Robot-assisted laparoscopic radical prostatectomy (RALRP) has gained popularity during the past decade and has widely replaced conventional open prostatectomy in many institutions due to reduced blood loss, nerve sparing, less postoperative pain and shorter hospital stay. However, laparoscopic surgery is performed with intraperitoneal carbon dioxide insufflation, which leads to increased intraocular pressure (IOP). In particular, robot-assisted laparoscopic radical prostatectomy (RALRP) usually requires a steep Trendelenburg position and often prolonged insufflation times, which is known to effect the increase in IOP during surgery and may result in ophthalmic complications such as postoperative vision loss (POVL). The majority of patients undergoing RALRP is old aged and often present with comorbidities. Advanced age, underlying diabetes mellitus (DM) or hypertension renders the patient vulnerable to damage due to increased IOP. Moreover, the possibility of the patient having undiagnosed glaucoma is also increased, and therefore methods to prevent such complications are needed. As of now, intravenous hypnotic agents, inhalation anesthetics and opioids have been reported to decrease IOP by relaxing extraocular muscle tone and increasing aqueous humour outflow to some extent. Among these agents, propofol has been reported to be more effective than other inhalational anesthetics in decreasing IOP. The goal of this prospective, randomized controlled trial is to compare the effect of propofol and sevoflurane on IOP in patients undergoing RALRP in the steep Trendelenburg position with carbon dioxide pneumoperitoneum.

Inclusion Criteria:

1. ASA class 1 or 2
2. Adults over the age of 20 and under 70
3. Patients undergoing robot-assisted laparoscopic radical prostatectomy
4. Patients that have given informed consent

Exclusion Criteria:

1. Patients with known ophthalmic diseases (glaucoma, diabetic retinopathy, cataract, retinal detachment)
2. Patients with history of ophthalmic surgery
3. Patients with high baseline intraocular pressure (over 30 mmHg)
4. Patients with active cardiac conditions (unstable angina, congestive heart failure)
5. Patients with uncontrolled hypertension (diastolic blood pressure > 110 mmHg)
6. Patients with history of allergic reactions to propofol
7. Illiterate patients