There are some reports of blindness from sinus surgery, but it is extremely rare cases. Sinus problems are annoying. It brings runny nose, congested nasal cavity, watery eyes, swollen eyelids and decreased smell capability. Sinus surgery works by breaking the blockage or remove the excessive tissue in sinuses so that it is easier to get the mucus drained away. Some common side effects from the sinus surgery including bloody discharge or bleeding, nasal or sinus infection, cerebral spinal fluid leakage, blurry vision and oral numbness. Normally speaking, it won't lead to blindness in most cases. But we all know that eyes are very near to nasal cavity. The optic nerves might be damaged by surgical tools during the surgery. In most cases, the damaged optic nerves would cause blurry or double vision, which is normally temporary. In extremely rare cases, the sinus infections might be spreaded to the adjacent tissue such as eyes or brain, leading to vision loss or even death.