Online Articles: Case Report/Small Case SeriesIris Stromal Cyst in a 6-Month-Old With Rapid Progression to Angle ClosureSantos, Matthew C. MD; Lee, Andrew R. MDAuthor Information John Hardesty Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO Disclosure: The authors declare no conflict of interest. Reprints: Andrew R. Lee, MD, 660 South Euclid Avenue, CB 8096, St. Louis, MO 63110 (e-mail: firstname.lastname@example.org). Journal of Glaucoma: October 2020 - Volume 29 - Issue 10 - p e113-e115 doi: 10.1097/IJG.0000000000001630 Buy Metrics Abstract Case Report: A 6-month-old female presented with an iris cyst in the left eye, first identified at age 4 months. The patient was seen by an ophthalmologist at age 6 months and referred for further management. Our examination 2 weeks later demonstrated a 6 mm diameter iris cyst originating from the anterior surface of the inferior iris, occupying the inferior two thirds of the anterior chamber and obscuring the pupil. Intraocular pressure was normal and the remainder of the anterior chamber was formed. Because of concern for the development of amblyopia, the patient was scheduled for an examination under anesthesia and iris cyst removal 2 days later. In the intervening 2 days, the patient’s mother noted worsening photophobia and tearing. At the time of surgery, the intraocular pressure was 51 mm Hg in the left eye. Anterior examination demonstrated interval development of shallowing of the anterior chamber with irido-corneal and cyst-corneal touch. The iris cyst had increased to 8 mm in size and filled the entire pupillary aperture. The iris cyst was excised, and histopathology confirmed the diagnosis of an iris stromal cyst. Conclusions: Congenital stromal cysts of the iris can enlarge, threatening amblyopia and secondary glaucoma in children. Although angle closure is a known theoretical complication of iris stromal cysts, actual cases are rare in the literature. This case demonstrates the importance of serial examinations to monitor progression of iris stromal cysts, particularly in young children. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.