Sialidosis is a rare autosomal-recessive lysosomal storage disease characterized by the progressive accumulation of sialyloligosaccharides in the tissues, especially in the brain and in the retinal nerve fibers [
2,
3]. Both forms of sialidosis identified so far (ST-1, ST-2), are due to mutations of NEU1 gene located on 6p21.33, which result in a deficit in the activity of the lysosomal enzyme neuraminidase, and consequent accumulation of sialyl oligosaccharides [
1]. We have described, for the first time, a case of BP in a young patient with ST-1. The Bergmeister’s papilla is is a rare congenital anomaly of the optic disc, characterized by the persistence of residues of the hyaloid artery on the optic disc, in the form of an epipapillary glial membrane, which can occlude the papilla or part of it, making it sometimes difficult to visualize. In healthy fetuses, the hyaloid artery which is responsible for the vascularization of the crystalline lens during embryo development through the Cloquet’s canal, progressively regresses from 10 weeks of gestation, until it disappears at birth. Failure to regress the hyaloid artery can be partial or complete; the residue of the anterior portion on the posterior lens capsule is called Mittendorf’s dot, while the posterior residue on the optic disc is called Bergmeister’s papilla, and is usually made up of glial tissue. Complete persistence of the hyaloid artery extending from the papilla to the lens, which could cause sudden vitreous bleeding, is very rare. BP, in most cases, is an occasional finding, which has no clinical impact. However, in the most severe forms it can be associated with cataracts, persistence of the primitive vitreous, microphthalmia, vitreous hemorrhages and sometimes tractional retinal detachment, due to contraction of the residual fibrovascular tissue [
11‐
13]. Therefore, in case of suspected BP, careful monitoring of eventual vitreous thickening in the peripapillary areas, both by examining the ocular fundus, and especially by SD-OCT, is of considerable importance. In this case report, despite the difficulty of execution, the role of SD-OCT has been fundamental, to identify a hyperreflective opacity as a cap on the left optic disc, remnant of fetal vasculature, with adjacent vitreo-retinal adhesion, that must be monitored. Therefore, our case underlines the importance of performing SD-OCT in neurological pathologies characterized by cherry-red macular spot such as sialidosis, allowing to better visualize a congenital anomaly of the optic disc, not clearly visible with ocular fundus examination alone. Similar cases presenting remnant hyaloid artery should be monitored over time being a possible cause of future visual deterioration.