• Journal of Korean Neurosurgical Society
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• v.29 no.12
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• pp.1570-1576
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• 2000

Objective : To evaluate objectively the sites of injury in patients with posttraumatic olfactory deficits and to suggest the diagnostic procedure for evaluation of posttraumatic anosmia. Methods : Ten patients with posttraumatic olfactory dysfunction were examined by means of olfactory testing, sinoscopy, contrast filled paranasal sinus computed tomography(contrast filled PNS CT) and magnetic resonance imaging(MRI). Five normal persons without olfactory dysfunction were also evauluated. The aerodynamic patency of olfactory cleft was examined by contrast filled PNS CT. The olfactory system(oflactory bulbs, olfactory tracts, inferior frontal region, hippocampi, or temporal lobes) was investigated in detail with MRI. The difference in the size of the olfactory bulb between normal volunteers and anosmic patients was evaluated by Student's t test. Results : Contrast filled dynamic CT scan was useful method for the evaluation of dynamic patency of the olfactory cleft. Paranasal CT scan of the all anosmic patients showed dynamic reflux of contrast media in olfactory cleft on valsalva maneuver. For the largest cross-sectional area and great height, the difference in olfactory bulb size between normal volunteers and patients was statistically significant(p<0.001) in MRI study. Conclusion : Posttraumatic anosmia was completely evaluated by olfactory testing, sinoscopy, and contrast filled CT scan for differentiation between conductive type and neurogenic type. Neurogenic anosmia was confirmed by perfect localization with MRI study.

• BMB Reports
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• v.54 no.6
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• pp.295-304
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• 2021

Olfactory neuropathology is a cause of olfactory loss in Alzheimer's disease (AD). Olfactory dysfunction is also associated with memory and cognitive dysfunction and is an incidental finding of AD dementia. Here we review neuropathological research on the olfactory system in AD, considering both structural and functional evidence. Experimental and clinical findings identify olfactory dysfunction as an early indicator of AD. In keeping with this, amyloid-β production and neuroinflammation are related to underlying causes of impaired olfaction. Notably, physiological features of the spatial map in the olfactory system suggest the evidence of ongoing neurodegeneration. Our aim in this review is to examine olfactory pathology findings essential to identifying mechanisms of olfactory dysfunction in the development of AD in hopes of supporting investigations leading towards revealing potential diagnostic methods and causes of early pathogenesis in the olfactory system.

• Animal cells and systems
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• v.6 no.4
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• pp.287-292
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• 2002

Functional characterization of sex pheromones in olfactory responses is essential for the study of chemical communications in amphibians. Using Y-maze olfactory preference tests, we have investigated the olfactory res-ponses of male and female red-spotted newts, Notophthalmus viridescens, to the crude extracts of the opposite sex's genial and cloacal pheromones. Both male and female cloacal pheromone extracts caused the opposite sex to initiate olfactory responses by leaving the starting area in the Y-maze, but only subject males exposed to female cloacal pheromone extracts completed olfactory choice by entering the side arm of the Y-maze which received the pheromones. For genial pheromone extracts, only female genial pheromone extracts induced initial olfactory responses from test males. Neither male nor female genial pheromone extracts made the oppo-site sex complete olfactory choice. Pre-exposure of test females to male pheromone extracts increased the likelihood of initial olfactory responses. The latency for initial olfactory responses of test females that were previously exposed to male genial extracts was significantly shorter than that of control females.

• ETRI Journal
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• v.37 no.1
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• pp.88-96
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• 2015

The purpose of this study is to design an authoring tool and a corresponding device for an olfactory display that can augment the immersion and reality in broadcasting services. The developed authoring tool allows an olfactory display to be properly synchronized with the existing video service by applying the standardized format using ISO/IEC 23005 (MPEG-V) and the corresponding developed scent display device. To propose the proper data format for the olfactory display, we have analyzed both the multimodal combination and the cross-modality related to the olfactory display. From the results of the analysis, we derived a set of olfactory parameters for the olfactory display that are related to emotion. The analyzed parameters related to emotion in an olfactory display are synchronization, scent intensity, scent persistence, and hedonic tone. These parameters should be controlled so that the olfactory display can be in harmony with the existing media to augment emotion. In addition, we developed a scent display device that can generate many kinds of scents and that satisfies design conditions for olfactory parameters that are for use with broadcasting services.

• Speech Sciences
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• v.7 no.1
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• pp.65-75
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• 2000

The present study attempted to determine the effect of olfactory stimulation on word retrieval deficit in Korean aphasics. Eleven nonfluent and 9 fluent aphasic patients served as subjects. The 20 subjects' age ranged from 14 to 65 with the mean of 43.0 (SD: 17.6). A neurologist examined them and diagnosed that they had no visual, auditory, and olfactory impairment. The study consisted of 2 experiments: Experiment I included visual stimulation while experiment II included visual and olfactory stimulation. The subjects were presented with 19 pictures for them to name in the experiment I, whereas they were exposed to the 19 pictures along with the corresponding olfactory stimulus in the experiment II. The 19 items included soy sauce, chilly pepper, Kimchi, chewing gum, cigarette (smoked), soybean paste, lemon, banana, alcohol (wine), apple, fish, vinegar, cuttlefish (dried), milk, rose, sesame oil, melon, coffee, and perfume. The results were as follows: First, olfactory stimulation tended to improve aphasics' word retrieval deficit although the improvement was not statistically significant. Second, the nonfluent aphasics seemed to take more advantage from olfactory stimulation compared to the fluent aphasics. Third, olfactory stimulation (olfactory + visual) did not produce a different naming performance compared to visual stimulation in the pre- and post-test when the pre- and post-test was composed of naming tasks through auditory + visual stimulation. Fourth, the fluent aphasics performed better with unpleasant olfactory stimulus while the nonfluent aphasics performed better with pleasant olfactory stimulus.

• Journal of Oral Medicine and Pain
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• v.26 no.4
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• pp.309-318
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• 2001

The purposes of the study were (1) to evaluate the olfactory identification ability in those who have bad breath, (2) to determine the olfactory detection threshold for methyl mercaptan in normal subjects and those who have bad breath, and (3) to evaluate the effect of oral hygiene care on the olfactory detection threshold for methyl mercaptan. Sixteen male subjects with bad breath (male odor group), 9 male subjects without bad breath (male non-odor group), and 10 female subjects without bad breath (female non-odor group) were included for the study. Olfactory identification ability was assessed by administrating the Cross-Cultural Smell Identification Test (CC-SIT), and the olfactory detection threshold for methyl mercaptan was measured by two-alternative forced-choice single-staircase detection threshold procedure in a double-blinded condition. The geometric mean of the last four staircase reversal points of a total of seven reversals is used as the threshold. For the male odor group, after 1 month of intensive oral hygiene care for reducing oral volatile sulfur compounds (VSC) concentration, the olfactory detection threshold for methyl mercaptan was measured again and compared to the initial value. The ANOVA was used to test the group difference of olfactory threshold and olfactory identification ability and the paired t-test was used to test the difference of olfactory threshold between before and after reduction of oral VSC in male odor group. The results were as follows : 1. There was no significant difference in olfactory identification ability among those who have bad breath and normal male or female subjects. 2. The olfactory detection threshold for methyl mercaptan was about 8.4 ppb in normal male and female. 3. There was a tendency that male subjects with bad breath showed a higher olfactory detection threshold for methyl mercaptan when compared to those of no bad breath. 4. The olfactory detection threshold for methyl mercaptan returned to a normal level after 1 month of intensive oral hygiene care for reducing oral VSC.

• Animal cells and systems
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• v.3 no.3
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• pp.259-267
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• 1999

The expression of the neural cell adhesion molecule-180 (NCAM-180), which accumulates at contact sites between cells and may be responsible for the stabilization of cell contacts, was studied in the olfactory system and retina of developing and adult rats. From embryonic day 12 onwards, which was the earliest stage examined, the NCAM-180 pathway directing to the presumptive olfactory bulb was observed. In later stages, olfactory neurons and fasciculating axons in the olfactory epithelium and nerve fiber layer and glomeruli of the olfactory bulb expressed NCAM-180. From postnatal day 0, immunolabelling pattern of the olfactory epithelium and olfactory bulb were the same as that during later stages. NCAM-180 immunoreactivity was present on differentiating retinal cells and persisted on those cells throughout adulthood. However, contrary to the olfactory nerve which remained detectable in the adult, the optic nerve was only transiently expressed with NCAM-180 and was no longer detectable in the adult. The presence of NCAM-180 in olfactory tissues suggests their possible role in pathfinding, differentiation, fasciculation and synaptic plasticity. The continued presence of NCAM-180 in the olfactory system examined may underlie its continuous cell turnover and regenerative capacity. The continuous expression of NCAM-180 in ganglion cells, bipolar cells and photoreceptor cells, also suggests potential regenerating capability and some plastic functions for these cells in the adult. Since the expression of NCAM-180 by the optic nerve was restricted to the period of special histogenetic events, for example, during axonal growth and synaptogenesis, it is possible that the lack of NCAM-180 in the adult optic nerve might cause a nonpermissive environment for the regeneration and result in regenerative failure of this system.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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• v.62 no.2
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• pp.75-81
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• 2019

The objective of this study was to perform a systematic review of the literature for application of intranasal sodium citrate in the patients with olfactory dysfunction to help determine the sodium citrate treatments for this condition. Two authors independently searched the data base (Medline, Scopus, and the Cochrane database) for relevant studies from inception to January 2018. Included studies were randomized controlled studies published in English comparing topical sodium citrate application (treatment group) with saline (control group) in patients who had olfactory dysfunction. Outcomes of interest included the change of olfactory identification and threshold during 2 hours post-treatment. Three studies were enrolled in the meta-analysis. Compared with control group, treatment group did not increase posttreatment score of olfactory identification [standardized mean difference (SMD)=-0.03; 95% confidence interval (CI)=-0.29-0.24; I²=0%] and olfactory threshold (SMD=0.18; 95% CI=-0.09-0.45; I²=0%) significantly. In the degree of pre-post improvement of two outcomes, although treatment group statistically showed the significant improvement in olfactory threshold (SMD=0.30; 95% CI=0.05-0.55; I²=17%), the clinical significance of this outcome was meaningless. Similarly, there was no significant difference in olfactory identification between two groups (SMD=0.17; 95% CI=-0.11-0.45; I²=22%). Unlike the recent favorable results, our summated results presented the uselessness for the local application of sodium citrate in improving patient's olfactory function. However, we also had some limitation such as small sample size and inconsistent application methods. Therefore, larger trials and standardized methodology are needed to reach more stronger and exact results.

• Genomics & Informatics
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• v.19 no.1
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• pp.9.1-9.5
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• 2021

Mammalian olfactory receptors are a family of G protein-coupled receptors (GPCRs) that occupy a large part of the genome. In human genes, olfactory receptors account for more than 40% of all GPCRs. Several types of GPCR structures have been identified, but there is no single olfactory receptor whose structure has been determined experimentally to date. The aim of this study was to model the interactions between an olfactory receptor and its ligands at the molecular level to provide hints on the binding modes between the OR2W1 olfactory receptor and its agonists and inverse agonists. The results demonstrated the modes of ligand binding in a three-dimensional model of OR2W1 and showed a statistically significant difference in binding affinity to the olfactory receptor between agonists and inverse agonists.

• Journal of Korean Neurosurgical Society
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• v.58 no.2
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• pp.107-111
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• 2015

Objective : Patients treated with surgical clipping for anterior communicating artery (A-com) aneurysm often complain of anosmia, which can markedly impede their quality of life. We introduce a simple and useful technique to reduce postoperative olfactory dysfunction in A-com aneurysm surgery. Methods : We retrospectively reviewed the medical records of patients who underwent surgical clipping for unruptured aneurysm from 2011-2013 by the same senior attending physician. Since March 2012, olfactory protection using gelfoam and fibrin glue was applied in A-com aneurysm surgery. Therefore we categorized patients in two groups from this time-protected group and unprotected group. Results : Of the 63 enrolled patients, 16 patients showed postoperative olfactory dysfunction-including 8 anosmia patients (protected group : unprotected group=1 : 7) and 8 hyposmia patients (protected group : unprotected group=2 : 6). Thirty five patients who received olfactory protection during surgery showed a lower rate of anosmia (p=0.037, OR 10.516, 95% CI 1.159-95.449) and olfactory dysfunction (p=0.003, OR 8.693, 95% CI 2.138-35.356). Superior direction of the aneurysm was also associated with a risk of olfactory dysfunction (p=0.015, OR 5.535, 95% CI 1.390-22.039). Conclusion : Superior direction of aneurysm appears associated with postoperative olfactory dysfunction. Olfactory protection using gelfoam and fibrin glue could be a simple, safe, and useful method to preserve olfactory function during A-com aneurysm surgery.