Olfaction is one of the five basic human senses, and it is known to be one of the most primitive senses. The sense of olfaction may have been critical for human survival in prehistoric society, and although many believe its importance has diminished over time, it continues to have an impact on human interaction, bonding, and propagation of the species. Even if we are unaware of it, the sense of smell greatly affects our lives and is closely related to overall quality of life and health. Nonetheless, olfaction has been neglected from a scientific perspective compared to other senses. However, olfaction has recently received substantial attention since the loss of smell and taste has been noted as a key symptom of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Studies investigating olfaction loss in association with coronavirus disease 2019 (COVID-19) have revealed that olfactory dysfunction can be both conductive and sensorineural, possibly causing structural changes in the brain. Olfactory training is an effective treatment for olfactory dysfunction, suggesting the reorganization of neural associations. A reduced ability to smell may also alert suspicion for neurodegenerative or psychiatric disorders. Here, we summarize the basic knowledge that we, as otorhinolaryngologists, should have about the sense of smell and the peripheral and central olfactory pathways for managing and helping patients with olfactory dysfunction.
Objectives: Laryngeal ultrasonography (LUS) has been suggested as an alternative diagnostic tool for unilateral vocal fold paralysis (UVFP). The present study applied LUS and quantitative laryngeal electromyography (LEMG) in female UVFP patients to investigate the pathophysiologic mechanisms of UVFP.
Methods: In this cross-sectional study, vocal fold (VF) length parameters included resting and phonating VF length measured using B-mode LUS, and color Doppler vibrating length (CDVL) measured using the color Doppler mode.
Results: Forty female patients with UVFP were enrolled, among whom 11 and 29 were assigned to the thyroarytenoid (TA) muscle+cricothyroid (CT) muscle group (with CT involvement) and the TA (without CT involvement) group, respectively. In the TA group, the turn frequency in thyroarytenoid-lateral cricoarytenoid (TA-LCA) on the paralyzed side, as observed through LEMG, correlated with the VF length during the resting phase (R=0.368, P=0.050) and CDVL values (R=0.627, P=0.000) on the paralyzed side. In the TA+CT group, the turn ratio in the CT muscle correlated with the normalized phonatory vocal length change (nPLC; R=0.621, P=0.041) on the paralyzed side.
Conclusion: CDVL and nPLC are two parameters that can be utilized to predict the turn frequencies of TA-LCA in UVFP cases without CT involvement, and the turn ratio of CT in cases of UVFP with CT involvement, respectively. The findings suggest that LUS, as a noninvasive tool, can serve as an alternative method for assessing the severity of laryngeal nerve injury and offer valuable insights into the pathophysiology of UVFP.
Objectives: Several criteria exist for classifying chronic rhinosinusitis with nasal polyps (CRSwNP) as eosinophilic or non-eosinophilic. This study attempted to evaluate several criteria for defining eosinophilic CRSwNP from clinical and immunological perspectives.
Methods: A cohort of 84 patients (73 patients with CRSwNP and 11 control patients) was retrospectively analyzed. Patients were divided into eosinophilic and non-eosinophilic CRSwNP based on four different criteria: eosinophils (EOS) accounting for more than 20% of the total inflammatory cells; ≥70 EOS per high-power field (HPF); >55 EOS/HPF; and ≥10 EOS/HPF. Preoperative clinical characteristics, the immunological profiles of 14 cytokines from nasal tissue, and postoperative outcomes were compared between eosinophilic and non-eosinophilic CRSwNP based on each criterion. These criteria were immunologically validated by using 14 cytokines to predict the performance of tissue eosinophilia with a random forest model.
Results: Patients with eosinophilic CRSwNP were significantly older when the criterion of ≥10 EOS/HPF or EOS >20% was used. The number of patients with aspirin intolerance was significantly higher in eosinophilic CRSwNP based on the criterion of EOS >20%. From an immunological perspective, non-type 2 inflammatory cytokines were significantly higher in non-eosinophilic CRSwNP with the criterion of EOS >20% of the total inflammatory cells. In addition, the criterion of EOS >20% of the total inflammatory cells resulted in the best prediction of eosinophilic CRSwNP, with an accuracy of 88.10% and area under the curve of 0.94.
Conclusion: Clinical and immunological characteristics were different between eosinophilic and non-eosinophilic CRSwNP depending on a variety of criteria, and the.
Results: of this study should be taken into account when choosing the criterion for defining eosinophilic CRSwNP and interpreting the data accordingly.