ORIGINAL PAPER Ophthalmic histiocytic lesions: a baseline demographic and clinicopathological study of 28 cases from two eye centers Hind M. Alkatan . Tariq A. Alzahem . Azza M. Y. Maktabi Received: 14 February 2021 / Accepted: 21 October 2021 Ó The Author(s), under exclusive licence to Springer Nature B.V. 2021 Abstract Purpose Ophthalmic histiocytic lesions comprise a heterogeneous rare group of disorders that are char- acterized by an abnormal proliferation of histiocytes and may affect all age groups of both sexes. The aim of this study was to highlight the basic demographic, clinical, and histopathological characteristics of this rare group of diseases in ophthalmic practice, which has not been previously studied in this area. Only individual cases have been previously reported. Methods This was a retrospective study of all biopsied ocular and periocular histiocytic lesions from two centers, King Khaled Eye Specialist Hospital (KKESH) and King Abdulaziz University Hospital (KAUH) in Riyadh, Saudi Arabia, from January 1993 to December 2018. The histopathological diagnosis was confirmed, and the cases were re-classified by reviewing all histopathological slides. The corre- sponding demographic and clinical data were ana- lyzed. A relevant literature review was also carried out for comparison of our collected analyzed data to published data and to draw our own conclusions. Results A total of 34 ocular/periocular histiocytic lesions in 28 patients who were mostly Saudis (92.9%) were included. The male-to-female ratio was 4:3. The median age at presentation was 6.4 years (range: 2.8–35 years). Twenty-two patients had unilateral involvement, and six patients had bilateral lesions. In patients with Langerhans cell histiocytosis (LCH; L group), the most common presenting findings were eyelid swelling (75%), periocular tenderness (37.5%), proptosis/globe displacement (37.5%) eyelid ery- thema (25%), and orbital pain (12.5%). In patients Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/ s10792-021-02108-1. H. M. Alkatan (&) Á T. A. Alzahem Ophthalmology Department, College of Medicine, King Saud University, P.O. Box: 266, Riyadh 11362, Saudi Arabia e-mail: hkatan@ksu.edu.sa; hindkatan@yahoo.com H. M. Alkatan Á T. A. Alzahem King Saud University Medical City, King Saud University, Riyadh, Saudi Arabia H. M. Alkatan Pathology and Laboratory Medicine Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia T. A. Alzahem Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia A. M. Y. Maktabi Pathology and Laboratory Medicine Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia 123 Int Ophthalmol https://doi.org/10.1007/s10792-021-02108-1