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Patterns of retrograde axonal degeneration in the visual system
Willemien A de Vries-Knoppert1, Johannes C Baaijen2, Axel Petzold3,4,5
1Dutch Expertise Centre for Neuro-ophthalmology and Department of Ophthalmology, Amsterdam UMC, Vrije Universiteit Amsterdam, The Netherlands.
Brain : a Journal of Neurology
|August 1, 2019
Summary
This study provides evidence for trans-synaptic retrograde axonal degeneration in the human visual system following temporal lobe resection. Inner retinal atrophy correlated with visual field defects, revealing distinct degeneration patterns potentially targetable for neuroprotection.
Area of Science:
- Neuroscience
- Ophthalmology
- Pathology
Background:
- Acquired trans-synaptic retrograde axonal degeneration (RTD) in the human visual system lacks conclusive evidence.
- Previous studies were limited by anterior visual pathway pathology and neurodegenerative comorbidities.
Purpose of the Study:
- To investigate RTD in the human visual system after partial temporal lobe resection.
- To overcome limitations of prior human studies by focusing on anterior visual pathway integrity.
Main Methods:
- Prospective, longitudinal cohort study involving 25 epilepsy patients undergoing temporal lobe resection.
- Retinal optical coherence tomography (OCT) scans acquired pre- and post-surgery.
- Utilized novel region of interest-specific, retinotopic OCT analysis.
Main Results:
- Significant inner retinal layer atrophy observed in patients with visual field defects.
- RTD affected retinal nerve fibre, ganglion cell, and inner plexiform layers.
- Atrophy rates correlated significantly with resected brain tissue volume and time from surgery.
Conclusions:
- Demonstrated true RTD in the human visual system, distinct from other pathologies.
- Identified three patterns of RTD: direct, rapid self-terminating, and prolonged.
- Prolonged RTD suggests a potential neuroprotective target.
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