Assessment of postviral qualitative olfactory dysfunction using the short SSParoT in patients with and without parosmia.

PURPOSE: To examine if the short formed Sniffin Sticks Parosmia Test (SSParoT), a test for parosmia can distinguish cases with parosmia from cases without parosmia. METHODS: In this study, 63 patients with postviral olfactory dysfunction were investigated including both COVID and non-COVID cases. The age, symptom duration, degree of parosmia/phantosmia was collected. For olfactory function, the Sniffin Sticks olfactory score was obtained including scores for odor threshold, discrimination and identification. For assessment of parosmic changes, the short SSParoT was adopted and both hedonic range (HedRang) and direction (HedDir) was calculated. RESULTS: The mean HedRang of patients with parosmia (2.35, standard deviation, SD = 1.40) and without parosmia (2.78, SD = 1.09) was smaller than that in controls (4.5, SD = 2.15). However, the mean HedDir of both parosmia (- 0.32, SD = 0.98) and non-parosmia patients (0.04, SD = 1.07) was similar to controls (- 0.1, SD = 1.55). When considering that the 10th percentile of the distribution of SSParoT score should distinguish between patients with and without parosmia, the sensitivity of the HedRang was 29% and specificity was 67%. For HedDir, the sensitivity was 6% and specificity was 100%. Only the odor identification score (r = 0.34, p = 0.01) discriminated parosmia and non-parosmia while other measures including HedRang and HedDir did not. CONCLUSION: The present study showed that the short SSParoT score could not distinguish patients with parosmia from patients without parosmia. Although the SSParoT represents an innovative approach to assess parosmia, and could be useful in the tracking of parosmic changes, the development of measures to diagnose parosmia in an objective way remains a challenge.

Insight into the mechanisms of olfactory dysfunction by COVID-19.

One of the unique symptoms of COVID-19 is chemosensory dysfunction. Almost three years since the beginning of the pandemic of COVID-19, there have been many studies on the symptoms, progress, and possible causes, and also studies on methods that may facilitate recovery of the senses. Studies have shown that some people recover their senses even within a couple of weeks whereas there are other patients that fail to recover chemosensory functions fully for several months and some never fully recover. Here we summarize the symptoms and the progress, and then review the papers on the causation as well as the treatments that may help facilitate the recovery of the symptoms. Depending on the differences in the levels of severity and the locations where the main pathological venues are, what is most effective in facilitating recovery can vary largely across patients and thus may require individualized strategies for each patient. The goal of this paper is to provide some thoughts on these choices depending on the differences in the causes and severity.