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Updated: Aug 24, 2026
Characterization of Vascular Morphology of Neovascular Age-Related Macular Degeneration by Indocyanine Green Angiography
Published on: August 11, 2023
A modified technique to stain the internal limiting membrane with indocyanine green
Joerg C Schmidt1, Eduardo B Rodrigues, Carsten H Meyer
1Department of Ophthalmology, Philipps University, Marburg, Germany.
Purpose:
Peeling of the internal limiting membrane (ILM) has improved the outcomes in vitreoretinal surgery of macular diseases. Indocyanine green (ICG) is used to stain and improve the visualization of the ILM. This paper aims to describe a modified approach to stain and peel the ILM avoiding potential adverse side effects.
Methods:
After a core vitrectomy, 0.05 ml of ICG in a concentration of 5 mg/ml is quickly injected under water around the macular region. The tip of the syringe is positioned about 5 mm from the macular tissue, in a way that about a 3-mm diameter area around the fovea is stained by the ICG. Additional ICG is immediately removed by aspiration. Peeling of the ILM is accomplished with a forceps.
Results:
Neither residual ICG in the vitreous cavity nor any clinical signs of phototoxicity like retinal edema were detected in any patients operated by this technique.
Conclusions:
This modified technique to stain the ILM limits the amount and concentration of ICG. The locally limited contact of ICG with the retinal surface seems to be a safe procedure to stain the ILM.
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