Association of quantitative radiomic shape features with functional outcome after surgery for primary sporadic dorsal spinal meningiomas

Abstract

Objective: Spinal meningiomas (SM) account for 25%-46% of all primary spinal tumors and show an excellent long-term disease control in case of complete resection. Therefore, the postoperative functional outcome is of high importance. To date, reports on dorsally located SM are scarce. Moreover, the impact of radiomics shape features on the functional outcome after surgery for primary dorsal SMs has not been analyzed yet.

Methods: We retrospectively performed an analysis of shape-based radiomic features in 3D slicer software and quantified the tumor volume, surface area, sphericity, surface area to volume ratio and tumor canal ratio. Subsequently, we evaluated the correlation between the radinomic parameters and the postoperative outcome according to Modified Japanese Orthopedic Association (mJOA) score.

Results: Between 2010 and 2022, we identified 24 Females and 2 Males operated on dorsal SMs in our institutional database. The most common SM localization was thoracic spine (n = 20), followed by cervical (n = 4), and lumbar (n = 2). The univariate analysis and the receiver operating characteristic (ROC) analysis showed a strong diagnostic performance of sphericity in the prediction of postoperative functional outcome based on mJOA score (AUC of 0.79, sphericity cut-of value 0.738; p = 0.01). Subsequently, the patients were divided into two groups (mJOA improved vs. mJOA stable/worsened). Patients with improved mJOA score showed significantly higher sphericity (0.79 ± 0.1 vs. 0.70 ± 1.0; p = 0.03). Finally, we divided the cohort based on sphericity (<0.738 and ≥0.738). The group with higher sphericity exhibited a significantly higher positive mJOA difference 3 months postoperatively (16.6 ± 1.4 vs. 14.8 ± 3.7; p = 0.03).

Conclusion: In our study investigating primary sporadic dorsal SMs, we demonstrated that a higher degree of sphericity may be a positive predictor of postoperative improvement, as indicated by the mJOA score.

Keywords: functional outcome; shape; sphericity; spinal meningioma; surgery.

Figure 1

(A,D) illustrates a regularly shaped dorsal primary sporadic SM with the shape-based radiomic features tumor volume, surface area, sphericity, and surface-area-to-volume ratio, whereas (B,E) show an irregularly shaped dorsally located primary sporadic SM. Illustratory cases of tumor segmentation with 3D-Slicer (version 5.2.1, Surgical Planning Laboratory, Harvard University, US). (C,F) show a regularly shaped dorsal primary sporadic SM with the 3D volume and the corresponding axial T1-gadolinium enhanced sequence.

Figure 2

Receiver-operating characteristic curve (ROC) illustrating the ability of sphericity in the association with mJOA development within 3 months after surgery for dorsal primary sporadic spinal meningioma.

Figure 3

Truncated violin-plots displaying sphericity in patients with mJOA improvement (green) and with stable/worsened mJOA (red). Median values are presented by the thick black lines (p-values of the Student's t-test).