Tool May Help Non-Ophthalmologists Triage Patients With Serious Ocular Injuries

By analyzing retrospective consecutive case series, researchers identified 5 clinical and radiographic variables associated with increased risk of serious ocular injury in patients with orbital fracture to aid non-ophthalmologists in triaging these patients for urgent ophthalmologic evaluation. Analysis findings were published in JAMA Ophthalmology.

Approximately 10% to 25% of facial trauma that presents to the emergency department (ED) involves an orbital fracture, while the overall rate of ocular injury in the setting of ocular fractures is low. Although a large proportion of ocular injuries do not lead to any ophthalmic intervention or long-term ocular sequelae, non-ophthalmologists do not “typically have the materials and experience to do a dilated eye examination to determine whether there is a substantial ocular injury,” researchers wrote.

To devise an algorithm to identify risk factors associated with serious ocular injury, investigators performed a retrospective case series of all consults requested at the Massachusetts Eye and Ear (MEE) Department of Ophthalmology from affiliated hospitals due to orbital fracture between 2013 and 2018.

Case collection was divided into 2 stages for model generation and for validation, while patients who presented directly to MEE via the ophthalmic ED were excluded. All patients were aged 16 or older and a total of 430 patients (500 eyes) were included in the first stage (training) and 88 patients (97 eyes) in the second stage (validation). Researchers collected demographic, symptomatologic, clinical, and radiographic data on each patient in the training stage.

Mean age of the patient population was 53.5 years. “The most common type of fracture was an internal fracture (orbital floor and/or medial wall, collectively 45.8% or 229 eyes) and the most common examination findings were eyelid ecchymoses (65.4%; 327 eyes) and subconjunctival hemorrhage (61%; 304 eyes),” authors wrote.

Of the injuries reported, the rate of substantial ocular injury (defined as requiring urgent ophthalmic attention or being suitable for outpatient follow-up) was 20.4% while rate of injury requiring immediate ophthalmic attention was 14.4%.

A total of 5 variables were associated with increased risk of substantial ocular injury:

• blunt trauma with a foreign object (odds ratio [OR], 19.4; 95% CI, 6.3-64.1; P < .001)
• inability to count fingers (OR, 10.1; 95% CI, 2.8-41.1; P = .002)
• roof fracture (OR, 9.1; 95% CI, 2.8-30.0; P = .002)
• diplopia on primary gaze (OR, 6.7; 95% CI, 1.7-25.1; P = .003)
• conjunctival hemorrhage or chemosis (OR, 4.2; 95% CI, 2.2-8.5; P < .001)

Researchers translated the results into a bedside tool and tested it on the validation group. Overall, the algorithm was associated with substantial ocular injury “with a 95% sensitivity (95% CI, 77.2-99.9), 40% specificity (95% CI, 28.9-52.0), 31.8% positive predictive value (95% CI, 27.5-36.5), and 96.8% negative predictive value (95% CI, 81.3-99.5).”

As no method will be 100% sensitive, investigators advise the tool to be used to triage patients, as opposed to specifically screen out individuals. They also suggest any patients who do not earn a high score on the tool should still be scheduled for outpatient follow-up. According to authors, a high sensitivity is the most important factor because delayed care of a substantial ocular injury is more harmful than low specificity.

“Our algorithm only relies on measures of vision that can be performed quickly and without tools at the bedside, and we include drowsy and intubated patients,” researchers wrote. “We find this to be critical to any practical algorithm given that nearly 20% of consults from this study were intubated or drowsy. As a result of these changes, the algorithm works well in the bedside setting and is user friendly for non-ophthalmologists, making it a useful triage tool.”

Retrospectively collected training and test data sets mark limitations to the study. A prospective, longitudinal study of orbital fracture cases seen initially in the emergency setting by non-ophthalmologists is thus warranted to test the algorithm.

Reference

Rossin EJ, Szypko C, Giese I, Hall N, Gardiner MF, and Lorch A. Factors associated with increased risk of serious ocular injury in the setting of orbital fracture. JAMA Ophthalmol. Published online November 25, 2020. doi:10.1001/jamaophthalmol.2020.5108