Optimal management in optic nerve sheath meningioma - A multicentre study and pooled data analysis

Area of Science:

• Ophthalmology
• Radiation Oncology
• Neurosurgery

Background:

• Optic nerve sheath meningiomas (ONSMs) are rare, benign tumors affecting the anterior visual pathway.
• The optimal radiotherapy approach for ONSM management remains undetermined.
• This study investigates visual outcomes across different radiotherapy subtypes for ONSM.

Purpose of the Study:

• To compare visual outcomes and side effects of various radiotherapy techniques in ONSM patients.
• To determine the most effective radiotherapy modality for preserving and improving vision in ONSM.
• To provide evidence-based recommendations for ONSM treatment strategies.

Main Methods:

• Retrospective analysis of 15 ONSM patients treated with radiotherapy between 2000-2016.
• Assessment of visual acuity, visual fields, color vision, OCT retinal nerve fiber layer thickness, and tumor response.
• Pooled data analysis of existing literature using statistical tests (chi-squared, Fisher exact).

Main Results:

• Fractionated radiotherapy significantly improved visual fields (p=0.046), visual acuity (p=0.0017), and color vision (p=0.015) in the cohort.
• Pooled analysis indicated fractionated stereotactic radiotherapy yielded better visual acuity than 3D conformal radiotherapy (p=0.008).
• Stereotactic radiosurgery showed superior visual acuity compared to 3D conformal methods (p=0.035) and equivalent outcomes to other fractionated methods, with lower long-term side effects.

Conclusions:

• Fractionated radiotherapy and stereotactic radiosurgery are recommended for ONSM treatment due to favorable visual outcomes and reduced toxicity.
• 3D conformal radiotherapy is associated with poorer visual results and increased long-term side effects and should not be recommended for ONSM management.
• This study highlights the importance of selecting appropriate radiotherapy techniques for optimizing patient outcomes in ONSM.