THE CHRYSANTHEMUM PHENOTYPE OF IDIOPATHIC MULTIFOCAL CHOROIDITIS

To describe the clinical characteristics and multimodal imaging features of a distinctive subtype of active idiopathic multifocal choroiditis (iMFC) lesions with grey-yellow chorioretinal lesions surrounded by smaller satellite dots, a presentation referred to as "chrysanthemum lesions."Methods:Retrospective, observational, multicenter case series of eyes with active iMFC and chrysanthemum lesions. Multimodal imaging features were reviewed and presented.Results:Twenty-five eyes from 20 patients (12 women and 8 men), with a mean age of 35.8 ± 17.0 years (range, 7-78 years) were included. Chrysanthemum lesions were equally located in the macula (48.0%) or the mid/far periphery (52.0%). The number of lesions per eye varied from 1 (16.0%) to more than 20 (56.0%). On optical coherence tomography, chrysanthemum lesions showed typical features of iMFC, including subretinal hyperreflective material splitting the retinal pigment epithelium/Bruch membrane. Chrysanthemum lesions were hypoautofluorescent on fundus autofluorescence imaging, hyperfluorescent on fluorescein angiography, hypofluorescent on indocyanine green angiography, and associated with choriocapillaris flow signal deficit on optical coherence tomography angiography.Conclusion:Active iMFC may present with findings resembling chrysanthemum lesions. The distinctive lesion morphology on ophthalmoscopic examination, the large number of lesions, and the high prevalence of exclusive midperipheral and far peripheral involvement may represent a distinctive phenotype of iMFC.