Hayat Khan, MS4
The Article:
Vrablik, M. E., Snead, G. R., Minnigan, H. J., Kirschner, J. M., Emmett, T. W., & Seupaul, R. A. (2015). 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.
Background:
Patients commonly present to the emergency department (ED) with ocular complaints. One time sensitive diagnosis that must be identified is retinal detachment (RD). Such patients typically present with sudden onset of floaters and photopsia. Visual acuity and confrontational fields can be performed in the ED, however, a dilated retinal exam with an ophthalmoscope or a slit lamp may not be feasible. Additionally, the view of the retina can further be hindered in patients with dense cataracts or a dense vitreous hemorrhage. As such, an ocular ultrasound may be useful to identify retinal detachment. Currently, there is no consensus on the accuracy of ultrasound for retinal detachment. This meta-analysis aims to explore the diagnostic utility of ultrasound in a diagnosis of retinal detachment.
Clinical Question: Can ocular ultrasound be used to accurately diagnose retinal detachment in the ED?
Design: Systemic review and meta-analysis
Literature search: Ovid MEDLINE, PubMed, EMBASE, the Cochrane Library, Emergency Medical Abstracts, and Google Scholar
Outcomes: Sensitivity and specificity of ocular ultrasound
Inclusion: Three studies with the following inclusions criteria:
Acute vision change (<48 hours) or trauma and also had a confirmatory test
Acute vision change (<48 hours) with ED ultrasound performed before ophthalmology evaluation
Concern for RD and patients received ED ultrasound and ophthalmologic evaluation
Exclusion: Two studies had the exclusion criteria below and one did not state the exclusion criteria
Binocular diplopia, ultrasonography interfered with care
Non-English speakers, unable to consent, known diagnosis
Primary results:
- Three trials that enrolled a total of 201 patients.
- The trials showed a sensitivity of 100%, 100% and 97% and a specificity of 100%, 83% and 92% respectively for detecting retinal detachment
Strengths:
- The authors had a clear clinical question.
- They used multiple databases to find studies that would answer the clinical question.
- Revised Quality Assessment Tool for Diagnostic Accuracy Studies was used to identify adequate studies. It assesses for patient selection, index test, reference standard and flow and timing.
- All three trials were performed in the ED setting.
- The studies were performed in both urban and suburban sites.
Weaknesses:
- The sample size of 3 studies and 201 patients is not very impressive for a meta-analysis.
- One of the studies used fellowship trained sonographers, which may not be representative of the average ED around the country.
- Only one of the trials asked the patients to look in various directions to differentiate retinal detachment from vitreous hemorrhage or vitreous detachment.
- One of the trials did not have ophthalmologist masked to the ED diagnosis, which may have biased their diagnosis.
- Two of the studies had insufficient information to exclude referral bias or spectrum bias, which may have resulted in an overestimation of the sensitivity and specificity.
Author’s Conclusion:
“Bedside ocular ultrasonography can be used to diagnose retinal detachment with a high degree of accuracy. The fundamental utility of ultrasonography and its speed, noninvasive nature, and cost-effectiveness suggest that it is an ideal tool for busy emergency medicine clinicians.”
Our Conclusion:
Bedside ultrasound can be used to accurately diagnose retinal detachment in the ED. It is a quick exam and is an appropriate alternative to a dilated retinal exam with an ophthalmoscope or slit lamp.
Impact to clinical practice:
This study validates the current clinical practice of using ultrasound to identify retinal detachments. An ocular ultrasound should be encouraged for patients presenting with a story concerning for RD.