MEDICAL TREATMENT SYSTEM AND METHODS USING A PLURALITY OF FLUID LINES

A medical treatment system, such as peritoneal dialysis system, may include control and other features to enhance patient comfort and ease of use. For example, a peritoneal dialysis system may include patient line state detector for detecting whether a patient line is primed before it is to be connected to the patient. The patient line state detector can also the ability to detect whether a patient line has been properly mounted for priming. Both patient line presence/absence and fill state can be determined using an optical system, e.g., one that employs a single optical sensor.