Almost all vitrectomy surgeries performed in adults are performed under local anesthetic, and usually in an outpatient operating room.  When the patient arrives an intravenous line is started and the patient is given a sedative prior to the local anesthetic.  Usually a retrobulbar block is performed.  This involves injecting local anesthetic into the orbit, or eye socket, which deadens the sensory nerves and usually the visual nerve as well.  Most patients are not aware of the injection because of the sedative used.  Although patient’s are awake for the procedure, they are not able to see or feel anything and frequently doze off.  However, this is not general anesthesia where a tube is placed in the airway and general anesthetic gasses used to keep the patient asleep.

Most procedures are less than two hours long, and oftentimes much less than one hour long, so prolonged anesthesia and sedation is rarely necessary in adults.

The procedure involves placing three, or sometimes four, cannulas through the sclera, which is the white part of the eye.  These cannulas are small tubes with a very small diameter, the size of a small gauge needle.  The cannulas are so small that stitching the wound is rarely needed when they are removed.  Through these cannulas are placed various instruments including a fiberoptic light pipe to illuminate the inside of the eye, infusion cannulas to keep the eye inflated with solution during the procedure, and other micro instruments to manipulate the retinal tissues.  These can include scissors, suction devices, cauterizing instruments, and grasping instruments.