Inclusion Criteria:  18 years of age or older Scheduled for a surgery where routine ureter identification is used Have signed an approved informed consent form for the study Be willing and able to comply with the study protocol  Exclusion Criteria:  Known allergy or history of adverse reaction to methylene blue Taking an antidepressant including, but not limited, to selective and non-selective serotonin reuptake inhibitors, or a psychiatric medication Glucose-6-phosphate dehydrogenase (G6PD) deficiency Renal dysfunction defined as estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2 Has participated in another investigational study within 30 days prior to surgery Pregnant or lactating subjects Subjects who, in the Investigator's and/or designee's opinion, have any medical condition that makes the subject a poor candidate for the investigational procedure, or interferes with the interpretation of study results