Haemoglobin spherulosis: Fine needle aspiration biopsy of an unusual ocular lesion

Objective Haemoglobin spherulosis (HS) is a rare lesion occurring post‐vitreous haemorrhage that is absent from the cytopathology literature. Methods We present the fine needle aspiration (FNA) biopsy cytological features of a case of HS occurring in a 73‐year‐old woman. Results FNA smears of hemorrhagic vitreous fluid showed numerous variably sized smooth glassy spherules ranging from 3‐20 μm. Occasional red cells and a rare lymphocyte were observed, but other cell types were absent. Immunohistochemical staining of a cell block showed diffuse positive staining of spherules with haemoglobin A. Conclusions HS is a rare lesion that occurs post‐subretinal haemorrhage and may be encountered by pathologists examining ocular cytological specimens. Haemoglobin spherulosis is a rare cytological finding that occurs secondary to vitreous haemorrhage. Spherical globules composed of haemoglobin A appear as smooth, rounded, slightly refractile ‘beads’ in cytocentrifugation smears.