Silicone oil droplets in the schlemm’s canal: A surprise during prolene hemi-gonioscopy-assisted transluminal trabeculotomy (hemi-gatt)

Aim and objective: To report a case with emulsified silicone oil (SO) droplets in the Schlemm’s canal (SC), encountered during prolene hemi-gonioscopy-assisted transluminal trabeculotomy (hemi-GATT). Background: In cases with a history of previous pars plana vitrectomy (PPV) with SO tamponade and then SO removal; glaucoma might occur secondary to the presence of emulsified SO droplets. Minimal invasive glaucoma surgeries targeting trabecular meshwork such as GATT surgery might be an ideal treatment option in these cases. Case description: A 57-year-old man presented with uncontrolled intraocular pressure (IOP) and topical anti-glaucoma drug intolerance in his left eye. The patient had a history of PPV with SO tamponade and then intravitreal SO removal 5 years ago. He had a history of Ahmed glaucoma valve (AGV) implantation 2 years ago for the treatment of secondary glaucoma but he was still using topical anti-glaucoma medication. However, IOP was measured as 17 in the left eye. Hemi-gonioscopy-assisted transluminal trabeculotomy was performed successfully to get the patient off medication. During the surgery, SC was full of SO droplets. Conclusion: The presence of SO droplets in the SC might contribute to the development of secondary glaucoma after PPV and SO removal. This might be another surgical indication for GATT surgery in these risky eyes.