Comment on: ‘Peripapillary hyperreflective ovoid mass-like structures—a novel entity as frequent cause of pseudopapilloedema in children’

To the Editor:

Pseudopapilloedema in children, even without symptoms, is a relatively common cause of referral and unnecessary parental anxiety. In their paper, Mezad-Koursh D et al. provide an important contribution to assist in the interpretation of optic disc multimodal imaging in the pediatric age group [1]. The authors include ultrasound B-scan images highlighting a localized hyperechogenic line at the surface of the optic disc, which they have correlated with peripapillary hyperreflective ovoid mass-like structures (PHOMS). I would like to make a few brief remarks on these ultrasound images.

Firstly, it would be useful to know the exact orientation of the probe used to obtain the ultrasound sections. This would help with replication of their method.

In figs. 1–3, the hyperechogenic line at the disc surface, interpreted as representing PHOMS, may be due to dense posterior hyaloid over the disc. A dense posterior hyaloid would be expected in children [2]. This interpretation is supported by the fact that the linear hyperechogenicity appears to be at the inner and central aspect of the disc, whereas PHOMS would be expected to be deeper and peripheral. In fact, in fig. 3, the hyperechogenic line appears over the disc drusen, which is likely calcified, while PHOMS would be expected to be below the level of the apical limit of the drusen. In addition, in fig. 4, the hyperechogenicity also attributed to PHOMS is seen within the substance of the disc, which seems to be contradicting the interpretation of the other images.

By equating the localized superficial disc hyperechogenic line with PHOMS, confusion may arise when the posterior vitreous is being assessed for detachment using ultrasound. It would seem unlikely for PHOMS to be visible on ultrasound imaging, and optical coherence tomography (OCT) is currently the best imaging modality for demonstrating these structures of uncertain significance.

Ultimately, the most important take-home message is to avoid PHOMS misinterpretation as optic disc drusen on OCT, and the authors should be congratulated in disseminating this clinically relevant point.