Development of a new psychophysical method to assess intranasal trigeminal chemosensory function.

BACKGROUND: The aim of this study was to develop a new psychophysical test to assess intranasal trigeminal chemosensory function. METHODOLOGY: The test is similar to the Sniffin’ Sticks test, but using pens impregnated with substances preferentially activating trigeminal afferents. Our test comprises detection threshold, discrimination, identification and lateralization tasks. In a first study, we evaluated healthy controls. In a second study, we evaluated the potential usefulness of this test in patients with rhinological conditions. RESULTS: Study 1: 86 controls were included. Threshold, identification and lateralization performance decreased with age. Test-retest reliability was similar to that of olfactory tests. Study 2: results of the controls group were compared to those of 59 patients (14 allergic rhinitis, 11 chronic rhinosinusitis with nasal polyps (CRSwNP), 9 without nasal polyps (CRSsNP), and 25 with an olfactory disorder (OD)). Controls had 1) lower detection thresholds compared to CRSwNP, CRSsNP and OD, 2) better discrimination and identification scores compared to OD, and 3) better lateralization scores compared to CRSwNP and CRSsNP. CONCLUSIONS: Our test allows to identify age-related changes in trigeminal chemosensory function. Trigeminal function seems to be differently affected in different pathologies. Further studies are necessary to validate our results and evaluate the impact of olfactory co-activation on the observed results.

Position paper on olfactory dysfunction.

BACKGROUND: Olfactory dysfunction is an increasingly recognised condition, associated with reduced quality of life and major health outcomes such as neurodegeneration and death. However, translational research in this field is limited by heterogeneity in methodological approach, including definitions of impairment, improvement and appropriate assessment techniques. Accordingly, effective treatments for smell loss are limited. In an effort to encourage high quality and comparable work in this field, among others, we propose the following ideas and recommendations. Whilst the full set of recommendations are outlined in the main document, points include the following: - Patients with suspected olfactory loss should undergo a full examination of the head and neck, including rigid nasal endoscopy with small diameter endoscopes. - Subjective olfactory assessment should not be undertaken in isolation, given its poor reliability. - Psychophysical assessment tools used in clinical and research settings should include reliable and validated tests of odour threshold, and/or one of odour identification or discrimination. - Comprehensive chemosensory assessment should include gustatory screening. - Smell training can be helpful in patients with olfactory loss of several aetiologies. CONCLUSIONS: We hope the current manuscript will encourage clinicians and researchers to adopt a common language, and in so doing, increase the methodological quality, consistency and generalisability of work in this field.

Local allergic rhinitis - a narrative review.

This narrative review aims to provide an up-to-date definition of local allergic rhinitis (LAR), its classification, mechanisms, comorbidities, recommendations for diagnosis and treatment, and define needs in this area. Both 'PubMed' and 'Science Direct' literature was reviewed systematically, and a manual search for studies not previously encountered in the databases was also carried out. Published studies were identified in PubMed covering the period from 1947 to 2022. The following keyword search strategy was used: (local allergic rhinitis* OR entopy* OR local Immunoglobulin E * OR nasal specific Immunoglobulin E). LAR involves Type 2 nasal inflammation with local IgE and cannot be diagnosed by systemic methods, such as skin prick or blood IgE tests. A nasal allergen challenge is necessary for diagnosis. LAR can respond to usual AR treatments, including allergen specific immunotherapy (AIT). LAR is a novel entity that requires additional investigation in terms of prevalence, proper diagnosis, treatment, and prognosis. The target outcomes and possible benefits of this review are to achieve a consensus for the study and diagnosis of LAR and increase interest in this area.

Downregulation of polymeric immunoglobulin receptor and secretory IgA antibodies in eosinophilic upper airway diseases.

BACKGROUND: Immunoglobulin (Ig) A represents a first-line defence mechanism in the airways, but little is known regarding its implication in upper airway disorders. This study aimed to address the hypothesis that polymeric Ig receptor (pIgR)-mediated secretory IgA immunity could be impaired in chronic upper airway diseases. METHODS: Nasal and ethmoidal biopsies, as well as nasal secretions, were collected from patients with chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) or without nasal polyps (CRSsNP), allergic rhinitis (AR) and controls, and assayed for IgA1/IgA2 synthesis, pIgR expression, production of secretory component (SC), IgA and relevant IgA antibodies, and correlated with local eosinophils and inflammatory features (IL-12, IL-13 and ECP). RESULTS: pIgR expression was decreased in the ethmoidal mucosa in patients with CRSwNP (P = 0.003) and in AR (P = 0.006). This pIgR defect was associated with reduced levels of SC (P = 0.007) and IgA antibodies to Staphylococcus aureus enterotoxin B (SAEB) (P = 0.003) in nasal secretions from patients with CRSwNP, and with increased IgA deposition in subepithelial areas. pIgR downregulation was selectively observed in patients with tissue eosinophilia, whilst no clear relation to smoking history was observed. CONCLUSION: Epithelial pIgR expression is decreased in patients with CRSwNP and AR and results in decreased SC and IgA antibodies to certain bacterial antigens (SAEB) in nasal secretions of patients with CRSwNP in parallel to subepithelial accumulation of IgA. This defect in mucosal immunity is associated with eosinophilic, Th2-related inflammation.

Cystic dilation of the distal end of the nasolacrimal duct: underrated cause of epiphora in adults and its endoscopic treatment.

Epiphora is a frequent reason for ophthalmologic consultation. Among the multiple causes, obstructions of the lacrimal excretory system are common. Sacal and postsacal obstructions are much more frequent than presacal obstructions. Obstruction at the level of the Hasner's valve is rare and likely underestimated. The authors report the clinical history and the imaging of 3 patients with a cystic dilation of the distal end of the nasolacrimal duct (NLD). These patients were easily managed by an ENT surgeon. In one case, the surgery consisted of an endonasal DCR where in the 2 other cases, a marsupialisation of the cystic expansion of the nasolacrimal duct was successfully performed with the micro- debrider. The authors review the world literature on this specific topic. They conclude that a coronal sinus CT scan and an inferior meatus endoscopy should be included in the ophthalmologic work-up performed in all cases of low obstruction of the lacrimal system. When there is a dilation of the distal end of the NLD the marsupialisation of the cystic expansion in the inferior meatus is the option of treatment instead of performing a DCR. ENTs must play a role in the assessment and treatment of low obstructions of the lacrimal excretory system.

Locked-in syndrome as an unusual complication of acute otitis media.

BACKGROUND: A 32-year-old woman developed altered consciousness two days after initial symptoms of acute otitis media, with purulent discharge from the right ear. She was quadriplegic, with spontaneous eye opening, mild neck stiffness, and lacking vestibular-ocular reflexes. METHODOLOGY: Upon admission, the patient was subjected to brain computed tomography (CT), magnetic resonance imaging (MRI), and lumbar puncture. RESULTS: CT was consistent with pansinusitis, right middle ear otitis, mastoiditis, and sphenoiditis. No brainstem lesion was evident; brain MRI demonstrated ischemic and secondary hemorrhagic lesions in the pons and cerebral peduncles. The dura mater in the petroclival space was intensely inflamed, and likely responsible for reduced basilar arterial blood flow. Lumbar puncture yielded clear cerebrospinal fluid; gram stain examination was negative and culture remained sterile. Streptococcus pneumoniae and Haemophilus influenzae were cultured from the purulent ear discharge. CONCLUSION: The final diagnosis was locked-in syndrome consecutive to inflammatory changes compressing the basilar artery.

Consequences of chronic inflammation in children on facial growth, growth, behavioural disorders and smell.

Adenotonsillar hypertrophy is a common paediatric/otolaryngological disorder that may be associated with secondary growth or facial growth impairment, sleep disturbances, neurocognitive deficits, or smell loss. Surgical removal of the hypertrophic tissue eliminates the mechanical obstacle of the airways and is therefore curative in most cases. The purpose of the present review is to outline the impact of adenotonsillar hypertrophy and adenotonsillectomy on growth, facial growth, sleep, behaviour and smell.

Physiology of the mouth and pharynx, Waldeyer's ring, taste and smell.

This paper reviews the contribution of the different parts of the oral cavity and the pharynx to the basic physiology of breathing, phonation, speech, swallowing, and of Waldeyer's ring to the functioning of the immune system. We discuss the development of taste and smell, as well as possibilities for chemosensory testing in children.

Functional consequences of chronic ENT inflammation on the development of hearing and communicative abilities.

Hearing processing and communication abilities development may be influenced by chronic inflammation of the airways in children, especially in case of otitis media and/or adenotonsillar hypertrophy. The present review summarizes the influence of adenotonsillar hypertrophy on speech abilities as well as the consequences of otitis media, with a particular focus on peripheral and central hearing, on the development of language, attention, and memory skills.

The intranasal trigeminal system: roles in rhinitis (allergic and non-allergic).

The aim of this paper is to review intranasal trigeminal system and associated reflexes. The literature survey was performed on PubMed, ProQuest Central database of Kirikkale University and Google Scholar. The intranasal trigeminal system and associated reflexes play an important role in humans in both health and disease, including in rhinitis of non-allergic and mixed type. The intranasal trigeminal nerve provides sensory perception to the lining of the nose, supplying information on how patent the nasal airway is and responding to various chemical signals. The reflexes known to exist within the intranasal trigeminal system are nasobronchial reflex, trigemino-cardiac reflex, nasogastric reflex, and nasal cycle. The intranasal trigeminal system and its reflexes play a vital role in normal human physiology. Alterations in how this system operates may underlie multiple forms of rhinitis and more research is needed to fully understand the mechanisms involved.

Chemosensory event-related potentials in early blind humans.

While the effects of early visual deprivation on auditory and tactile functions have been widely studied, little is known about olfactory function in early blind subjects. The present study investigated the potential effect of early blindness on the electrophysiological correlates of passive odour perception. Event-related potentials (ERPs) were recorded in eight early blind humans and eight sighted controls matched for age, sex and handedness during olfactory stimulation with 2-phenyl ethyl alcohol and trigeminal stimulation with CO2 Latencies, amplitudes and topographical distributions were analysed. As expected, the olfactory and trigeminal ERP components showed normal latencies, amplitudes and topography in both groups. Olfactory stimuli generated responses of smaller amplitude than those observed in response to trigeminal stimulation. In addition, ERP analyses did not reveal any major difference in electrocortical responses in occipital areas in early blind and sighted subjects. These results suggest that passive olfactory and trigeminal stimulation elicit the same electrophysiological responses in both groups, confirming that the neurophysiological correlates of the cross-modal compensatory mechanisms in early blind subjects do not appear during passive olfactory and trigeminal perception.

Genetic evidence for a role of IL33 in nasal polyposis.

BACKGROUND: Little is known about the genetic factors that contribute to nasal polyposis (NP). A genome-wide association study identified 10 single nucleotide polymorphisms (SNPs) associated with eosinophilia. As eosinophils play a key role in the pathogenesis of NP, we assessed if any of these SNPs contribute to genetic susceptibility of NP. METHODS: We recruited 284 patients with NP in four participating hospitals in Belgium and 427 healthy controls, and genotyped 10 SNPs affecting eosinophilia (rs1420101 in IL1RL1, rs12619285 in IKZF2, rs4431128 in GATA2, rs4143832 in IL5, rs3184504 in SH2B3, rs2416257 in WDR36, rs2269426 in MHC, rs9494145 in MYB, rs748065 in GFRA2, and rs3939286 in IL33) using MALDI-TOF. A two-stage design was used while correcting for multiple testing. RESULTS: First stage analysis, involving 150 NP patients and 250 controls, identified rs3939286 nearby IL33 as a susceptibility factor for NP. Per at-risk A-allele, rs3939286 increased the risk for NP with an odds ratio (OR) of 1.60 (95% CI = 1.16-2.22; P = 0.0041). Second stage replication analysis in another 123 NP patients and 165 controls confirmed this association (OR = 1.43; CI = 1.00-2.06; P = 0.046). The combined analysis of both stages revealed an OR of 1.53 (CI = 1.21-1.96; P = 0.00041). Given the association of IL33 with NP, we also investigated rs1420101 in IL1RL1, which is the receptor for IL33. Although rs1420101 itself failed to associate with NP, a combined risk assessment of rs3939286 and rs1420101 further increased the risk for NP. CONCLUSION: We provide unprecedented genetic evidence suggesting a role for the IL33 pathway in the pathogenesis of NP.

Increasing olfactory bulb volume due to treatment of chronic rhinosinusitis--a longitudinal study.

Differentiation of progenitor cells into neurons in the olfactory bulb depends on olfactory stimulation that can lead to an increase in olfactory bulb volume. In this study, we investigated whether the human olfactory bulb volume increases with increasing olfactory function due to treatment of chronic rhinosinusitis. Nineteen patients with chronic rhinosinusitis were investigated before and after treatment. For comparison, additional measurements were performed in 18 healthy volunteers. Volumetric measurements of the olfactory bulb were based on planimetric manual contouring of magnetic resonance scans. Olfactory function was evaluated separately for each nostril using tests for odour threshold, odour discrimination and odour identification. Measurements were performed on two occasions, 3 months apart. In healthy controls, the olfactory bulb volume did not change significantly between the two measurements. In contrast, the olfactory bulb volume in patients increased significantly from the initial 64.5 +/- 3.2 to 70.0 +/- 3.5 mm(3) on the left side (P = 0.02) and from 60.9 +/- 3.5 to 72.4 +/- 2.8 mm(3) on the right side (P < 0.001). The increase in olfactory bulb volume correlated significantly with an increase in odour thresholds (r = 0.60, P = 0.006, left side; r = 0.49, P = 0.03, right side), but not with changes in odour discrimination or odour identification. Results of this study support the idea that stimulation of olfactory receptor neurons impacts on the cell death in the olfactory bulb, not only in rodents but also in humans. To our knowledge, this is the first longitudinal study that describes an enlargement of the human olfactory bulb due to improvement of peripheral olfactory function.

My surgery of the nasal valve.

We discuss the physiopathology and relevant anatomy of the nasal valves--internal and external--paying particular attention to the dynamics of the airflows in this area. We describe and comment on methods for medical examination, anterior rhinoscopy, endoscopy and fibrescopy of the valve, as well as the causes and sites of nasal valve dysfunction. We propose a review of the various treatments, medical and surgical, with a special emphasis on nasal valve surgery. Surgical techniques commonly used by the authors in daily practice for nasal valvuloplasty (such as spreader grafts and Z-plasty of the nostrils) are discussed and illustrated in depth. Some one-year postoperative results are presented and discussed.

The use of grafting material in rhinoseptoplasty.

Grafting is one of the current range of instruments that rhinoplasticians deploy to achieve durable and desired aesthetic and functional outcomes. Grafts can be classified according to anatomical site and, in the vast majority of cases, they involve augmentation rhinoseptoplasty. Visible grafting material is used for aesthetic purposes and functional grafting may involve invisible grafts. This article reviews the more widely described and more common indications for grafts in rhinoseptoplasty. The authors' rhinoseptoplasty philosophy involves a preference for autogenous grafts rather than alloplastic implants to achieve both aesthetically and functionally favourable results, particularly in long-term follow-up. They also prefer grafts in an open approach, reserving graft insertion with an endonasal approach for selected cases. The rate of complications associated with grafting is very low. The aim of this paper is to discuss the relevant anatomy, functional purpose and terminology, and to describe the authors' philosophy for grafting in rhinoseptoplasty.

Adaptation of the Sniffin' Sticks Test in South-Kivu.

AIM: The "Sniffin' Sticks" test is widely used in Europe as a standard test to assess olfaction. Several culturally-adapted versions have been developed. However, no version adapted to Sub-Saharan African populations exists. The aims of the present study were (1) to assess the applicability of the Sniffin' Sticks test in the population of South Kivu (DR Congo), and (2) to develop a culturally adapted version with normative values. MATERIALS AND METHODS: In a first study, 157 volunteers were tested with the original Sniffin' Sticks test. Based on these results, we selected odors that were poorly recognized in the identification test and replaced them by culturally adapted odors. In a second study, we assessed the modified version of the Sniffin' Sticks test in 150 volunteers and defined normative values. RESULTS: In the first study, we found that olfactory function (threshold-discrimination-identification: TDI score) significantly decreased with age and was better in females. Five odors were poorly recognized and were replaced by culturally adapted odors. In the second study, we found that this adapted version led to a higher rate of correctly identified odors. We defined normative values for the South-Kivu population (TDI score: 18-35 years: 30.4±6.0; 36-55 years: 26.2±5.3; >55 years: 25.6±5.0). CONCLUSION: This culturally adapted version of the Sniffin' Sticks test is culturally adapted to the South Kivu population. The normative values will provide the basis for clinical evaluation of pathologic subjects.

Olfactory bulb volume in the clinical assessment of olfactory dysfunction.

The olfactory bulb collects the sensory afferents of the olfactory receptor cells located in the olfactory neuroepithelium. The olfactory bulb ends with the olfactory tract and is closely related to the olfactory sulcus of the frontal lobe. Many studies demonstrated that olfactory bulb volume assessed with magnetic resonance imaging is related to the olfactory function both in normal and pathological conditions. It has been shown that olfactory bulb volume changes with the degree of olfactory dysfunction, that it decreases with the duration of the olfactory loss and that patients with qualitative disorder such as parosmia have smaller olfactory bulbs than patients without parosmia. In this review, we will discuss the actual knowledge regarding olfactory bulb function, practical ways to measure olfactory bulb volume and olfactory sulcus depth, and report systematic observations regarding these measurements related to various causes of olfactory dysfunction, e.g. infection of the upper respiratory tract, head trauma, or neurodegenerative disease. Measurement of olfactory bulb volume may provide valuable information for patients with olfactory dysfunction.

Usefulness and feasibility of psychophysical and electrophysiological olfactory testing in the rhinology clinic.

TOPIC: Olfactory dysfunction may be assessed in the clinic with psychophysical testing and electrophysiological recording. Chemosensory event-related potentials (CSERPs) constitute an objective method to assess chemosensory function. Olfactory and trigeminal stimuli activate chemoreceptors from the olfactory neuroepithelium and from the nasal mucosa to evoke an electrophysiological response respectively called olfactory (OERPs) and trigeminal ERPs (TERPs). The purpose of this study is to assess the usefulness and feasibility of these diagnostic tools in the rhinology clinic and to correlate these results to the olfactory disorder aetiology. MATERIALS AND METHODS: This study encompasses a cohort of 229 patients with a complaint of olfactory dysfunction from different origins. Orthonasal (Sniffing stick test with the treshold-discrimination-identification score: maximal score 48) and retronasal olfactory (maximal score 20) testing as well as CSERPs both after olfactory and trigeminal stimuli have been routinely performed. Olfactory dysfunction aetiologies were as follows: congenital (Cong.), chronic rhinosinusitis (CRS), idiopathic (Idiop.), post-medication (PM), neurologic (Neuro.), post-traumatic (PT) and post-infection (PI). RESULTS: Mean orthonasal and retronasal scores were respectively: 11.8 and 10.1 for Cong., 18.5 and 13.1 for CRS, 15.6 and 10.4 for Idiop., 15.3 and 10.2 for PM, 17 and 10.6 for Neuro., 15 and 9.9 for PT and 18.3 and 12 for PI. Correlations between orthonasal and retronasal scores were present for all subgroups except congenital and chronic rhinosinusitis subgroups. Orthonasal and retronasal scores were different (p < 0.05) when comparing CRS vs Cong., CRS vs PT and PT vs PI. Technical problems (olfactometer or olfactory stimulation, EEG amplifier,...) and patients discomfort (anxiety, stress,...) did not allow to draw any conclusion in 2 patients. Three patients after olfactory stimulus and 6 patients after trigeminal stimulus demonstrated too much eye blinking or muscular artifacts that did not allow us to perform electrophysiological analysis and averaging as 60% of artifact-free recording was not achieved. Olfactory ERPs were recorded in 28% of the patients and trigeminal ERPs were obtained in almost every patient (95%). There was no statistical difference between each subgroup regarding the presence or absence of OERPs. CONCLUSIONS: Psychophysical olfactory testing is a useful method to assess olfactory function in patients with olfactory loss and may help us to obtain a semi-objective and a basal evaluation of the olfactory performances. Feasibility and usefulness of CSERPs are also underlined in this study with only a limited number of patients who did not complete the examination. Psychophysical testing gives different results according to the aetiology of the olfactory disorder, which was not the case for electrophysiological recording. Olfactory acuity assessment should be based on psychophysical and CSERPs evaluation in a clinical setting.

Medical therapy and smell dysfunction.

Olfactory dysfunction is deemed to be a significant contributor to poor quality of life in different nasal inflammatory conditions like common cold, allergic rhinitis, and acute and chronic rhinosinusitis with and without nasal polyps (NP). The mechanism underlying olfactory impairment in inflammatory sinonasal disease relates to either the obstruction of the olfactory cleft due to congestion of the nasal mucosa, the presence of secretions or polyps inside the nasal cavity, or to dysfunction of the sensory mucosa of the olfactory bulb resulting from local inflammation. The reduction of smell capacity in nasal inflammatory conditions may have an acute or gradual onset, often with resolution of smell dysfunction after adequate medical treatment or surgery. In contrast to the well documented effects of surgery for rhinosinusitis on smell dysfunction, the available information about the effects of medical treatment is limited. Most studies have looked at corticosteroids, evaluating the restoration of olfactory capacity as a primary or secondary study outcome parameter. Both nasal and systemic corticosteroids have a beneficial effect on olfactory dysfunction, with systemic treatment being the most powerful. This review aims to provide an overview of current knowledge about medical treatment for rhinosinusitis and its effects on smell.

Chemosensory pathways: from periphery to cortex.

The aim of this article is to summarise the anatomy of the chemosensory pathways. The vomeronasal organ, the olfactory system, the trigeminal system and the gustatory system will be reviewed in succession. For each of these systems, we will provide a description of the anatomy of the pathways sending the sensory message from the peripheral receptor to the cortical areas, passing through different relays in the nervous system. Particular emphasis will be paid to the anatomical features of the structures involved in chemosensory perception. This will help us to understand better how these systems interact and influence our social lives, our memories and our behaviour, and to evaluate patients with chemosensory dysfunction better.