Trauma to the eyeball

Closed eye trauma is often defined as blunt trauma. The corneoscleral membranes of the eyeball remain intact, but intraocular damage may occur.

An open injury to the eyeball implies the presence of a penetrating wound to the cornea or sclera.

Contusion of the eyeball is a closed injury resulting from blunt trauma. The injury may be localized at the site of application of the injuring object or at a distant segment.

A ruptured eyeball is a penetrating wound caused by blunt trauma. The eyeball is torn at its weakest point, which may not be at the site of impact.

Eyeball injury - a wound caused by a sharp object at the site of impact.

A superficial wound of the eyeball is a non-penetrating wound caused by a sharp object.

Penetrating injury of the eyeball is a single wound, usually caused by a sharp object, without an exit wound. Such a wound may be accompanied by the presence of a foreign body.

Perforation (through wound) consists of two full-thickness wounds, one of which is the entrance, the other is the exit. Usually caused by a wounding object with a high impact velocity.

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Blunt trauma to the eyeball

The most common causes of blunt trauma are tennis balls, rubber bands from luggage carts, and champagne corks. The most severe blunt trauma is considered to be anteroposterior compression and simultaneous expansion in the equatorial direction, caused by a short-term but significant increase in intraocular pressure. Although such an impact is primarily mitigated by the iridocrystalline diaphragm and the vitreous body, damage can occur at a distant site, such as the posterior pole. The degree of intraocular damage depends on the severity of the injury and, for unknown reasons, is largely concentrated in both the anterior and posterior sections. In addition to existing intraocular damage, blunt trauma is dangerous due to remote complications, so dynamic observation is essential.

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Injuries to the eyeball in the anterior segment

1. Corneal erosion is a fluorescein stained disruption of the epithelial layer. If it is located in the projection of the pupil, vision may be significantly reduced. This rather painful condition is usually treated with cycloplegia for comfort and the administration of an antibacterial ointment. Although patching was the standard treatment in the past, it is now clear that the cornea heals more quickly and painlessly without patching.
2. Corneal edema may develop secondary to local or diffuse dysfunction of the corneal endothelium. It is usually associated with folds of Descemet's membrane and stromal thickening, which resolve spontaneously.
3. Hyphema (hemorrhage into the anterior chamber) is a common complication. The source of the hemorrhage is the vessels of the iris or ciliary body. Red blood cells settle downward, forming a fluid level, the size of which should be measured and recorded. Usually, traumatic hyphema is harmless and short-lived, but requires daily observation until it resolves spontaneously. The immediate risk is secondary hemorrhage, usually more severe than the primary hyphema, which may occur at any time during the week after the initial injury (usually within the first 24 hours). The main goals of treatment are to prevent secondary hemorrhage, control the increase in intraocular pressure, and avoid complications. Oral tranexanoic acid 25 mg/kg 3 times daily and antibiotics are given. There are different opinions, but mydriasis with atropine is essential to prevent further hemorrhage. Hospitalization is desirable for several days to control intraocular pressure, with an increase in which treatment is prescribed to help prevent secondary corneal imbibition with blood. In traumatic uveitis, steroids and mydriatics are prescribed.
4. The iris may have structural and/or functional abnormalities.
   • Pupil. Severe contusion is often accompanied by a transient myod caused by pigment deposition on the anterior capsule of the lens (Vossius ring), which corresponds to the size of the narrow pupil. Damage to the iris sphincter leads to traumatic mydriasis, which is permanent: the pupil reacts sluggishly or does not react to light, accommodation is reduced or absent;
   • iridodialysis - separation of the iris from the ciliary body at the root. In this case, the pupil is usually D-shaped, and dialysis appears as a dark biconvex area near the limbus. Iridodialysis may be asymptomatic if the defect is covered by the upper eyelid; if it is located in the lumen of the eye slit, accompanied by monocular diplopia and a blinding light effect, surgical restoration of the defect is sometimes required. Traumatic aniridia (360 iridodialysis) is extremely rare;
   • The ciliary body may respond to severe blunt trauma by temporarily stopping aqueous secretion (ciliary shock), leading to hypotension. Tears extending to the middle of the ciliary body (angle recession) are associated with a risk of secondary glaucoma.
5. Crystalline lens
   • Cataract is a common consequence of blunt trauma. The proposed mechanism includes both traumatic damage to the lens fibers themselves and rupture of the lens capsule with fluid penetration inside, hydration of the lens fibers and, as a result, its opacity. Opacity under the anterior lens capsule in the form of a ring can be located in the projection of the Vossius ring. Often, opacity develops under the posterior capsule in the cortical layers along the posterior sutures ("extrusion" cataract), which can subsequently disappear, remain stable or progress with age. Surgical treatment is necessary for severe opacity;
   • Subluxation of the lens may result from rupture of the supporting ligamentous apparatus. A subluxated lens is usually displaced in the direction of the intact zonule of Zinn; if the lens is displaced posteriorly, the anterior chamber deepens at the site of the rupture of the zonule of Zinn. The edge of the subluxated lens may be visible during mydriasis, and the iris trembles with eye movement (iridodenesis). Subluxation causes partial aphakia in the projection of the pupil, which may lead to monocular diplopia; in addition, lenticular astigmatism may appear due to the displacement of the lens;
   • Dislocation with a 360 rupture of the subciliary zonule is rare, and the lens may be displaced into the vitreous body or into the anterior chamber.
6. A rupture of the globe results from severe blunt trauma. The rupture is usually localized in the anterior segment, in the projection of the Schlemm's canal, with prolapse of intraocular structures, such as the lens, iris, ciliary body, and vitreous body. Sometimes the rupture occurs in the posterior segment (occult) with minor visible damage to the anterior compartment. Clinically, a occult rupture should be suspected in the presence of asymmetry in the depth of the anterior chamber and a decrease in intraocular pressure in the injured eye. The principles of suturing scleral ruptures are described below.

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Damage to the posterior part of the eyeball

1. Posterior vitreous detachment may be associated with vitreous hemorrhage. Pigment cells in the form of "tobacco dust" may be located in the anterior vitreous.
2. Retinal concussion involves shaking of the sensory part of the retina, which leads to its cloud-like swelling in the form of a grayish area. Concussion usually causes changes in the temporal quadrants of the fundus, sometimes in the macula, then they talk about the "cherry pit" symptom. The prognosis for mild cases is good, with spontaneous resolution without complications within 6 weeks. Severe damage to the macula may be combined with retinal hemorrhage. Remote post-traumatic changes: progressive pigment dystrophy and the formation of a macular hole.
3. A choroidal rupture involves the choroid itself, Bruch's membrane, and pigment epithelium. The rupture may be direct or indirect. Direct ruptures are located in the anterior region on the affected side and are parallel to the serrated line, while indirect ruptures are located opposite the affected site. A fresh rupture may be partially masked by subretinal hemorrhage, which may break through the inner membrane with subsequent hemorrhage under the hypoploid membrane or into the vitreous body. After a certain time, after the blood has resolved, a white vertical strip of exposed sclera appears in the shape of a crescent, often involving the macula or exposing the optic disc. If the macula is damaged, the prognosis for vision is poor. A rare late complication is secondary neovascularization of the choroid, which may lead to hemorrhage, scarring, and deterioration of vision.
4. Retinal tears that can cause retinal detachment are divided into 3 main types:
   • a retinal detachment caused by traction of the inelastic vitreous body along its base. A possible detachment of the vitreous base causes the "basket handle" sign, which includes part of the ciliary epithelium, the "serrated" line, and the adjacent retina, under which the adjacent vitreous body is wedged. A traumatic rupture may occur in any sector, but is more common in the superonasal, possibly because the impact of the traumatic factor most often occurs in the lower temporal direction. Although ruptures occur during trauma, retinal detachment usually develops after several months. The process is slow with an intact vitreous body;
   • equatorial rupture is less common and is caused by direct trauma to the retina at the site of injury to the sclera. Sometimes such ruptures can involve more than one segment (giant ruptures);
   • A macular hole can occur both during an injury and in the late period as a result of a retinal concussion.
5. Optic nerve
   • Optic neuropathy is a rare but serious complication that causes significant vision loss, caused by contusion injuries to the head, especially the forehead. It is believed that such an impact transmits a shock wave to the optic canal, damaging it. As a rule, at the beginning the optic disc and the fundus are generally intact. Only objective studies show emerging changes in the disc. Neither steroid treatment nor surgical decompression of the optic canal prevent the development of optic atrophy within 3-4 weeks;
   • Optic nerve avulsion is a rare complication and usually occurs when a wounding object becomes lodged between the globe and the orbital wall, displacing the eye. The determining mechanism is a sudden, critical rotation or forward displacement of the globe. The rupture may be isolated or associated with other ocular or orbital injuries. Ophthalmoscopy shows a depression where the optic nerve head has been torn from its insertion. No treatment is indicated: the visual prognosis depends on whether the rupture is partial or complete.

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Non-accidental injuries to the eyeball

In children under 2 years of age, non-accidental injuries should be considered as a case of physical abuse of the child (rocked baby syndrome). This syndrome can be suspected in the presence of characteristic ophthalmological symptoms and the absence of an alternative explanation. The diagnosis should be discussed with a pediatrician (hospitals specializing in children should have a group to study cases of abuse of children). The injuries may be caused by severe motion sickness, but a thorough examination may also reveal signs of traumatic effects. Brain damage is considered to be the result of hypoxia and ischemia due to apnea more often than from compression or impact.

1. They often manifest as irritability, drowsiness and vomiting, which is initially misdiagnosed as gastroenteritis or another infection, so the presence of damage is not recorded.
2. Systemic disorders: subdural hematoma and head injuries ranging from skull fractures to soft tissue contusions. Many of the surviving patients have neurological pathology.
3. Eye disorders are numerous and variable.

Retinal hemorrhage (unilateral or bilateral) is the most common sign. The hemorrhage usually involves different layers of the retina and is most obvious at the posterior pole, although it often extends to the periphery.

• Periocular ecchymoses and subconjunctival hemorrhage.
• Low visual function and afferent pupillary defects.
• Vision loss occurs in approximately 20% of victims, usually as a result of brain damage.

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Penetrating trauma of the eyeball

Penetrating injuries are three times more common in men than in women, and occur at a young age. The most common causes are assault, domestic accidents, and sports injuries. The severity of the injury is determined by the size of the wounding object, its speed during impact, and the material of the object. Sharp objects, such as knives, cause well-adapted wounds to the eyeball. However, the severity of the injury caused by a foreign body is determined by its kinetic energy. For example, a large air rifle BB gun pellet, although moving relatively slowly, has high kinetic energy and can thus cause significant intraocular damage. In contrast, a fast-moving shrapnel fragment has low mass and will therefore cause a well-adapted rupture with less intraocular damage than an air pistol pellet.

It is extremely important to consider the factor of infection in penetrating wounds. Endophthalmitis or panophthalmitis are often more serious than the initial wound and can even lead to loss of the eye.

Traction retinal detachment

Tractional retinal detachment may be secondary to vitreous prolapse into the wound and hemophthalmos, which stimulates fibroblastic proliferation in the direction of the trapped vitreous. Subsequent contraction of such membranes leads to tension and twisting of the peripheral retina at the site of vitreous fixation and ultimately to tractional retinal detachment.

Tactics

The initial assessment should be performed in the following order:

• Determining the nature and extent of any life-threatening problems.
• History of injury, including circumstances, timing, and injury object.
• Complete examination of both eyes and orbits.

Special studies

• Plain radiographs are indicated when a foreign body is suspected;
• CT is preferred over plain radiography for the diagnosis and localization of intraocular foreign bodies. This study is also valuable in determining the integrity of intracranial, facial, and intraocular structures;
• Ultrasound can help in the diagnosis of intraocular foreign bodies, ruptured eyeballs, and suprachoroidal hemorrhages.

MRI is contraindicated in the presence of metallic intraocular foreign bodies and retinal detachment. It also helps in planning surgical treatment, such as the placement of infusion ports during vitrectomy or the need for drainage of suprachorionic hemorrhage;

• Electrophysiological studies are necessary to assess the integrity of the retina, especially if some time has passed since the injury and there is a suspicion of the presence of an intraocular foreign body.

Principles of Primary Processing

The method of primary treatment depends on the severity of the wound and associated complications, such as iris impingement, anterior chamber emptying, and damage to intraocular structures.

1. Small corneal wounds with preserved anterior chamber do not require suturing because they often heal spontaneously or when covered with a soft contact lens.
2. Moderately sized corneal wounds usually require suturing, especially if the anterior chamber is shallow or moderately deep. If the tear extends to the limbus, it is important to expose the adjacent sclera and continue scleral closure. A shallow anterior chamber may spontaneously heal when the cornea is sutured. If it does not, the chamber should be repaired with balanced salt solution. After surgery, a contact lens may be used as a bandage for a few days to ensure that a deep anterior chamber is maintained.
3. Corneal wounds with iris prolapse. Treatment depends on the extent and degree of infringement.
   • A small portion of the iris, pinched for a short time, is returned to its place and the pupil is constricted by introducing acetylcholine into the chamber.
   • Large incarcerations of the prolapsed portion of the iris should be excised, especially if the incarceration has been going on for several days or the iris appears non-viable, as there is a risk of developing endophthalmitis.
4. Corneal wounds with lens damage are treated by suturing the wound and removing the lens using phacoemulsification or a vitreotome. The latter method is preferable if there is damage to the vitreous body. Primary implantation of an intraocular lens contributes to better functional results and a low percentage of subsequent complications.
5. Anterior scleral wounds limited to the rectus muscle insertions (i.e. anterior to the Tillaux spiral and also the serrated line) have a better prognosis than posterior wounds. Anterior scleral wounds may be associated with serious complications such as iridocyliary prolapse and vitreous entrapment. If not properly treated, entrapment may result in subsequent vitreoretinal traction and retinal detachment. Each intervention should be accompanied by repositioning of the prolapsed viable uveal tissue, resection of the prolapsed vitreous, and wound closure.

Cellulose swabs should not be used to remove the vitreous due to the risk of causing vitreous traction.

6. Posterior scleral wounds are often combined with retinal tears, with the exception of superficial wounds. The scleral wound is identified and sutured, moving from front to back. Sometimes it is necessary to act on the retinal tear for prophylactic purposes.

During treatment, it is very important not to apply excessive pressure to the eye and eliminate traction to prevent or minimize loss of intraocular contents.

Purpose of secondary processing

If necessary, secondary debridement for posterior segment trauma is usually performed 10 to 14 days after the primary debridement. This allows time not only for wound healing but also for the posterior vitreous detachment to develop, making vitrectomy easier. The main goals of secondary debridement are:

• Remove opacities of the media such as cataracts and hemophthalmos to improve vision.
• To stabilize disturbed intraretinal relationships to prevent long-term complications such as tractional retinal detachment.