The present invention generally relates to, amongst other things, systems, devices, materials, and methods that can improve the accuracy and/or precision of nitric oxide therapy by, for example, reducing the dilution of inhaled nitric oxide (NO). As described herein, NO dilution can occur because of various factors. To reduce the dilution of an intended NO dose, various exemplary nasal cannulas, pneumatic configurations, methods of manufacturing, and methods of use, etc. are disclosed.