Eye Trauma, Blunt

Article Author:
Michael Mohseni
Article Editor:
Bradley Bragg
Updated:
10/27/2018 12:31:34 PM
PubMed Link:
Eye Trauma, Blunt

Introduction

Blunt injury to the eye can lead to various intrinsic eye injuries. Globe rupture and retrobulbar hematoma are two emergent entities that the clinician may encounter, and these are the focus of this section. Typical symptoms of globe rupture include eye deformity, eye pain, and vision loss, though depending on the clinical suggestion the deformity may not be readily apparent on the exam. Similarly, a retrobulbar hematoma may present with eye pain and vision loss, but proptosis helps to clinch this diagnosis.  Both are vision threatening diagnoses and require emergency ophthalmologic consultation for definitive measures.

Etiology

Globe rupture occurs when there is a defect in the cornea, sclera, or both structures. Most often, globe rupture occurs after direct penetrating trauma; however, if sufficient blunt force is applied to the eye, the intraocular pressure can increase enough to rupture the sclera.

A retrobulbar hematoma is frequently associated with orbital trauma and associated orbital floor fractures. This trauma may also occur iatrogenically during sinus surgery, ocular surgery, or other eye procedures. In the setting of anticoagulation, this may occur in rare scenarios with increases in Valsalva (e.g., from vomiting, straining, or coughing).

Epidemiology

The incidence of globe injuries is quoted as 3.5 eye injuries per 100,000 persons, with males constituting about 80% of open globe injuries.  Injuries in the pediatric population are more often with sharp objects directly penetrating the globe (e.g., writing utensils, scissors, or knives).  In the adult population, the cause is often blunt trauma (e.g., motor vehicle collisions, altercations, or work-related injuries involving hammering). In the elderly, globe rupture is most often as a result of falling.

The incidence of retrobulbar hematoma is rare; it has been quoted as less than 1%. However, there is a strong association between this diagnosis and subsequent blindness.

Pathophysiology

Globe rupture occurs when there is a defect in the cornea, sclera, or both structures. Most often globe rupture occurs after direct penetrating trauma; however, if sufficient blunt force is applied to the eye, the intraocular pressure can increase enough to rupture the sclera.  The rupture site is most commonly near the globe’s equator posterior to the insertion of the rectus muscles, which is where the sclera is weakest and thinnest.

A retrobulbar hematoma occurs when there is an accumulation of blood in the retrobulbar space. As blood collects behind the eye, there is increased intraocular pressure, which can subsequently cause stretching of the optic nerve. Within a matter of several hours, decreased ocular perfusion can lead to permanent blindness.

History and Physical

A high suspicion for globe injury should be suspected in any patient reporting any direct eye trauma, continuing eye pain, and vision deficit. The mechanism of the injury should be elicited as well as the time it occurred. It is important also to inquire about any anticoagulant use.

In globe rupture, physical examination findings may reveal decreased vision or frank vision loss, the irregular contour of the globe, teardrop pupil, hyphema, or a shallow anterior chamber on the slit-lamp exam. The Seidel sign is positive in globe rupture, indicating the flow of aqueous humor from the injury site in the fluorescein-stained eye. However, if the globe rupture is obvious, testing for the Seidel sign should be avoided.

The clinical presentation of retrobulbar hematoma is classical with proptosis and severe eye pain. As in globe rupture, vision loss may be reported.

There may be associated periorbital swelling, ecchymosis, or subconjunctival hemorrhage in either of these entities depending on the mechanism of the injury.

Evaluation

Visual acuity should be checked in each of the eyes separately, if possible, taking care not to manipulate any possible intrinsic globe injury.  Pupillary defects should also be noted.

A thorough evaluation of any concomitant intracranial and facial bony injury should be pursued.  A high number of globe ruptures and retrobulbar hematomas are associated with fractures, in particular of the orbital floor.  Extra-ocular motility testing may be decreased in the affected eye because of entrapment, intrinsic globe deformity, or retrobulbar hematoma.

Laboratory evaluation should be pursued as the clinical situation dictates in the setting of trauma or anticoagulant use.   Computed tomography (CT) imaging can rule out any additional maxillofacial injuries while confirming the diagnosis.  In addition to globe deformity and retrobulbar hematoma, CT imaging can evaluate for foreign bodies, scleral disruption, and even vitreous hemorrhage.

Treatment / Management

For globe rupture, emergency department treatment includes supportive measures to prevent worsening of the injury or extrusion of intraocular contents. Hence, antiemetics should be provided to prevent Valsalva from vomiting, which could lead to increased intraocular pressures and subsequent loss of aqueous fluid. Analgesia should be provided as needed. A rigid eye shield should be placed, and additional manipulation of the eye should be avoided. The patient should be placed in a semi-recumbent position.

Similarly, in retrobulbar hematoma, analgesia and antiemetic should be provided.  Definitive therapy, however, is immediate decompression with a lateral canthotomy and inferior cantholysis. This can be performed by the emergency medicine provider or the ophthalmologist if there are no delays in the consultant being able to perform this procedure. Vision prognosis is time-sensitive in this setting with poorer outcomes seen in delays of greater than 4 hours from time of symptoms. Prophylactic antibiotics can be used to prevent secondary endophthalmitis.

In the setting of globe injury or retrobulbar hematoma, emergent consultation with Ophthalmology is warranted. Definitive management in these diagnoses is surgical repair by the appropriate ophthalmologic specialist.

Differential Diagnosis

The differential diagnosis of blunt trauma to the eye includes globe rupture, retrobulbar hematoma, traumatic glaucoma, hyphema, orbital blowout fracture with entrapment, foreign body, scleral disruption, and vitreous hemorrhage.

Prognosis

In patients receiving prompt treatment and evaluation, outcomes with retrobulbar hematoma and globe rupture can be satisfactory with preservation of vision. However, the extent of the initial injury and mechanism of injury often predicts whether poor outcomes might be expected.

Pearls and Other Issues

Avoid any unnecessary manipulation of the globe (including tonometry) to prevent any extrusion of intraocular contents. 

Obtain appropriate imaging to rule out concomitant bony injury or intracranial trauma.

Provide analgesia and antiemetics to prevent Valsalva maneuvers that may worsen globe rupture or retrobulbar hematoma.

A protective rigid eye shield should be utilized to prevent any additional injury; eye patches are contraindicated.

Provide prophylactic antibiotics to help prevent endophthalmitis.

Seek emergent Ophthalmology consultation for definitive measures, but do not delay lateral canthotomy for patients with known retrobulbar hematoma.