Occipital calcified pseudoneoplasms of the neuraxis (CAPNON): understanding a rare pathology

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare and typically benign lesions that can occur anywhere within the central nervous system. Aetiology of this lesion is unclear and surgical removal is usually curative. We present a 24-year-old male patient with a history of occipital migraines who was admitted after sudden onset seizure and loss of vision. CT and MRI demonstrated a small calcifying lesion in the right temporo-occipital lobe. The patient underwent gross total resection of the tumour mass and pathological analysis revealed a CAPNON. The preoperative diagnosis of CAPNON remains difficult due to unspecific radiological findings, yet a clear understanding of characteristic pathological findings and prognosis of CAPNON remains paramount.