A system for controlling a pressure inside a bladder through an endoscope, where the distal end portion of the endoscope is located inside the bladder and the endoscope has an inlet port through which fluid to enter the bladder and an outlet port through which fluid in the bladder to exit the bladder. The system includes one or more processors that receive a first signal from a first pressure sensor installed in a first fluid passageway that is in fluid communication with the inlet port； receives a second signal from a second pressure sensor installed in a second fluid passageway that is in fluid communication with the outlet port； and based on at least one of the first and second signals, actuates a valve installed in the first fluid passageway of fluid so as to adjust the flow rate into the bladder through the inlet port.
