Peripapillary hyperreflective ovoid mass-like structures—a novel entity as frequent cause of pseudopapilloedema in children

Background Optic nerve head drusen (ONHD) are considered the most common cause for pseudopapilloedema in children. We aimed to investigate and further characterize a new type of optic nerve head lesion on enhanced depth imaging optical coherence tomography (EDI-OCT) named peripapillary hyperreflective ovoid mass-like structures (PHOMS), and ONHD in asymptomatic children with pseudopapilloedema. Methods Retrospective cohort study including 64 eyes from 32 patients with pseudopapilloedema due to PHOMS and/or ONHD. Mean age was 9.0 ± 3.1 years. PHOMS and ONHD were identified and classified on EDI-OCT and infrared images. Ultrasound images were classified for the presence of hyperechogenic structures of the optic nerve head. Results On EDI-OCT, PHOMS were detected in 63 out of 64 eyes (98.4%). In 60 eyes (93.8%), small hyperreflective foci inside the PHOMS were present. In all cases, we identified a new ring sign visible on infrared images, corresponding clearly to the edge of the PHOMS as seen on EDI-OCT. On ultrasound, we describe a new feature of PHOMS appearing as small hyperechogenic structures without posterior shadowing. In 13 eyes (20.3%), ONHD were present on EDI-OCT and ultrasound. Conclusion This is the first study showing that PHOMS are the most common cause for pseudopapilloedema in children. PHOMS is a new entity of optic nerve head lesions. It might be a precursor of buried optic nerve head drusen, which can lead to visual field defects, haemorrhages and CNV. This study offers new tools to identify and follow-up these lesions early in childhood using EDI-OCT.