-
[show abstract]
[hide abstract]
ABSTRACT: Physiological investigation of olfactory receptor function in hyposmic or anosmic patients is rare. Pioneers examined the electro-olfactogram in patients with olfactory disturbance. Although the electro-olfactogram is an established method to record olfactory responses from human olfactory epithelium, the response is only measured at specific sites of the olfactory mucosa. In contrast to that the response of the olfactory epithelium to chemosensory stimuli can be studied in a specific nasal area by means of intrinsic optical signal recording. Five functionally anosmic patients were included in the present study. In all patients, responses could be obtained following trigeminal stimulation with CO(2). In some patients, responses could be obtained after olfactory stimulation with H(2)S and PEA. The present data show that in the studied patients trigeminal function seems to be preserved, while it appears that in some patients olfactory function is preserved to a certain degree.
Archives of Oto-Rhino-Laryngology 10/2012; · 1.29 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Recent research demonstrated that background noise relative to silence impaired subjects' performance in a cognitively driven odor discrimination test. The current study aimed to investigate whether the background noise can also modulate performance in an odor sensitivity task that is less cognitively loaded. Previous studies have shown that the effect of background noise on task performance can be different in relation to degree of extraversion and/or type of noise. Accordingly, we wanted to examine whether the influence of background noise on the odor sensitivity task can be altered as a function of the type of background noise (i.e., nonverbal vs. verbal noise) and the degree of extraversion (i.e., introvert vs. extrovert group). Subjects were asked to conduct an odor sensitivity task in the presence of either nonverbal noise (e.g., party sound) or verbal noise (e.g., audio book), or silence. Overall, the subjects' mean performance in the odor sensitivity task was not significantly different across three auditory conditions. However, with regard to the odor sensitivity task, a significant interaction emerged between the type of background noise and the degree of extraversion. Specifically, verbal noise relative to silence significantly impaired or improved the performance of the odor sensitivity task in the introvert or extrovert group, respectively; the differential effect of introversion/extraversion was not observed in the nonverbal noise-induced task performance. In conclusion, our findings provide new empirical evidence that type of background noise and degree of extraversion play an important role in modulating the effect of background noise on subjects' performance in an odor sensitivity task.
Experimental Brain Research 09/2012; 222(1-2):89-97. · 2.39 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In a subset of aspirin-tolerant asthmatics, administration of aspirin improves respiratory symptoms. We present a patient with chronic rhinosinusitis with nasal polyps who exhibited relief of nasal obstruction and nasal discharge and improvement in the sense of smell following oral administration of 150 mg of aspirin daily. Improvement in the patency of the nasal passages was documented by nasal endoscopy and magnetic resonance imaging. Improvement of olfactory function was documented by validated psychophysical olfactory testing and by means of olfactory event-related potentials.
Respiratory care 03/2012; 57(3):460-3. · 2.01 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Even though we often perceive odors in the presence of various background sounds, surprisingly little is known about the effects of background sound on odor perception. This study aimed to investigate the question whether background sound can modulate performance in an odor discrimination task. In Experiment 1, participants were asked to perform the odor discrimination task while listening to either background noise (e.g., verbal or non-verbal noise) or no additional sound (i.e., silent condition). Participants' performance in the odor discrimination task was significantly deteriorated in the presence of background noise compared with in the silent condition. Rather, the detrimental effect of verbal noise on the task performance was significantly higher than that of non-verbal noise. In Experiment 2, participants were asked to conduct the odor discrimination task while listening to either background music (Mozart's sonata for two pianos in D major, K448) or no additional sound (silent condition). Background music relative to silent condition did not significantly alter the task performance. In conclusion, our findings provide new empirical evidence that background sound modulates the performance in an odor discrimination task.
Experimental Brain Research 07/2011; 212(2):305-14. · 2.39 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: It is estimated that 15% of normosmic subjects demonstrate lateralized smell loss. The majority of individuals will not notice this difference between nostrils as long as olfactory function of the better nostril remains in the normal range. We were interested in the question whether subjects demonstrating clinically significant side differences of olfactory function are at risk to develop bilateral olfactory loss. Normosmic individuals with such side differences ("difference group", n = 35) were re-tested on average 4.6 years after baseline investigations. Additionally, 58 subjects who did not demonstrate side differences ("control group") were also re-investigated. All participants received detailed olfactory testing using the "Sniffin' Sticks" involving tests for odor threshold, odor discrimination, and odor identification. Olfactory testing at follow-up indicated lower olfactory function (p = 0.005) in the "difference group" than in the "control group". The degree of side difference at baseline correlated negatively with the results from olfactory testing at follow-up (r = -0.29; p = 0.01). These results suggest that individuals with side differences of olfactory function are at risk to develop bilateral olfactory loss within 4.5 years. Thus, the degree of lateralized smell function is an indicator for future smell loss.
Journal of Neurology 06/2010; 257(6):959-63. · 3.47 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In clinical settings, olfactory testing is usually performed bilaterally; thus, unilateral olfactory loss may go unnoticed. The aims of this study were to evaluate 1) whether patients presenting with self-reported olfactory disorders demonstrate significant side differences in odour perception, depending on the prevalance of measured unilateral disorder, and 2) to evaluate the existing testing procedure. In 518 patients presenting with olfactory disorders, olfactory testing was performed using the "Sniffin' Sticks" test battery (consisting of a threshold, discrimination, and odour identification test) examining each nostril separately. According to the history and results from the clinical examination, olfactory disorders were classified as related to trauma, sinunasal disease, upper respiratory tract infection (URTI), tumour, congenital, idiopathic, and other. A difference of three or more points in one of the subtests or six or more points in the composite olfactory test score was considered a side difference. In almost one quarter of all presenting patients (23.4%), a side difference was detected. To not to miss lateralized disorders, we recommend testing each nostril separately. Depending on the presence or absence of a significant difference, testing then can be continued birhinally or separately for each nostril.
Rhinology 06/2010; 48(2):156-9. · 1.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study investigates olfactory epithelium biopsies from patients with nasal polyposis, in correlation with olfactory test results and ratings of olfactory dysfunction pre- and postoperatively.
Twenty-seven patients with nasal polyposis were included. Olfactory function was tested with the "Sniffin Sticks" test. Biopsies from the olfactory region performed at the end of endoscopic surgery and studied with immunohistochemistry. Patients used a visual analogue scale to report their olfactory dysfunction when re-examined one year postoperatively.
Subjects with little or no inflammation in olfactory and respiratory biopsies had short-er duration of disease and better olfactory function. Pathological changes of olfactory mucosa included replacement by respiratory metaplasia, degenerated epithelium, rupture of epithelial surface and infiltration by inflammatory cells. Postoperative olfactory test results showed improvement of olfaction in 74% of patients. Although this improvement seemed to be better in subjects with little or no inflammation, this was not significant. Preoperative and postoperative olfactory test results were positively correlated.
The disease process includes loss of structural organization and inflammatory infiltration of the olfactory epithelium. The inflammation severity is related to the olfactory test results; however, it cannot be the only predictive factor postoperatively.
Rhinology 03/2010; 48(1):47-53. · 1.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The "Sniffin' Sticks" test kit is a validated and commonly used tool for assessment of olfactory function in subjects with normal sense of smell and in individuals with smell loss. That test incorporates subtests for odor threshold, discrimination, and identification. To gain higher subtest reproducibility, tests on odor discrimination and odor identification were extended using 32 instead of the usually applied 16 single trials each. In developing the extended Sniffin' Sticks test, a number of preliminary experiments were performed in 46 healthy, normosmic individuals 1) to evaluate intensity and familiarity of the additionally selected odors, 2) to select distractors for the discrimination and identification test, and 3) to evaluate the test-retest reliability of each subtest. Furthermore, the extended test was applied to 126 patients with olfactory loss and 71 normosmic individuals. Follow-up investigation could be performed in 69 controls within an average interval of 4 days. Results revealed significant differences between patients and healthy subjects. Estimated intensity and familiarity of the newly selected 16 items of the discrimination test did not differ significantly from the 16 standard items. Test-retest reliability was found to be r = 0.80 (odor discrimination), r = 0.88 (odor identification), and r = 0.92 (odor threshold). In conclusion, the extended test kit allows a precise evaluation of olfactory function, especially when different olfactory tasks are assessed using individual subtests. Furthermore, the high test-retest reliability of both the 16 and the 32-item tests allows the evaluation of even relatively small changes of olfactory function over time by means of either test.
Chemical Senses 10/2009; 34(8):705-11. · 2.60 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Options for the treatment of hyposmia are limited;available therapies do not provide a long-lasting effect.A recent study suggests that an unspecific phosphodiesterase inhibitor (PDE-I) increases olfactory sensitivity due to interaction with the signal transduction in the olfactory epithelium. The aim of the present study was to investigate whether theophylline, an unspecific PDE-I, evokes changes in the electro-olfactogram (EOG) which would support the hypothesis of a drug-related impact on signal transduction.In addition, the uptake of topically administered theophylline in the olfactory epithelium should be investigated. EOG was obtained in 29 samples of supravital mouse olfactory epithelia. Olfactory stimulation (phenylethyl alcohol, PEA and hydrogen sulfide, H2S) was performed using an air dilution olfactometer. Theophylline concentration in the olfactory epithelium of five samples was measured by means of high pressure liquid chromatography. Administration of theophylline resulted in a tendency towards smaller EOG amplitudes (p = 0.055), being reduced by 13 and 25% in response to stimulation with PEA or H2S,respectively. In comparison to the application of Ringer's solution, theophylline resulted in a significant (p = 0.031)decrease of the EOG amplitude. Latency was not significantly(p = 0.10) influenced by drug administration. The theophylline concentration in the olfactory epithelium ranged from 0.21 to 1.53 microg/mg. Theophylline seems to be taken up into the olfactory epithelium of supravital mice and to interact with the olfactory signal transduction.
Archives of Oto-Rhino-Laryngology 09/2009; 267(2):239-43. · 1.29 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Anecdotal reports from patients with smell loss provided the basic motivation for the present study on sexual dysfunction among patients with olfactory dysfunction. The aim of the present study was to investigate the sexual appetite and the subject's depression in regard to olfactory function.
Eighty-six patients referred to our smell and taste clinic with olfactory dysfunction were investigated. Olfactory function was assessed by means of the "Sniffin' Sticks" test battery consisting of tests for odor threshold (T), odor discrimination (D), and odor identification (I). Their results were summed up to a composite score, the so-called "TDI score." All participants completed a questionnaire including the Beck Depression Inventory (BDI) and 11 questions for evaluation of the sexual appetite in regard to the time before the onset of olfactory dysfunction and since the olfactory dysfunction. The points received for the latter questions were summed up to the so called Sexual Appetite Index (SAI).
Olfactory testing revealed that 38 patients were functionally anosmic, 39 patients were hyposmic, and nine patients were normosmic. The average BDI score was 11.0 +/- 8.4 points. Evaluation of the SAI questionnaire revealed a significant decrease (P = 0.003) of the score from 22.7 +/- 4.5 points from the time before to 21.4 +/- 4.9 points since the onset of olfactory loss. No significant correlation was found between olfactory function and the SAI since the onset of olfactory dysfunction. However, the BDI score correlated negatively with the SAI since the onset of olfactory dysfunction (r(85) = -0.36; P = 0.001).
The present study does not confirm the hypothesis that loss of olfactory function directly impacts on sexual appetite. It seems that depression caused by olfactory loss is the main cause for the self-reported decrease in sexual appetite as the onset of olfactory dysfunction.
Journal of Sexual Medicine 05/2009; 6(7):1924-9. · 3.55 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To investigate the effect of pentoxifylline, an unspecific phosphodiesterase inhibitor, on olfactory function.
Longitudinal study.
Nineteen patients who received pentoxifylline to treat inner-ear conditions.
Evaluation of olfactory function (ie, odor threshold, odor discrimination, and odor identification) before and after administration of pentoxifylline and assessment of nasal airflow.
Administration of pentoxifylline had no significant effect on nasal airflow (P = .84). After administration of pentoxifylline, patients demonstrated a decrease in odor threshold toward lower odor concentrations (P = .01). The odor threshold shift after administration of pentoxifylline was more pronounced in younger patients than in older patients (correlation between age and change in odor threshold: r = -.72; P = .001). No such changes were observed for suprathreshold olfactory tasks (odor discrimination and odor identification). Six of the 19 patients were found to have hyposmia. Two patients demonstrated a clinically significant decrease in odor threshold after drug administration.
The present findings may indicate a role for pentoxifylline in the treatment of olfactory loss. Double-blind, placebo-controlled studies are needed to verify whether pentoxifylline can improve olfactory sensitivity in patients with olfactory disorders.
Archives of otolaryngology--head & neck surgery 04/2009; 135(3):291-5. · 1.92 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Parkinson's disease (PD) is a neurodegenerative disorder involving several neuronal systems. Impaired olfactory function may constitute one of the earliest symptoms of PD. However, it is still unclear to what degree changes of the olfactory epithelium may contribute to dysosmia and if these changes are different from those of other hyposmic or anosmic patients. This study aimed to investigate the hypothesis that olfactory loss in PD is a consequence of specific PD-related damage of olfactory epithelium. Biopsies of 7 patients diagnosed with PD were taken. Six patients with PD were hyposmic, one anosmic. As non-PD controls served 9 patients with hyposmia, 9 with anosmia, and 7 normosmic individuals. Further, nasal mucosa of 4 postmortem individuals was investigated. Immunohistochemical examinations were performed with antibodies against olfactory marker protein (OMP), protein gene product 9.5 (PGP 9.5), beta-tubulin, (BT), proliferation-associated antigen (Ki 67), the stem cell marker nestin, cytokeratin, p75NGFr, and alpha-synuclein. Most of the biopsy specimens exhibited irregular areas of olfactory-like, dysplastic epithelium positive for either PGP 9.5 or BT, but negative for OMP. No major histochemical differences in either the expression or distribution of these proteins were observed in the olfactory epithelium of patients with PD compared with controls. Reverse transcription PCR (RT-PCR) data indicated mRNA for OMP in almost all subjects, independently of their olfactory performance. These data support the idea that olfactory loss in Parkinson's disease is not a consequence of damage to the olfactory epithelium but rather results from distinct central-nervous abnormalities.
Movement Disorders 03/2009; 24(6):906-14. · 4.51 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To investigate the impact of the use of more contrasted distractors on correct odor identification in patients with olfactory loss.
Randomized, cross-over study.
University clinic.
Thirty patients with olfactory deficits.
The olfactory function of the patients was evaluated by means of the "Sniffin' Sticks" test battery.
The distractors of the Sniffin' Sticks odor identification test (classic test) were modified, and more contrasted distractors were used (contrasted test), while the applied odorants were the same. All patients performed both the classic and the contrasted odor identification tests in a randomized sequence.
Eighteen patients were hyposmic, and 12 were functionally anosmic. Odor identification was significantly better in the hyposmic patients than in the anosmic patients (P < .01). As predicted, hyposmic patients demonstrated a significant increase in correct odor identification in the contrasted test, while anosmic patients did not.
The use of more contrasted distractors in cued odor identification tasks can contribute to better discrimination of anosmic and hyposmic patients, which is highly valuable in a clinical context.
Archives of otolaryngology--head & neck surgery 02/2009; 135(2):143-5. · 1.92 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Responses from the middle turbinate elicited by olfactory and trigeminal stimuli were studied using the intrinsic optical signal (IOS) recording technique. Nasal cavity was illuminated by 617 nm light. Olfactory (H2S) or trigeminal (CO2) stimuli of 5-s duration were presented using a computer-controlled olfactometer; IOS responses were captured by a special camera. Averages across five individual IOS recordings were analyzed. When the nasal cavity was exposed to H2S, a significant change of the IOS was found; responses to CO2 were even more pronounced. The present results argue for the idea that the IOS is an indicator of intranasal chemosensory activation.
Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 08/2008; 265(7):781-5. · 1.29 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The olfactory system and especially the olfactory bulb (OB) as the first relay in the olfactory system represent highly plastic structures. For example, OB volume partly reflects the degree of afferent neural activity. Research indicates that smell deficits leading to a reduced sensory input result in structural changes at the level of the OB. Reduced OB volumes also may be considered characteristic of parosmia. Apart from discussing the clinical implications of these findings, the radiologic basics for assessment of olfactory-eloquent structures are addressed in detail.
Neuroimaging Clinics of North America 06/2008; 18(2):233-42, preceding x. · 1.51 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Birhinal testing of odor identification will not allow the detection of unilateral olfactory loss. The aim of the presented study was to evaluate side differences of odor identification in large groups of healthy subjects and in patients with nasal symptoms.
Self-assessment of olfactory function and evaluation of olfactory function by means of a validated test were performed in 479 healthy subjects, in 765 patients with chronic rhinosinusitis (CRS), and in 53 patients with a tumor. A 12-item odor identification test ("Sniffin' Sticks") was used to evaluate olfactory function separately for each nostril.
Fifteen percent of the healthy subjects demonstrated side differences in the identification of at least 3 out of 12 odors. Healthy elderly subjects showed larger side differences in identification of odor than younger ones; a general difference between odor identification with the right or left nostril was not found. Both CRS patients and patients with a tumor had larger side differences than healthy subjects. Only 20% of the patients with a tumor complained about impaired olfactory sensitivity, but more than 75% of them showed deficits in olfactory tests.
Side differences of odor identification of 25% or greater should give reason for further investigation. Future studies are needed to investigate whether side differences in healthy subjects are a predicator of a higher risk for general olfactory loss.
The Laryngoscope 06/2007; 117(5):808-11. · 1.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Although widely used in healthy subjects and patients with olfactory loss, the significance of changes of scores from validated olfactory tests is unknown.
The aim of the present study was to relate the self-assigned changes of olfactory function in terms of "better," "unchanged," and "worse" in patients with smell disorders with the results from olfactory testing by means of a validated test set. Olfactory function of 83 anosmic or hyposmic patients (40 women, 43 men; age 12-84 yr) was tested on two occasions (mean interval 136 days, minimum 7 days, maximum 6.7 yr). Olfactory function was assessed using a validated technique ("Sniffin' Sticks"). This test consists of three subtests, one for odor threshold (T), odor discrimination (D), and odor identification (I), with possible results ranging up to 16 points each. From the sum of the results from the three subtests a composite "TDI" score was obtained.
Forty-four patients indicated an improvement of olfactory function, whereas 39 patients reported no change. No subject reported deterioration of olfactory sensitivity. Subjects assigned to group BETTER had higher TDI scores in the second olfactory tests than subjects assigned to the group UNCHANGED, both in absolute terms and as compared with the first olfactory test (effect "test occasion" by "self-assessed improvement," P < .001). There was no significant difference between groups with respect to age and sex (P = .99 and .84, respectively). Logistic regression showed that more than 60% of the subjects reported an improvement of olfactory sensitivity when the TDI score increased by 5.5 points.
We show that there is a statistically significant relation between measured and perceived improvement of olfactory function in patients who first presented with the diagnosis of anosmia or hyposmia. The results indicate that improved olfactory function in patients with olfactory deficiency is perceived as such in everyday life and is quantitatively related to an improvement in the composite TDI score of the "Sniffin' Sticks" olfactory test battery. This is the basis for the application of a specific therapy for olfactory loss because of a possible gain in quality of life for the patients.
The Laryngoscope 10/2006; 116(10):1858-63. · 1.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Background: Although widely used in healthy subjects and patients with olfactory loss, the significance of changes of scores from validated olfactory tests is unknown.Aim and Methods: The aim of the present study was to relate the self-assigned changes of olfactory function in terms of “better,” “unchanged,” and “worse” in patients with smell disorders with the results from olfactory testing by means of a validated test set. Olfactory function of 83 anosmic or hyposmic patients (40 women, 43 men; age 12–84 yr) was tested on two occasions (mean interval 136 days, minimum 7 days, maximum 6.7 yr). Olfactory function was assessed using a validated technique (“Sniffin' Sticks”). This test consists of three subtests, one for odor threshold (T), odor discrimination (D), and odor identification (I), with possible results ranging up to 16 points each. From the sum of the results from the three subtests a composite “TDI” score was obtained.Results: Forty-four patients indicated an improvement of olfactory function, whereas 39 patients reported no change. No subject reported deterioration of olfactory sensitivity. Subjects assigned to group BETTER had higher TDI scores in the second olfactory tests than subjects assigned to the group UNCHANGED, both in absolute terms and as compared with the first olfactory test (effect “test occasion” by “self-assessed improvement,” P < .001). There was no significant difference between groups with respect to age and sex (P = .99 and .84, respectively). Logistic regression showed that more than 60% of the subjects reported an improvement of olfactory sensitivity when the TDI score increased by 5.5 points.Conclusion: We show that there is a statistically significant relation between measured and perceived improvement of olfactory function in patients who first presented with the diagnosis of anosmia or hyposmia. The results indicate that improved olfactory function in patients with olfactory deficiency is perceived as such in everyday life and is quantitatively related to an improvement in the composite TDI score of the “Sniffin' Sticks” olfactory test battery. This is the basis for the application of a specific therapy for olfactory loss because of a possible gain in quality of life for the patients.
The Laryngoscope 09/2006; 116(10):1858 - 1863. · 1.75 Impact Factor