[Retrograde degeneration of visual pathway]
N M Eliseeva1, N K Serova1, D I Pitskhelauri1
1Burdenko Neurosurgical Center, Moscow, Russia.
Zhurnal Voprosy Neirokhirurgii Imeni N. N. Burdenko
|December 24, 2021
Summary
Optical coherence tomography (OCT) reveals that ganglion cell layer (GCL) thinning indicates retrograde degeneration in the visual pathway. This degeneration is detectable after damage to the optic nerves, chiasm, or retro-genicular pathways.
Area of Science:
- Ophthalmology
- Neuroscience
- Medical Imaging
Background:
- Retrograde degeneration of the visual pathway can occur at various levels.
- Optical coherence tomography (OCT) is a valuable tool for examining these changes.
Purpose of the Study:
- To assess OCT-derived data on retrograde degeneration in the visual pathway.
- To correlate visual pathway damage location with GCL thinning.
Main Methods:
- OCT was used to measure ganglion cell layer (GCL) thickness in 79 patients with diverse visual pathway lesions.
- Patients included those with traumatic optic nerve/chiasm damage, retro-genicular damage, temporal lobe epilepsy surgery, and occipital lobe lesions.
- Standard visual acuity, perimetry, and brain imaging (MRI/CT) were also performed.
Main Results:
- GCL thinning was observed in 20/21 patients with anterior visual pathway damage within 22 days.
- GCL thinning occurred in 25/58 patients with retro-genicular damage, with detection times of 3 months (temporal lobe epilepsy surgery) and 5 months (occipital lobe lesions).
Conclusions:
- Retrograde degeneration of the visual pathway leads to GCL thinning.
- The timing and occurrence of GCL thinning are dependent on the location of the visual pathway lesion.
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