Choroidal Osteoma With Choroidal Excavation Due to Decalcification Five Years After Photodynamic Therapy: A Case Report.

A choroidal osteoma (CO) is a relatively rare, benign tumor with ossification that develops in the choroid and undergoes enlargement and decalcification in its natural course. Photodynamic therapy (PDT) is used to induce decalcification, but there are few reports on individual cases treated with PDT. A 47-year-old Japanese man who had reduced decimal visual acuity (VA) of the right eye to 0.