Intern Ultrasound of the Month: Vitreomacular Traction Syndrome & Diffuse Scleritis
The Case
40yo M with history of poorly controlled types 1 diabetes and diabetic retinopathy presented to the emergency department for a few days of atraumatic left eye irritation and pain exacerbated with extraocular movements. He described a vertical red line in the middle of the visual field of his affected eye. ROS otherwise negative including change in visual acuity, diplopia, flashers, floaters, URI symptoms, fever, chills, nausea, vomiting, headache, focal weakness or paresthesia.
Physical exam was significant for conjunctival injection of left eye, mild proptosis, and a small amount of mucoid discharge. Extraocular movements intact but clearly painful. No obvious foreign body or abrasion. Visual fields full. Intraocular pressure within normal limits. Acuity OS 20/70, OD 20/40.
Point-of-care ultrasound performed on the affected eye and revealed the following:
POCUS findings:
Hyperechoic linear membranes extending from anterior to posterior globe on both medial and lateral aspects. There appear there to be multiple attachment points posteriorly, some near the optic nerve. This was concerning for but different-appearing than typical retinal detachment. The membranes are also less mobile than typical retinal detachment with dynamic exam.
Diffuse scleral thickening, seen anteriorly as well as posteriorly which, along with clinical presentation, was suggestive of scleritis.
Case continued: Ophthalmology was consulted. They performed comprehensive exam including dilated fundal assessment and diagnosed “vitreo-retinal traction bands forming an almost complete napkin ring” + diffuse (anterior + posterior) scleritis. They recommended outpatient ophtho follow up and a course of topical steroids and cycloplegics, along with NSAIDs, in the meantime; opted against systemic steroids until diabetes was better controlled. Also requested initiating inflammatory/rheumatologic workup. Once glucose levels improved, he was discharged home with close follow up.
https://upload.wikimedia.org/wikipedia/commons/8/8a/Three_Internal_chambers_of_the_Eye.png
Vitreomacular Traction (VMT) Syndrome
What is it? —> Incomplete posterior vitreous detachment (PVD) leading to multiple tractional forces at the vitreo-retinal/macular interface, resulting in morphologic changes and often functional effects [1]
Pathophysiology: fibrocellular proliferation of glial cells, macrophages, and fibrocytes at the vitreoretinal interface. Growth factors may also play a role [2-3]
Epidemiology:
Slightly more common in female, no predilection for age or race.
Isolated VMT
Annual prevalence: 22.5/100,000
Annual incidence: 0.6/100,000
However, the majority of cases are concurrent VMT (associated with diabetic retinopathy or macular edema, age-related macular degeneration, other macular diseases) and the prevalence & incidence are much higher [4]
Risk Factors: diabetes, diabetic retinopathy, hypertension, sickle cell, eye surgery, vitreous hemorrhage, retinopathy of prematurity
Complications: potential for retinal detachment and vision loss. Complete vitreous detachment reduces the risk.
Symptoms: usually insidious & may include blurred/reduced/altered vision, scotoma, metamorphopsia, micropsia [3].
Diagnosis: optical coherence tomography (OCT) is standard. Ultrasound useful for identifying partial posterior vitreous detachment.
Management: observation, intraocular enzyme injection, may require vitrectomy [5].
Ultrasound Findings
Hyperechoic membrane within the vitreous that’s less mobile with dynamic exam compared to retinal or vitreous detachment due to traction on the retina. May see traction bands.
Scleritis
What is it? Inflammation and edema of the sclera
Types: Anterior (more common) vs posterior (less common but thought to be underdiagnosed)
Determined by location relative to the extraocular rectus muscles
Associations: more common in females and most often associated with autoimmune disorders, though may also be infectious or trauma/surgically induced
Clinical presentation: eye pain worse with movement. May have scleral edema, erythema, violet-bluish hue if anterior.
Complications: vision loss (particularly if posterior)
Diagnosis: clinical +/- US, MRI
Treatment: NSAIDs —> steroids (topical vs systemic). Immunomodulators if indicated [6]
Ultrasound finding
Thickened sclera > 2mm
Fluid in Tenon capsule —> pathognomonic “T sign” (fluid in the posterior episcleral space on both sides of the optic nerve and extending around optic nerve).
May see swelling of optic disc swelling, distended optic nerve sheath, retinal detachment [7]
Quick Review of Ocular POCUS
Technique
Linear probe (high frequency), probe marker to patient right
Cover eye with tegaderm (remove air bubbles)
Apply a lot of gel. Stabilize hand on pt’s face to control amount of pressure applied.
Identify structures of eye
Turn down the gain to evaluate optic nerve (& structures posteriorly)
Increase gain to better visualize abnormalities within vitreous
Dynamic exam: have patient look side to side
The More Common Pathologies Evaluated with POCUS [8-9]
Retinal detachment - an ocular emergency
Hyperechoic linear structure seen within the vitreous that extends from/is tethered to the optic nerve posteriorly; attachment points shouldn’t cross midline
Mobile/appears like “the wave” w/ dynamic exam; less free-floating than vitreous detach.
Complete retinal detachment forms “V-shape”
Vitreous detachment
Nonemergent, often age-related
Wavy, hyperechoic membrane within the vitreous that’s NOT attached to the optic nerve; often thinner than retinal detachment & can cross over midline.
Free floating, swirls with dynamic exam (washing machine sign)
***Must 1). visualize the optic nerve and 2). perform dynamic exam to differentiate the two
Vitreous hemorrhage
Echogenic collection in the posterior vitreous chamber that moves with kinetic exam. May form membranes if over time.
May be present in isolation or concurrently with RD or VD, facial trauma, coagulopathy, diabetes, CRVO.
Key Points
When evaluating within the vitreous:
Turn up the gain very high. Could miss abnormal findings otherwise.
Must include dynamic exam (having patient look side to side). This is key for picking up intravitreous abnormalities (i.e. retinal or vitreous detachments, hemorrhage, etc) and distinguishing between them.
Visualize the optic nerve to differentiate retinal vs vitreous detachment.
Any attachment to posterior globe near the optic nerve should raise concern for retinal detachment and prompt ophtho evaluation.
Consider POCUS for atraumatic eye pain worse with extraocular movements to look for posterior scleritis, which is best diagnosed with ultrasound. If present, consider an autoimmune process & workup.
POST BY: DR. EVAN WALSH, PGY1
FACULTY EDITING BY: DR. LAUREN MCCAFFERTY
References
Duker JS, Kaiser PK, Binder S, et al. The International Vitreomacular Traction Study Group Classification of Vitreomacular Adhesion, Traction, and Macular Hole. Ophthalmology. 2013;120(12):2611–2619
Jackson TL, Nicod E, Simpson A, Angelis A, Grimaccia F, Kanavos P. Symptomatic vitreomacular adhesion. Retina. 2013;33(8):1503–11.
Bottós J, Elizalde J, Arevalo JF, Rodrigues EB, Maia M. Vitreomacular traction syndrome. J. Ophthalmic Vis. Res. 2012;7(2):148–61.
Jackson TL, Nicod E, Angelis A, Grimaccia F, Prevost AT, Simpson AR et al. Vitreous attachment in age-related macular degeneration, diabetic macular edema, and retinal vein occlusion: a systematic review and metaanalysis. Retina. 2013; 33: 1099–1108.
Steel DHW, Lotery AJ. Idiopathic vitreomacular traction and macular hole: A comprehensive review of pathophysiology, diagnosis, and treatment. Eye. 2013;27(SUPPL):S1-S21.
McCluskey PJ, Watson PG, Lightman S, Haybittle J, Restori M, Branley M. Posterior scleritis: clinical features, systemic associations, and outcomes in a large series of patients. Ophthalmology. 1999; 106:2380-6.
Lavric A, Gonzalez-Lopez JJ, Majumder PD, Bansal N, Biswas J, Pavesio C, Agrawal R. Posterior scleritis: analysis of epidemiology, clinical factors, and risk of recurrence in a cohort of 114 patients. Ocul Immunol Inflamm. 2016;24:6-15.
De La Hoz Polo M, Torramilans Lluís A, Pozuelo Segura O, Anguera Bosque A, Esmerado Appiani C, Caminal Mitjana JM. Ocular ultrasonography focused on the posterior eye segment: what radiologists should know. Insights Imaging. 2016;7(3):351-364.
Ma OJ, Mateer JR, Reardon RF, & Joing S. (2014). Ma and Mateer's Emergency Ultrasound. New York, NY: McGraw-Hill Education