Vitreous and Retina

Congenital Hypertrophy of the RPE (CHRPE)

Multiple, sharply demarcated hyperpigmented lesions of congenital hypertrophy of the retinal pigment epithelium (CHRPE).
  • Benign pigmented fundus lesions that commonly discovered during routine eye examination.

Clinical Features

  • Usually asymptomatic.
  • Signs:
    • Well-demarcated, round, solitary or multiple gray-brown or black lesions which have flat or scalloped margins.
    • May be encircled by hyper- or hypo-pigmented halo.
    • Depigmented or hypopigmented punched-out lacunae or fenestration lesions may be evident within larger lesions.
    • Multiple areas of grouped CHRPE simulating the animal foot-print are also called "bear tracks".
    • Generally located in the peripheral but may occasionally in the peripapillary region.
  • Fluorescein angiography demonstrates blocked choroidal fluorescence by the hypertrophied RPE and no leakage of dye.
  • Differential diagnosis include: choroidal melanomas, choroidal nevi, melanocytomas of the choroids, hyperplasia of the RPE, post-hemorrhage hemosiderin deposits.
  • Known to be associated with other systemic findings such as familial adenomatous polyposis and Gardner's syndrome (intestinal polyposis, hamartoma of the skeleton, and multiple soft tissue tumors).