Marfan Syndrome

  • Autosomal dominant disorder marked by tallness and long limbs
  • Caused by mutation in FBN1 gene responsible for elastic fiber strength
  • Chief concern: heart valve degeneration, aortic aneurysm, aortic dissection
  • Principal ophthalmic manifestation: dislocated crystalline lens ("ectopia lentis")
  • Dislocated crystalline lens in 80% of cases
  • Usually dislocated superotemporally
  • Dislocation visible only with slit lamp biomicroscopy through dilated pupil, which shows...
  • Exposed lens zonules: elastic fibers extending radially toward the lens margin and suspending the lens from the ciliary muscle like a hammock
  • Direct trauma to eye, which can cause lens dislocation
  • Homocystinuria, but lens dislocation is inferonasal
  • Refer patients with suspected Marfan syndrome for ophthalmological examination
  • Marked lens dislocation may create blurred vision, so that...
  • Lens extraction necessary if optical measures do not work
  • Retinal detachment and glaucoma may occur independently of lens dislocation