Gangliogliomas involving the optic chiasm

Area of Science:

• Neuro-oncology
• Ophthalmology
• Neuropathology

Background:

• Gangliogliomas are typically low-grade tumors, often affecting the temporal lobe.
• Optic chiasm involvement by gangliogliomas is rare, with varied potential origins and spread patterns.
• Understanding the diverse mechanisms of chiasmal invasion is crucial for diagnosis and management.

Observation:

• Three patients presented with gangliogliomas involving the optic chiasm through distinct pathways.
• Tumor origins included temporal lobe extension, intrinsic hypothalamic/chiasmal growth, and optic tract involvement with lateral compression.
• Clinical presentations ranged from severe bilateral visual loss to stable bitemporal hemianopsia.

Findings:

• Unusual presentations included medial spread from the temporal lobe with spinal cord dissemination and intrinsic hypothalamic/chiasmal tumors.
• Despite radiotherapy, one patient experienced continued visual decline, indicating variable treatment response.
• The diverse mechanisms of optic chiasm involvement contribute to a variable long-term visual prognosis.

Implications:

• This case series underscores the rarity and diverse etiologies of gangliogliomas affecting the optic chiasm.
• The varied visual outcomes emphasize the importance of tailored treatment strategies and long-term monitoring.
• Further research into the specific biological behavior and optimal management of chiasmal gangliogliomas is warranted.