Posterior vitreous detachment
Age-related separation of the vitreous from the retina
Overview
Age-related separation of the vitreous gel from the retinal surface — very common and usually benign. Causes acute flashes and floaters (including a ring floater, the Weiss ring). The essential task is to exclude an associated retinal tear/detachment, since PVD can tear the retina as it separates.
Recognise
- Sudden onset of floaters (often a single large 'cobweb'/ring) and brief flashes of light, usually one eye
- Vision otherwise normal; no field defect
- Common with age and in myopia; may precede a retinal tear/detachment
Red flags
- A SHOWER of floaters, a curtain/shadow, or field loss → suspect retinal tear/detachment — urgent referral
- Vitreous haemorrhage (sudden numerous floaters/reduced vision) accompanying the PVD → urgent
Differentials & how to tell them apart
Investigations
Dilated fundus examination to look for a retinal tear, vitreous pigment (Shafer sign) or haemorrhage; B-scan if no view.
Management
Urgent dilated exam to exclude a tear; reassure if isolated PVD
- 1Arrange assessment by someone competent in slit-lamp + indirect ophthalmoscopy within 24 h (urgent same-day if any field loss or fundoscopic signs of detachment/haemorrhage).Gate: Isolated PVD is benign, but ~10–15% have an associated retinal tear — it MUST be examined and the patient safety-netted, never just reassured by history
- 2Retinal tear found → laser/cryo retinopexy. Otherwise reassure with safety-netting for new field loss/curtain (re-present immediately).
Key points
Flashes + a single new floater with normal vision and field = likely PVD — but you only know after a dilated exam excludes a tear. Safety-net hard.
Monitor & prognosis
Re-present urgently if symptoms escalate (more floaters, curtain).
Benign once a tear is excluded.
Source: NICE CKS Retinal detachment; RCOphth