Perforating Ocular Injury

Key points of this disease

• A perforating eye injury is an open globe injury with both an entrance wound and an exit wound (double perforation).
• It is more severe than a penetrating eye injury with only an entrance wound, and ocular collapse occurs due to extrusion of intraocular contents from two sites (anterior and posterior).
• Primary repair within 24 hours after injury significantly reduces the risk of endophthalmitis (OR 0.39, 95% CI 0.19–0.79) ¹⁾.
• Exit wounds often occur in the posterior segment (Zone III), with a high frequency of posterior segment injury and vitrectomy.
• Blast injuries and war wounds involve multiple perforating wounds and can cause damage to multiple eyes.
• There is a high risk of proliferative vitreoretinopathy (PVR), sympathetic ophthalmia, and endophthalmitis, requiring long-term follow-up.

1. What is a perforating eye injury?

A perforating eye injury, based on the Birmingham Eye Trauma Terminology, is defined as a laceration caused by a sharp object with both an entry and an exit wound. It is an open globe injury that penetrates the eye wall from front to back, resulting in both an entry and an exit wound.

It is clearly distinguished from penetrating eye injury (entry wound only) and globe rupture (caused by blunt force). Perforating injury is also called double perforation and is more severe than penetrating injury because it involves two wounds (front and back).

Perforating injury

Definition: Both entry and exit wounds are present.

Also called double perforation, with ocular contents protruding from two sites (front and back). Severity is relatively high.

Penetrating injury

Definition: Only an entry wound is present.

There is no exit wound, and no penetration into the posterior segment. Relatively milder than perforating injury.

Globe rupture

Definition: A condition in which the cornea or sclera is separated due to a sudden increase in intraocular pressure caused by blunt force.

It is caused by blunt trauma rather than a sharp object.

Zone Classification of Injury

The injury site affects prognosis and is classified into the following three zones¹⁾. In perforating injuries, the exit wound often reaches Zone III, posing a high risk of posterior segment damage.

Zone	Extent	Characteristics
I	Cornea to limbus	Limited to anterior segment
II	Up to 5 mm posterior to the limbus	Anterior to the ora serrata
III	More than 5 mm posterior to the limbus	Posterior segment including the retina

Comparison of Perforating vs. Penetrating

Item	Penetrating	Perforating
Number of wounds	Entry wound only	Entry + exit wounds
Severity	Relatively mild	Relatively severe
Ocular content prolapse	Only at entry site	Two sites (anterior and posterior)
Posterior segment injury	Less common	Frequent (Zone III)
Vitrectomy frequency	Low	High

Epidemiology

The incidence of ocular trauma is estimated at approximately 3.5–4.5 per 100,000 people ¹⁾. The majority of patients are male, with a relative risk about 5.5 times higher than females, and the average age at injury is around 30 years.

In children, the incidence of severe ocular trauma is 11.8 per 100,000 per year. Children account for over 35% of severe ocular trauma, and most are under 12 years old. Because of the added risk of amblyopia, prompt management is especially important in children.

Q What is the difference between perforating and penetrating injuries?

A

A perforating ocular injury has both an entry and an exit wound (double perforation), whereas a penetrating injury has only an entry wound without an exit wound. In perforating injuries, ocular contents may prolapse from both anterior and posterior sites, and posterior segment damage (Zone III) is common, making it more severe than penetrating injuries. The frequency of requiring vitrectomy is also higher in perforating injuries.

2. Main Symptoms and Clinical Findings

Zone III injury in perforating ocular trauma: intraoperative findings of entry wound and posterior exit wound

Mayer CS, et al. Open Globe Injuries: Classifications and Prognostic Factors for Functional Outcome. Diagnostics. 2021;11(10):1851. Figure 4. PMCID: PMC8534971. License: CC BY.

Panels A–C show a self-sealing entry wound (black arrow) in the sclera 2 mm posterior to the limbus. Panels D–F show the surgical field during vitrectomy, where a secondary posterior laceration (exit wound, arrow) is exposed after removal of vitreous hemorrhage. This corresponds to the characteristic anterior and posterior wounds of perforating injury discussed in section “2. Main Symptoms and Clinical Findings.”

Subjective Symptoms

• Eye pain: Occurs immediately after injury. Severity varies depending on the size and location of the perforation.
• Vision loss: Caused by corneal damage, hyphema, lens damage, vitreous hemorrhage, etc.
• Diplopia: Occurs when there is associated damage to extraocular muscles or the orbit.
• Foreign body sensation, blurred vision: In minor injuries, the main complaints may be limited to these.

Clinical findings

• Subconjunctival hemorrhage: If extensive, suspect open globe injury.
• Shallow anterior chamber or flat anterior chamber: An important sign suggesting aqueous humor leakage.
• Hyphema (anterior chamber hemorrhage): May be associated with angle recession or cyclodialysis.
• Peaked pupil: Occurs when the iris is incarcerated in the wound.
• Uveal prolapse: Uveal tissue prolapses and becomes incarcerated through an anterior laceration.
• Hypotony: An important sign suggesting perforating ocular injury.
• Traumatic cataract: Accompanied by anterior subcapsular cortical opacity, Vossius ring, lens subluxation or dislocation.
• Vitreous hemorrhage: Indicates extension of injury to the posterior segment.
• Traumatic retinal tear: More common in the superonasal or inferotemporal quadrant. May appear days after injury even if absent initially.

Findings characteristic of perforating injury

The following findings are characteristic of perforating injury:

• Presence of a posterior exit wound: An exit wound in Zone III (≥5 mm posterior to the limbus).
• Ocular contents prolapse from both anterior and posterior wounds: Vitreous and uveal tissue prolapse through both wounds.
• Ocular collapse: In severe cases, the entire eyeball becomes collapsed.
• Deep hemorrhage: Vitreous hemorrhage and choroidal hemorrhage associated with posterior segment injury.

The Seidel test using fluorescein staining is useful for evaluating full-thickness wounds. Under cobalt blue light, the dye is washed away by aqueous humor leakage (Seidel positive), confirming a full-thickness wound.

Precautions during examination when open globe is suspected

Tests that apply pressure to the eyeball are contraindicated. Do not perform forced duction test, gonioscopy, scleral depression, or B-mode ultrasound. If there is obvious globe deformation or extrusion of intraocular contents, also refrain from measuring intraocular pressure. In perforating injuries, there may be an open wound in the posterior segment, so special attention is needed to avoid worsening of intraocular content extrusion due to pressure.

Q Should perforation be suspected even if anterior segment findings are normal?

A

If there is low intraocular pressure, severe subconjunctival hemorrhage, or hyphema, open globe injury should be suspected. Even if anterior segment findings are mild, if there is a history of injury from a high-speed projectile or stab wound, consider the possibility of perforation and perform CT imaging. If there is an entry wound, CT (1 mm slices) is essential to check for an exit wound in the posterior segment.

3. Causes and Risk Factors

Mechanism of Injury

Perforating ocular injuries occur when a sharp object penetrates the eyeball with sufficient force.

• Sharp objects: Knives, scissors, screwdrivers, nails, sticks, etc. In children, pencils and pens are important causes.
• High-speed projectiles: Metal fragments (from grinders, welding debris), fragments from hammer strikes, glass shards, etc.
• Sports-related: Baseball (self-hit balls, bad hops), golf balls, shuttlecocks, BB pellets, etc.
• Blast injuries: Blast waves and scattered metal/glass fragments cause multiple injuries.

Blast injuries can result in multiple perforating wounds. In the Beirut port explosion (2020), 39 patients with 48 eyes were injured, with open globe injuries in 10 eyes (20.8%) ²⁾. Although 54.2% were superficial injuries, 53.8% required surgical intervention. Fragments and flying glass from the explosion were the main causes of injury ²⁾.

Risk Factors

• Male sex: The relative risk of ocular trauma is about 5.5 times higher than in females.
• Non-use of protective equipment: Not wearing eye protection when using power tools or playing sports.
• Drug and alcohol use: Increases the risk of trauma.
• Children’s writing instruments: Pencils and pens are often perceived as harmless but can cause serious eye injuries.

Infection Risk

The incidence of endophthalmitis in open globe injuries is 2–7%. Infections originating from plants or soil lead to blindness at a high rate. Unlike postoperative endophthalmitis after cataract surgery, endophthalmitis caused by virulent bacteria such as Bacillus species is a concern. In orbital foreign bodies, anaerobic infections (e.g., tetanus) should also be considered.

Prevention and Daily Care

• Always wear protective goggles when using power tools or sanders.
• Use appropriate protective equipment such as goggles or face shields during sports.
• Supervise children carefully when they handle sharp stationery items like pencils and pens.
• If you feel something hit your eye, do not rub it; seek immediate ophthalmological care.

Q Why does eye injury occur in blast trauma?

A

In explosions, both the blast wave itself and flying metal or glass fragments damage the eye. In a survey after the Beirut port explosion, 10 out of 48 eyes (20.8%) in 39 patients sustained open globe injuries, mainly caused by flying glass and debris ²⁾. Blast trauma differs from ordinary eye trauma in that it often results in multiple perforations and bilateral eye injuries.

4. Diagnosis and Examination Methods

CT findings of perforating ocular trauma (axial, coronal, sagittal): metallic foreign body in the posterior pole

Mayer CS, et al. Open Globe Injuries: Classifications and Prognostic Factors for Functional Outcome. Diagnostics. 2021;11(10):1851. Figure 5. PMCID: PMC8534971. License: CC BY.

Axial (A), coronal (B), and sagittal (C) images show a high-density metallic foreign body (white arrow) in the posterior pole, confirming the penetrating path through the globe and the posterior location of the foreign body. This corresponds to the detection of intraocular metallic foreign bodies by CT discussed in the section “4. Diagnosis and Examination Methods.”

The diagnosis of open globe injury is made through a combination of detailed history taking, careful examination, and imaging studies.

History Taking

Obtain detailed information on the time, mechanism, and causative object of the injury. Also check for protective eyewear use, tetanus immunization status, and time of last meal (due to possible general anesthesia). In patients with decreased consciousness, it is important to gather information from family members or others involved.

Ophthalmic Examination

• Visual acuity testing: Visual acuity at the initial visit must be measured for prognosis and documentation.
• Pupillary examination: Check for the presence of a relative afferent pupillary defect (RAPD). This is important for detecting traumatic optic neuropathy.
• Slit-lamp examination: Evaluate corneoscleral lacerations, hyphema, and lens damage. Perform a Seidel test with fluorescein staining to check for aqueous humor leakage.
• Fundus examination: Check for traumatic retinal tears, subretinal hemorrhage, and vitreous hemorrhage. If the view is poor, imaging studies are used as an alternative.

Imaging Studies

Imaging modality	Main indications	Notes
Orbital CT	Foreign body detection, globe deformation, location of exit wound	1 mm thin slices recommended; indicated in all cases
B-mode ultrasound	Evaluation of posterior segment when media opacity	Avoid pressure. Use caution if open wound suspected
X-ray	Detection of metallic foreign bodies	Detectable if ≥2mm and thickness ≥0.4mm

CT scan is indicated for all cases of penetrating ocular trauma. It can simultaneously evaluate the location of intraocular foreign bodies, globe deformation, orbital fractures, and intracranial lesions, and can confirm the extension of the exit wound to the posterior segment. Thin-slice (1mm) sections are recommended.

Additional confirmation in penetrating trauma: If the exit wound is in the posterior segment (Zone III), confirm its location on both axial and sagittal CT views. The closer to the posterior pole, the greater the impact on visual function.

MRI is contraindicated if a metallic foreign body is suspected. It can only be used to confirm non-metallic foreign bodies (e.g., wood fragments, deep fluid collections).

5. Standard Treatment

The priority in treating penetrating ocular trauma is wound closure (primary repair) to prevent infection and extrusion of ocular contents.

Emergency Treatment

• If ocular contents are protruding, apply a protective eye shield without applying pressure to the globe.
• If the eyelid wound or conjunctival sac is contaminated, irrigate thoroughly with normal saline.
• Do not remove foreign bodies at the bedside. Apply a rigid eye shield and plan for controlled removal in the operating room.
• Secure peripheral intravenous access and instruct the patient to fast in preparation for general anesthesia.

Primary Repair (Wound Closure)

Primary repair within 24 hours of injury is recommended. A systematic review and meta-analysis (15 studies, 8,497 eyes) showed that repair within 24 hours reduces the risk of endophthalmitis with an odds ratio of 0.39 (95% CI 0.19–0.79)¹⁾. General anesthesia is typically selected.

Corneal Suturing

Use 10-0 nylon. Aim for watertight closure, but avoid overtightening sutures as it can cause corneal astigmatism and irregular astigmatism; take longer bites.

Scleral Suturing

Use 7-0 nylon as the basic suture, selecting 6-0 to 8-0 nylon depending on the wound location. First, secure the four rectus muscles and explore the wound. If the wound is deep and the rectus muscle obstructs, temporarily detach the tendon. For limbal wounds, first suture with 9-0 nylon, then close the corneal wound with 10-0 nylon and the scleral wound with 9-0 nylon using interrupted sutures.

Procedures Specific to Perforating Injuries (Repair of Exit Wounds)

If the exit wound is in the posterior segment (Zone III), detachment and rotation of the extraocular muscle may be necessary. Explore and suture the posterior scleral wound under direct visualization. Wounds near the posterior pole are technically difficult to suture and should be handled by an experienced surgeon.

Prophylactic Antibiotic Administration

Administer systemic broad-spectrum antibiotics covering gram-positive and gram-negative bacteria. Combination therapy with vancomycin and a third-generation cephalosporin (e.g., ceftazidime) is associated with a reduced incidence of endophthalmitis.

If endophthalmitis is suspected, early surgical intervention is recommended. If inflammation is confined to the anterior chamber, perform anterior chamber washout and inject vancomycin 1 mg/0.1 mL and ceftazidime 2.25 mg/0.1 mL into the anterior chamber and vitreous cavity. If vitreous opacification is extensive, perform emergency vitrectomy.

Secondary Surgery (Vitrectomy)

In perforating injuries, posterior segment damage is frequent, so the proportion requiring secondary surgery (vitrectomy) is higher than in penetrating injuries. In the following cases, consider performing vitrectomy immediately after primary repair.

• When lens swelling has already progressed.
• When the wound extends posteriorly beyond the rectus muscle insertion
• When intraocular foreign body remains
• When vitreous hemorrhage is severe and fundus cannot be visualized

Three-port vitrectomy is performed to remove the opaque vitreous and release incarcerated vitreous. Gas tamponade or silicone oil tamponade is used to achieve retinal reattachment and ensure visibility.

Precautions in treatment

• It is very difficult to heal perforating trauma with a single surgery, and multiple surgeries are often required.
• Secondary complications such as proliferative vitreoretinopathy (PVR), bullous keratopathy, and secondary glaucoma may occur postoperatively.
• Suturing of posterior exit wounds is technically challenging, and if retinal or choroidal damage is involved, visual prognosis may be poor.
• Due to the risk of sympathetic ophthalmia, follow-up of not only the injured eye but also the fellow eye is necessary.

Q How many hours from injury to surgery are acceptable?

A

Primary repair within 24 hours of injury is strongly recommended. Systematic reviews and meta-analyses have shown that repair within 24 hours reduces the risk of endophthalmitis with an OR of 0.39 (95% CI 0.19–0.79) ¹⁾. However, within 24 hours, no significant difference in final visual acuity was found between earlier and later repair timing (OR 0.89, 95% CI 0.61–1.29) ¹⁾. Comparison of even earlier time windows within 24 hours remains a topic for future research.

6. Pathophysiology and detailed pathogenesis

Mechanism of perforating injury

A sharp object penetrates the anterior surface of the eyeball (cornea or anterior sclera) and exits through the posterior surface (posterior sclera). During this process, intraocular contents (vitreous, uvea) prolapse through both the entry and exit wounds, leading to ocular collapse. Unlike penetrating trauma, perforating injury is characterized by prolapse and damage of intraocular contents at the exit wound as well.

Specificity of posterior segment injury

When the exit wound reaches Zone III (5 mm or more posterior to the limbus), direct damage to the retina, choroid, and optic nerve occurs. Vitreous gel may become incarcerated in the wound, and contraction can cause traction that tears the opposite retina.

Mechanisms of retinal detachment associated with open-globe injury

• Direct hole formation: The external force directly creates a retinal break, and retinal detachment progresses from that site.
• Secondary traction: Vitreous gel incarcerated in the entry or exit wound contracts, pulling on the opposite retina and causing retinal tears and detachment.

In perforating injuries, there are two sites of vitreous incarceration (entry and exit), so traction occurs from multiple directions, often leading to complex retinal detachment.

Secondary complications

The following secondary changes may occur after initial treatment of the injury:

• Proliferative vitreoretinopathy (PVR): A major cause of poor functional and anatomical outcomes after trauma. Risk is particularly high in perforating injuries.
• Traumatic cataract: Caused by penetrating lens injury or blunt impact.
• Secondary glaucoma: Resulting from hyphema, angle recession, or anterior synechiae.
• Endophthalmitis: Occurs in 2–7% of open-globe injuries. Severe cases may be caused by virulent organisms such as Bacillus species.
• Sympathetic ophthalmia: An autoimmune reaction to uveal antigens from the injured eye causes inflammation in the fellow eye. The latent period ranges from weeks to years.
• Amblyopia in children: In pediatric cases, visual deprivation, anisometropia, or strabismus after injury can lead to amblyopia.

7. Latest research and future perspectives (research-stage reports)

For patients: Please be sure to read

The following content is currently at the research stage or in clinical trials, and is not standard treatment available at general hospitals. It is reference information for professionals regarding future medical developments.

Systematic Review and Meta-Analysis on Timing of Primary Repair

McMaster et al. (2025) conducted a systematic review and meta-analysis on the timing of primary repair after open globe injury and its association with visual outcomes and endophthalmitis rates ¹⁾. Analyzing 15 studies involving 8,497 eyes, they reported the following results.

• Endophthalmitis risk: Repair within 24 hours reduced the odds ratio to 0.39 (95% CI 0.19–0.79).
• Final visual acuity: No significant difference based on repair timing (OR 0.89, 95% CI 0.61–1.29).
• Certainty of evidence: All studies were retrospective and non-randomized, so the certainty was assessed as low.

The authors strongly recommend repair within 24 hours, but more detailed timing comparisons, such as emergency nighttime surgery versus next-morning surgery, await future prospective studies ¹⁾.

Findings on Blast Injuries

Kheir et al. (2021) reported a case series of 39 patients (48 eyes) who sustained ocular trauma after the Beirut port explosion in August 2020 ²⁾. Key findings are as follows.

• Injury patterns: 54.2% were surface injuries (conjunctival lacerations, corneal foreign bodies, etc.), and 20.8% were open globe injuries.
• Surgical intervention rate: 53.8% required surgery.
• Severe cases: 4 eyes (8.3%) with no light perception underwent enucleation or evisceration.
• Clinical challenges: The shutdown of electronic medical records forced a return to basic approaches ²⁾.

For blast injuries, it is important to prepare systems for multiple wounds and injuries to multiple eyes.

Ocular Trauma Score (OTS)

The Ocular Trauma Score (OTS) is a prognostic tool that estimates the probability of visual outcomes based on initial visual acuity, presence of globe rupture, endophthalmitis, penetrating injury, retinal detachment, and relative afferent pupillary defect (RAPD). In a study of 93 combat-related ocular trauma cases, the sensitivity for predicting visual survival (light perception or better) was 94.8%, and the specificity for predicting no light perception was 100%. The OTS is useful for determining treatment strategies and counseling patients with penetrating injuries.

8. References

1. McMaster D, et al. Early versus Delayed Timing of Primary Repair after Open-Globe Injury: A Systematic Review and Meta-Analysis. Ophthalmology. 2025;132:431-441.
2. Kheir WJ, et al. Ophthalmic Injuries After the Port of Beirut Blast. JAMA Ophthalmol. 2021.
3. Luff AJ, Hodgkins PR, Baxter RJ, Morrell AJ, Calder I. Aetiology of perforating eye injury. Arch Dis Child. 1993;68(5):682-3. PMID: 8323341.