Optometry’s Role in Open Globe Management
Handling patient cases promptly can help avoid vision loss.
Alberta Pengo, OD, and Natalie Townsend, OD, FAAO
Modern Optometry
Ocular trauma is a leading cause of preventable blindness in developed countries. After sustaining an eye injury, patients often present to their optometrist for guidance. It is important, then, for optometrists to be able to identify, or know when to suspect, an open globe injury, as these injuries carry the poorest prognoses, especially if not identified quickly. First things first, we need to know what we’re dealing with and how to classify our findings. CLASSIFICATION The ability to evaluate patients with ocular trauma and describe the injury to a referring physician reduces ambiguity about the status of the eye. Open globe injuries, as defined by the Birmingham Eye Trauma Terminology system, are full-thickness defects of the eye wall, cornea, and/or sclera.1 Open globe injuries are subdivided by their mechanism of action. Blunt trauma to the eye wall, an inside-out mechanism, can cause a rupture due to an increase in IOP.1,2 Lacerations, an outside-in mechanism, are full-thickness defects created by a sharp or high-velocity object.2,3 Penetrating injuries have the same entry and exit wound. Perforating injuries have a different entrance and exit wound. Intraocular foreign bodies have an entrance wound and a retained foreign body. EPIDEMIOLOGY The main risk factors for ocular injury are young age, male gender, and failure to wear eye protection during high-risk activities.4,5 Fifty-eight percent of patients who sustain ocular injuries are under 30 years of age.5 In the United States, males are five-times more prone to ocular injuries than their female counterparts.4 Most injuries take place at home or in the workplace.4 Blunt and sharp objects, such as rocks, fists, scissors, and knives, are the most common culprits.4 Injuries among teenagers are most commonly secondary to BB guns or baseballs.4 Falls are the main cause of ocular injuries in older patient populations.6 VISUAL POTENTIAL Ocular penetrating and perforating injuries often result in vision loss, defined as BCVA of 20/40 or worse.7 The chance of visual recovery post-injury can be calculated using the Ocular Trauma Score, which considers the material of the object, initial visual acuity, type of injury, presence of a relative afferent pupillary defect, retinal detachment, and/or endophthalmitis.8,9 Ruptured globe injuries with an initial VA of less than 20/200 carry a poorer prognosis.4,10 The Ocular Trauma Score is a helpful clinical tool for educating the patient on their potential visual function and for assisting in the clinical decision-making process.4,5 DETAILED HISTORY Inquire about the mechanism of injury, time of injury, visual acuity before injury, and nature of the incident.2,3 In the setting of an intraocular foreign body, further details should be gathered regarding the physical characteristics of the object, the origin of the foreign body, and its speed, distance, and direction toward the eye.2,3 Note whether prescription glasses, sunglasses, or eye protection was used during the time of the incident.