Time-frequency analysis of gustatory event related potentials (gERP) in taste disorders.

In taste disorders, the key to a correct diagnosis and an adequate treatment is an objective assessment. Compared to psychophysical tests, EEG-derived gustatory event-related potentials (gERP) could be used as a less biased measure. However, the responses identified using conventional time-domain averaging show a low signal-to-noise ratio. This study included 44 patients with dysgeusia and 59 healthy participants, who underwent a comprehensive clinical examination of gustatory function. gERPs were recorded in response to stimulation with two concentrations of salty solutions, which were applied with a high precision gustometer. Group differences were examined using gERP analyzed in the canonical time domain and with Time-Frequency Analyses (TFA). Dysgeusic patients showed significantly lower scores for gustatory chemical and electrical stimuli. gERPs failed to show significant differences in amplitudes or latencies between groups. However, TFA showed that gustatory activations were characterized by a stronger power in controls than in patients in the low frequencies (0.1-4 Hz), and a higher desynchronization in the alpha-band (8-12 Hz). Hence, gERPs reflect the altered taste sensation in patients with dysgeusia. TFA appears to enhance the signal-to-noise ratio commonly present when using conventional time-domain averaging, and might be of assistance for the diagnosis of dysgeusia.

Treatment of tracheoesophageal fistulas following laryngectomy by customized prostheses-A bicentric case series.

Objective: Tracheoesophageal fistulas (TEF) following laryngectomy cause immense restrictions due to the inability of oral feeding, loss of voice rehabilitation, penetration of saliva, and permanent need of inflatable tracheal cannulas. Patients are consistently in threat of fatal aspiration pneumonias. The failure rate of surgical approaches to close the fistulas is high and an ultima ratio option by customized silicone prostheses can be considered. Methods: A retrospective analysis of 26 patients with a TEF was performed. Results: The fistulas occurred in average 40 months after laryngectomy caused by an enlargement of the voice fistula in 17 patients and problems in wound healing in 6 patients. The mean diameter of the fistula was 32 × 18 mm. Eight patients were treated by a button-shaped and 18 by a tube-shaped prosthesis. Complete oral feeding was possible in 8 and additional feeding by percutaneous endoscopic gastrostomy tube in 16 patients. Voice rehabilitation by voice prostheses was possible in 18 cases. Fifteen patients died in the course of the treatment either due to oncological progression or other reasons. The median follow-up time of the patients alive was 36 months (max 88 months) with 2.2 protheses replacements in mean (max 11). Conclusion: The treatment of TEF by customized prostheses can be considered as an ultima ration option if other approaches had failed. At least, partial oral nutrition and voice rehabilitation as well as protection from aspiration can be achieved in the majority of the patients. Level of Evidence: 4-Case series.

Oral Somatosensory Sensitivity in Patients With Taste Disturbance.

OBJECTIVE: The significance of the human sense of taste is typically underestimated until it is altered or even lost. Hypogeusia, a diminished capacity to taste, has an adverse influence on a patient's quality of life. Similar to interactions between the oral senses and between olfaction and intranasal trigeminal sensitivity, taste disturbance may also affect the mechanosensitivity of the tongue. In this study, we investigated the lingual tactile sensitivity of patients with subjective taste disturbance and people with normogeusia. STUDY DESIGN: Prospective case-control study. METHODS: Forty-six patients with subjective taste disturbance (mean age 60 years) and 43 participants with normogeusia (mean age 55 years) were enrolled and underwent a stereognostic test of edge and point sensitivity based on 3D-printed letters sized from 2 to 8 mm. Gustatory function and salivary production were also tested. RESULTS: Patients with dysgeusia needed significantly bigger letters to recognize them compared with controls (P = .01). Apart from this, patients with dysgeusia had no significant association between gustatory function and salivary production. Duration of dysgeusia and age were not associated with the presently obtained measures of gustatory or oral mechanosensory function. CONCLUSIONS: The results of this study indicate that taste dysfunction has a negative impact on oral mechanosensitivity and hence possibly on oral texture perception. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:2572-2577, 2021.

Follow-up of a national web-based survey on the SARS-CoV-2 infectious state of otorhinolaryngologists in Germany.

PURPOSE: The SARS-CoV­2 pandemic has affected the health and practice of otorhinolaryngologists (ORLs) for over 1 year. Follow-up data of a national survey with German ORLs were evaluated regarding differences between the two waves of the pandemic. METHODS: As in the initial survey, German ORLs were addressed via e­mail through the German Society of ORL, Head and Neck Surgery and the German ENT Association. All ORLs afflicted with SARS-CoV­2 were invited to participate in a web-based survey. General data on infections and concomitant parameters were evaluated. RESULTS: Since the start of the pandemic, 129 ORLs reported testing positive for SARS-CoV­2 in Germany. The ORLs infected during the first wave had a relative risk (RR) of 4.07 (95% CI: 3.20; 5.19) of contracting SARS-CoV­2. During the second wave, the RR decreased to 0.35 (95% CI: 0.28; 0.45). The availability of personal protective equipment (PPE) increased from the first to the second wave along with an increased perception of protection in the professional environment. The source of infection shifted from infections via medical staff during the first wave to patients and household exposure during the second wave. Regular medical practice was resumed by clinicians and general practitioners in the second wave. Nevertheless, a proportionally lower infection rate was observed compared with the German population as a whole. CONCLUSION: The data reflect a unique long-term survey of ORLs during the pandemic. Differences in the source of infection were seen between the first and second wave, confirming the need for appropriate PPE for medical professionals working in high-risk environments. Further strategies to reduce the risk of infection include consistent testing for SARS-CoV­2 in healthcare professionals, patients, and the general public as well as vaccination of high-risk medical groups.

Response to Glucocorticosteroids Predicts Olfactory Outcome After ESS in Chronic Rhinosinusitis.

OBJECTIVES: Olfaction is frequently impaired in chronic rhinosinusitis with nasal polyps (CRSwNP) and often improves after endoscopic sinus surgery (ESS). Data about dynamics of olfactory changes after ESS are lacking, and little information is available concerning whether preoperatively administered glucocorticosteroids predict postoperative olfaction. Therefore, the aim of this study was to examine dynamics of olfaction after ESS in relation to the effect of preoperative administration of glucocorticosteroids in CRSwNP. METHODS: This prospective study included 52 CRSwNP patients (30 men, 22 women, mean age 54 ± 14 years) divided into a control group (n = 31) subjected to ESS without preoperative steroids and a treatment group (n = 21) receiving orally administered glucocorticosteroids preoperatively. Self-ratings of olfaction and olfactory testing using the extended Sniffin' Sticks test battery (threshold, discrimination and identification [TDI] score) were performed. Olfaction was measured preoperatively; after termination of glucocorticosteroid treatment (only treatment group); and 2 weeks, 1 month, and 3 months postoperatively. RESULTS: After glucocorticosteroids, TDI score significantly improved in 57% of patients, and olfactory function remained unchanged in 43%. In addition, improvement in TDI score after steroids and 3 months postoperatively were significantly correlated (r = 0.66, P = 0.01). Patients whose olfaction did not improve after glucocorticosteroids did not benefit from surgery. Regarding postoperative olfactory dynamics, TDI score reached its maximum 1 month postoperatively and decreased again approximately 3 months after surgery. CONCLUSION: Glucocorticosteroids improved olfaction in CRSwNP comparable to surgery. In addition, changes in relation to steroids predicted olfactory outcome postoperatively. Regarding the olfactory dynamics, it could be demonstrated that olfactory function increased 1 month after surgery and decreased 3 months postoperatively. LEVEL OF EVIDENCE: 2 Laryngoscope, 130:1616-1621, 2020.

Olfactory bulb volume in patients with temporal lobe epilepsy.

The study aimed to investigate the volume of the olfactory bulb (OB) in patients with temporal lobe epilepsy (TLE). Specifically, we wanted to see whether the olfactory deficit typically found in TLE patients also exerts a top-down influence on the OB. Twenty patients, and 20 age- and sex-matched healthy controls underwent olfactory testing by means of the Sniffin' Sticks testing device (measurement of odor threshold, and identification abilities). In addition, they underwent an MR scan with 2-mm-thick T2-weighted fast spin-echo images without interslice gap in the coronal plane covering the anterior and middle segments of the base of the skull. Olfactory function was significantly impaired in TLE patients compared to healthy controls both at threshold level and for odor identification (p < 0.001); in addition, OB volumes were smaller than in controls (p = 0.013). The deficit seen at the level of the OB did not correlate with the side of the epileptic focus. Assuming that the olfactory deficit in TLE patients is due to the central nervous epileptic focus it appears that the OB volume is not only subject to changes in the periphery of the olfactory system, but also changes as a consequence to changes at a cortical level.