A 35-year-old male presented to our ED with complaints of progressive vision loss over the past month. He initially described intermittent dark spots in his vision, but over the past few days his vision had gone completely black in the affected eye. There was no associated pain.
Initial VS: HR 106, BP 190/105, RR 18, Sp02 97% on RA, T 98.2 °F
The affected eye was noted to have a minimally reactive pupil, but was not injected.
The differential diagnosis of painless visual loss included central retinal artery occlusion, central retinal vein occlusion, retinal detachment, vitreous body detachment, and vitreous hemorrhage. The ED team performed a bedside ocular ultrasound seen below to aid in diagnosis.
What do you see?
There is an echogenic flap seen in the posterior chamber. Look how the flap is tethered to the optic disc and then both sides of the eye. This is without doubt a retinal detachment because the retina attaches to the ora serrata anteriorly and the optic disc posteriorly. The retina also looks rather thick. This is seen in chronic detachments.
Here is a normal eye ultrasound for comparison.
Here is a schematic of the structures we are seeing in the ultrasound.
The retina is supposed to adhere to the back of the eye and normally will not be seen with ultrasound.
Ophthalmology did see the patient in the ED and felt this process was chronic and that he would not recover the vision in his affected eye. He interestingly was felt to have panuveitis, which might have caused his detachment. Most patients with retinal detachment, however, present acutely and require rapid diagnosis and treatment to allow for retinal viability.
The sensitivity of bedside ultrasound in detection of retinal detachments is 97-100% and the specificity is 83-100%. We believe that US as a first line investigation is superior to traditional methods and within the scope of practice of emergency medicine
Bottom Line: Ocular ultrasound performed in the ED can quickly and reliably diagnose retinal detachments.
References
- Lyon M and von Kuenssberg Jeble D. Chapter 19: Ocular. Ma and Mateer’s Emergency Ultrasound. 3rd ed. Chicago: McGraw-Hill Education, 2014. 569-586.
- Vrablik ME, Snead GR, Minnigan HJ et al. “The Diagnostic Accuracy of Bedside Ocular Ultrasonography for the Diagnosis of Retinal Detachment: A Systematic Review and Meta-analysis.” Annals of emergency medicine 65 (2): 199–203