Here we are again! Drum roll for August’s Ultrasound of the Monthaward, which goes to Dr. Ryan Rees! Please see the fellows for your prize. This patient was a 62 y/o male who presented with new flashers and floaters of the right eye. Visual acuity in the affected eye was 20/70. Dr. Rees astutely grabbed the ultrasound machine, selected the linear probe, adjusted the depth perfectly, and then cranked up the gain appropriately to get a good view into an otherwise deeply anechoic vitreous space.
Clip 1 reveals a mobile hyperechoic tissue band that appears to be anchored laterally and floats above the back of the eye. Extraocular movements cause the band to “wiggle” after the eye has finished moving – a phenomenon called “after movement”. Choroidal detachment will look similar but will have very limited after movement. You’ll notice also in Clip 1 that the optic nerve is mostly not visible. The main differential diagnosis for clip 1 is retinal detachment vs. vitreous detachment (which can appear almost identical). The key differentiating factor is that thevitreous detachments do not necessarily anchor to the optic nerve and will exhibit fairly dramatic after movement for that reason (image below for reference). Clip 2 shows the retina peeling of just lateral to the optic nerve, thereby illustrating one ofthe key anchor points that help make the final diagnosis of retinal detachment. The other anchor “point” for the retina is the ora serrata (anterior margin of the retina that interfaces with the ciliary bodies).
Keep the interesting (and high quality) scans coming!
Your Ultrasound Fellows,
Ian and Alek
Wash U EM Ultrasound Faculty and Fellows