of infection is due to the fact that a foreign object is being introduced into the body. infection can have symptoms of fever and soreness of the neck and shoulders. endoscopic third ventriculostomy an endoscopic third ventriculostomy (etv) is a procedure where an incision is made in the bottom of the third ventricle to make a drainage point for csf to flow out of. the procedure is minimally invasive and is performed endoscopically. the goal in the surgery is to create a path for communication between the third ventricle and the subarachnoid space outside the brain for reabsorption of csf. etv has a higher failure rate than shunting during the first 3 postoperative months, but after this time the risk of failure progressively drops to become half as high as the failure risk for shunting. this treatment does not place a foreign body into the patient so there is a much lower risk of infection as compared to a shunt procedure. along with not implanting a device, this procedure avoids mechanical issues like disconnection, over or underdrainage, and valve dysfunction. the surgery begins by entering the right or left lateral ventricle endoscopically through a burr hole. the third ventricle is identified and entered as well, and an incision is made in the floor of the ventricle and enlarged as necessary with tools such as forceps or fogarty catheters. if a membrane prevents csf flow between the ventricle and the subarachnoid space, then an incision is made in the membrane as well. ideally this procedure can be performed near the midline of the brain with minimal side-to-side motions of the endoscope so as to not tear tissues and cause further complications. research has found that this procedure has a 75% success rate, that 72% of etv surgeries are still correctly functioning after 15 years, and that patients have shorter hospital stays recovering as compared to shunting. if the procedure does not successfully cure the aqueductal stenosis, a second surgery can be performed to enlarge the incision or implant a shunt. problems that can lead to these failures and require additional surgery include the stoma becoming closed or a new membrane forming across the stoma over time. currently there is no universal decision about whether this should be performed in children, as infants have a higher tendency to have a membrane form over the incision which means that an additional surgery would have to be performed.