Ocular trauma or eye injuries are an important cause of visual loss and disability. Here’s what you should know about it
Eye trauma is an important cause of visual loss and disability. Posterior segment trauma (the back two-thirds of the eye) is divided into non-penetrating and penetrating injuries.
A. Non-penetrating injuries that involve the posterior segment are often the result of severe, blunt, concussive blows to the eyeball and result in special types of damage to the eye.
B. Penetrating injuries are divided can be classified into
- Rupture secondary to blunt injury (such as being struck by a rock or associated with a fall),
- Lacerating injuries (involved in, for instance, a knife stab wound or a glass cut)
- Injuries related to intraocular (in the eye) foreign bodies.
Other complications arising from ocular trauma
What to do in case of an injury
1. Eye examination
The initial clinical examination should be as complete as possible, but any further injury to the eyeball should be avoided. In some cases, after penetrating trauma, it may be difficult to assess precisely the patient’s visual acuity; however, assessment of visual acuity is important. The level of vision at presentation is an accurate predictor of the long-term visual prognosis. The pupils should be examined carefully for the presence of an afferent pupillary defect. The presence or absence of an afferent pupillary defect provides important information about the extent of intraocular injury and may provide information as to the visual prognosis of the patient.
If the fundus can be visualized, the presence of retinal detachment, retina tears, choroidal haemorrhage, or intraocular foreign body should be sought. Early in the course following injury it is, at times, possible to obtain a view of the fundus using indirect ophthalmoscopy; this information may prove useful in subsequent treatment decisions.
2. Diagnosis and ancillary testing
Ancillary testing is sometimes used to assist the evaluation of patients who have penetrating injuries. Radiopaque foreign bodies are usually evident on standard, orbital, plain film radiographs. Computed tomography is helpful in the evaluation of both intraocular and periocular structures. Also, computed tomography may help to determine the presence of a metallic intraocular foreign body or to ascertain the presence or degree of periocular damage.
Diagnostic ultrasound can also provide useful information about the status of intraocular structures. Ultrasound can localize intraocular foreign bodies and may provide some advantage over other imaging techniques when the presence or location of a non-metallic intraocular foreign body needs to established.
After the initial primary closure, ultrasound may be used to evaluate the extent of intraocular injury and to plan secondary surgical intervention. Ultrasound accurately detects choroidal haemorrhage, posterior scleral rupture, retinal detachment, and subretinal haemorrhage. On echography, choroidal haemorrhage appears as a dome-shaped elevation with echodense fluid in the suprachoroidal space. Retinal detachment is seen as a highly reflective, mobile membrane that inserts into the optic nerve.
A variety of retinal injuries may occur with blunt injury to the eye ball; these include macular hole, peripheral retinal tear, giant retinal tear, retinal dialysis, and avulsion of the vitreous base. Management of these injuries depends on the nature of the retinal injury and on the presence of retinal detachment and / or vitreous haemorrhage; it may include prophylactic laser photocoagulation or cryopexy, scleral buckling, and pars plana vitrectomy. Haemorrhagic necrosis of the retina (chorioretinitis sclopetaria) is a special circumstance that results from severe contusion injury of the eye ball (e.g., missile injury).
A common finding with blunt injuries, which may lead to acute visual loss, is Berlin’s edema (commotio retinae,this manifests as a widespread or localized whitening of the retina. Recovery of vision is common; however, some patients may sustain some degree of permanent visual loss often accompanied by subretinal pigmentary changes in the macula.
Chorioretinal rupture may occur as a result of the compressive forces generated by a blunt injury. These ruptures tend to occur in a concentric fashion relative to the optic nerve and may result in severe visual loss if the central macula is involved. Delayed visual loss may also occur as a result of the development of choroidal neovascularization. Laser photocoagulation or subretinal surgical extraction of the neovascular membrane may be indicated in some cases. Direct or indirect trauma to the optic nerve or avulsion of the nerve itself may result in profound loss of vision.
Management of penetrating injuries varies widely according to the severity, extent, and location of the injury. Several general principles of management apply to all penetrating ocular injuries; these include the following:
- Primary closure of the penetrating wound
- Removal of any foreign body material
- Prevention of further or secondary injury to the eye (infection)
- Anatomical and visual rehabilitation of the eye
- Protection of the uninjured eye (protective eyewear)
- General rehabilitation of the patient.
Complicated retinal detachment and proliferative vitreoretinopathy
Complicated retinal detachment with proliferative vitreoretinopathy may occur in some eyes after penetrating ocular injury. Proliferative vitreoretinopathy may manifest as severe, widespread membrane contraction with retinal detachment or as localized macular pucker. In the setting of complicated retinal detachment, general principles for the repair of retinal detachment with proliferative vitreoretinopathy should be used; these include the following:
- Release of all traction by meticulous membrane dissection;
- Placement of an encircling scleral buckle to support the vitreous base and peripheral retinal breaks;
- Reapplication of the retina under gas or silicone oil; and
- Production of chorioretinal adhesion with endolaser photocoagulation.
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