depression, anxiety, and sleep disturbances. Individuals with ENS may not experience all of these symptoms. A study with a very small number of ENS patients (22) found that ENS was associated with hyperventilation syndrome (HPV) in 77.3% of the study population. The study suggests, but does not prove, that there could be an epidemiological link between ENS and HPV. The authors hypothesize that the link between ENS and HPV could be explained by the nasal injury that occurs to the turbinates that alters the respiratory control system. Cause The cause of ENS is due to the body not accepting the new airflow in the nasal passages following surgical procedures. The nose is an incredibly complex area of the body and one that has been very poorly researched in terms of the effects on aerodynamics from surgical procedures. In many patients with ENS, the airflow is modeled as being more turbulent with less laminar flow across the mucosa. This change in airflow leads to an imbalance of / levels in the body, which will show hyperventilation-like symptoms in patients. This reduced amount of mucus in the nose can also be attributed to the change in airflow often resulting in dry cool air hitting the back of the patients throat. x One possible cause may be changes to the nasal mucous membrane and to the nerve endings in the mucosa resulting from chronic changes to the temperature and humidity of the air flowing inside the nose, caused in turn by removal or reduction of the turbinates. Direct damage to the nerves may be a result of surgical intervention; however, as of 2015, there is no technology that allows the mapping of the sensory nerves within the nose, so it is difficult to determine whether this is causative of ENS. Investigators have been unable to identify consistent diagnostic or precipitating features, psychological causes leading to a psychosomatic condition have been proposed. There seems to be a relation between reduced levels of nasal nitric oxide and depression/anxiety symptoms in ENS patients. Both have been shown to be reversible via implantation surgery. It has been proposed, that the airflow in ENS patients is changed so that most of the air flows through the middle meatus, compared to most of the air flowing through the inferior meatus in healthy individuals. This can be corrected via inferior meatus augmentation (IMAP surgery). Diagnosis No consensus criteria exist for