The cause of the olfactory problems in sinonasal diseases is in many cases nasal obstruction. Chronic inflammation in the nose and sinuses is the most common chronic medical condition in the United States of America and more than half of the affected individuals have olfactory symptoms. Sinonasal diseases like nasal polyps or chronic inflammation of the nasal passages and/or paranasal sinuses (rhinitis, sinusitis, rhinosinusitis) are the most common cause of olfactory dysfunction (Figure 1) ]. The three most common causes are sinonasal disease, upper respiratory infection, and head trauma (Figure 1). There are many causes of olfactory dysfunction ]. Distorted perception is more common when the smell loss is less severe. Of those who suffer from smell loss, between 10 and 60% also have distorted olfactory perceptions. Olfactory dysfunction, like visual and auditory impairment, becomes more prevalent with increasing age. Men are more likely to suffer from it than women and smoking, working in a factory environment, low level of education, and having a low household income have been reported as risk factors. Olfactory dysfunction is a very common condition with a reported prevalence between 4 and 25%. Phantosmia and parosmia often co-occur and parosmia is more common than phantosmia. Distorted olfactory perception can be subdivided into parosmia (distorted olfactory experiences in the presence of an odor) and phantosmia (distorted olfactory experience in the absence of an odor) ]. Patients with partial smell loss often also suffer from distorted olfactory perception. Smell loss can be partial, a condition called hyposmia, or total, a condition called anosmia. Olfactory perceptual changes can be quantitative (smell loss) or qualitative (smell distortions). Two recent patient memoires describe vividly the often unanticipated consequences of changes to one’s sense of smell from the patient’s perspective.

Christmas Cracker by R.L. Cherry