A scleral laceration is a severe injury to the eye, representing a full-thickness breach of the outer protective layer known as the sclera. This injury is classified as an open globe injury, meaning the structural integrity of the eyeball is compromised. Due to the high risk of infection, permanent vision loss, and damage to internal ocular contents, a scleral laceration constitutes an immediate medical emergency. Prompt recognition and transport to a specialized facility are paramount for the best possible outcome.
Understanding the Sclera and Laceration Definition
The sclera is the dense, opaque layer commonly referred to as the white of the eye, forming the posterior five-sixths of the eyeball’s outer coat. This robust, fibrous tissue is primarily composed of tough collagen and elastic fibers, giving the eye its rigidity and shape. It extends from the transparent cornea at the front to the sheath around the optic nerve at the back.
The primary function of the sclera is to provide a protective shell for delicate internal structures, such as the retina and lens, shielding them from external trauma and maintaining stable internal pressure. It also serves as the attachment point for the six extraocular muscles that control eye movement.
Lacerations often result from high-velocity impact or sharp, penetrating trauma, such as accidents involving metal fragments, glass, or tools. Blunt trauma, like a forceful blow from a fist or ball, can also cause a scleral rupture, typically occurring at the weakest points near the eye muscles. The mechanism of injury determines the wound’s characteristics.
Identifying Symptoms and Diagnosis Methods
The presence of a scleral laceration is signaled by severe, sudden eye pain and a dramatic decrease in visual acuity immediately following trauma. A visible sign is often a significant subconjunctival hemorrhage, which is extensive bleeding beneath the conjunctiva that obscures the normal white color of the eye. This hemorrhage may mask the underlying wound, making the true extent of the injury difficult to determine without specialized examination.
Other physical signs may include a distorted or peaked pupil, where the iris tissue is pulled toward the wound site, or the visible extrusion of dark, internal ocular contents like the uvea or vitreous gel. Diagnosis begins with documenting the patient’s visual acuity, which serves as a baseline and a strong predictor of the final outcome.
A gentle, non-pressurized examination is then conducted by an eye care professional using a slit lamp microscope. During this examination, the Seidel test may be performed, which uses a fluorescein dye to identify aqueous humor leaking from the wound, appearing as a dark stream against the illuminated dye.
A computed tomography (CT) scan of the orbit is the preferred method to rule out the presence of an intraocular foreign body (IOFB) or associated orbital fractures. Ultrasound is avoided if a laceration is suspected, as the pressure from the probe can cause further prolapse of internal contents.
Emergency Protocol and Stabilization Before Surgery
Immediate action focuses on protecting the eye from further damage and preparing the patient for surgery. The injured person must avoid rubbing or applying any pressure to the affected eye. They should immediately shield the eye with a rigid eye shield, such as a Fox shield or the bottom of a paper cup, and seek emergency medical care.
Upon arrival, the patient is stabilized. Given the open nature of the wound, broad-spectrum intravenous (IV) antibiotics are administered promptly to provide prophylactic coverage against potential infection, known as endophthalmitis. Tetanus prophylaxis is also provided, depending on the patient’s vaccination history and the nature of the injury.
Pain and nausea are managed with appropriate analgesics and anti-emetics, as straining or vomiting can significantly increase intraocular pressure and cause further loss of internal eye structures. The patient is kept on nil per os (NPO) status in preparation for general anesthesia. General anesthesia is chosen over local anesthesia because the injection of local anesthetic can inadvertently raise pressure inside the eye, risking additional extrusion of contents.
Surgical Treatment and Expected Visual Outcome
The definitive management for a scleral laceration is primary surgical repair, performed as soon as the patient is medically stable. The main goal is to achieve a watertight closure of the scleral wound to restore the globe’s anatomical integrity and prevent the entry of microorganisms. The surgeon carefully cleans the wound edges and uses fine, non-absorbable sutures, such as 8-0 or 9-0 nylon, placed perpendicular to the wound to close the defect.
Any prolapsed internal tissue, such as the iris or ciliary body, is carefully inspected. If the tissue appears healthy, it is gently repositioned back inside the eye. Necrotic or severely contaminated tissue must be meticulously removed to reduce the risk of future inflammation or infection. The laceration is closed sequentially, often starting anteriorly and moving toward the posterior extent, ensuring the correct alignment of the scleral edges.
Prognosis is generally better if the patient had good visual acuity at presentation and if the laceration is small and located anteriorly. Factors associated with a poorer visual outcome include a large wound length, significant involvement of the retina or optic nerve, or a delay in surgical repair beyond 24 hours. Post-operatively, patients are monitored for potential long-term complications, including secondary retinal detachment, chronic inflammation, or infectious endophthalmitis.