Retinal detachment and posterior vitreous detachment can present with similar symptoms but the management and prognosis between the two conditions are very different.
While retinal detachment is an ocular emergency, posterior vitreous separation is generally not. Ultrasound of the eye can help diagnose and distinguish between Retinal Detachment and Posterior Vitreous Detachment but an urgent/emergent ophthalmology consult should be placed to definitively differentiate between the two.
If you see a hyperechoic membrane tethered to the optic nerve, this is a retinal detachment. However, if the hyperechoic flap is along the posterior wall of the eye and not tethered to the optic nerve, this could be a retinal detachment or a posterior vitreous detachment.
The table below shows the differences between retinal detachment and posterior vitreous detachment:
| Retinal Detachment | Posterior Vitreous Detachment | |
| Emergency Referral Needed | Yes | No |
| Vision Changes | Constant vision loss | Fluctuating vision blur |
| Optic Nerve Sheath Attachment | Hyperechoic line most often attached to the optic nerve sheath (unless RD is not right next to optic nerve) | Hyperechoic line is not attached to the optic nerve sheath |
| Mobility with eye movements | Less mobile: adheres closely to wall | Very mobile; undulates like “seaweed” |
| Thickness | Thick folded membrane | Thinner, smooth folded membrane |