Increased numbers of mast cells in pterygia.

Purpose/methods: We examined the mast cells in 12 pterygium specimens of patients who underwent primary excisions and the conjunctival specimens of ten normal age-matched control subjects.
Results/conclusion: The mean mast cell count per cubic millimeter was twice as high in the pterygium specimens as in the control specimens. Mast cell proliferation and activation may contribute to the pathogenesis of pterygium formation.