The effect of nasopharyngeal obstruction on the olfactory bulb volume and olfactory sulcus depth in children : First author.

PURPOSE: Smell ability is associated with nasopharyngeal obstruction. Herein, we evaluated the effect of nasopharyngeal obstruction by adenoid hypertrophy on the olfactory bulb (OB) volume and olfactory sulcus (OS) depth in children. METHODS: A total of 135 children who were candidates for brain magnetic resonance imagining scanning were enrolled in the study. The olfactory disorder-negative statements questionnaire was utilized to assess the patient-reported olfactory status. A validated sleep questionnaire was used to assess sleeping status. According to the adenoidal/nasopharyngeal (A/N) ratio, the children were divided into two groups: those with an A/N ratio ≤ 0.5 (n = 70) and those with an A/N ratio > 0.5 (n = 65). OB volume and OS depth measurements were performed on coronal T2-weighted images using planimetric manual contouring. The mean OB volumes and OS depths on the right and left sides were used for the evaluation. RESULTS: The mean OB volume of the group with an A/N ratio > 0.5 was significantly lower than that of the group with an A/N ratio ≤ 0.5 (P = 0.003), while there was no difference in the mean OS depth between groups (P = 0.061). In those with an A/N ratio > 0.5, the mean OB volume in older children (aged 9-12 years) was significantly lower than that in younger children (aged 5-8 years) (P = 0.012). In terms of laterality, the OS depth on the right side was significantly larger than that on the left side in both groups (P = 0.039 and P = 0.001). In the group with an A/N ratio ≤ 0.5, the OB volume on the right side was also significantly larger than that on the left side (P = 0.040); however, no such difference was observed in the group with an A/N ratio > 0.5 (P = 0.630). No sex-based differences were evident for any variable. CONCLUSIONS: Children with nasopharyngeal obstruction greater than 50% have a significantly smaller OB volume. Our results suggest that morphological alterations in OB may contribute to the pathogenic mechanism of olfactory dysfunction related to nasopharyngeal obstruction.

Clinical significance of the cognition-related pathogenic proteins in plasma neuronal-derived exosomes among normal cognitive adults over 45 years old with olfactory dysfunction.

OBJECTIVES: Exosomal Phospho-Tau-181(P-T181-tau), Total tau (T-tau), and amyloid-ß peptide 42 (Aß42) have been proved the capacity for the amnestic mild cognitive impairment (MCI) and the diagnosis of Alzheimer's disease (AD). This study aimed to explore the cognitive function and the levels of P-T181-tau, T-tau, and Aß42 in neuronal-derived exosomes (NDEs) extracted from plasma in normal cognitive adults over 45 years old with olfactory dysfunction. METHODS: A cross-sectional survey of 29 participants aged over 45 was conducted. Plasma exosomes were isolated, precipitated, and enriched by immuno-absorption with anti- L1 cell adhesion molecule (L1CAM) antibody. NDEs were characterized by CD81, and extracted NDE protein (P-T181-tau, T-tau, and Aß42) biomarkers were quantified by enzyme-linked immunosorbent assay (ELISAs). Olfactory performance was assessed by Sniffin' Sticks and cognitive performance was assessed by Montreal Cognitive Assessment (MoCA). RESULTS: There was no significant difference between adults with olfactory dysfunction and without olfactory dysfunction regarding the cognitive function as measured by MoCA and all the participants showed normal cognition. Adults with olfactory dysfunction showed a higher concentration of P-T181-tau in plasma NDEs than did adults without olfactory dysfunction (P = 0.034). Both the levels of P-T181-tau (r = - 0.553, P = 0.003) and T-tau (r = - 0.417, P = 0.034) negatively correlated with the odor identification scores. In addition, the level of T-tau negatively correlated with MoCA scores (r = - 0.597, P = 0.002). The levels of P-T181-tau (r = - 0.464, P = 0.022) and T-tau (r = - 0.438, P = 0.032) negatively correlated with the delayed recall scores. CONCLUSIONS: This study demonstrated that cognition-related pathogenic proteins including P-T181-tau in plasma NDEs were significantly increased in adults over 45 years old with olfactory dysfunction before the occurrence of cognitive impairment. The impaired odor identification and the delayed recall function were highly associated with the increased levels of P-T181-tau and T-tau in plasma NDEs.

Prognostic value of olfactory evoked potentials in patients with post-infectious olfactory dysfunction.

PURPOSE: Prognostic assessment of patients with post-infectious olfactory dysfunction (PIOD) poses a challenge for clinicians. While there have been some studies on the prognostic factors of PIOD focusing on demographic factors, the aim of this study was to investigate whether event-related potentials (ERPs) could be used as a new predictor of olfactory recovery in PIOD. METHODS: This was a retrospective study involving patients who underwent olfactory examinations using Sniffin' Sticks test before treatment and after 1 year of follow-up. The responder group was defined by an increase of threshold-discrimination-identification (TDI) score of ≥ 6 points. All patients underwent ERP examination and the amplitude and latency of each wave of ERPs were recorded before treatment. RESULTS: A total of 61 patients (age 47.50 ± 11.04 years, 27 males) were analyzed. The presence of olfactory ERPs (oERPs) was greater in the responder group than in the non-responder group (P = 0.007), while that of trigeminal ERPs (tERPs) did not differ between the two groups (P = 0.346). Logistic-regression analyses showed that factors associated with improvement of subjective olfactory function were duration (OR, 1.604; 95% CI, 1.062-2.423; P = 0.025), initial threshold (odds ratio [OR], 0.043; 95% confidence interval [CI], 0.004-0.439; P = 0.008), and latency of N1 in oERPs (OR, 1.007; 95% CI, 1.001-1.013; P = 0.021). CONCLUSION: Our study shows that duration of OD, initial threshold, and latency of N1 in oERPs were associated with olfactory improvement in PIOD patients, which may provide guidance for clinicians.

The impact of obstructive apnea sleep syndrome on chemical function.

OBJECTIVE/HYPOTHESIS: To investigate the impact of obstructive sleep apnea syndrome (OSAS) on the olfactory and gustatory functions, and the potential mechanisms affecting olfactory and gustatory functions. MATERIALS AND METHODS: A total of 120 men between the ages of 41 and 70 (mean age (SD) = 56 ± 7.5) were divided into three groups according to polysomnography results: snoring group, mild to moderate OSAS group, and severe OSAS group. Olfactory and gustatory functions were evaluated by the Sniffin' Sticks test and the triple-drop method, respectively. Otorhinolaryngologic examination, as well as sleep and quality of life questionnaires, were completed by all subjects one day before or after polysomnography. RESULTS: There was a significant difference in odor thresholds (THR), odor discrimination (OD), odor identification (OI), thresholds-discrimination-identification (TDI) (p < 0.001, p < 0.001, p = 0.003, p < 0.001), and total taste score (p = 0.004, p = 0.021, p = 0.006) in all three groups. Of the subjects in the OSAS group, 43 (54%) exhibited olfactory dysfunction, including 18 subjects (45%) in the mild to moderate group and 25 subjects (63%) in the severe group. Significant negative correlations were found between all olfactory parameters and polysomnography parameters. Furthermore, a negative correlation was present between the total taste scores and the apnea-hypopnea index (AHI). CONCLUSION: Men with OSAS exhibited impairment in olfactory and gustatory functions. Significant correlations were found between AHI and olfactory parameters, as well as between AHI and total taste scores.

Adequate continuous positive airway pressure therapy reduces mortality in Chinese patients with obstructive sleep apnea.

BACKGROUND: Severe obstructive sleep apnea (OSA) is a risk factor for mortality. The ability of continuous positive airway pressure (CPAP) therapy to mitigate this increased risk of death has not been studied in Chinese adults. The objective of our study was to compare mortality in Chinese patients with simple snoring, untreated OSA, and OSA treated with CPAP. METHODS: We recruited adults with OSA or simple snoring from our sleep medicine clinic. OSA was diagnosed using standard polysomnography. Subjects were followed at least annually for a mean of 8.9 years (SD 1.9). CPAP compliance was checked with the built-in meter. We then assessed all-cause mortality. RESULTS: Five hundred fifty simple snorers, 257 with untreated mild OSA, 316 with untreated moderate OSA, 457 with untreated severe OSA, and 235 with mild to severe OSA treated with CPAP were included. Simple snorers had a much lower mortality rate (2.98 per 1000 person-years [95% CI, 2.93 to 3.02]) than the untreated severe OSA group (11.07 per 1000 person-years [95%CI, 10.86 to 11.29]; P < 0.0001). Compared with simple snorers, fully adjusted mortality was highest in the untreated, severe OSA group (hazard ratio [HR], 3.51 [95%CI, 1.93 to 6.39]). Treatment of severe OSA patients with CPAP eliminated this increase in mortality (HR, 0.81[95%CI, 0.36-1.86]). CONCLUSIONS: Severe OSA significantly markedly increases the risk of death in Chinese patients and CPAP treatment with adequate compliance reduces this risk.

Gray matter volume reduction of olfactory cortices in patients with idiopathic olfactory loss.

Idiopathic olfactory loss (IOL) is a common olfactory disorder. Little is known about the pathophysiology of this disease. Previous studies demonstrated decreased olfactory bulb (OB) volume in IOL patients when compared with controls. The aim of our study was to investigate structural brain alterations in areas beyond the OB. We acquired T1-weighted magnetic resonance images from 16 patients with IOL and from 16 age- and sex-matched controls on a 3T scanner. Voxel-based morphometry (VBM) was performed using VBM8 toolbox and SPM8 in a Matlab environment. Psychophysical testing confirmed that patients had higher scores for Toyota and Takagi olfactometer and lower scores for Sniffin' Sticks olfactory test than controls (t = 46.9, P < 0.001 and t = 21.4, P < 0.001, respectively), consistent with olfactory dysfunction. There was a significant negative correlation between the 2 olfactory tests (r = -0.6, P = 0.01). In a volume of interest analysis including primary and secondary olfactory areas, we found patients with IOL to exhibit gray matter volume loss in the orbitofrontal cortex, anterior cingulate cortex, insular cortex, parahippocampal cortex, and the piriform cortex. The present study indicates that changes in the central brain structures proximal to the OB occur in IOL. Further investigations of this phenomenon may be helpful to elucidate the etiology of IOL.

Gray matter alteration in isolated congenital anosmia patient: a voxel-based morphometry study.

Decreased volume of gray matter (GM) was observed in olfactory loss in patients with neurodegenerative disorder. However, GM volume has not yet been investigated in isolated congenital anosmia (ICA) people. We herewith investigated the volume change of gray matter of an ICA boy by morphometric analysis of magnetic resonance images (voxel-based morphometry), and compared with that of 20 age-matched healthy controls. ICA boy presented a significant decrease in GM volume in the orbitofrontal cortex, anterior cingulate cortex, middle cingulate cortex, thalamus, insular cortex, cerebellum, precuneus, gyrus rectus, subcallosal gyrus, middle temporal gyrus, fusiform gyrus and piriform cortex. No significant GM volume increase was detected in other brain areas. The pattern of GM atrophy was similar as previous literature reported. Our results identified similar GM volume alterations regardless of the causes of olfactory impairment. Decreased GM volume was not only shown in olfactory bulbs, olfactory tracts and olfactory sulcus, also in primary olfactory cortex and the secondary cerebral olfactory areas in ICA people. This is the first study to evaluate GM volume alterations in ICA people.

Disturbed microbiota-metabolites-immune interaction network is associated with olfactory dysfunction in patients with chronic rhinosinusitis.

Purpose: Olfactory dysfunction (OD) is a debilitating symptom frequently reported by patients with chronic rhinosinusitis (CRS) and it is associated with a dysregulated sinonasal inflammation. However, little information is available about the effect of the inflammation-related nasal microbiota and related metabolites on the olfactory function in these patients. Therefore, the current study aimed to investigate the nasal microbiota-metabolites-immune interactions and their role in the pathogenesis of OD in CRS patients. Methods: 23 and 19 CRS patients with and without OD, respectively, were enrolled in the present study. The "Sniffin' Sticks" was used to measure the olfactory function, while the metagenomic shotgun sequencing and the untargeted metabolite profiling were performed to assess the differences in terms of the nasal microbiome and metabolome between the two groups. The levels of nasal mucus inflammatory mediators were investigated by a multiplex flow Cytometric Bead Array (CBA). Results: A decreased diversity in the nasal microbiome from the OD group compared to the NOD group was evidenced. The metagenomic analysis revealed a significant enrichment of Acinetobacter johnsonii in the OD group, while Mycoplasma arginini, Aeromonas dhakensis, and Salmonella enterica were significantly less represented (LDA value > 3, p < 0.05). The nasal metabolome profiles were significantly different between the OD and NOD groups (P < 0.05). The purine metabolism was the most significantly enriched metabolic subpathway in OD patients compared with NOD patients (P < 0.001). The expressions of IL-5, IL-8, MIP-1α, MCP-1, and TNF were statistically and significantly increased in the OD group (P < 0.05). All these data, including the dysregulation of the nasal microbiota, differential metabolites, and elevated inflammatory mediators in OD patients demonstrated a clear interaction relationship. Conclusion: The disturbed nasal microbiota-metabolite-immune interaction networks may be implicated in the pathogenesis of OD in CRS patients and the underlying pathophysiological mechanisms need to be further investigated in future studies.

Analysis of effects of laryngopharyngeal reflux disease and proton pump inhibitor treatment on Eustachian tube function in patients with obstructive sleep apnea hypopnea.

OBJECTIVE: This study aims to explore the effects of laryngopharyngeal reflux disease (LPRD) and proton pump inhibitor (PPI) treatment on Eustachian tube function in patients with obstructive sleep apnea (OSA). METHODS: The Eustachian tube score-7 (ETS-7) was observed before and after PPI treatment in the control group, OSA only group, and OSA + LPRD group. RESULTS: Age, sex, smoking history, and drinking history showed no differences among 3 groups (P > .05). The body mass index (BMI) in the control group was lower than that in other groups (P < .017). Before PPI treatment, the abnormality rate of ETS-7 in the OSA + LPRD group statistically differed from that in the control group and the OSA only group (P < .017). After PPI treatment, the abnormality rate of ETS-7 in the OSA + LPRD group exhibited no significant differences compared with that in the control group and the OSA only group (P > .017), and it declined remarkably compared with that before PPI treatment (75% vs 35%, χ2 = 13.334, P = .001). Moreover, the multivariate analysis revealed that only LPRD had an independent correlation with the abnormality of ETS-7 (OR = 1.245, 95% CI: 1.759-6.861, P = .000). CONCLUSION: In view of its high incidence in OSA patients, LPRD may be a considerable factor for the high incidence of abnormality rate of ETS-7 in OSA patients, and PPI therapy is of significant value in improving Eustachian tube function in OSA patients with LPRD.

[Analysis of clinical characteristics in the patient with olfactory disorders].

Objective:To analyze the etiology and clinical features of patients with olfactory disorders （OD） , and to explore the importance of gustatory testing in patients with OD. Methods:Clinical data of 335 consecutive patients with OD who seek medical consultation in the smell and taste center from the year 2015 to 2021 was retrospectively analyzed. The clinical characteristics of patients with OD were analyzed thorough a structured interview of medical history, otolaryngologic examinations, olfactory tests（Sniffin' Sticks test） and gustatory function test（whole-mouth taste test）. SPSS 17.0 software was used to analyze the clinical characteristics of patients with OD and related factors which have effect on gustatory function. Results:Among the patients， 36.4% of them caused by head trauma, 22.1% for upper respiratory tract infection（URTI）, 15.5% for rhinosinusitis diseases（RSD）, 11.9% for idiopathic, 9.6% for congenital anosmia, and 4.5% for other causes, respectively. The features were different in patients with different kinds of OD: most patients with head trauma were anosmic（χ²=27.958, P<0.001）, and no difference was found in gender and age（P>0.05 for both）; most patients with URTI were anosmic（χ²=21.568, P<0.001）, and female patients were more than male（χ²=5.898, P<0.05）, elder patients were more than younger（χ²=12.963, P<0.001）; most patients with RSD were anosmic（χ²=12.106, P<0.05）, and male patients were more than female（χ²=4.655, P<0.05）; elder patients were more than younger for idiopathic OD（χ²=5.284, P<0.05）, but no sex difference was found（P>0.05）; patients with congenital anosmia were all lost their smell since they were born, and no sex difference was found in the disease（P>0.05）. Fifty-seven of 146（39%） patients whose gustation was assessed had gustatory dysfunction. Gustatory function was significantly associated with the causes of OD（r=0.368, P<0.05）, but not related to olfactory function, age and sex（P>0.05 for all）. Conclusion:The leading causes of olfactory dysfunction were head trauma, URTI, RSD, and idiopathic causes. Each of OD had its own distinct clinical features. Gustatory dysfunction were common in patients with OD, and gustatory function was related to the causes of OD. High priority should be given to gustatory function evaluation for the patients with OD.

[Prognostic value of olfactory bulb volume in patients with post-viral olfactory dysfunction].

Objective:The purpose of this study was to compare the olfactory function examination results of patients with post-viral olfactory dysfunction（PVOD） in different prognostic groups and analyze prognostic factors, especially the influence of olfactory bulb volume（OBV） on prognosis, so as to provide objective basis for clinical diagnosis and treatment. Methods:After approval by the hospital ethics committee, the patients with PVOD admitted to Beijing Anzhen Hospital's outpatient department from January 2019 to December 2019 were followed up for at least 1 year. These patients completed the Sniffin' Sticks test and MRI examination of the olfactory pathway before treatment. According to the results of the Sniffin' Sticks test after 1 year follow-up（threshold-discrimination-identification（TDI） score of the patients was increased at least 6 points）, the patients were divided into two groups as the improvement group and the non-improvement group. The prognostic factors of PVOD patients were preliminarily determined by comparing the differences of various factors and the results of olfactory function examination between the two groups. Results:In this study, 47 patients with PVOD were included, with the smell improvement rate was 53.2%. Compared with the improvement group, the patients in the non-improvement group had longer duration, poorer initial olfactory function, higher olfactory threshold, and poorer olfactory discrimination and recognition ability（All P<0.01）. There was no statistical difference in terms of gender, age, allergic rhinitis and smoking between the two groups（All P>0.05）.The OBV of the non-improvement group was （59.48±23.92） mm³, which was significantly lower than that in the improvement group（[92.77±14.35]mm³, P<0.001）. Multiple logistic regression analysis showed that prognostic factors included course of disease（OR 0.677, 95%CI 0.461-0.993, P=0.046）, initial T value（OR 263.806, 95%CI 1.028-67 675.884, P=0.049） and OBV（OR 1.160, 95%CI 1.002-1.343, P=0.047）. The area under the receiver operating characteristic curve（ROC curve） of OBV was 0.888（0.797-0.979, P<0.001）. The correct diagnostic index of OBV≥78.50 mm³was used to determine the prognosis of olfactory function, with a specificity of 0.818 and a sensitivity of 0.840. The ROC curve analysis showed that the area under the ROC curve of duration was 0.822（0.703-0.940, P<0.001）. The correct diagnostic index of the duration ≤6 months was used to determine the prognosis of olfactory function, with a specificity of 0.727 and a sensitivity of 0.800. The area of T score was 0.793（0.662-0.924, P=0.001）. T score ≥1.25 was used as the correct diagnostic index to determine the prognosis of olfactory function. The specificity and sensitivity were 0.818 and 0.680, respectively. Conclusion:The prognosis of olfactory function in PVOD patients is related to the course of disease, the degree of olfactory loss and OBV. Those with no improvement in olfactory function have a longer disease course, aggravated olfactory damage and reduced OBV than those with improved olfactory function. The factors of Duration ≤6 months, T value ≥1.25 and OBV≥78.50 mm³suggested better prognosis, and the results of objective olfactory examination have greater value in evaluating the prognosis of olfactory function.

Olfactory impairment and the risk of cognitive decline and dementia in older adults: a meta-analysis.

INTRODUCTION: The prediction of the impact of olfactory impairment on cognitive decline in older adults has been different among different age groups. OBJECTIVE: This meta-analysis sought to estimate the predictive power of olfactory impairment on cognitive decline during follow-up in older adults of different ages. MATERIAL AND METHODS: A medical literature search was carried out using these databases for eligible studies: MEDLINE, COCHRANE and EMBASE. Studies recording olfaction and cognition detection at the beginning and end of the follow-up were included in the preliminary screening. The medical records of older adults without cognitive impairment at the beginning of the follow-up were taken into account in this analysis. Raw data was extracted in order to estimate the relative risk and the corresponding 95% confidence interval (95% CI). Subgroup analysis of age was performed to eliminate the effect of age on the results. Statistical heterogeneity was measured using the I2 index and Cochran's Q test. RESULTS: Eight studies were enrolled in this analysis (3237 events and 13165 participants), and the pooled relative risk for the 70-80 years old subgroup was 2.00 (95% CI=1.79-2.23). CONCLUSION: Relatively, there is a higher risk of cognitive impairment at the end of follow-up in younger adults with olfactory impairment at the beginning of follow-up. The length of follow-up has a little effect on the relative risk.

[Predictors of posttreatment olfactory improvement in patients with postviral olfactory dysfunction].

Objective:To analyzed the results of olfactory function test in patients with post-viral olfactory dysfunction（PVOD）, and evaluated the prognostic factors, so as to provide a basis for clinical diagnosis and treatment. Methods:This study included patients who were diagnosed with PVOD at least one year ago in Beijing Anzhen Hospital and whose telephone interviews of subjective olfactory function were available. The general condition of the patients, the results Sniffin' Sticks olfactory test and the event-related potentials（ERPs） were analyzed in different improvement groups. This study retrospectively analyzed PVOD patients treated in the outpatient department of Beijing Anzhen Hospital. They were given olfactory training for 4 months. The Sniffin' Sticks test was performed on the patients before and after the treatment. The Sniffin' Sticks test and event-related potentials（ERPs） results were used to evaluate the prognostic factors. Results:In this study, the olfactory improvement rate of 63 PVOD patients was 52.38%（33/63）. Compared to the non-improvement group, the course of disease in the group with improved subjective olfactory function was significantly shorter（P<0.001）, the initial olfactory function was significantly better（P<0.001）, and the olfactory threshold was much lower（P<0.001）. The presence of olfactory event-related potentials and trigeminal ERPs（tERPs） were 52.38%（33/63） and 87.30%（55/63）, respectively. The presence of oERPs in the olfactory function improvement group was significantly higher than that in the non-improvement group（P<0.05）, but there was no difference in the presence of tERPs（P>0.05）. Latency of N1 and P2 waves in oERPs with improvement group（ON1L, OP2L） were longer than those in the non-improvement group（P<0.05）, N1 and P2 wave amplitudes（ON1A, OP2A） had no difference（P>0.05）. The N1 and P2 amplitudes and latency of tERPs showed no difference between the two groups. Multivariate Logistic regression analysis showed that threshold value before treatment（OR=21.376, 95%CI: 2.172-210.377, P=0.009）; ON1L（OR=0.994, 95%CI: 0.988-0.999, P=0.029） and course of disease（OR=0.607, 95%CI: 0.405-0.920, P=0.016） was significantly associated with olfactory prognosis. Conclusion:The course of olfactory dysfunction, the severity of olfactory dysfunction, the threshold of olfactory function, and the latency of N1 wave of oERPs can be used to evaluate the prognosis of PVOD patients. However, age, olfactory discrimination, recognition ability, oERPs amplitude and tERPs wave value had less prognostic value.

Gastroesophageal Reflux Disease: A Cause for Eustachian Tube Dysfunction in Obstructive Sleep Apnea.

OBJECTIVES: To explore the effect of gastroesophageal reflux disease (GERD) on Eustachian tube function in patients with obstructive sleep apnea (OSA). METHODS: This was a cross-sectional study. The patients were divided into 4 groups according to OSA and GERD: OSA+GERD group; OSA-only group; GERD-only group; and normal control group. RESULTS: There were no differences among the 4 groups regarding age, sex, smoking history, and alcohol history (all P > .05). The patients in the OSA and OSA+GERD groups had a significantly larger body mass index than those in the control and GERD-only groups (all P < .05). The proportions of patients with abnormal ETS-7 and ETD-Q results were higher in the GERD and OSA+GERD groups compared to the control group (P < .008). There were no significant differences in ETS-7 and ETD-Q between the control and the OSA-only groups (P > .008). The multivariable analysis showed that only GERD was independently associated with abnormal ETS-7 results (odds ratio = 3.090, 95% CI: 1.332-7.169, P = .009). CONCLUSION: Given the high concomitance rate in patients with OSA, GERD might be an important association factor of Eustachian tube dysfunction in patients with OSA.

Three-dimensional assessment of pharyngeal volume and cross-sectional area in Chinese infants and preschool children.

OBJECTIVE: The cross-sectional area (CSA) and the volume of the pharyngeal airway normative reference data aren't established, although they are closely associated with the pathogenesis of obstructive sleep apnea syndrome (OSAS) in infants and preschool children. Our objective is to measure the cross-sectional area (CSA) and volume of pharyngeal airway subregions and investigate the effects of age and sex in infants and preschool children using computerized tomography (CT). METHODS: After applying strict inclusion criteria, 57 infants and preschool children (27 females, 30 males) aged from 1 day to 72 months who underwent maxillofacial CT scans due to trauma were selected. The sample was stratified into three age groups (1 day-24 months, 25-48 months, and 49-72 months). The CSA and the volume of the naso-, palato-, glosso-, and laryngopharyngeal airway were calculated using a 3-dimensional image processing software. Linear regression analysis was performed to express the effect of age, height, and weight. One-way analysis of covariance with height as a covariate was used to analyze the statistical significance of the difference between males and females within each age group. RESULTS: The CSA and volume of all pharyngeal airway subregions increased with age, height, and weight (P < 0.05) in children under 6 years old. Multiple linear regression analysis showed an age effect, identified in all measurements (P < 0.001), whereas no height or weight effect were found. There were no differences in any measurements between males and females within each age group. CONCLUSION: The normative reference data of CSA and volume of pharyngeal airway subregions were established after applying strict inclusion and exclusion criteria in infants and preschool children. Results may be useful in screening and assist in the timely diagnosis and management of pediatric OSAS.

Assessment of gustatory function in aging people using event-related potentials.

Gustatory dysfunctions are more frequent than other chemosensory dysfunctions in aging people. Gustatory event-related potentials (ERPs) has been suggested as a reliable and effective approach for assessing gustatory functions in young and middle subjects, but has rarely been investigated in aging people, leaving influencing factors of ERPs in that population not completely understood. In this study, we analyzed gustatory ERPs results of aging participants and characterized potential impacting factors, including age, sex, BMI, drinking, smoking, hypertension, diabetes, cognition and psychophysical test scores of gustation and olfaction. Our results revealed three components (P1, N1 and P2) in gustatory ERPs upon salty stimulation. Significant differences between responses collected from different recording electrodes were observed: minimum latencies and maximum amplitudes of P1 were detected at frontal electrode, and maximum amplitudes of N1 and P2 were detected at central and centro-parietal electrodes, respectively. Major cortical sources of components P1, N1 and P2 were located at bilateral insula, frontal operculum, and orbitofrontal cortex. Diabetes was positively associated with latencies of P1. Sex was positively associated with amplitudes of P1, N1 and P2. Hypertension was negatively associated with amplitudes of P1 and P2. In conclusion, gustatory ERPs in aging people exhibited a specific topographical distribution, represented by sex-related differences and negative impacts of diabetes and hypertension.

Evaluation of idiopathic olfactory loss with chemosensory event-related potentials and magnetic resonance imaging.

BACKGROUND: Idiopathic olfactory loss (IOL) accounts for a sizable fraction of olfactory dysfunction, but very little is known about its etiology and electrophysiological changes in the olfactory pathway. METHODS: We analyzed the physiology of IOL using chemosensory event-related potentials (ERPs) (olfactory and trigeminal: oERP and tERP) and olfactory pathway magnetic resonance imaging (MRI) measured in adult patients with IOL and healthy controls. Subjective olfactory function was measured by Toyota and Takagi (T&T) olfactometry and Sniffin' Sticks (SS). RESULTS: Olfactory function was worse in patients with IOL compared to controls (T&T, p < 0.001; SS, p < 0.001). oERPs could be evoked in 17 IOL patients. Signals in these patients showed lower amplitude in the N1 and P2 waves than controls (p < 0.05 for both), but there were no difference in latency between the 2 groups (p > 0.05). tERP were detected in all patients and controls; there were no differences in latency and nor amplitude between the 2 groups (p > 0.05). The olfactory bulb (OB) volume was significantly smaller in the IOL group than controls (p < 0.001), but there was no difference in the olfactory sulcus depth between groups (p > 0.05). Better olfactory function was associated with increasing magnitude of N1 amplitude in oERPs (p < 0.05) and increasing OB volume (p < 0.05). CONCLUSION: IOL patients show neurophysiologic deficits and some anatomic differences compared to healthy controls.

Olfactory cortex and Olfactory bulb volume alterations in patients with post-infectious Olfactory loss.

Upper respiratory tract infection (URI) is one of the most common etiology of olfactory loss. Previous studies demonstrated that both olfactory bulb (OB) volume and sulcus (OS) depth decreased in patients with post-infectious olfactory loss (PIOL) compared to normal controls. The aim of our study was to observe alterations of central olfactory pathways in patients with PIOL. T1 weighted magnetic resonance images were acquired in 19 PIOL patients and 19 age- and sex-matched control subjects on a 3 T scanner. Voxel-based morphometry (VBM) was performed using VBM8 toolbox and SPM8 in a Matlab environment. We also analyzed OB volume in coronal T2-weighted images. Whole-brain analysis revealed a significant gray matter volume loss in the right orbitofrontal cortex (OFC) in patients group. Further analysis with region of interest exhibited a significant negative correlation between gray matter volume in right OFC as well as OB volume and the duration of olfactory loss in these patients (r = -0.566 and r = -0.535 both P < 0.05, respectively). In conclusion, the morphological alterations in the right OFC and OB might contribute to the pathogenic mechanism of olfactory dysfunction after upper respiratory tract infection.

Linear dimensions of normal upper airway structure by magnetic resonance imaging in Chinese Han infants and preschool children.

OBJECTIVES: To establish normative data of upper airway structure in Chinese Han infants and preschool children. METHODS: Magnetic resonance imaging (MRI) scans of 521 Chinese Han infants and preschool children (225 girls, 296 boys) aged from 1 day to 72 months were selected from the children who underwent head MRI at the Capital Institute of Pediatrics Affiliated Children Hospital, Beijing, China. No subjects had sleep-disordered breathing or associated conditions that may have affected the upper airway anatomy. The upper airway dimensions and surrounding soft tissue sizes were measured along the mid-sagittal and axial images. RESULTS: On images from the mid-sagittal image, the normative values of the following were obtained for all age group: thickness of the adenoid and nasopharyngeal area, length and thickness of the soft palate, length and height of the tongue, length of upper airway, distance between the mental spine and clivus, and the adenoid oblique width, soft palate oblique width, and tongue oblique width along the mental spine-clivus line. Normative values of the mean tonsillar width and intertonsillar space on the axial images were also obtained. There were no differences in any measurements between boys and girls in either infants or preschool children. Older children had larger airway dimensions, as expected. CONCLUSION: Normative values for upper airway structure in Chinese Han infants and preschool children assessed by MRI were established. The upper airway dimension and surrounding soft tissues size, including soft palate, adenoid, tongue, and tonsils, were increased with age. There were no gender differences during the first six years of life. These data may prove useful when studying airway disease in Chinese Han children.

Olfactory impairment and the risk of cognitive decline and dementia in older adults: a meta-analysis / Distúrbio olfativo e o risco de declínio cognitivo e demência em idosos: uma metanálise

Abstract Introduction The prediction of the impact of olfactory impairment on cognitive decline in older adults has been different among different age groups. Objective This meta-analysis sought to estimate the predictive power of olfactory impairment on cognitive decline during follow-up in older adults of different ages. Material and methods A medical literature search was carried out using these databases for eligible studies: MEDLINE, COCHRANE and EMBASE. Studies recording olfaction and cognition detection at the beginning and end of the follow-up were included in the preliminary screening. The medical records of older adults without cognitive impairment at the beginning of the follow-up were taken into account in this analysis. Raw data was extracted in order to estimate the relative risk and the corresponding 95% confidence interval (95% CI). Subgroup analysis of age was performed to eliminate the effect of age on the results. Statistical heterogeneity was measured using the I 2 index and Cochran's Q test. Results Eight studies were enrolled in this analysis (3237 events and 13165 participants), and the pooled relative risk for the 70-80 years old subgroup was 2.00 (95% CI = 1.79-2.23). Conclusion Relatively, there is a higher risk of cognitive impairment at the end of follow-up in younger adults with olfactory impairment at the beginning of follow-up. The length of follow-up has a little effect on the relative risk.

Resumo Introdução A previsão do impacto do comprometimento olfativo no declínio cognitivo em idosos tem sido distinta entre diferentes faixas etárias. Objetivo Esta metanálise buscou estimar o poder preditivo do comprometimento olfativo no declínio cognitivo durante o seguimento em idosos de diferentes idades. Material e métodos Foi feita uma pesquisa na literatura médica nos seguintes bancos de dados para estudos elegíveis: Medline, Cochrane e Embase. Os estudos que registraram olfação e detecção de cognição no início e no fim do seguimento foram incluídos na triagem preliminar. Os prontuários médicos de idosos sem comprometimento cognitivo no início do seguimento foram considerados nessa análise. Os dados brutos foram extraídos para estimar o risco relativo e o intervalo de confiança de 95% (IC95%) correspondente. A análise de subgrupos da idade foi feita para eliminar o efeito da idade nos resultados. A heterogeneidade estatística foi medida utilizando o índice I2 e o teste Q de Cochran. Resultados Oito estudos foram incluídos nesta análise (3.237 eventos e 13.165 participantes) e o risco relativo combinado para o subgrupo de 70 a 80 anos foi de 2,00 (IC95% = 1,79-2,23). Conclusão Relativamente, existe um risco maior de comprometimento cognitivo no fim do seguimento em adultos mais jovens que se se apresentam com comprometimento olfativo no início do seguimento. A duração do seguimento tem um pequeno efeito no risco relativo.