An 80-year-old woman was treated with photodynamic therapy (PDT) to the left eye for polypoidal choroidal vasculopathy (PCV). About 3 months after PDT, her left eye developed a chorioretinal anastomosis with severe atrophy of the retinal pigment epithelium in the macula; visual acuity in this eye was 20/1000. She received a second session of PDT, plus an intravitreal injection of triamcinolone acetonide. About 3 months after the second treatment, the chorioretinal anastomosis was enlarged and the retinal vessels involved in the anastomosis were more dilated. About 1 year after the first PDT, visual acuity in the left eye had stabilized at 20/400. Development of a chorioretinal anastomosis is a distinct possibility following PDT in eyes with PCV, and can lead to poor visual recovery.