Internal jugular vein (IJV) is the main pathway of cerebral venous drainage and it has valve system to prevent retrograde blood flow to the brain. Anatomical studies revealed that bicuspid or tricuspid valves were located in both jugular veins 2 cm above the subclavia-jugulars bifurcation and 7-18% of the valves were incompetent. IJVV incompetence (IJVVI) may result in retrograde flow which leads to brain congestion and increase of intracranial pressure, which can cause brain dysfunctions in some patients. IJVVI has been reported to be associated with transient global amnesia (TGA), cough syncope, exertional headache, transient ischemic attack, and air embolism. Demographic data are associated with the development of IJVVI. Akkawi et al. demonstrated that old age over 50 years and male gender are the risk factors for IJVVI. A few physiologic conditions are related with IJVVI including elevated intra-thoracic and intra-abdominal pressure, and pulmonary hypertension. Robot assisted laparoscopic prostatectomy (RLP) is one of the most common robotic surgery because of its significant benefits such as smaller incision, less severe postoperative pain, less intraoperative bleeding, and shorter hospital stay compared to traditional radical prostatectomy. The patients undergoing RLP are mostly over 60 years old, have neurologic, cardiac and pulmonary comorbidities. For RLP, patients are in Trendelenburg position most of the time during surgery, which could cause increases in intra-abdominal and intrathoracic pressure.

Inclusion Criteria:

• over 50 years old
• ASA class I or II
• Scheduled for robot assisted laparoscopic prostatectomy

Exclusion Criteria:

• previous neurologic deficit
• history of psychiatric disease, alcoholism or other drug dependency
• Serious hearing or visual impairment or any other comorbidities which would preclude neuropsychological tests

Patients who were over 50 years old with ASA class I or II, scheduled for robot-assisted laparoscopic prostatectomy