For many emergency physicians, the eyeball remains a bit of a black box. It comes down to the fact that the standard tools we were introduced to in medical school and residency either feel too rudimentary (the fundoscope) or potentially overwhelming (the slit lamp). It can feel perplexing for many of us to make a definitive diagnosis for patients who come in complaining of “blurry vision,” which can mean different things to so many patients. Even the painful red eye or painless vision loss has a slew of possible diagnoses to consider.

However, with a bit of knowledge and practice, point-of-care ultrasound (POCUS) opens up that black box and has the power to demystify some of those diagnoses emergency physicians were previously at the mercy of an ophthalmologist and a dilated exam to ascertain. For certain eye complaints in particular, POCUS can elevate our diagnostic prowess even further.

Painless Vision Loss

One of the simplest and most definitive utilities for ocular implementation of POCUS is when evaluating for potential retinal pathology. POCUS doesn’t just perform well here—it is one of the few tests that actually has a remarkable ability to rule out pathology, boasting a sensitivity of around 95 percent for retinal detachment across multiple studies and meta-analyses.^1,2 This means it is fast, simple, and makes a diagnosis that no fundoscope, slit lamp, or CT scanner ever could. Your ophthalmology colleagues will thank you.

For the patient presenting with painless vision loss, a monocular field cut, or flashes and floaters, assessing for retinal detachment, vitreous detachment, and vitreous hemorrhage is simple. Start by applying plenty of gel to the closed eye and consider forgoing the transparent film dressing (Tegaderm) when possible.3 Scan through the globe in both the transverse and sagittal planes and then perform the kinetic exam, in which the probe is held stationary while the patient looks in all directions.

The clinician should rest a portion of their hand on the patient’s nose or forehead for stability and to avoid placing too much pressure. An exam should be performed in transverse and sagittal, sweeping through in both directions. A kinetic exam can then be performed in one orientation to evaluate for movement or swirling artifacts such as detachments, hemorrhages or lens dislocations. (Photo Eliana Griego, MD. Click to enlarge.)

Retinal detachments are typically thick, hyperechoic linear defects seen attaching to the back of the retina, and at times appear tethered to the optic disc, whereas vitreous detachments are thinner, more mobile, and “float” over the optic disc. Meanwhile, vitreous hemorrhages have a characteristic appearance of debris in the posterior chamber, which will move around during the kinetic exam, dubbed the “washing machine” sign.