitreal removal of the foreign body prophylactic retinal photocoagulation is indicated.

Removal of the amagnetic foreign bodies from the eye is much more difficult. To fulfil the procedure we use special dressing for­ceps with zummer signalization (which is switched on approach­ing or contacting the metallic foreign body), endoscopes and vit-reoscopes with fibrous optics. Foreign bodies are removed under the control of stereoroentgenoscopy.

Date: 2015-02-03; view: 1461