Orbital Evidence
POCUS Evidence Atlas - ocular eye and orbit. intracranial pressure. EBM review and resource of POCUS for echo diagnosis. Sensitivity Specificity positive and negative likelihood ratios.
The Evidence Atlas: Orbital
This was a prospective, multi-center study conducted at 2 academic emergency departments (ED) and 2 county hospital EDs (n = 225) to evaluate the accuracy of POCUS for diagnosing retinal detachment (RD), vitreous hemorrhage (VH), and vitreous detachment (VD). Each hospital recruited patients presenting to the ED with symptoms of blurry vision, flashers/floaters, and vision loss, whom required emergent ophthalmologic consultation; patients with ocular trauma or suspected globe rupture were excluded. Reference standard was attending ophthalmologists’ final diagnosis masked to POCUS results. Exams were performed by seventy-five unique providers including seventy emergency physicians of varying training level and 5 physician assistants. Study findings demonstrate that the utility of ED POCUS in the diagnosis for RD and VH were quite sensitivity and specific. The utility of POCUS in the diagnosis of VD was less sensitive (42.5%) but remained specific (96%). Overall, ocular POCUS by ED providers is a very good test to both rule-in and rule-out the emergent diagnosis of RD. The use of ocular POCUS is not as good of a test to rule-in or rule-out less emergent diagnoses of VD and VH but provides useful adjunct information to support evidence for those diagnoses. PMID: 30977855 - Reviewed by Dr. Jaclyn Walker
This was a prospective, multi-center study conducted at 2 academic emergency departments (ED) and 2 county hospital EDs (n = 225) to evaluate the accuracy of POCUS for diagnosing retinal detachment (RD), vitreous hemorrhage (VH), and vitreous detachment (VD). Each hospital recruited patients presenting to the ED with symptoms of blurry vision, flashers/floaters, and vision loss, whom required emergent ophthalmologic consultation; patients with ocular trauma or suspected globe rupture were excluded. Reference standard was attending ophthalmologists’ final diagnosis masked to POCUS results. Exams were performed by seventy-five unique providers including seventy emergency physicians of varying training level and 5 physician assistants. Study findings demonstrate that the utility of ED POCUS in the diagnosis for RD and VH were quite sensitivity and specific. The utility of POCUS in the diagnosis of VD was less sensitive (42.5%) but remained specific (96%). Overall, ocular POCUS by ED providers is a very good test to both rule-in and rule-out the emergent diagnosis of RD. The use of ocular POCUS is not as good of a test to rule-in or rule-out less emergent diagnoses of VD and VH but provides useful adjunct information to support evidence for those diagnoses. PMID: 30977855 - Reviewed by Dr. Jaclyn Walker
This was a prospective, multi-center study conducted at 2 academic emergency departments (ED) and 2 county hospital EDs (n = 225) to evaluate the accuracy of POCUS for diagnosing retinal detachment (RD), vitreous hemorrhage (VH), and vitreous detachment (VD). Each hospital recruited patients presenting to the ED with symptoms of blurry vision, flashers/floaters, and vision loss, whom required emergent ophthalmologic consultation; patients with ocular trauma or suspected globe rupture were excluded. Reference standard was attending ophthalmologists’ final diagnosis masked to POCUS results. Exams were performed by seventy-five unique providers including seventy emergency physicians of varying training level and 5 physician assistants. Study findings demonstrate that the utility of ED POCUS in the diagnosis for RD and VH were quite sensitivity and specific. The utility of POCUS in the diagnosis of VD was less sensitive (42.5%) but remained specific (96%). Overall, ocular POCUS by ED providers is a very good test to both rule-in and rule-out the emergent diagnosis of RD. The use of ocular POCUS is not as good of a test to rule-in or rule-out less emergent diagnoses of VD and VH but provides useful adjunct information to support evidence for those diagnoses. PMID: 30977855
This was a systematic review, which including 12 studies (n = 478) using ultrasound measurement of optic nerve diameter (cut point of 5 mm for adult studies, 4.5 mm for age 1–17 years, and 4 mm for age <1 year) to evaluate for increased intracranial pressure (ICP). There was moderate to high heterogeneity among these studies given multiple patient populations. This resulted in wide confidence intervals: sensitivity of 95.6% (95% CI, 87.7%–98.5%), specificity of 92.3% (95% CI, 77.9%–98.4%), positive likelihood ratio of 12.5 (95% CI, 4.2–37.5), and a negative likelihood ratio of 0.05 (95% CI 0.016–0.14). It is also important to mention that the gold standard in this review was CT, which is not as accurate as invasive ICP monitoring. Overall their conclusions were that ocular sonography had a very low LR- (0.05) making it a good test for ruling out raised ICP in a low-risk group, and a high LR+ (12.4) making it a good test for ruling in raised ICP in a high-risk group.
PMID: 26112632
Here a hyperechoic linear density is seen arising from the location of the fundus, indicating retinal detachment. Posterior vitreous detachment and vitreous hemorrhage can look similar to retinal detachment. Given the imminent risk of blindness in these conditions it is essential to identify them as soon as possible. POCUS is an excellent way to do so given the time and skills required to perform a proper fundoscopic exam. Literature has shown sensitivity for this test to be 97-100% and specificity 83-100%. So next time ask yourself... is your fundoscopic exam that good?
Sukh Singh, MD
65 y/o F PMH DM with sudden onset flashes of light and floaters followed by progressively worse blurred vision in her right eye. She has history of cataracts surgery as well as DM retinopathy. POCUS of affected eye shows a prominent hyper-echoic linear density floating freely above the posterior fundus as shown.
Retinal Detachment is considered one of few emergencies whereby the retina becomes detached from the choroid. Once separated from the choroid’s blood supply, retinal ischemia ensues which can result in complete blindness in the affected eye. Salvage of such a potentially devastating injury relies on quick and efficient diagnosis with subsequent referral to definitive care.
Bedside ultrasound has been shown to be 100% sensitive as a screening tool for RD [AEM 2010 Sep;17(9):913-7]. Have patient close eye and place liberal amount of gel either directly over eye or atop a tegaderm dressing. Use a linear probe and scan eye in axial plane to reveal findings demonstrated above.
Dr. Eric Roseman - Kings County Emergency Medicine
Retinal detachment in a patient with 1 day of a right sided visual field cut.Literature has shown sensitivity for this test to be 97-100% and specificity 83-100%. So next time ask yourself... is your fundoscopic exam that good?
Dr. William Scheels
47 y/o M with coronary artery disease on aspirin/clopidogrel with 4 days of decreased vision in his right eye. POCUS demonstrates swirling, amorphous echogenicities known as "the washing machine sign." If the eye remains still the blood will settle with gravity.
Fundoscopic evaluation by ophthalmology confirmed the diagnosis of vitreous hemorrhage.
Dr. Matthew Riscinti and Dr. Taylor Conrad - Kings County/SUNY Downstate Emergency Medicine
Elevated intracranial pressure can be assessed reliably with POCUS.
Find the optic nerve and measure 3mm back from the posterior globe. From here measure the optic nerve from inner wall to inner wall. the normal width is < 5 mm.
A systematic review and meta-analysis found POCUS has a sensitivity of 96% and specificity of 93% for increased intracranial pressure. J Ultrasound Med. 2015 Jul;34(7):1285-94. doi: 10.7863/ultra.34.7.1285.
Dr. Matthew Riscinti - Kings County/SUNY Downstate Emergency Medicine - Image from the Department of Emergency Ultrasound
