is the official Journal of the European and International Rhinologic Societies and appears quarterly in March, June, September and December. Cited in Pubmed, Current Contents, Index Medicus, Exerpta Medica and Embase Founded in 1963 by H.A.E. van Dishoeck, Rhinology is a worldwide non-profit making journal. The journal publishes original papers on basic research as well as clinical studies in the major field of rhinology, including physiology, diagnostics, pathology, immunology, medical therapy and surgery of both the nose and paranasal sinuses. Review articles and short communications are also pulished. All papers are peer-reviewed. Letters-to-the-editor provide a forum for comments on published papers, and are not subject to editorial revision except for correction of English language.In-depth studies that are too long to be included into a regular issue can be published as a supplement. Supple ments are not subject to peer-review.

Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation and initial results of a multi-lingual, international questionnaire to assess self-reported quantity and quality of perception in three distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, 8 other, ages 19-79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change ±100) revealed a mean reduction of smell (-79.7 ± 28.7, mean ± SD), taste (-69.0 ± 32.6), and chemesthetic (-37.3 ± 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell, but also affects taste and chemesthesis. The multimodal impact of COVID-19 and lack of perceived nasal obstruction suggest that SARS-CoV-2 infection may disrupt sensory-neural mechanisms.

Background and purpose There is limited literature consisting of case reports or series on olfactory bulb imaging in COVID-19 olfactory dysfunction. An imaging study with objective clinical correlation is needed in COVID-19 anosmia in order to better understand underlying pathogenesis. Material and methods We evaluated 23 patients with persistent COVID-19 olfactory dysfunction. Patients included in this study had a minimum 1-month duration between onset of olfactory dysfunction and evaluation. Olfactory functions were evaluated with Sniffin’ Sticks Test. Paranasal sinus CTs and MRI dedicated to olfactory nerves were acquired. On MRI, quantitative measurements of olfactory bulb volumes and olfactory sulcus depth and qualitative assessment of olfactory bulb morphology, signal intensity and olfactory nerve filia architecture were performed. Results All patients were anosmic at the time of imaging based on olfactory test results. On CT, Olfactory cleft opacification was seen in 73.9% of cases with a mid and posterior segment dominance. 43.5% of cases had below normal olfactory bulb volumes and 60.9% of cases had shallow olfactory sulci. 54.2% of cases had changes in normal inverted J shape of the bulb. 91.3% of cases had abnormality in olfactory bulb signal intensity in the forms of diffusely increased signal intensity, scattered hyperintense foci or microhemorrhages. Evident clumping of olfactory filia was seen in 34.8% of cases and thinning with scarcity of filia in 17.4%. Primary olfactory cortical signal abnormality was seen in 21.7% of cases. Conclusion Our findings indicate olfactory cleft and olfactory bulb abnormalities are seen in COVID-19 anosmia. There was a relatively high percentage of olfactory bulb degeneration. Further longitudinal imaging studies could shed light on the mechanism of olfactory neuronal pathway injury in COVID-19 anosmia.

2b. Laryngoscope, 125:1763-1766, 2015.

In a preregistered, cross-sectional study we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC=0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.

Objective/Hypothesis With the COVID‐19 pandemic, chemosensory dysfunction are among the most prevalent symptoms. Most reports are subjective evaluations, which have been suggested to be unreliable. The objective is to test chemosensory dysfunction and recovery based on extensive psychophysical tests in COVID‐19 during the course of the disease. Study Design Prospective cohort study. Methods A total of 111 patients from four centers participated in the study. All tested positive for SARS‐COV‐2 with RT‐PCR. They were tested within 3 days of diagnosis and 28 to 169 days after infection. Testing included extensive olfactory testing with the Sniffin' Sticks test for threshold, discrimination and identification abilities, and with the Taste Sprays and Taste Strips for gustatory function for quasi‐threshold and taste identification abilities. Results There was a significant difference in olfactory function during and after infection. During infection 21% were anosmic, 49% hyposmic, and 30% normosmic. After infection only 1% were anosmic, 26% hyposmic, and 73% normosmic. For gustatory function, there was a difference for all taste qualities, but significantly in sour, bitter, and total score. Twenty‐six percent had gustatory dysfunction during infection and 6.5% had gustatory dysfunction after infection. Combining all tests 22% had combined olfactory and gustatory dysfunction during infection. After infection no patients had combined dysfunction. Conclusions Chemosensory dysfunction is very common in COVID‐19, either as isolated smell or taste dysfunction or a combined dysfunction. Most people regain their chemosensory function within the first 28 days, but a quarter of the patients show persisting dysfunction, which should be referred to specialist smell and taste clinics for rehabilitation of chemosensory function. Level of Evidence 3 Laryngoscope, 131:1095–1100, 2021

The U-Sniff is a valid and reliable method of testing olfaction in children and can be used internationally.

Objective This study aimed to investigate the differences in olfactory cleft (OC) morphology in coronavirus disease 2019 (COVID-19) anosmia compared to control subjects and postviral anosmia related to infection other than severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Study Design Prospective. Setting This study comprises 91 cases, including 24 cases with anosmia due to SARS-CoV-2, 38 patients with olfactory dysfunction (OD) due to viral infection other than SARS-CoV-2, and a control group of 29 normosmic cases. Methods All cases had paranasal sinus computed tomography (CT), and cases with OD had magnetic resonance imaging (MRI) dedicated to the olfactory nerve. The OC width and volumes were measured on CT, and T2-weighted signal intensity (SI), olfactory bulb volumes, and olfactory sulcus depths were assessed on MRI. Results This study showed 3 major findings: the right and left OC widths were significantly wider in anosmic patients due to SARS-CoV-2 (group 1) or OD due to non–SARS-CoV-2 viral infection (group 2) when compared to healthy controls. OC volumes were significantly higher in group 1 or 2 than in healthy controls, and T2 SI of OC area was higher in groups 1 and 2 than in healthy controls. There was no significant difference in olfactory bulb volumes and olfactory sulcus depths on MRI among groups 1 and 2. Conclusion In this study, patients with COVID-19 anosmia had higher OC widths and volumes compared to control subjects. In addition, there was higher T2 SI of the olfactory bulb in COVID-19 anosmia compared to control subjects, suggesting underlying inflammatory changes. There was a significant negative correlation between these morphological findings and threshold discrimination identification scores. Level of Evidence Level 4.