Search

Background: Evidence suggests that olfactory impairment (OI) may be a degenerative neurologic complication of diabetes; however, the association is not yet well established. The objective of this work was to systematically review existing literature on the association between diabetes and OI in adults, with meta‐analysis of evaluable studies. Methods: A literature search encompassing 358 abstracts from the last 75 years in PubMed, EMBASE, and Cochrane was performed. English‐language articles investigating adults with diabetes and OI in comparison to control groups with original data and ≥7 subjects were included. The Newcastle‐Ottawa scale was applied for quality assessment. Two investigators independently reviewed all articles. For meta‐analysis, the odds ratio of OI in diabetes compared with control groups was calculated using the fixed effects model. Results: The initial search yielded 358 abstracts, from which 21 articles were reviewed and 11 articles (n = 6,747) were included. Studies included were case‐control (64%) or cross‐sectional (36%) with evidence level 3b. On the Newcastle‐Ottawa scale, the mean quality assessment score for case‐control and cross‐sectional studies was 7.4 (maximum of 9) and 7.0 (maximum of 10), respectively. A statistically significant association between diabetes and olfaction compared with controls was found in 6 (55%) of the 11 articles. Four studies were eligible for meta‐analysis, which yielded an overall odds of having OI with diabetes as 1.58 times more likely than in control groups (95% CI [1.16, 2.16]; I2 = 10.3%). Conclusions: The reviewed studies support a significant association between diabetes and OI. Further studies are warranted to characterize this association. Level of Evidence: 3a [ABSTRACT FROM AUTHOR]

Background: In this work we assess the association between olfactory dysfunction and cognition in a nationally representative sample of older adults in the United States. Methods: Participants aged ≥60 years (n = 1236) from the 2013–2014 National Health and Nutritional Examination Survey underwent both olfactory and cognitive testing. Olfaction was assessed by both objective test (8‐odor Pocket Smell Test: smell impairment defined as score ≤2) and self‐report. Cognitive assessment consisted of the Digit Symbol Substitution Test (DSST), the Animal Fluency Test, and the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). Regression models were used to examine the association between olfaction and cognition while adjusting for demographics, cardiovascular factors, and associated medical history. Results: The prevalence of smell impairment in US older adults was 18.0% (95% confidence interval [CI], 14.0‐22.0%) and 22.0% (95% CI, 18.5‐25.6%) based on objective smell test and self‐report, respectively. In a multivariate model adjusted for relevant factors, low smell test scores were consistently associated with low scores on cognitive assessments, with a DSST score difference of −1.5 (95% CI, −2.2 to −0.8), Animal Fluency Test score difference of −0.4 (95% CI, −0.7 to −0.1), and CERAD Word List score difference of −0.4 (95% CI, −0.6 to −0.2) per 1‐point decrease in smell test score. There was no association between self‐reported smell impairment and cognition. Conclusion: Objectively measured olfactory dysfunction is independently associated with cognitive impairment. These findings are consistent with previous studies and suggest the utility of objective olfactory tests as an indicator for cognitive impairment as compared with self‐reported olfactory dysfunction, which is an uncertain indicator. [ABSTRACT FROM AUTHOR]

Background/objectives: Loss of olfactory function is largely found with aging. Such a reduction in olfactory function affects quality of life and enhances likelihood of depressive symptoms. Furthermore, it has been shown that reduction in olfactory function is associated with cognitive impairment and several diseases such as major depression. Because several studies suggest that discontinuous exposure to odors may improve general olfactory function, the primary aim of this study was to investigate whether such "olfactory training" has positive effects on subjective well-being and cognitive function.Design: We performed a controlled, unblinded, longitudinal study SETTING: The study took place at an outpatients' clinic of a Department of Otorhinolaryngology at a Medical University.Participants: A total of 91 participants (age 50 to 84 years) completed testing. They were randomly assigned to an olfactory training (OT) group (N = 60) and a control group (N = 31). The study included two appointments at the Smell and Taste Clinic.Measurements: Olfactory and cognitive function as well as subjective well-being was tested using standardized tests.Intervention: During the 5-month interval between sessions, the OT group completed daily olfactory exposure. During the same time, the control group completed daily Sudoku problems.Results: Analyses show a significant improvement of olfactory function for participants in the OT group and improved verbal function and subjective well-being. In addition, results indicated a decrease of depressive symptoms.Conclusion: Based on the present results, OT may constitute an inexpensive, simple way to improve quality of life in older people. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Drug-induced parkinsonism ( DIP) is common, and the motor symptoms can be indistinguishable from Parkinson's disease ( PD). When symptoms persist after drug withdrawal, this may represent 'unmasking' of underlying PD. We previously reported that hyposmia, a common nonmotor feature of PD, was associated with persistent DIP. Here, we report on a series of 33 consecutive patients who underwent dopamine transporter imaging to evaluate DIP. We examined the clinical correlates of underlying dopaminergic denervation by comparing subjects with normal and abnormal scans. Imaging was abnormal in 7 of 33 (21%) cases. Motor features were similar in patients with normal and abnormal scans. Olfactory testing was available for 30 subjects and was concordant with imaging in 27 of 30 (odds ratio = 63; 95% confidence interval: 4.8-820; P = 0.002). Olfactory testing may be a simple screen to help identify DIP patients with underlying dopaminergic denervation, consistent with unmasking of incipient PD. [ABSTRACT FROM AUTHOR]

Background Chronic rhinosinusitis (CRS) is a common inflammatory condition and a major cause of olfactory loss. Olfactory dysfunction has been associated with reduced olfactory bulb (OB) volume and gray matter (GM) density in the olfactory-related brain areas. The aim of this study was to investigate brain GM structural and OB volume alterations in patients with CRS. Methods Structural brain images were collected from 21 CRS patients and 31 healthy controls on a 3-T scanner. Voxel-based morphometry (VBM) was performed to investigate GM. Olfactory bulb volumes were measured using AMIRA software. Psychophysical olfactory testing for odor threshold (T) and identification (I) was performed using the Sniffin' Sticks battery. Results CRS patients had significantly lower scores for Sniffin' Sticks olfactory tests than controls ( p < 0.001 for T, I, and combined T and I [TI] scores). Region-of-interest analyses revealed no difference in GM volume between CRS patients and healthy controls; however, in CRS patients with severe olfactory dysfunction, GM reduction was observed in the gyrus rectus, orbitofrontal cortex, thalamus, and the insula. In addition, no difference was observed for OB volume in CRS patients compared with healthy controls. Conclusion In this study we identified a reduction in gray matter in olfactory brain regions in CRS patients with severe olfactory dysfunction. [ABSTRACT FROM AUTHOR]

Background Olfactory function deteriorates in patients with severe obstructive sleep apnea syndrome (OSAS). The effect of positive airway pressure (PAP) therapy on olfactory function has not been investigated before. In this study, we aimed to investigate the role of PAP therapy on olfactory impairment in patients with OSAS. Methods Thirty patients who had OSAS and planned for PAP therapy were included in the study. All participants underwent a detailed otorhinolaryngological examination and polysomnography. The 'Sniffin' Sticks' test was used for the analysis of olfactory function. The participants underwent the smell test before the PAP therapy, and about 3 months after the therapy. Pretreatment and posttreatment results were compared. Results The pretreatment and the posttreatment apnea-hypopnea index (AHI) were 57.6 ± 29.8/hour and 9.5 ± 7.9/hour, respectively. Odor threshold (OT), odor discrimination (OD), odor identification (OI), and threshold-discrimination-identification (TDI) scores significantly increased after PAP therapy ( p = 0.001, p = 0.002, p = 0.001, and p = 0.001, respectively). The pretreatment and posttreatment total TDI scores were 28.48 ± 4.71 and 32.50 ± 3.88, respectively ( p = 0.001). Conclusion This study demonstrates olfactory dysfunction in patients with OSAS. We achieved a significant improvement in olfactory function of patients with OSAS after PAP therapy. Further studies are needed to illuminate the pathogenesis of olfactory dysfunction in OSAS, and the role of PAP therapy on olfactory improvement. [ABSTRACT FROM AUTHOR]

Background Vitamin B12 plays a major role in the maintenance of central and peripheral nervous systems. Vitamin B12 deficiency may affect the spinal cord, brain, optic nerve, and peripheral nerve functions; however, the effect of vitamin B12 deficiency on olfactory function has not been studied, so our study aimed to investigate that. Methods Thirty-nine patients with low vitamin B12 levels and 34 controls were included in the study. All participants had detailed otorhinolaryngological examinations and laboratory tests. The Sniffin' Stick test was used for analysis of olfactory function. The 2 groups were compared for smell test results. Correlations of smell test results with demographic and laboratory data were investigated in the vitamin B12-deficient group. Results The threshold discrimination identification scores were (mean ± standard deviation) 28.04 ± 5.58 and 35.10 ± 2.84 in the vitamin B12-deficient and control groups, respectively ( p < 0.001). In the vitamin B12-deficient group, hyposmia and anosmia were evident in 56.4% and 5.1% of the patients, respectively, but no subjects in the control group had olfactory dysfunction ( p < 0.001). Correlation analysis showed that age and odor identification score showed a negative correlation ( p < 0.001); however, there was a positive correlation between threshold, discrimination and identification (TDI) score and vitamin B12 levels. Conclusion In this study, we showed for the first time that olfactory dysfunction may be present in patients with vitamin B12 deficiency. Apart from a negative correlation of age with odor identification score, none of the other parameters studied showed correlations with olfactory dysfunction. [ABSTRACT FROM AUTHOR]

Chronic renal disease is known to alter olfactory function, but the specific changes induced in olfactory organs during this process remain unclear. Of the uraemic toxins generated during renal disease, high levels of urea are known to induce hyposmic conditions. In this study, the effects of environmental exposure to elevated concentrations of urea (7, 13.5 and 20 g L-1) on the sensory mucosa of zebrafish in acute toxicity and chronic toxicity tests were described. It was observed that lamellae maintained structural integrity and epithelial thickness was slightly reduced, but only following exposure to the highest concentrations of urea. Panneuronal labelling with anti-Hu revealed a negative correlation with levels of urea, leading to investigation of whether distinct neuronal subtypes were equally sensitive. Using densitometric analysis of immunolabelled tissues, numbers of Gα olf-, TRPC2- and TrkA-expressing cells were compared, representing ciliated, microvillous and crypt neurons, respectively. The three neuronal subpopulations responded differently to increasing levels of urea. In particular, crypt cells were more severely affected than the other cell types, and Gα olf-immunoreactivity was found to increase when fish were exposed to low doses of urea. It can be concluded that exposure to moderate levels of urea leads to sensory toxicity directly affecting olfactory organs, in accordance with the functional olfactometric measurements previously reported in the literature. [ABSTRACT FROM AUTHOR]

Background and purpose Olfactory dysfunction is common in Parkinson's disease ( PD) and it is one of the earliest non-motor symptoms. A few studies have suggested that deep brain stimulation of the subthalamic nucleus ( STN- DBS) could improve olfactory function. Our aim was to evaluate the acute effect of bilateral STN- DBS on a commonly used smell test in PD patients. Methods Fifteen PD patients who underwent bilateral STN- DBS and 15 controls were recruited. Patients and controls were tested for odor identification. Results No statistical differences were documented between ON and OFF STN- DBS acute stimulation concerning olfaction. Controls presented a better performance for olfactory identification than patients. Conclusions Our exploratory study did not support that bilateral STN- DBS could have an acute effect on olfactory function in PD patients. [ABSTRACT FROM AUTHOR]

Background Olfactory dysfunction is common among patients with chronic rhinosinusitis and has a negative impact upon quality of life. Olfactory dysfunction can be both subjective and objective and appears to be more predominant in patients with concomitant nasal polyposis. The efficacy of medical interventions on olfaction among patients with CRS with nasal polyposis (CRSwNP) is not well known. Our aim was to perform a systematic review with meta-analysis of the efficacy of medical therapies on objective and subjective hyposmia among patients with CRSwNP. Methods Olfaction specific outcomes from randomized controlled trials evaluating medical interventions on patients with CRSwNP were evaluated. Interventions included corticosteroids, antibacterials, antifungals, diuretics, herbals and anti-immunoglobulin E (IgE) medications. Results A total of 28 randomized control trials evaluation olfaction in CRSwNP was identified and systematically reviewed. Sufficient data for meta-analysis was retrieved for 5 trials. In the meta-analysis, oral steroids showed significant improvement in subjective olfaction scores compared to placebo (standardized mean difference [SMD] −2.22; 95% confidence interval [CI], −3.94 to −0.49). Oral steroids also showed significant improvement in objective olfaction scores compared to placebo (SMD 0.65; 95% CI, 0.28 to 1.01). In the systematic review, both topical steroids and combined topical and oral steroid groups showed overall improvement in subjective olfaction outcomes. Antibacterials, antifungals, herbals, and anti-IgE medications had no impact on overall olfaction scores. Conclusion The results of this meta-analysis demonstrated that oral and topical steroids significantly improve olfaction in patients suffering from CRSwNP. [ABSTRACT FROM AUTHOR]

The article presents abstracts on clinical papers and medical topics which include headache and pain mechanisms, miscellaneous clinical headache topics and study on electroencephalogram variations in pediatric migraines and tension-type headaches.

An effective surgical procedure for the removal of suspected neoplasms of the scent gland in Mongolian gerbils (Meriones unguiculatus) is presented. Information on the range of neoplastic processes and their clinical behaviour, based on the excision and morphological examination of localised scent gland abnormalities of 16 privately owned male gerbils is also provided. This report includes the first description of scent gland epitheliomas. [ABSTRACT FROM AUTHOR]

Background Olfactory neuroblastoma is a rare paranasal sinus malignancy. The traditional approach was craniofacial resection (CFR) and then postoperative radiotherapy until 1998. This review will chart development of a new protocol. Methods This ethics-approved audit evaluated the number of new patients diagnosed with olfactory neuroblastoma, with information relating to patient, disease, and treatment factors noted. Results There were 24 eligible patients, 16 men, 8 women, 7 Kadish stage B, 17 stage C. The planned treatment was: chemotherapy (cisplatin/etoposide) and determine treatment dependent on response in 6 patients, surgery and radiotherapy in 16 patients, and single-modality treatment only (surgery, radiotherapy 1) in 2 patients. Surgery to radiotherapy occurred in 17 patients. With salvage treatment ultimate local control was 79%. Conclusions There was a higher local control in those patients who had surgery; abandoning this may carry a higher risk of local failure. The use of response to chemotherapy to determine local treatment remains experimental. © 2010 Wiley Periodicals, Inc. Head Neck, 2010 [ABSTRACT FROM AUTHOR]

Background. The purpose of our study was to assess the long-term results in the management of patients with esthesioneuroblastoma. Methods. A total of 28 patients were retrospectively reviewed to analyze their clinical features, treatment outcomes, pattern of failures, and course of the disease. Results. The patients were classified as 2 patients with T1, 10 patients with T2, 10 patients with T3, and 6 patients with T4; the results of all were included in this study. Twenty-six patients underwent surgery and 23 had postoperative radiotherapy over the tumor bed, only 9 had radiotherapy over the nodes. The average follow-up was 99.11 months. Fifteen-year and 20-year disease-specific and disease-free survival rates were 88.6% to 66.4% and 59.6% to 29.8%, respectively. Six patients had recurrences and 60% of them occurred more than 10 years after treatment. In the first decade, nodal recurrences appeared earlier than local ones when patients with N0 did not undergo neck irradiation. Conclusion. Surgery on patients with T presentations and adjuvant radiotherapy on T and N0 neck presentations seem to be essential to treat esthesioneuroblastoma. A follow-up for a minimum of 20 years is necessary to ensure complete cure. [ABSTRACT FROM AUTHOR]