To report a case of recurred iris cyst 11 years after treatment with endodiathermy, which was treated with laser photocoagulation and cystotomy followed by intraocular pressure elevation and underwent anterior chamber irrigation.

A 46-year-old female presented to our department with decreased vision in her left eye that had persisted for several months. The patient had a history of surgical removal of an iris cyst with endodiathermy 11 years ago. Slit lamp examination showed an iris cyst adjacent to the nasal corneal limbus. The cyst was filled with turbid fluid. It distorted the pupil and threatened visual axis. Iris cystotomy (diameter larger than 500 µm) was done with diode laser photocoagulation and a neodymiumdoped yttrium aluminium garnet laser. At the same day, the patient's intraocular pressure elevated to 50 mm Hg in spite of maximal conservative treatment and went through anterior chamber irrigation. After six months, the iris cyst was adhered to corneal endothelium and disappeared. Visual acuity and intraocular pressure was within normal range.

An iris cyst can recur after treatment with endodiathermy. Recurred iris cyst can be successfully treated with laser photocoagulation and cystotomy. However, turbid fluid inside the cyst may outflow to the anterior chamber and cause secondary ocular hypertension after treatment, so careful observation is needed.