Objective: To determine the MR (magnetic resonance), pathologic, and clinical findings of extraventricular neurocytoma (EVN).
Study design: Descriptive study.
Place and duration of study: Department of Radiology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China, from January 2020 to March 2022.
Methodology: The MR radiological and pathological data of 11 patients with EVNs proved by histopathology after surgery were analysed retrospectively. Above-mentioned features were studied.
Results: There were 5 men and 6 women, ages ranging from 16 to 56 years. Seven cases (63.6%) were located in the cerebral hemisphere, three cases (27.3%) in the cerebellar hemisphere, and one case in cervical cord. Ten cases (91.0%) were cystic-solid, and one case was predominantly solid with small cystic components. Six cases (54.5%) had mild peritumoural ooedema. The signal was isointense (8/11, 72.7%) or hypointense (3/11, 27.3%) on T1WI, and isointense (1/11, 9.1%) or hyperintense (10/11, 90.9%) on T2WI; all cases showed hyperintense on FLAIR and restricted diffusion on DWI. Haemorrhage was found in two cases (18.2%) and flow-void was found in one case (9.1%). All the tumours demonstrated contrast enhancement.
Conclusion: An accurate diagnosis of EVN is difficult to be made preoperatively. It should be considered when a solid-cystic tumour with the solid part showing isointense on T1WI, hyperintense on FLAIR with mild to moderate enhancement especially restricted diffusion on DWI sequence in patients aged 20-30. When the radiologic manifestations are atypical, more aggressive treatment should be chosen.
Key words: Neurocytoma, Extraventricular, Clinical, Imaging characteristics, MRI.