Olfactory cleft stenosis and obstruction on paranasal sinus CT scan in pre-septo-rhinoplasty patients: normal variants or pathologic findings?

OBJECTIVE(S)

To determine the frequency of olfactory cleft (OC) stenosis and obstruction on paranasal sinus CT scans in pre-septorhinoplasty of patients who had septal deviation, septopyramidal deformation or nasal obstruction without other sinonasal conditions.

METHODS

This retrospective study included patients referred to our institution between December 2013 and December 2021 for septorhinoplasty due to nasal obstruction without other sinonasal or neurological conditions. All patients underwent preoperative paranasal sinus CT scan and olfactory testing. OC stenosis was quoted as none, partial, or total (less than 1/3 contact between nasal septum and ethmoid turbinates, 1/3-2/3, more than 2/3, respectively), as well as OC obstruction as none, partial, or complete (obstruction of less than 1/3 of OC, 1/3-2/3, more than 2/3, respectively). Radiologic evaluation was validated by near perfect interobserver agreement.

RESULTS

A total of 75 patients (32 women, 43 men) with a mean age of 44.2 ± 15.64 (23-74) years were included, of which 36 were normosmic and 39 hyposmic. OC stenosis was partial in 58.7% (n = 44) of the patients, absent in 28% (n = 21), and total in 13.3% (n = 10), without difference between normosmic and hyposmic patients (p = .66). OC obstruction was absent in 52% (n = 39) and partial in 46.7% (n = 35), without difference between normosmic and hyposmic patients (p = .51). Only one normosmic patient had complete OC obstruction.

CONCLUSION

OC partial stenosis and partial obstruction were frequent findings in pre-septorhinoplasty patients without respiratory mucosa disease and did not influence their olfactory status. Total stenosis and complete obstruction were rarer and require further investigation.

CLINICAL RELEVANCE STATEMENT

Isolated partial olfactory cleft stenosis and obstruction should be considered normal variants, whereas the impact of complete olfactory cleft stenosis and obstruction on patient's olfactory status remains to be determined.

KEY POINTS

• The incidence of olfactory cleft stenosis and obstruction in asymptomatic patients remains unknown, even though it is encountered in clinical practice. • Partial and total olfactory cleft stenosis occurred in 58.7% and 13.3% of the patients; partial obstruction occurred in half of the cases, but complete obstruction was extremely rare. • There are frequent findings of partial olfactory cleft obstruction and stenosis, but complete obstruction and total stenosis should be further investigated.

Review of olfactory cleft roof anatomy

Progress in skull-base endoscopic surgery has improved our knowledge of olfactory cleft (OC) anatomy. This article presents a review of current knowledge concerning the OC roof: descriptive anatomy, radiological exploration, and endoscopic observation. The OC is a narrow area in the most superior part of the nasal cavity. Its roof is the thinnest structure separating the nasal cavities from the brain; it comprises three superimposed tissues: nasal mucosa, ethmoid cribriform plate (ECP), and dura mater. The ECP comprises the anterior ECP containing the ethmoidal slit (ES) medially and the cribroethmoidal foramen (CEF) laterally; and the posterior ECP, comprising the olfactory foramina. The OC roof is bordered anteriorly by the nasal bone roof, laterally by the lateral ethmoid masses, and posteriorly by the jugum and anterior wall of the sphenoid sinuses. Imaging is crucial for analyzing this wall, providing precise detailed information on conformation and anatomic relations with adjacent structures such as the anterior ethmoidal artery. Understanding OC roof anatomy and correct interpretation of imaging are essential for safety in present-day functional endoscopic sinus surgery and anterior skull-base oncologic surgery.

Olfactory cleft mass as the first presentation of asymptomatic metastatic renal cell carcinoma: A case report and review of the literature

INTRODUCTION AND IMPORTANCE

Renal cell carcinoma metastasis in the sinonasal cavities is rare. They account for less than 1 % of all metastases of these renal cancers.

CASE PRESENTATION

We report the case of a patient with an unremarkable pathological history, who consulted for recurrent right epistaxis. Nasal endoscopy revealed a reddish mass located medial to the right middle turbinate. Computed tomography and magnetic resonance imaging showed a lesion located at the level of the olfactory cleft. The patient had a complete removal of the mass and the anatomopathological examination concluded to a metastasis of a clear cell carcinoma of renal origin. Taking into account these results, a thoraco-abdomino-pelvic CT scan was performed and it discovered a left renal tumor.

CLINICAL DISCUSSION

The most frequent functional sign of Renal cell carcinoma metastases is epistaxis. This is explained by the rich vascularity of these metastases. The imaging data are not specific and do not allow differentiation between primary tumor and metastasis. The definitive diagnosis can be confirmed only by histologic examination.

CONCLUSION

Faced with any hypervascularized tumor of the nasal cavity, the ENT physician must evoke a metastasis of a renal cancer, even in the absence of history and symptoms evoking this cancer.

Preparation of Human Olfactory Epithelial Biopsies for Downstream Analysis

The olfactory mucosa, lining a portion of the nasal cavity, houses the primary olfactory sensory neurons responsible for odor transduction, along with supporting cell populations. Tremendous advances have come from studying the peripheral olfactory system in animal models, especially the mouse. However, acquired human olfactory disorders lack effective therapies, and many of these conditions involve pathology in the olfactory mucosa. Thus, the ability to obtain human olfactory biopsy samples from subjects with olfactory dysfunction, or controls, may be of value. Here, we describe established techniques for collecting olfactory tissue from human subjects and preparing samples for downstream assays such as immunohistochemistry, flow cytometry, single-cell RNA-sequencing, or chromatin studies.

Olfactory Cleft Length: A Possible Risk Factor for Persistent Post-COVID-19 Olfactory Dysfunction

INTRODUCTION

To date, little is known about predisposing factors for persistent COVID-19-induced olfactory dysfunction (pCIOD). The objective was to determine whether olfactory cleft (OC) measurements associate with pCIOD risk.

MATERIAL AND METHODS

Three subgroups were recruited: group A included patients with pCIOD, group B included patients without olfactory dysfunction following SARS-CoV-2 infection (ntCIOD), and group C consisted in controls without past history of SARS-CoV-2 infection (noCOVID-19). Olfactory perception threshold (OPT) and visual analog scale for olfactory impairment (VAS-olf) were obtained. OC measurements were obtained through computed tomography scans. Results were subsequently compared.

RESULTS

A total of 55 patients with a mean age of 39 ± 10 years were included. OPT was significantly lower in pCIOD patients (group A: 4.2 ± 2.1 vs. group B: 12.3 ± 1.8 and group C: 12.2 ± 1.5, p < 0.001). VAS-olf was significantly higher in pCIOD (group A: 6 ± 2.6 vs. group B: 1.7 ± 1.6 and group C: 1.6 ± 1.5, p < 0.001). OC length was significantly higher in group A (42.8 ± 4.6) compared to group B (39.7 ± 3.4, p = 0.047) and C (39.8 ± 4, p = 0.037). The odd of pCIOD occurring after COVID-19 infection increased by 21% (95% CI [0.981, 1.495]) for a one unit (mm) increase in OC length. The odd of pCIOD occurring was 6.9 times higher when OC length >40 mm.

CONCLUSION

Longer OC may be a predisposing factor for pCIOD. This study is expected to encourage further research on OC morphology and its impact on olfactory disorders.

Visualization of ex vivo rabbit olfactory mucosa and foramina with three-dimensional optical coherence tomography

There is increasing interest in developing a minimally invasive imaging modality to safely evaluate dynamic microscopic changes of the olfactory mucosa and cribriform foramina. Herein, we utilized three-dimensional (3D) optical coherence tomography (OCT) to characterize the ex vivo stratified substructure of olfactory mucosa in rabbits and create 3D reconstructed images of olfactory foramina. Olfactory mucosa and cribriform plates from four New Zealand White rabbits were dissected and imaged using two swept-source OCT systems: (1) 1.3-µm (μm) center wavelength, 100-nm bandwidth, 200-kHz sweep rate, and (2) 1.7-μm center wavelength, 120-nm bandwidth, 90-kHz sweep rate. Volumetric OCT images were compiled to create a 3D reconstruction of the cribriform plate. The ability of OCT to distinguish the olfactory mucosa substructure and foramina was compared to histology. To estimate imaging penetration depth of each system, the first-order exponential decays of depth-resolved intensity were calculated and compared using a paired t-test. Three-dimensional OCT depicted the stratified layered structures within the olfactory mucosa correlating with histology. The epithelium and lamina propria were measured to be 32 μm and 107 μm in 1.3-μm OCT compared to 30 μm and 105 μm in histology. Olfactory foramina were visualized via 3D reconstruction. The 1.7-μm system provided greater depth penetration compared to the 1.3-μm system, allowing for improved foramina visualization. We have shown that OCT can be used to image non-pathologic olfactory mucosa and foramina. Implications for this work include diagnostic and therapeutic potentials for neurorhinological and neurodegenerative diseases.

Ethmoid roof morphometric measurements of a pediatric population using computed tomography

OBJECTIVE

To reveal the anatomical relationships of the ethmoid roof on CT in pediatric case group.

METHODS

We measured the depth of olfactory fossa (DOF), the width of olfactory fossa (WOF), the angle between lateral lamella and cribriform plate (LLCPA), the width of the olfactory cleft (WOC), the length of lateral lamella (LLL), orbital roof fovea to ethmoidal distance (ORFED) and orbital roof to cribriform plate distance (ORCPD) and we determined Keros and LLCPA types from paranasal sinus CT of subjects under 16 years of age retrospectively.

RESULTS

The incidence of Keros type I was higher in females and Keros Type II in males. The ORCPD, DOF and LLL values were found to be higher in 13-16 years age group and WOF and LLCPA in 4-6 years age group. The prevalence of Keros type II was higher in the 13-16 age group, and Keros type I was higher in other age groups. LLCPA type A was the most frequent in all age groups and in both sexes. There was a positive correlation between age and ORCPD, DOF, LLL, and a negative correlation with ORFED, WOF, LLCPA. Olfactory fossa width and depth had a negative correlation. LLCPA had a positive correlation with WOF and a negative correlation with DOF. There was a positive correlation between LLCPA and LLL. DOF and LLL had a positive correlation too.

CONCLUSIONS

Paranasal sinus CT provides useful information about frontal skull base anatomic relations before sinus surgery in pediatric cases.

Development of a novel centrifugal extraction device to collect the olfactory cleft mucus

BACKGROUND

Measuring olfactory cleft mucus biomarkers provides critical insights into the pathogenesis of the olfactory dysfunction.

OBJECTIVES

This study aimed to develop a novel centrifugal extraction device to collect the olfactory cleft mucus.

MATERIAL AND METHODS

The olfactory cleft mucus was collected from 18 patients with chronic rhinosinusitis (CRS) and 10 healthy controls using polyvinyl alcohol (PVA) sponges. Both novel centrifugal extraction devices and traditional devices which consisted of a falcon tube and a syringe shaft were utilized. Levels of Galectin-10 were assessed using the enzyme-linked immunosorbent assay. The olfaction was evaluated with Sniffin' Sticks.

RESULTS

The average extraction efficiency of recovered volume for novel centrifugal extraction devices and traditional devices was 85.44 and 79.15%, respectively. Galectin-10 levels of the olfactory cleft mucus in patients with CRS were significantly higher than that in controls when extracted through novel devices (p < .001). Furthermore, levels of Galectin-10 in patients with CRS significantly correlated with TDI score (p = .020, r = -0.546). There was no significant difference between novel and traditional devices regarding Galectin-10 levels in CRS (p = .966).

CONCLUSIONS AND SIGNIFICANCE

The novel centrifugal extraction device with PVA sponges proved to be a feasible method to collect the olfactory cleft mucus.

Prevalence of respiratory epithelial adenomatoid hamartomas (REAH) associated with nasal polyposis: an epidemiological study - how to diagnose

OBJECTIVES

To highlight the prevalence of respiratory epithelial adenomatoid hamartomas in the olfactory cleft of patients with nasal polyposis. To demonstrate characteristics indicative of hamartoma on the CT scans of paranasal sinuses during surgery and in histopathological exams.

METHODS

Cross-sectional study carried out in Hospital das Clínicas da UFMG and Núcleo de Otorrino BH. We performed 114 nasal endoscopic surgeries for polyposis, between February 2015 and November 2019. We assessed the olfactory cleft width in all preoperative CT scans. Upon seeing an indication of hamartoma on the CT scan, we took a tissue sample from the olfactory cleft during the surgery and sent for histopathological exam. We referred the samples to a pathologist experienced in the anatomopathological diagnosis of respiratory epithelial adenomatoid hamartomas.

RESULTS

Of the 114 patients with polyposis, 54 (47.4%) had olfactory cleft enlargement and, 100% of them had tissue with a dense and hardened polypoid aspect, with a slight cerebriform appearance in this region during the surgery. Histology confirmed a respiratory epithelial adenomatoid hamartoma.

CONCLUSION

This observation suggests that the presence of hamartomas in polyposis is common, but underdiagnosed.

LEVEL OF EVIDENCE

Step 3 (Level 3).

Olfactory dysfunction in cystic fibrosis: Impact of CFTR modulator therapy

BACKGROUND

Elexacaftor-tezacaftor-ivacaftor (ETI) improves pulmonary health and chronic rhinosinusitis (CRS) for people with cystic fibrosis (PwCF), however its impact on olfaction has not been investigated. Olfactory dysfunction impairs quality-of-life (QOL). This study evaluated the impact of ETI on multiple olfactory metrics.

METHODS

Adult PwCF/CRS with CF transmembrane conductance regulator genotype F508del/F508del or F508del/minimal function who clinically initiated ETI participated in a prospective, observational study. Endpoints included changes after 6 months of ETI in quantitative olfactory function (Smell Identification Test, SIT), olfactory QOL (Questionnaire of Olfactory Disorders, QOD) and percent olfactory cleft opacification (%OCO), representing superior nasal cavity inflammation where afferent olfactory neurons are concentrated.

RESULTS

30 PwCF/CRS met inclusion criteria; 25 completed the study. Mean ETI adherence was 93%. At baseline, participants were hyposmic (mean SIT 31.3), had significant %OCO (mean 65.6%), yet reported non-impaired olfactory QOL (mean QOD 6.1). At follow-up, mean SIT worsened mildly (p=0.009), mean %OCO remained stable (p=0.46), and mean QOD improved modestly (p=0.008). No outcomes were impacted by prior modulator use, genotype, nasal polyps, or CF-related diabetes. Prior sinus surgery was associated with QOD improvement (p=0.04). Increased (worse) baseline QOD scores and %OCO were associated with greater improvements (p<0.003), but not SIT (p=0.44).

CONCLUSIONS

ETI was not associated with improvement in quantitative olfaction or olfactory cleft opacification after 6 months. PwCF/CRS have hyposmia but do not report impairment in olfactory QOL. Further study to investigate mechanisms explaining olfactory dysfunction and whether olfaction improves with greater duration of ETI or in younger age groups is warranted.

Comparison of Olfactory Cleft Width and Volumes in Patients with COVID-19 Anosmia and COVID-19 Cases Without Anosmia

Introduction

The aim of this study was to assess the relationship between olfactory cleft width/volume and COVID-19-related anosmia.

Methods

This study consisted of PCR-proven COVID-19 patients. Cases with COVID-19-related anosmia constituted Group 1 and cases without any olfactory dysfunction (OD) throughout COVID-19 infection or after recovery constituted Group 2. A total of 50 patients were included in the study, comprising 24 cases in Group 1 and 26 cases in Group 2. Group 1 patients underwent a 4-item-odor identification test during active symptoms and a Sniffin' Sticks test after reconversion of PCR results to negative. All patients in Group 2 also underwent the Sniffin' Stick test to document normosmia. All cases had paranasal sinus CT performed. Olfactory cleft widths and olfactory volumes were measured. The differences in width and volume between groups and the correlation with odor test scores (threshold-discrimination-identification [TDI]) were calculated. In addition, regression analyzes analysis was performed for cleft widths, volumes, and TDI scores according to age.

Results

Olfactory cleft widths and olfactory volumes were significantly higher in Group 1 than those in Group 2 (p = 0.001; p < 0.01). There was a significant negative correlation between total TDI scores and olfactory cleft widths and total olfactory volumes (r = −0.665; r = −0.731, respectively). Patients younger than 40 years of age had significantly higher right olfactory cleft width, left olfactory cleft width, and olfactory cleft volume than those in patients older than 40 years of age (p = 0.004, p = 0.005, p = 0.003; p < 0,01, respectively). However, patients younger than 40 years of age had a significantly lower total TDI score and in all other values individually (t-d-i) than those in patients older than 40 years of age (p = 0.004; p < 0.01).

Conclusion

Patients with COVID-19-related OD had larger olfactory cleft width and volumes than those without OD in this study. Total TDI score was found to be inversely correlated with cleft width and volume.

Olfactory Bulb MRI and Paranasal Sinus CT Findings in Persistent COVID-19 Anosmia

Background and purpose

There is limited literature consisting of case reports or series on olfactory bulb imaging in COVID-19 olfactory dysfunction. An imaging study with objective clinical correlation is needed in COVID-19 anosmia in order to better understand underlying pathogenesis.

Material and methods

We evaluated 23 patients with persistent COVID-19 olfactory dysfunction. Patients included in this study had a minimum 1-month duration between onset of olfactory dysfunction and evaluation. Olfactory functions were evaluated with Sniffin’ Sticks Test. Paranasal sinus CTs and MRI dedicated to olfactory nerves were acquired. On MRI, quantitative measurements of olfactory bulb volumes and olfactory sulcus depth and qualitative assessment of olfactory bulb morphology, signal intensity, and olfactory nerve filia architecture were performed.

Results

All patients were anosmic at the time of imaging based on olfactory test results. On CT, Olfactory cleft opacification was seen in 73.9% of cases with a mid and posterior segment dominance. 43.5% of cases had below normal olfactory bulb volumes and 60.9% of cases had shallow olfactory sulci. Of all, 54.2% of cases had changes in normal inverted J shape of the bulb. 91.3% of cases had abnormality in olfactory bulb signal intensity in the forms of diffusely increased signal intensity, scattered hyperintense foci or microhemorrhages. Evident clumping of olfactory filia was seen in 34.8% of cases and thinning with scarcity of filia in 17.4%. Primary olfactory cortical signal abnormality was seen in 21.7% of cases.

Conclusion

Our findings indicate olfactory cleft and olfactory bulb abnormalities are seen in COVID-19 anosmia. There was a relatively high percentage of olfactory bulb degeneration. Further longitudinal imaging studies could shed light on the mechanism of olfactory neuronal pathway injury in COVID-19 anosmia.

Paranasal sinuses computed tomography findings in anosmia of COVID-19

Objective

Olfactory dysfunction in coronavirus disease-2019 (COVID-19) is poorly understood. Thus, mechanistic data are needed to elucidate the pathophysiological drivers of anosmia of COVID-19.

Methods

We performed the current study in patients who presented with anosmia and COVID-19 as documented by the polymerase chain reaction (PCR) assay between April 1st and May 15st, 2020. We assessed for the conductive causes of anosmia with computed tomography (CT) of paranasal sinuses.

Results

49 patients who presented with anosmia and positive PCR assay for COVID-19 were included. The average age was 45 ± 12.2 years. Complete anosmia was present in 85.7% of patients and 91.8% of patients reported sudden onset of olfactory dysfunction. Taste disturbance was common (75.5%). There were no significant pathological changes in the paranasal sinuses on CT scans. Olfactory cleft and ethmoid sinuses appeared normal while in other sinuses, partial opacification was detected only in some cases.

Conclusion

We did not find significant mucosal changes or olfactory cleft abnormality on CT imaging in patients with anosmia of COVID-19. Conductive causes of anosmia (i.e., mucosal disease) do not seem play a significant role in anosmia of COVID-19.

How to identify the anterior cribriform plate in the medial approach to the frontal sinus

Draf III frontal sinusotomy is one of the most complex surgical procedures on the frontal sinus, designed to limit the risks of restenosis by ensuring unification of the two ostia and resection of the floor of the sinus. This procedure requires a good knowledge of anatomy and sufficient surgical expertise to avoid the risk of CSF leak and to limit the risk of restenosis. The surgeon can use various landmarks, consisting of foramina, bone grooves and arteries located on the anterior part of the cribriform plate to guide the procedure. The purpose of this technical note is to explain the use of these landmarks to ensure safe Draf III frontal sinusotomy via a medial approach.

A novel surgical treatment for long lasting unilateral peripheral parosmia: Olfactory cleft blocking technique

The treatment of qualitative olfactory disease is challenging. We aimed to treat parosmia using a new minimally invasive surgical technique-the olfactory cleft blocking technique- by preventing odorants from reaching the olfactory epithelium. A novel surgical procedure for blocking the anterior and inferior openings of the olfactory cleft was accomplished in a patient with unilateral persistent peripheral parosmia. The HRCT and endoscopy were performed preoperatively and postoperatively to evaluate the anatomical structure of the olfactory cleft. The T&T olfactometer was used to assess the preoperative and postoperative olfactory function. After surgery, the patient's parosmia disappeared. Endoscopic examination and CT scan showed complete obstruction of the anterior and inferior portions of the olfactory cleft. No recurrence was reported during a 2-year follow-up. No surgical complications were reported except olfactory loss in the operative nostril. For patients with long-term unilateral peripheral olfactory dysfunction, the olfactory cleft blocking technique seems a novel, simple, safe and effective treatment. Further studies are required with a larger number of patients in order to access success rate.

Osteoma involving the olfactory groove: evaluation of the risk of a CSF leak during endoscopic surgery

Purpose

The olfactory groove (OG) is a common site of iatrogenic cerebrospinal fluid (CSF) leak during endoscopic sinus surgery. We aimed to evaluate the prevalence of CSF leak during endoscopic removal of osteomas involving the OG and identify CT findings indicating increased risk of this complication.

Methods

A retrospective review was conducted of patients operated on for frontoethmoidal osteoma from 11 years in a single institution. A retrospective review of the literature, 1999 to 2019, of perioperative complications in patients operated on for frontoethmoidal osteoma using endoscopic or combined approaches.

Results

Case series: 73 patients were identified including 17 with the OG involvement. The only case of CSF leak occurred in a patient with spongious part of osteoma at the OG. Among six osteomas with spongious component at the OG, one was detached and five had to be drilled down, leaving a small remnant in four. In contrast, all the 11 osteomas with ivory part at the OG were safely detached and completely removed from the OG after debulking. The prevalence of CSF leak was not statistically different between the patients without and with involvement of the OG. Systematic review of the literature: Among the 273 identified patients there were 8 cases of intraoperative CSF leaks (3%) including 2 from the OG (0.7%).

Conclusion

Involvement of the OG does not significantly increase the risk of intraoperative CSF leak. However, this risk may be increased in patients with the spongious part of the tumor attached to the OG.

Respiratory Epithelial Adenomatoid Hamartoma (REAH) in the Olfactory Cleft: Often Masked by Bilateral Nasal Polyps

Respiratory epithelial adenomatoid hamartoma (REAH) is a distinct non-neoplastic entity originating from anterior olfactory cleft in the nasal cavity, often going unnoticed. Clinically, REAH presents as unilateral or bilateral nasal polyps. Our aim is to expand the understanding of bilateral REAH associated with nasal polyposis with respect to clinical, radiological and histopathological features for better clinical outcomes. Our analysis includes patients presenting as bilateral nasal polyps, whose CT-PNS showed opacity in olfactory clefts. During endoscopic sinus surgery, the lesions in the olfactory cleft (medial-to-middle turbinate) were identified and the specimens from olfactory cleft and ethmoid sinus cavity were subjected separately to histopathological analysis. Six patients (average age 50 years, 83% male) of bilateral REAH with nasal obstruction of > 3 years were analysed. On nasal endoscopy, the polypoid masses in the olfactory cleft and in the ethmoids did not show any gross differences. However, polypoidal masses from the olfactory cleft bled more during biopsy and excision. Histopathological study of these masses revealed the closely arranged round to oval glands (with few dilated glands) lined by ciliated columnar epithelium in mildly edematous stroma, confirming the presence of REAH. REAH is an often overlooked lesion in the nasal cavity, arising from olfactory cleft. The presence of nasal polyposis obscures this lesion, resulting in under diagnosis. The prompt identification with high index of suspicion by the otorhinolaryngologists helps in accurate histopathological diagnosis thereby improving clinical outcomes.

Age-related differences in olfactory cleft volume in adults: A computational volumetric study

OBJECTIVES/HYPOTHESIS

There is a growing need to understand the underlying mechanisms of age-related olfactory dysfunction with the increasing proportion of older adults over the next 20 years. Despite the importance of olfactory cleft (OC) volumes on odorant deposition and olfactory function, little is known about age-related changes to OC volume. The goal of this study was to use automated techniques in a cross-sectional design to investigate the extent to which OC volumes vary with age and determine the spatial specificity of any age-related effects.

STUDY DESIGN

Retrospective cross-sectional study.

METHODS

Deformation-based morphometry was utilized to measure OC and sinus volumes in two independent samples of 101 (Medical University of South Carolina [MUSC] sample) and 95 (Hammersmith sample) healthy adults who underwent T1-weighted magnetic resonance imaging, with the Hammersmith sample serving as a replication sample.

RESULTS

The mean age of the MUSC and Hammersmith samples were 54.9 ± 17.0 years and 52.1 years ± 15.7 years, respectively. In both samples, there was a significant positive association between age and OC volume that occurred at a constant rate across the lifespan (Cohen's f² of 0.065 in the MUSC sample and 0.110 in the Hammersmith sample). Age-associated OC volume increases occurred in conjunction with decreases in sinus volumes as well as increases in non-OC nasal cavity volumes.

CONCLUSIONS

In this cross-sectional study, there is an increase in OC volume with increasing age that occurs in the context of broad age-associated differences in sinonasal anatomy. Future studies should investigate the impact of age-associated differences in intranasal anatomy on nasal airflow, odorant deposition, and olfactory function.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:E55-E60, 2019.

Intestinal and non-intestinal nasal cavity adenocarcinoma: Impact of wood dust exposure

The aim of the present study was to investigate the role of wood dust exposure in intestinal (ITAC) and non-intestinal type (non-ITAC) nasal adenocarcinoma, so as to improve understanding of the oncogenic mechanisms in the light of the recent literature and of evo-devo concepts.

MATERIALS AND METHODS

All consecutive patients operated in our institution for nasal adenocarcinoma diagnosed on anatomopathology between May 2004 and February 2014 were included. Surgical specimens were examined twice by independent pathologists, blind to wood dust exposure status. Clinical and demographic data, including wood dust exposure, were collected for the two groups (ITAC and non-IATC).

RESULTS

90 patients (84 ITAC, 6 non-ITAC) were included. No non-ITAC patients had history of wood dust exposure, versus 83/84 cases (99%) in ITAC (mean exposure duration: 30±16 years; range 2-65 years). Only 12 ITAC patients (18%) were still exposed at diagnosis. ITAC may develop long after the end of wood dust exposure (up to 60 years). Eight patients (12%) had exposure durations of less than 5 years. Latency between onset of exposure and onset of disease did not decrease with exposure duration.

CONCLUSION

Exposure to wood dust, even for short periods of time, incurs a risk of developing ITAC, usually after a long latency period. Any exposure requires lifetime follow-up, to ensure prompt treatment. Factors leading to the development of nasal ITAC and non-ITAC are probably different. The analogy with Barret's esophagus and esophageal adenocarcinoma may shed light on the oncogenesis of nasal ITAC.

Olfactory cleft dilatation

The surgical technique of olfactory cleft dilatation consists in transmucosal lateral fracture-dislocation of the lateral wall of each olfactory cleft (i.e., of the turbinate wall of the ethmoid, composed, from anterior to posterior, of the middle, superior and supreme turbinates), in order to get access to the recess hosting the human olfactory mucosa and to the roof of the olfactory cleft (i.e., cribriform plate), with minimal trauma to the mucosa. Olfactory cleft dilatation is indicated for dysosmia secondary to constitutional stenosis of the olfactory clefts due to abnormal development of the ethmoid. Constitutional stenosis of the olfactory clefts should be differentiated from inflammatory obstruction and other diseases of the olfactory clefts, and especially from respiratory epithelial adenomatoid hamartoma, which enlarges the olfactory clefts and must be treated by resection. The technique of olfactory cleft dilatation is illustrated by three surgical cases. There was clear improvement in dysosmia in all three cases, without any complications. The place of constitutional olfactory cleft stenosis needs still to be defined in both diagnosis and treatment of dysosmia.

Olfactory cleft evaluation: a predictor for olfactory function in smell-impaired patients?

OBJECTIVE

In this study, we introduce an extension of previous work by Soler et al. (Int Forum Allergy Rhinol 6(3):293-298, 2016) on a modified endoscopic scoring system of the Lund-Kennedy Score (focusing on the olfactory cleft) to evaluate its correlation with the olfactory function in patients with various smell disorders.

STUDY DESIGN

A prospective cohort study.

METHODS

Two-hundred and eighty-eight participants were included and categorized in five groups according to the cause of their olfactory disorder: (0) control, (1) idiopathic, (2) sino-nasal, (3) postinfectious and (4) post traumatic olfactory loss. Olfaction was evaluated using the "Sniffin' Sticks" test. The classical Lund-Kennedy scoring and a new olfactory cleft specific Lund-Kennedy scoring (OC-LK) were performed to evaluate mucosal changes.

RESULTS

Significantly higher OC-LK scores on both sides were found in smell-impaired patients as compared to normosmic controls. When comparing the 4 groups, a significant difference of the OC-LK score were present between the sino-nasal and all other groups. Most importantly, significant negative correlations with strong effects were shown in the sino-nasal group between the OC-LK score and odor discrimination and odor identification. However, no such correlation emerged between the classical LK score and smell function.

CONCLUSION

Olfactory cleft evaluation using the OC-LK score correlates with the olfactory function in patients with sino-nasal smell disorder. This diagnostic tool may reflect the underlying pathophysiological mechanism of sino-nasal smell loss, and therefore, should complement olfactory diagnostics in patients with sino-nasal smell disorder.

Usefulness of our proposed olfactory scoring system during endoscopic sinus surgery in patients with chronic rhinosinusitis

INTRODUCTION

The primary aim of the current study was to examine the usefulness of our proposed olfactory scoring system in chronic rhinosinusitis (CRS) patients with olfactory disorders (n = 213) receiving endoscopic sinus surgery (ESS).

MATERIALS AND METHODS

Analyzed patients were divided into two groups: an eosinophilic CRS (ECRS) group (n = 153); and a non-ECRS group (n = 60). The T&T recognition threshold test was used to evaluate olfaction at baseline and at 3 and 12 months after ESS. Patients with mean recognition threshold < 2.0 at 3 or 12 months or with a decrease of ≥ 1.0 as compared with baseline were defined as showing clinical improvement. We scored mucosal conditions as normal (0 points), edema (1 point), and polyp (2 points) at the canopy of olfactory cleft (OC), middle and superior turbinates, superior nasal meatus, and sphenoethmoidal recess during ESS. The total score of OCs (SOCs) was calculated (range 0-20 points). We compared SOCs between ECRS and non-ECRS groups. Factors related to olfactory improvement were also investigated using uni- and multivariate analyses.

RESULTS

SOCs in the ECRS and non-ECRS groups showed significant correlations with mean recognition thresholds at baseline and at 3 and 12 months. In the multivariate analysis for predicting improvement of mean recognition threshold, lower SOCs were significantly associated with olfactory improvement factors at 3 and 12 months postoperatively in the ECRS group.

CONCLUSION

SOCs appears promising for estimating olfactory prognosis after ESS in CRS patients.

Endoscopic surgery of the olfactory cleft

The olfactory cleft is the specific site of development of many tumours (respiratory epithelial adenomatoid hamartoma, intestinal-type adenocarcinoma, neuroblastoma, inverted papilloma, glomangiopericytoma, etc.) and is also the site of CSF rhinorrhoea via the cribriform plate (cribri-rhinorrhoea). Olfactory cleft surgery must therefore be considered to be a specific type of surgery, complementary to ethmoidal labyrinth surgery and anterior skull base surgery. Olfactory cleft tumours can be resected according to five different surgical procedures: olfactory cleft mucosal resection, partial resection of the olfactory cleft, total resection of the olfactory cleft, unilateral endoscopic anterior skull base resection, and bilateral endoscopic anterior skull base resection. The diagnosis and closure of cribri-rhinorrhoea (i.e. documented CSF rhinorrhoea, demonstrated to arise from the cribriform plate during endoscopic examination of the olfactory cleft under general anaesthesia in a patient with no localizing signs on imaging) completes this range of treatment options.

Comparison of endoscopic and external resections for sinonasal instestinal-type adenocarcinoma

Endoscopic sinus surgery (ESS) is considered as a valid option in the management of nasal adenocarcinoma (ADC). Comparative studies with open approaches are still required. A monocentric retrospective study was carried out from May 2002 to December 2013, including 43 patients with intestinal-type adenocarcinoma of the ethmoid sinus. Non-resectable tumours or recurrences were excluded. Before 2008, open approach with lateral rhinotomy (LR) was performed as the gold standard of treatment. From 2008, ESS was systematically used as a first-line option as long as a complete resection was achievable. Adjuvant radiation therapy was delivered (RT) for all the patients. LR and ESS were performed in, respectively, 23 and 20 patients. The two groups were comparable in terms of age, occupational dust exposure, histopathological subtypes, and T stage based on the pathological assessment of the specimen (10 pT2, 26 pT3, 2 pT4a, and 5 pT4b). The tumour origin was mainly located in the olfactory cleft with the involvement of the cribriform plate in 60 % of patients. No major complication was observed in ESS group with a reduced hospital stay (5.6 vs 7.6 days). The disease-free survival was not different between LR and ESS groups over a mean follow-up period of 6.6 years. Even for local advanced stages with skull base involvement, we confirm the reliability and the advantages of ESS in terms of oncological outcomes and morbidity. We advocate complete excision of the olfactory cleft to ensure an appropriate control of the tumoral origin.

The administration of nasal drops in the "Kaiteki" position allows for delivery of the drug to the olfactory cleft: a pilot study in healthy subjects

Systemic treatment with corticosteroids shows therapeutic effects, few patients benefit from intranasal topical drug application, probably due to limited access of the drug to the olfactory epithelium. The aim of the present study was to investigate how drops distribute within the nasal cavity when the "Kaiteki" position is performed. Thirteen healthy volunteers participated. Subjects were lying on the side with the head tilted and the chin turned upward. Blue liquid was used to visualize the intranasal distribution of the nasal drops. The investigation was carried out using photo documentation thorough nasal endoscopy; the intranasal distribution of the dye was judged by two independent observers in both a decongested state and a natural state where no decongestants had been used. With regard to the main criterion of this study, using the "Kaiteki" position, nasal drops reached the olfactory cleft in 96 % of the decongested cases and 75 % of the cases who had not been decongested. However, this difference was not statistically different. Because the "Kaiteki" maneuver is not too difficult to perform, it is more likely that topical steroids can be helpful in cases of olfactory loss.

MRI in respiratory epithelial adenomatoid hamartoma of nasal cavities

This is a report of six cases of respiratory epithelial adenomatoid hamartoma of the nasal cavities that were characterized by: symptoms of nasal obstruction and dysosmia; endoscopic appearances of bilateral nasal polyposis affecting the olfactory clefts; CT imaging showing enlargement of the olfactory clefts; MRI (rarely reported in the literature) revealing clearly delineated cerebriform tissue filling in the olfactory clefts; histological confirmation in all cases; and recovery after surgical endoscopic resection without the need for associated sinus surgery.

Topical beclomethasone in the therapy of smelling disorders-a new application technique

Systemic corticosteroid is the first-line-treatment for olfactory dysfunction of sinonasal origin but is afflicted with many side-effects. Topic corticosteroid does not reach the same efficacy but has a remarkable safety profile. In this trial we investigated the efficacy of topic therapy with beclomethasone (BDP) -spray. The drug was applied precisely to the olfactory cleft by a special spraying top-part. In addition we determined extinction and volume of a gelaspon sponge placed in the olfactory cleft to show the difference of the topical spray application. 18 patients with anosmia or hyposmia of different genesis and duration applied BDP-spray twice daily for four weeks. The olfactory function was determined using the TDI score ('Sniffin'-Sticks test battery'). Factors correlated with therapy efficacy were assessed. The median TDI score increased from 13.5 (0-25) at the beginning to 18.5 (1-26) after therapy of four weeks (P = 0.005). The extinction and volume in the moistened sponge was more than two times greater with the top-part than without. The direct application of BDP-spray to the olfactory cleft attained superior therapeutic effects than a usual applied mometasone spray, but did not perform as good as systemic corticosteroid treatment.