Early and late inner retinal changes after inner limiting membrane peeling

Area of Science:

• Ophthalmology
• Retinal Surgery
• Microscopic Anatomy

Background:

• Pars plana vitrectomy with inner limiting membrane (ILM) peeling is standard for macular hole and epiretinal membrane surgery.
• ILM peeling can induce mechanical trauma to the retinal nerve fiber layer.
• Recent literature highlights anatomical changes in the macula post-ILM removal.

Purpose of the Study:

• To comprehensively review the literature on anatomical changes in the macula following ILM peeling.
• To detail the sequence and characteristics of these post-operative changes.
• To provide insights for developing less traumatic ILM removal techniques.

Main Methods:

• Literature review of studies reporting macular changes after ILM peeling.
• Analysis of imaging techniques including biomicroscopy, infrared imaging, autofluorescence, and spectral-domain optical coherence tomography (OCT).
• Correlation of imaging findings with surgical procedures and potential underlying mechanisms.

Main Results:

• Earliest change is post-operative swelling of the arcuate retinal nerve fiber layer (SANFL), appearing as hypoautofluorescent striae and hyperreflectant on OCT.
• SANFL is followed by dissociated optic nerve fiber layer defects, appearing as inner retinal dimples on OCT and dark macular spots en face.
• Post-operative foveal displacement may cause temporal thinning and nasal thickening of the macula, with potential peripapillary nerve fiber layer degeneration.

Conclusions:

• ILM peeling, while indicated for specific surgeries, is a traumatic procedure with acute subclinical effects on inner retinal layers.
• Ganglion cells appear unaffected, though the ganglion cell complex may reduce in volume due to Müller cell trauma.
• Further research into these subclinical changes is crucial for advancing minimally traumatic ILM removal methods.