Ocular penetrating and perforating injuries
Ocular penetrating and perforating injuries can result in severe vision loss or loss of the eye. Penetrating injuries by definition penetrate into the eye but not through and through--there is no exit wound. Perforating injuries have both entrance and exit wounds. Most individuals sustaining eye injuries are male with an estimated relative risk of 5.5 times greater than women. 
Penetrating or perforating ocular injuries can be due to injury from any sharp or high velocity object. The home is the most frequent location for injuries. The most common blunt objects reported by May et al from the United States Eye injury Registry were rocks, fists, baseballs, lumber and fishing weights. The most common sharp objects were sticks, knives, scissors, screwdrivers and nails.
As noted from the epidemiological studies above, male gender is a large risk factor for ocular trauma. Failure to wear adequate eye protection while performing high risk activities such as baseball, basketball and use of power tools in the home environment have also been noted to be risk factors for eye injuries. Substance abuse including alcohol and marijuana is also known to increase the risk of eye trauma.
Appropriate and adequate eye protection when performing visually threatening activities is the most effective method to prevent ocular trauma. The American Academy of Ophthalmology Eye injury Snapshot is a yearly survey designed to collect data and educate the public about the causes and prevention of eye injuries. Through educational programs such as this, potential eye injuries may be prevented.
It is important to obtain a thorough history from the patient to help identify the timing of the injury and mechanism. Any injuries other than the eye should be ascertained. Questions such as what was the patient doing during the injury and what potential objects could have caused the injury are important prior to physical evaluation. It is important to note whether safety glasses or prescription eyeglasses were being worn at the time of the injury. Also, make sure to ask the patient if he/ she has a history of limited vision in either eye (amblyopia or other prior cause of visual loss).
A pertinent medical history including current medications, allergies, tetanus status, timing of last meal and any ocular history can help with diagnosis and management.
Ophthalmic examination after severe trauma can be difficult. Obtaining a visual acuity and pupillary examination may be the most important elements to ascertain. Obvious trauma requires careful handling of the eye with care taken to prevent any pressure on the globe if an open globe is suspected. A dilated exam should be done to look for intraocular damage as long as there is a view through the pupil. Ultrasonography, if possible without causing further damage to the eye, is helpful when the media preclude a posterior exam. MRI (non-metalic injury) or CT ( if you suspect metallic intraocular foreign body) are indicated if there is a possibility for intraocular foreign body.
Once an extraocular muscles and external examination is complete, a thorough conjunctival and anterior segment examination must be completed if penetrating or perforating injury is suspected.
Subconjunctival hemorrhage, shallow or flat anterior chamber, hyphema, iris deformities, lens disruption, or posterior segment findings such as vitreous hemorrhage, retinal tears, retinal hemorrhage are concerning when seen in a patient with suspected trauma.
Patients with penetrating or perforating injuries usually complain of pain or double vision. In more subtle injuries, there may be minor symptoms such as foreign body sensation or blurred vision.
When direct visualization is not possible, gentle ultrasound and computed tomography should be used to evaluate the globe. Magnetic resonance imaging is contraindicated in any case where a metal object is thought to be involved.
Penetrating or perforating injuries should be evaluated and treated immediately. Depending on the material causing the injury and location of entry, severe vision loss can occur. Risk of endophthalmitis should be assessed and prophylaxis given as indicated.
If surgical exploration is planned, a fox shield, antiemetics, intravenous antibiotics, and update of tetanus status should be completed.
Globe exploration should be performed in suspected penetrating trauma with possible vitrectomy if vitreous hemorrhage with an intraocular foreign body or retinal detachment is present. Otherwise, closure of the open globe is done primarily and then the eye followed carefully with exams and ultrasound until the vitreous hemorrhage resolves or indications for pars plana vitrectomy occur (traction, retinal detachment). For eyes in which the vitreous cavity has been violated, pars plana vitrectomy is frequently performed to avoid tractional retinal detachment when vitreous organization is seen.
- American Academy of Ophthalmology. Retina/Vitreous: Ocular penetrating and perforating injury Practicing Ophthalmologists Learning System, 2017 - 2019 San Francisco: American Academy of Ophthalmology, 2017.
- May DR, Kuhn FP et al. The epidemiology of serious eye injuries from the United States Eye Injury Registry. Graefes Arch Clin Exp Ophthalmol. 2000; 238: 153-7.
- American Academy of Ophthalmology, The 6th Annual Eye Injury Snapshot Project.
- Wong T, Klein B, Klein R. The Prevalence and 5-year incidence of Ocular Trauma-The Beaver Dam Eye Study. Ophthalmology. 2000; 107: 2196-2202.
- Mittra RA, Mieler WF. Controversies in the Management of Open-Globe Injuries Involving the Posterior Segment. Survey of Ophthalmology. 1999; 44: 215-225.