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Updated: Jun 18, 2026
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Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System
Published on: May 12, 2011
Traumatic disruption of the optic chiasm
Laura Segal1, Jella Angela An, Mark Gans
1McGill University Health Centre, Montreal, Quebec, Canada. lsegal2@gmail.com
Summary
Severe head trauma caused a rare complete transection of the optic chiasm, leading to persistent bitemporal hemianopia. This case highlights imaging findings in traumatic optic chiasm injury.
Area of Science:
- Neuroscience
- Ophthalmology
- Radiology
Background:
- Traumatic brain injury can cause visual field defects.
- Optic chiasm injuries are uncommon but can lead to significant vision loss.
Purpose of the Study:
- To document a rare case of complete optic chiasm transection following head trauma.
- To illustrate the utility of serial MRI in visualizing traumatic optic chiasm injury progression.
Main Methods:
- Case report of a 27-year-old male with severe head trauma.
- Serial brain Magnetic Resonance Imaging (MRI) to assess optic chiasm integrity.
Main Results:
- Initial MRI showed hemorrhagic contusion of the optic chiasm.
- Follow-up MRI at 4 weeks revealed complete transection of the optic chiasm.
- The patient presented with persistent bitemporal hemianopia.
Conclusions:
- Complete optic chiasm transection is a rare but possible consequence of severe head trauma.
- Serial MRI is crucial for diagnosing and monitoring traumatic optic chiasm injuries.
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