1. History
  2. Exam
  3. Photos
  4. Diagnosis
  5. Teaching Points
  6. Comments

Case 94 Diagnosis

Cone dystrophy with supernormal rod electroretinogram

Differential Diagnosis

  • Cone dystrophy: may have bulls-eye maculopathy, central scotoma, and maintain full isopters on Goldmann visual field testing, but lacks a supernormal maximal stimulation response on electroretinogram
  • Cone-rod dystrophy: cone and rod responses on electroretinogram are diminished, even under maximal stimulation conditions. Progressive contraction of isopters on Goldmann visual field testing over time.
  • Neuronal ceroid lipofucinosis: may have bulls-eye maculopathy, but associated with progressive neurologic deficits and seizures.
  • Stargardt disease: may have bulls-eye maculopathy, but typically also has pisciform flecks and characteristic “dark choroid” sign on fluorescein angiography
  • Hydroxychloroqine toxicity: may have bulls-eye maculopathy, but typically older patient with history of hydroxychloroquine use.
Last Modified: Tuesday, 05-Aug-2008 12:05:12 EDT