Vitreous opacities

• floaters ( entopsia)
  • are formed due to images shed on the retina by opacities in the vitreous
  • can be caused by different types of vitreous opacities like (1)
    • red blood cells
    • inflammatory cells
    • tumor cells
    • amyloid
  • they may cause a localised and faint impediment to sight
  • present as fine dots,cobwebs,veils,strings or clouds (2)
  • their perception depends on the following characteristics:
  • size of the opacities
  • optical density
  • distance from the retina
  • pupil size
  • background (1)
  • may be perceived to move as the opacities move within the vitreous
    • e.g ocular movements
  • they may occasionally be the prelude to a retinal detachment

Reference:

• (1) Margo ,et al. Posterior vitreous detachment, how to approach sudden-onset floaters and flashing lights. Postgraduate medicine 2005;117 (3)
• (2) Gariano RF et al. Evaluation and management of suspected retinal detachment. American Academy of Family Physicians.