Calcified cystic lesion in cerebellum: A case report

Intracranial epidermoid cysts are benign, slow-growing congenital tumors of ectodermal origin. They are rare embryonal benign cystic masses with an incidence rate of approximately 0.04%-0.6% of intracranial tumors. Computed tomography (CT) and magnetic resonance imaging (MRI) are fundamental diagnostic tools providing valuable information for surgical management. We reported a 59-year-old male patient with right limb weakness twelve hours prior to admission, slurred speech, and paresis of the facial nerve. Based on history taking, physical examination, and radiology examinations, we concluded a diagnosis of non-communicated hydrocephalus due to a right cerebellar intra-axial tumor with a suspicion of low-grade glioma (Pylocitic Astrocytoma). CT and MRI in intracranial epidermoid cysts are fundamental diagnostic tools for diagnosing and obtaining helpful information for surgical planning. Intracranial epidermoid cysts appear as lobulated lesions filling and expanding CSF spaces and exerting a gradual mass effect, insinuating between structures and encasing adjacent nerves and vessels. In this case, we noted a hypodense lesion with irregular calcifications and well-defined on the right cerebellar region measuring 6.15 × 5.47 × 5.7 cm, surrounded by a hypodense image suggesting an intra-axial mass suspected of low-grade glioma with a differential diagnosis of brain abscess. The hypointense lesion on the T1WI sequence found in the MRI examination, with no significant contrast enhancement and restricted diffusion area on DWI, was one of the notable features described in the epidermoid cyst. Intracranial epidermoid cyst rarely occurs in the intracranial, resulting in many symptoms in this case, which should be diagnosed and treated promptly. Imaging aids in proper diagnosis and provides more valuable information for further treatment.