Degenerative Myopia

 Degenerative Myopia 

  • Progressive retinal and choroidal degeneration in myopic eyes of at least - 6.00 Diopter refractive errors with an axial length of more than 26 mm.
  • Progressive chorioretinal stretching results in characteristic fundus findings :
    • Optic disc crescent, area of depigmentation due to dragging of the choroids and RPE from the optic nerve
    • Ruptures of Bruch's membrane (lacquer crack)
    • Focal areas of chorioretinal atrophy
    • Localized ectasia involving the sclera, the pigment epithelium and the choroid (posterior staphyloma)
    • Oval with vertical axis and slightly tilted optic disc
    • Localized areas of pigment epithelial proliferation (Foerster-Fuchs spots)
    • Lattice degeneration in the pre-equatorial area may be found
    • Thinning of the RPE and the choriocapillaris give a 'tigroid' or 'tesselated' fundus appearance

Complications:

  • Earlier onset posterior vitreous detachment
  • Small macular hemorrhage
  • Macular hole
  • Posterior retinal detachment
  • Choroidal neovascularization (CNV)
  • Fluorescein angiogram is helpful to reveal choroidal neovascularization.

Management:

  • Laser photocoagulation for selected cases of CNV
  • Posterior scleral buckling for posterior retinal detachment