Filtration Surgeries are the 'special forces' of glaucoma surgery. Their goal is to create a complete, direct bypass—an entirely new drainage pathway—that circumvents the eye's blocked natural drainage system.
What is a Filtering Bleb?
In all filtration surgeries, fluid drains from inside the eye to just beneath the conjunctiva (the clear membrane covering the white of the eye). There, a 'bleb' or 'filtering bleb' is formed where fluid accumulates and is subsequently reabsorbed into the bloodstream. The bleb is usually hidden under the upper eyelid.
When is Filtration Surgery Chosen?
These surgeries are selected for advanced cases of glaucoma, when the required target pressure is very low, or when medical treatments, lasers, and minimally invasive surgeries have failed to halt the disease. Although the recovery is longer and requires close follow-up, these are the most powerful surgeries for achieving significant, long-lasting pressure reduction over years.