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Posterior Vitreous Detachment

ROUTINE — Retina

Symptoms

  • floaters: sudden "shower" of small spots, cobwebs, or a large central "fly"
  • photopsias (flashes): typically temporal, brief, and more noticeable in dim light
  • blurred vision: often from a floater or hemorrhage crossing the visual axis
  • progression: symptoms usually peak over hours to days

Clinical Findings

Clinical hallmarks

  • weiss ring: a circular glial opacity floating in the vitreous (torn from the optic nerve)
  • shafer's sign ("tobacco dust"): brown rpe pigment granules in the anterior vitreous
  • vitreous hemorrhage: ranging from mild haze to dense blood obscuring the retina

Risk correlations

  • shafer's sign: ~70–90% correlation with a retinal tear
  • vitreous hemorrhage: ~50–70% risk of an associated retinal tear
  • uncomplicated pvd: ~10–15% risk of a retinal tear

Anatomical profile

  • axial myopia (>−6 d) and prior cataract surgery significantly increase risk
  • "falling ash" on oct: hyper-reflective dots in the vitreous suggesting a break

Etiology

Pathophysiology

  • age-related liquefaction (syneresis) of the vitreous gel leads to shrinkage
  • the posterior hyaloid membrane separates from its attachments to the retina

Timeline

  • typically occurs after age 50; the fellow eye usually follows within 6–24 months

Red Flags

  • curtain or shadow: strongly suggests a rhegmatogenous retinal detachment
  • pigmented cells (shafer sign): high probability of an occult retinal tear
  • multiple new floaters + persistent flashes: indicates high traction on the retina
  • dense vitreous hemorrhage: may hide a retinal tear or detachment

Investigations

The gold standard

  • dilated fundus exam with indirect ophthalmoscopy and 360° scleral depression

Slit lamp

  • use 60/90d lens to visualize the hyaloid face and weiss ring
  • examine the anterior vitreous with a high-power beam to check for pigment

Imaging

  • b-scan ultrasound: mandatory if the retina cannot be seen due to hemorrhage
  • oct: confirms the state of the hyaloid attachment at the macula/disc

Treatment

Observation

  • no treatment needed for an uncomplicated pvd with no tears or detachment

Surgical/laser

  • laser retinopexy: for symptomatic horseshoe tears or retinal dialysis
  • pars plana vitrectomy: if dense hemorrhage persists or detachment occurs

Clinical Pearl

ten percent of acute pvds have a retinal tear; fifty percent do if there's vitreous hemorrhage or pigment — scleral depression of the entire periphery is the standard of care, not an optional add-on.

Differential Diagnosis

  • • retinal tear or break (often coexist)
  • • rhegmatogenous retinal detachment
  • • vitritis (posterior uveitis)
  • • asteroid hyalosis (calcium soaps; usually asymptomatic/chronic)

Related Retina Conditions