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At least 667 records · Page 37Linked to original sources
PubMed2005

Preserving olfactory function in anterior craniofacial surgery through cribriform plate osteotomy applied in selected patients.

OBJECTIVE: Olfaction is often sacrificed to gain access to the cranial base in anterior craniofacial surgery. We describe the long-term results of olfactory function in patients who underwent anterior craniofacial surgery and a cribriform plate osteotomy to preserve olfaction. METHODS: Between 1992 and 2004, 28 patients underwent 29 cribriform plate osteotomies in an attempt to preserve olfaction during anterior craniofacial surgery performed through modified extended transbasal approaches. Patients' charts and office notes were reviewed retrospectively. Formal olfactory testing was available in 5 patients, but most data were based on patients' subjective reports of olfaction. Olfactory preservation was defined by the subjective ability to detect fumes such as coffee, chocolate, roses, and orange juice regardless of the intensity of the sensation. Follow-up was based on phone calls to patients. RESULTS: Four patients were lost to follow-up and excluded. Therefore, follow-up was available in 24 patients after 25 procedures. On the basis of patients' subjective reports, olfaction was spared in 22 patients after 23 procedures (92%) and was confirmed objectively in the five patients formally tested. After surgery, only two patients were anosmic. CONCLUSION: Olfaction can be preserved in selected patients undergoing anterior craniofacial surgery. At least 1 cm of nasal mucosa should remain attached to the cribriform plate, which can be achieved by including the nasal bone in the osteotomy of the orbital bar. A medial orbital canthopexy is therefore necessary after these procedures.

Adolescent↗
PubMed1995

[Disorders of the sense of smell and taste].

Disorders of olfaction and taste are infrequent, but a complete loss of smell or taste reduces the quality of life significantly. The sensitivity of human olfaction is remarkable, even for specific stimuli: Just a few molecules are enough to induce the correct identification of sterilised and ultraheated milk. Olfaction and taste are called 'chemical senses' because in both cases the adequate stimulus consists of molecules that bind to receptors of the sensory cells. The perceptions of smell and taste are often combined. Taste differentiates only four qualities: sweet, sour, salty, and bitter. The typical flavor of food or drink is detected by olfaction. Disturbances of olfaction can be due to respiratory disorders such as nasal polyps, a deviation of the nasal septum or chronic sinusitis. Such conditions can reduce airflow through the olfactory cleft at the roof of the nasal cavity. They can be corrected by modern endoscopic surgery of the nose. Epithelial disorders involving the sensory cells are most often caused by viral infections (influenza-anosmia) or toxic destruction of the sensory epithelium (solvents or gases). Epithelial disorders can be cured only rarely by any treatment. Corticosteroids, zinc, and vitamin A are tried frequently. Neural disorders occur after frontobasal trauma and during neurological diseases such as Parkinson's or Alzheimer's disease. Disorders of olfaction can be an early sign of such neurological diseases and sophisticated examination of this sense can contribute to their early diagnosis. However, no specific treatments have yet been identified. Disorders of taste can be due to toxic, chemical or inflammatory damage to the sensory cells of the tongue.(ABSTRACT TRUNCATED AT 250 WORDS)

Central Nervous System Diseases↗
PubMed2003

[Factors that affect the improvement of olfactory function after endoscopic sinus surgery in patients suffering from chronic sinusitis and/or nasal polyps].

OBJECTIVE: To investigate the factors related to the improvement of olfaction after endoscopic sinus surgery (ESS) in chronic sinusitis and/or nasal polyps patients. METHOD: Fourteen patients suffering from chronic sinusitis and/or nasal polyps were accompanied with olfactory dysfunction. At 6 months after the ESS, measurement of olfaction showed that 27 patients' olfaction had improved. The effective rate is 61.36%. Using a logistic regression model, we analyzed the factors such as gender, disease stage, disease site, allergy, duration of olfactory dysfunction and follow-up. RESULT: Contrary to gender, disease site and duration of olfactory dysfunction, disease stage, allergy and follow-up had a significant effect on the improvement of olfaction. CONCLUSION: In order to improve the olfaction of the patients with chronic sinusitis and/or nasal polyps, it is important to treat positively with allergic rhinitis on a basis of the ESS. Follow-up should be emphasized further.

Adult↗
PubMed2005

Differences between orthonasal and retronasal olfactory functions in patients with loss of the sense of smell.

OBJECTIVE: To investigate differences between orthonasal and retronasal olfaction in patients with loss of the sense of smell without taste complaints. DESIGN: Electrophysiological and psychophysical testing of orthonasal and retronasal olfactory functions. SETTING: Outpatient clinics. PATIENTS: A series of 18 patients who had olfactory loss due to various reasons but no "taste" complaints. MAIN OUTCOME MEASURES: Orthonasal and retronasal olfactory functions assessed by olfactory event-related potentials and psychophysical smell tests. RESULTS: Psychophysical testing revealed retronasal olfaction to be normal or slightly altered, whereas orthonasal olfaction was either absent or severely compromised. Findings from nasal endoscopic examinations and computed tomographic scans were within the reference range in all subjects. In response to orthonasal stimulation there were neither detectable olfactory event-related potentials nor any with small amplitudes, whereas olfactory event-related potentials in response to retronasal stimulation were clearly present in some patients. CONCLUSION: These clinical observations, together with the psychophysical and electrophysiological findings, suggest that orthonasal and retronasal olfaction might be processed differently.

Adult↗
PubMed1995

Olfactory function in atypical parkinsonian syndromes.

INTRODUCTION: Olfaction is markedly impaired in patients with idiopathic Parkinson's disease (IPD). This deficit contrasts with reports of preserved or only mildly reduced olfaction in patients with atypical parkinsonism. However, the sensitivity and specificity of olfactory function testing in the differential diagnosis of parkinsonian syndromes has not been studied. In addition, olfactory function in patients with corticobasal degeneration (CBD) is unknown. MATERIAL AND METHODS: Using the University of Pennsylvania Smell Identification Test (UPSIT) with a test score ranging from 0 to 40 we studied olfactory function in patients with IPD as well as other parkinsonian syndromes including CBD and progressive supranuclear palsy (PSP). RESULTS: UPSIT scores in 118 patients with IPD, 29 with MSA, 15 with PSP, and 7 patients with CBD, as well as in 123 healthy control subjects revealed a marked impairment in the IPD group in contrast to mild impairment in MSA patients and normal olfaction in PSP and CBD patients. An UPSIT score of 25/40 was associated with a sensitivity of 77% and a specificity of 85% in differentiating IPD from atypical parkinsonism. CONCLUSIONS: These results indicate that olfactory function is differentially impaired or preserved in distinct parkinsonian syndromes and that it might also have some value as a diagnostic pointer. Thus, preserved or mildly impaired olfactory function in a parkinsonian patient is more likely to be related to atypical parkinsonism such as MSA, PSP or CBD, whereas markedly reduced olfaction is more suggestive of IPD.

Adult↗
PubMed1981

Preservation of the olfactory tract in bifrontal craniotomy for anterior communicating artery aneurysms, and the functional prognosis.

Results of surgical treatment of anterior communicating artery aneurysms, approached via bifrontal craniotomy, are reported in 110 cases. It was possible to preserve the olfactory tracts bilaterally or unilaterally in over 65% of these cases: 47% with bilateral preservation and 34% with unilateral preservation; 33% of the patients with bilateral olfactory tract damage reported subjectively normal olfactory. Objective examination of olfaction by an otolaryngologist showed that 84% of the patients reporting normal olfaction did indeed have normal olfaction, whereas 91% of these reporting no olfaction were anosmic.

Adolescent↗
PubMed2003

Central and peripheral circadian oscillators in Drosophila.

Drosophila circadian oscillators comprise interlocked period (per)/timeless (tim) and Clock (Clk) transcriptional/translational feedback loops. Within these feedback loops, CLOCK (CLK) and CYCLE (CYC) bind E-box elements to activate per and tim transcription, and we now show that at the same time CLK-CYC repress Clk by activating the transcriptional repressor vrille (vri), thus accounting for the opposite cycling phases of these transcripts and identifying vri as the negative component of the Clk-feedback-loop. The core oscillator mechanism is assumed to be the same for oscillators in different tissues. However, we have shown that CRYPTOCHROME (CRY) has a light-independent function in the oscillator that controls olfaction rhythms, suggesting that CRY may function within the oscillator mechanism itself as it does in mammals. These olfaction rhythms require the function of 'peripheral' oscillators which are distinct from the 'central' lateral neuron (LN) oscillators that mediate locomotor activity rhythms. Preliminary results show that antennal oscillator cells are sufficient and LNs are not necessary for olfaction rhythms, indicating that unlike the situation in mammals, the central oscillator has little impact on the olfaction rhythm oscillator under these conditions.

Animals↗
PubMed2004

The olfactory experience: constants and cultural variables.

Odor and olfaction anthropology explores four lines of research which, in many cases, may overlap: the variability of the olfactory perception, olfactory skills and know-how, odor use, and odor representations. My proposal here is to deal with the first one, trying to answer the following question: is olfactory perception a phenomenon resulting solely from the biological organization of the human being, in such a way that it does not know other variations than the ones due to nature? Or, on the contrary, can we show different kinds of olfaction culturally determined or, at least, environmental influences resulting in significant perceptual differences among groups, societies, cultures, etc.? In the first part of the text, I will deal with the invariants (or universals). In the second, I will insist on the cultural types of olfaction. In the third and last part, I will advance the following proposal: beyond the discussion on the roles that nature and culture play in human olfaction, we can sustain that naturally and culturally, there is a way of smelling characteristic of our species. Finally, I will conclude with two examples of the symbolic treatment characteristic of the olfactory human experience.

Cultural Characteristics↗
PubMed2005

[Olfactory dysfunction due to nasal sinus disease. Causes, consequences, epidemiology, and therapy].

Olfaction not only contributes to our quality of life but, among other functions, it is also necessary for identifying potential dangers, e.g., fire or spoilt food. In general the value of olfaction is only recognized when the sense of smell is impaired or lost. Olfactory dysfunction is diagnosed according to its cause (e.g., sinonasal, post-traumatic, post-upper respiratory tract infection, neurodegenerative, and idiopathic). At present little is known about prognostic factors for predicting resolution of olfactory loss on an individual basis. In cases of impaired olfaction due to sinonasal disease, both conservative and operative treatments have been established. Corticoids are used both topically and systemically. In cases of severe mechanical obstructions or advanced stages of nasal polyposis, FESS (functional endoscopic sinus surgery) seems to be the state of the art.

Causality↗
PubMed2000

[Dependence of uni- and bilateral olfactory capacity on nasal airflow in patients with chronic rhinosinusitis].

OBJECTIVE: Olfactory dysfunction is a common finding in patients with chronic rhinosinusitis (CRS). The aim of this study was to investigate the relationship between olfaction and nasal flow as determined by active anterior rhinomanometry (AAR). METHODS: Thirty patients with CRS were included in this series. Patients' histories and subjective assessments of olfaction were documented with questionnaires. Smell tests, assessments of olfaction, AAR, and results of rhinoscopy were recorded, including odor identification, discrimination and thresholds measured with the "Sniffin' Sticks"-test. RESULTS: CRS influenced olfactory performances variably in the different tests: 10% of the patients had pathologic rates of odor discrimination, compared with 34% in odor identification and 73% in thresholds. Statistical analyses (using Spearman's test) indicated a significant correlation between nasal airflow and odor identification screening (r29 = 0.56, P < 0.01) and n-butanol-threshold (r29 = 0.44, P < 0.05), respectively. CONCLUSION: Olfactory performance in CRS was correlated to several parameters of nasal airflow measured with AAR. The n-butanol threshold test revealed the most frequent pathological results and may best be used for detecting olfactory disorders. However, because a number of factors may influence olfactory dysfunction in CRS, our findings must be evaluated in a lager series.

Adolescent↗
PubMed2004

Olfactory impairment in monozygotic twins discordant for schizophrenia.

OBJECTIVE: Several studies demonstrated olfactory dysfunction in patients with schizophrenia, some reported deficient olfaction in unaffected relatives of schizophrenics as well. This study differentially assessed olfactory acuity as well as smell identification and smell discrimination in monozygotic twins discordant for schizophrenia and healthy, monozygotic control twins, to determine the genetic basis of different olfactory modalities and their association to schizophrenia. METHOD: The Sniffin'Sticks test,a comprehensive and standardized olfactory test, was employed to assess the olfactory function of 10 monozygotic twin pairs discordant for schizophrenia versus 10 age- and sexmatched healthy,monozygotic twin pairs. RESULTS: Olfaction of affected monozygotic twins was globally impaired. Partial olfactory impairment of their unaffected co-twins may point to a genetic cause of olfactory impairment in schizophrenia. The influence of genetic factors was most evident for olfactory acuity and least evident for smell identification. All olfactory functions declined with duration of illness. Side of stimulus presentation did not influence olfactory performance. CONCLUSIONS: Genetic factors associated with olfactory dysfunction may contribute to schizophrenia. The degree of the genetic influence on olfaction depends on the olfactory domain under examination.

Adult↗
PubMed1982

Olfactory dysfunction in man: anatomical and behavioral aspects.

We reviewed studies examining the olfaction of patients with brain damage for the purpose of discerning correlations between disordered structure and function. Patient samples included those with neurological disorders and neurosurgical interventions and recording of spontaneous or elicited neuronal activity. Brain areas involved in olfaction include the olfactory bulbs, the orbitofrontal and medial temporal cortices, the thalamus, and the amygdala. Despite recent advances in olfactory anatomy, understanding of how these structures are related to olfactory detection, discrimination, and recognition continues to be limited. Inadequate localization of brain lesions and lack of comprehensive behavioral assessment have thus far prevented a detailed account of the organization of olfaction in the human brain.

Alcohol Amnestic Disorder↗
PubMed2005

Odor perception in patients with mood disorders.

BACKGROUND: Olfaction has obvious correlates with emotional processes but little is known about the several aspects of olfaction in psychiatric disorders characterized by mood disturbance. This research aims at pointing out the specificities of olfactory perception in patients in order to identify the specific cerebral impairments involved in these disorders. METHODS: Olfactory sensitivity, detection, identification, self-evaluation of intensity and pleasantness have been recorded in a control group of healthy subjects (N = 58) and in three sample populations admitted to a Psychiatry Department: depressive patients (N = 49), anorectic patients (N = 17), and patients suffering from addiction to alcohol or drugs (N = 21). RESULTS: Depressive patients have a poor sensitivity, poor detection abilities but over-evaluate the pleasantness of odors. Anorectic patients have a high sensitivity, over-evaluate the intensities of the odors but under-evaluate their pleasantness. Alcoholic/drug addicted patients showed impairments in identification. LIMITATION: This study does not identify inter-individual differences in olfactory perception. CONCLUSION: The psychiatric diseases, here at hand although every one of them may be characterized by depressive components, show diverging impairments in olfactory perception. When variations in sensitivity are usually attributed to peripheral cues, impairments in emotional and cognitive aspects of olfaction are typically related to specific brain structures and processes which could be particularly involved in these diseases.

Adolescent↗
PubMed2006

Mucociliary clearance and sense of smell following management of Le Fort maxilla fractures.

OBJECTIVE: To assess mucociliary transport and olfaction in patients after Le Fort fractures. STUDY DESIGN: Forty-one patients were enrolled who had sustained a Le Fort fracture during the preceding five years. Control group consisted of students. Olfaction and mucociliary transport were examined in all subjects. A capillary with saccharine was placed on the inferior nasal concha, and time was recorded in which the subject tasted sweetness in the mouth. Results were subject to statistical analysis. Patients with allergy, sinus disease and smokers were excluded from the examination. RESULTS: Disturbance of mucociliary transport and olfaction turned out to be statistically dependent on the type of fracture and management. CONCLUSIONS: Le Fort fracture might be complicated by compromised mucociliary clearance and olfactory disturbances.

Adult↗
PubMed2002

Odor identification, eye tracking and deficit syndrome schizophrenia.

BACKGROUND: Deficit syndrome (DS) schizophrenia patients have smooth pursuit eye movement (SPEM) dysfunction. We examined if they also had smell identification deficits, since social affiliation is related to olfaction in other mammals. METHODS: Sixty-seven patients had DS assessments: 31 patients had SPEM and 50 had Smell Identification Test (SIT) assessments, and 14 patients had both measurements. RESULTS: DS patients had worse SPEM and SIT performance than the non-DS patients. Areas under the receiver-operator characteristic (ROC) curves for SIT and SPEM were both fairly accurate in identifying the DS. The odds ratio (OR) for the DS for impaired versus normal SPEM was 6.21 (95% confidence interval [CI]: 1.21, 32.25) and for microsmia versus normosmia was 10.4 (95% CI: 1.23, 88.18). Further analyses showed that the association of SIT with both SPEM and the DS could account for the SPEM-DS association. CONCLUSIONS: We found a strong association between the DS and SIT scores suggesting that the neural substrates of olfaction may be related to social affiliation in humans, as they are in other mammals. These data further support the notion that the DS defines a homogeneous subgroup of schizophrenia patients and further suggest that dysfunction in the neural circuitry of olfaction may contribute to its pathophysiology.

Adult↗
PubMed2000

Disruption of the type III adenylyl cyclase gene leads to peripheral and behavioral anosmia in transgenic mice.

Cyclic nucleotide-gated ion channels in olfactory sensory neurons (OSNs) are hypothesized to play a critical role in olfaction. However, it has not been demonstrated that the cAMP signaling is required for olfactory-based behavioral responses, and the contributions of specific adenylyl cyclases to olfaction have not been defined. Here, we report the presence of adenylyl cyclases 2, 3, and 4 in olfactory cilia. To evaluate the role of AC3 in olfactory responses, we disrupted the gene for AC3 in mice. Interestingly, electroolfactogram (EOG) responses stimulated by either cAMP- or inositol 1,4,5-triphosphate- (IP3-) inducing odorants were completely ablated in AC3 mutants, despite the presence of AC2 and AC4 in olfactory cilia. Furthermore, AC3 mutants failed several olfaction-based behavioral tests, indicating that AC3 and cAMP signaling are critical for olfactory-dependent behavior.

Adenylyl Cyclases↗
PubMed1999

[Special characteristics of expert assessment of olfactory and taste disorders].

BACKGROUND: The number of medical expert opinions dealing with smell and taste disorders has continuously increased in recent years. However, an overview of the specific problems and results of those expert opinions has not been published until now. INDIVIDUALS AND METHODS: Olfaction was assessed by multiple subjective tests in 145 individuals with chemosensory dysfunction caused by trauma or occupational and environmental exposures. Additionally, a gustatory test, nasal endoscopy, anterior rhinomanometry, and radiography of the paranasal sinuses were performed. Malignering was diagnosed on a trial of multiple symptoms. Retronasal olfaction was tested using the Güttich gustatory olfaction test. RESULTS: Most of the medical expert opinions have been ordered by professional associations (42%) and insurance companies (28%). Compensation for olfactory dysfunction was claimed after trauma (64%), occupational exposure (23%) rhinosurgical procedures (8%), and laryngectomy (5%). Anosmia or hyposmia was claimed by 66% and 24% of all individuals, respectively. According to the results of the chemosensory tests, 41% of patients suffered from anosmia and 40% had hyposmia. Malignering was registered in 14%. CONCLUSIONS: The study shows that the "characteristic case" is a male in the late fourties, complaining of anosmia initially noticed after an occipital or frontobasal head trauma. The assessment of olfactory deficits related to toxic or chemical occupational exposure is difficult when a latency between the occupational exposure and the onset of chemosensory dysfunction is present. Moreover, interactions between the occupational exposure and nicotine or alcohol abuse must be taken into consideration. Claims for medical liability arose in 3% of the study group after septoplasty and sinus surgery.

Adolescent↗
PubMedDate not supplied

Functional MRI of congenital hyposmia: brain activation to odors and imagination of odors and tastes.

PURPOSE: Our goal was to use functional MRI (fMRI) to define brain activation in response to odors and imagination ("memory") of odors and tastes in patients who never recognized odors (congenital hyposmia). METHOD: Functional MR brain scans were obtained in nine patients with congenital hyposmia using multislice echo planar imaging (EPI) in response to odors of amyl acetate, menthone, and pyridine and to imagination ("memory") of banana and peppermint odors and to salt and sweet tastes. Functional MR brain scans were compared with those in normal subjects and patients with acquired hyposmia. Activation images were derived using correlation analysis, and ratios of areas of brain activated to total and hemispheric brain areas were calculated. Total and hemispheric activated pixel counts were used to quantitate regional brain activation. RESULTS: Brain activation in response to odors was present in patients with congenital hyposmia. Activation was significantly lower than in normal subjects and patients with acquired hyposmia and did not demonstrate differential vapor pressure-dependent detection responsiveness or odor response lateralization. Regional activation localization was in anterior frontal and temporal cortex similar to that in normal subjects and patients with acquired hyposmia. Activation in response to presented odors was diverse, with a larger group exhibiting little or no activation with localization only in anterior frontal and temporal cortex and a smaller group exhibiting greater activation with localization extending to more complex olfactory integration sites. "Memory" of odors and tastes elicited activation in the same central nervous system (CNS) regions in which activation in response to presented odors occurred, but responses were significantly lower than in normal subjects and patients with acquired hyposmia and did not lateralize. CONCLUSION: Odors induced CNS activation in patients with congenital hyposmia, which distinguishes olfaction from vision and audition since neither light nor acoustic stimuli induce CNS activation. Odor activation localized to anterior frontal and temporal cortex, consistent with the hypothesis that olfactory pathways are hard-wired into the CNS and that further pathways are undeveloped with primary olfactory system CNS connections but lack of secondary connections. However, some patients exhibited greater odor activation with response localization extending to cingulate and opercular cortex, indicating some olfactory signals impinge on and maintain secondary connections consistent with similar functions in vision and audition. Activation localization of taste "memory" to anterior frontal and temporal cortex is consistent with CNS plasticity and cross-modal CNS reorganization as described for vision and audition. Thus, there are differences and similarities between olfaction, vision, and audition, the differences dependent on unique qualities of olfaction, perhaps due to its diffuse, primitive, fundamental role in survival. Response heterogeneity to odors may reflect heterogeneous genetic abnormalities, independent of anatomic or hormonal changes but dependent on molecular abnormalities in growth factor function interfering with growth factor/stem cell interactions. Patients with congenital hyposmia offer an unique model system not previously explored in which congenital smell lack as measured by fMRI is reflective of congenital dysfunction of a major sensory system.

Adult↗