The present system is directed in various embodiments to devices, systems and methods for detection, evaluation and/or monitoring olfactory dysfunction by measuring and determining the patient's olfactory detection threshold for the left and the right nostril. More specifically, the present invention relates to devices, systems and methods for detecting an asymmetric differential in a patient's olfactory detection threshold (left vs right nostril) which, when present, may be used as a device to detect, diagnose and/or monitor olfactory deterioration resulting from certain neurodegenerative disorders such as Alzheimer's disease.
