Dynamic Magnetic Resonance Imaging Changes in Spinal Ependymomas and Their Impact on Surgical Planning.

Spinal ependymomas are common intramedullary tumors that can show dynamic changes in magnetic resonance imaging findings over time. This study aimed to analyze these imaging changes and their implications for perioperative management. The retrospective study included patients diagnosed with World Health Organization grade 2 spinal ependymoma who underwent surgical resection and had at least 2 preoperative magnetic resonance imaging scans. Patients were divided into 2 groups based on the presence or absence of radiographic changes on magnetic resonance imaging. Magnetic resonance imaging analyses included non-contrast T1- and T2-weighted images, as well as gadolinium-enhanced T1-weighted images when available. Key features evaluated included intraparenchymal edema, hemosiderin deposition, syringomyelia, and cyst components. Changes in tumor size and contrast enhancement patterns were documented. Radiographic changes were identified in 4 out of 15 cases (26.7%). All cases with imaging changes exhibited hemosiderin deposition or hemorrhage, significantly higher than in cases without changes (100% vs. 18.2%, p < 0.05). No significant differences were observed in the presence of cystic components, syringomyelia, or edema between the groups. In the group with radiographic changes, the timeframe for these changes in the images ranged from 3 days to several years. Spinal ependymomas can demonstrate dynamic magnetic resonance imaging changes during the preoperative period, including both growth and reduction in tumor size. The presence of hemosiderin deposition or hemorrhage might be associated with these imaging changes. Proper timing of magnetic resonance imaging is crucial for informing surgical planning and optimizing treatment strategies for patients with spinal ependymomas.