The Desmarres has a flat, spoon-shaped blade that doctors hold in their hand, giving them full control over how much they pull back the eyelid. Many models have small holes in the blade that help drain tears and fluids during surgery, plus they grip the tissue better than plain smooth tools. Other retractors like speculums use springs or wires to hold both eyelids open at once, but this one lets your doctor adjust pressure and position as needed during the procedure.