Altered anterior visual system development following early monocular enucleation.

Area of Science:

• Neuroscience
• Ophthalmology
• Developmental Biology

Background:

• Retinoblastoma is a pediatric eye cancer often requiring enucleation.
• Early enucleation can impact visual pathway development.
• Previous studies focused on late enucleation effects.

Purpose of the Study:

• To determine the long-term morphological consequences of early monocular enucleation on the anterior visual pathway.
• To investigate the impact on the optic chiasm and lateral geniculate nucleus.
• To compare early vs. late enucleation effects.

Main Methods:

• Compared adults with early monocular enucleation to binocularly intact controls.
• Included one late enucleated participant for comparison.
• Evaluated optic nerves, chiasm, tracts, and lateral geniculate nuclei using MRI.

Main Results:

• Early enucleation led to anterior visual system degeneration.
• Optic tract and geniculate volume decreases were less severe contralateral to the remaining eye.
• Late enucleation showed no asymmetry and greater volume loss.

Conclusions:

• Early monocular enucleation results in an asymmetric anterior visual system.
• Altered development may involve neural plasticity mechanisms.
• Balanced binocular input is crucial for normal visual system maturation.