Astigmatism

 Astigmatism post penetrating keratoplasty is satisfactorily corrected with contact lens.

Symptoms:

  • Limited visual acuity despite clear corneal graft.

Causes:

  • More frequently occurs in eyes with pre-operative keratoconus, severe scaring, or corneoscleral defect.
  • Irregular suture placement, uneven suture tightness or technical error during the corneal button trephination.
  • Sometimes donor astigmatism.

Management:

  • Suture manipulation or removal for tension redistribution.
  • May be corrected with eyeglasses or contact lenses.
  • In cases where refractive corrections do not provide satisfactory vision due to high residual astigmatism, a variety of surgical options may be employed such relaxing incisions, compression sutures, excimer laser photoastigmatic refractive keratectomy or LASIK.