Delivering Therapy to the Olfactory Cleft: A Comparison of the Various Methods of Administering Topical Nasal Medications

Background and objective Chronic rhinosinusitis (CRS) is an inflammatory condition affecting the nasal mucosa, and it causes olfactory dysfunction (OD) in up to 78.2% of patients. Corticosteroids are the mainstay of treatment to shrink nasal polyposis, reduce inflammation, and improve olfactory function. While many delivery methods for topical nasal corticosteroids exist, there is scarce data on the efficacy of the various medication delivery methods to the olfactory cleft (OC). In light of this, this study aimed to compare the following delivery methods to the OC: conventional nasal spray (NS), nasal drops in the Kaiteki position (KP), and exhalation delivery system (EDS). Methods We evaluated 16 sinonasal cavities from eight cadaver specimens in this study. Each sinonasal cavity was administered fluorescein dye solution via NS, KP, and EDS. Following administration, nasal endoscopy was employed to capture staining patterns in the OC. OC staining was rated with scores ranging from 0 (no staining) to 3 (heavy staining) after each administration of dye solution. Mean OC staining ratings were calculated and compared using the Kruskal-Wallis rank sum test and the Wilcoxon signed-rank test. Results The mean OC staining score for the different delivery methods was as follows - NS: 1.095 ± 1.008, EDS: 0.670 ± 0.674, and KP: 2.038 ± 1.097. Nasal drops in the KP had a significantly higher staining score compared to NS (p=0.041) and EDS (p=0.003). However, there was no significant difference in staining scores between NS and EDS. Conclusions Nasal drops in the KP are more effective at reaching the OC than NS or EDS and should be considered as a first-line modality for administering topical medications when treating OD.

Predictive significance of computed tomography in bilateral sinonasal respiratory epithelial adenomatoid hamartoma

KEY POINTS

Respiratory epithelial adenomatoid hamartoma (REAH) is easily confused with nasal polyps (NP). The typical manifestation of REAH on CT is the enlargement of bilateral olfactory clefts (OCs). The widening of the OCs in the CT scan is a biomarker for diagnosing REAH associated with NP.

Spatial analysis of transnasal olfactory cleft access: a computed tomography study

Objective

To our knowledge, the spatial access of naris to olfactory cleft has not been quantified. We aimed to study the relationship and space of middle turbinate, septum, anterior nasal spine and cribriform plate to improve topical medication delivery and drug applicators.

Methods

One hundred CT scans of patients (50 males, 50 females) over the age of 18 were included. Subjects with radiographic sinonasal pathology, previous surgery, or specific variant nasal anatomy were excluded. Scans were independently reviewed and bilateral measurements on bony landmarks were taken by two blinded authors. Inter-rater reliability was analysed with intraclass correlation.

Results

The average age was 46.26 years (σ = 14.0). Average distance from the anterior nasal spine to olfactory cleft was 52.3 mm (σ = 4.2 mm), and the average length of cribriform plate was 18.8 mm (σ = 3.8) with an angle relative to hard palate averaging -8.8 degrees below parallel (σ = 5.5 degree). The widths of the olfactory cleft at anterior and posterior edges of cribriform plate were 2.3 mm (σ = 0.7 mm) and 2.0 mm (σ = 0.7 mm).

Conclusions

The findings suggest a 52.3 mm distance from the naris to the anterior border of cribriform plate. The average width along this path was 3.2 mm, suggesting devices narrower than this could potentiate direct drug delivery access.

Endoscopic balloon dilatation of the olfactory cleft - a feasibility study of a novel technique in cadavers

Objective

Smell dysfunctions are common with almost 20% percent of the population affected. There are no interventional solutions for these patients. The aim of this study is to investigate the feasibility and security of the balloon dilatation technique.

Methods

This paper describes interventional steps and determines the feasibility and safety of endoscopic olfactory cleft dilatation via balloon device. We included 10 nasal cavities in the study and dilated olfactory cleft areas via balloon device.

Results

We could smoothly perform the procedure and did not observe any fractures on the skull base or olfactory cleft of the cadavers after dilatation.

Conclusions

A combination of this intervention with medical treatments can be promising for smell dysfunctions.

Radiologic Assessment of the Sinonasal Tract, Nasopharynx and Mastoid Cavity in Patients with SARS-Cov-2 Infection Presenting with Acute Neurological Symptoms

BACKGROUND

Acute neurological sequela in patients with COVID-19 infection include acute thromboembolic infarcts related to cytokine storm and post infectious immune activation resulting in a prothrombotic state. Radiologic imaging studies of the sinonasal tract and mastoid cavity in patients with COVID-19 infection are sparse and limited to case series. In this report, we investigate the radiologic involvement of nasal cavity, nasopharynx, paranasal sinuses, and mastoid cavity in patients with SARS-CoV-2 infection who presented with acute neurological symptoms.

METHODS

Retrospective review of medical records and neuroradiologic imaging in patients diagnosed with acute COVID-19 infection who presented with acute neurological symptoms to assess radiologic prevalence of sinus and mastoid disease and its correlation to upper respiratory tract symptoms.

RESULTS

Of the 55 patients, 23 (42%) had partial sinus opacification, with no evidence for complete sinus opacification. The ethmoid sinus was the most commonly affected (16/55 or 29%). An air fluid level was noted in 6/55 (11%) patients, most commonly in the maxillary sinus. Olfactory recess and mastoid opacification were uncommon. There was no evidence of bony destruction in any of the studies, Cough, nasal congestion, rhinorrhea, and sore throat were not significantly associated with any radiological findings.

CONCLUSION

In patients who present with acute neurological symptoms, COVID-19 infection is characterized by limited and mild mucosal disease within the sinuses, nasopharynx and mastoid cavity.

LEVEL OF EVIDENCE

4.

A Comparison between Mygind and Kaiteki positions in administration of drops to the olfactory cleft

OBJECTIVES

Topical nasal steroids are a common treatment intervention for olfactory dysfunction. Penetration of topical treatment to the olfactory cleft (OC), such as nasal drops, is greatly dependent on the position of the head when the treatment is administered. We aimed to examine the penetrance of nasal drops to the OC in two different head positions: the Mygind (lying head back) position and the Kaiteki position.

DESIGN AND SETTING

The specimens were firstly positioned in Mygind, and thereafter in Kaiteki positions. Nasal drops mixed with blue food dye were administered into the nostrils in each of the head position. Endoscopic videos were recorded, and two blinded observers scored the extent of olfactory cleft penetration (OCP) using a 4-point scale (0 = none, 3 = heavy).

PARTICIPANTS

Twelve fresh-frozen cadaver specimens.

MAIN OUTCOME MEASURES

Penetration of the dye into the OC.

RESULTS

The mean score of nasal drops penetrance to the OC in the Mygind position was 1.34 (standard deviation, SD = 0.92), as compared to 1.76 (SD = 0.65) in the Kaiteki position. The difference in the OCP score between the two groups was not statistically significant (P > .05).

CONCLUSION

Both Mygind and Kaiteki head positions are reasonable options for patients considering topical nasal drops for olfaction impairment. The preference of one position over the other should be determined by patient's preference and comfort.

Preoperative Endovascular Embolization in an Easily Bleeding Respiratory Epithelial Adenomatoid Hamartoma of the Olfactory Cleft: A Case Report

Respiratory epithelial adenomatoid hamartomas (REAHs) are rare tumors occurring in the nasal cavity and sinuses, and their etiology is unknown. REAH is a relatively recently established lesion and is often misdiagnosed as nasal polyposis or other tumors. Preoperative endovascular embolization for sinonasal tumors is now widely accepted as an effective method to reduce blood loss, soften the tumor, and facilitate surgical procedures. However, to the best of our knowledge, there are no reports of the requirement for preoperative embolization in the management of REAH. Here, we present a 70-year-old man with an easily bleeding REAH of the olfactory cleft, vascularized by branches of the bilateral internal and external carotid arteries. We removed the tumor endoscopically after preoperative embolization of the bilateral sphenopalatine arteries. Histological investigation revealed an intratumoral hemorrhage accompanying the REAH, with no evidence of a residual or recurrent tumor during the last follow-up at 3 months. In conclusion, accurate preoperative diagnosis and proper preoperative interventions such as embolization are needed for safe and adequate treatment of REAHs that have an abundant blood flow.

Radiological Markers of the Olfactory Cleft: Relations to Unilateral Orthonasal and Retronasal Olfactory Function

The opacification of the olfactory cleft (OC) has been associated with birhinal orthonasal olfaction in patients with chronic rhinosinusitis (CRS). The aim of this study was to determine the associations between monorhinal and birhinal orthonasal, and retronasal olfaction with radiological markers of the OC in a cohort of patients with CRS. Results were analyzed in a CRS-cohort including 13 patients with nasal polyposis (CRSwNP) and 12 patients with non-eosinophilic CRS (non-eCRS). Monorhinal and birhinal orthonasal olfactory function, and OC-air volume were higher in non-eCRS compared CRSwNP. OC-opacification was also higher in CRSwNP compared to non-eCRS. In the entire CRS-cohort, those with higher OC-opacification showed significantly lower orthonasal and retronasal olfactory test results compared to those with lower OC-opacification across all three coronal planes. Similarly, higher unilateral OC-opacification was also associated with lower ipsilateral orthonasal olfactory function. Correlation analysis further revealed a positive correlation between monorhinal and birhinal orthonasal olfaction with ipsilateral and overall OC-air volume. Likewise, birhinal and monorhinal orthonasal, and retronasal olfactory test results correlated negatively with the overall and ipsilateral Lund-Mackay scores. Monorhinal and birhinal orthonasal, and retronasal olfactory function were lower in CRS patients with higher ipsilateral and overall OC-opacification compared to those with lower OC-opacification.

Olfactory Cleft Measurements and COVID-19-Related Anosmia

Objective

This study aimed to investigate the differences in olfactory cleft (OC) morphology in coronavirus disease 2019 (COVID-19) anosmia compared to control subjects and postviral anosmia related to infection other than severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Study Design

Prospective.

Setting

This study comprises 91 cases, including 24 cases with anosmia due to SARS-CoV-2, 38 patients with olfactory dysfunction (OD) due to viral infection other than SARS-CoV-2, and a control group of 29 normosmic cases.

Methods

All cases had paranasal sinus computed tomography (CT), and cases with OD had magnetic resonance imaging (MRI) dedicated to the olfactory nerve. The OC width and volumes were measured on CT, and T2-weighted signal intensity (SI), olfactory bulb volumes, and olfactory sulcus depths were assessed on MRI.

Results

This study showed 3 major findings: the right and left OC widths were significantly wider in anosmic patients due to SARS-CoV-2 (group 1) or OD due to non–SARS-CoV-2 viral infection (group 2) when compared to healthy controls. OC volumes were significantly higher in group 1 or 2 than in healthy controls, and T2 SI of OC area was higher in groups 1 and 2 than in healthy controls. There was no significant difference in olfactory bulb volumes and olfactory sulcus depths on MRI among groups 1 and 2.

Conclusion

In this study, patients with COVID-19 anosmia had higher OC widths and volumes compared to control subjects. In addition, there was higher T2 SI of the olfactory bulb in COVID-19 anosmia compared to control subjects, suggesting underlying inflammatory changes. There was a significant negative correlation between these morphological findings and threshold discrimination identification scores.

Level of Evidence

Level 4.

Alveolar Soft-Part Sarcoma in Olfactory Cleft: A Case Report and Clinicopathological Review

Sinonasal alveolar soft-part sarcoma (ASPS) is a rare malignant disease that comprises 0.4% to 1.2% of all soft-tissue sarcomas. Alveolar soft-part sarcoma is usually difficult to diagnose because it has many clinical and pathological mimickers. In this case study, ASPS occurred in the olfactory cleft, representing the second case in this location in the literature. This article presents the clinical presentation, radiologic, and histopathological case, and reviews the literature regarding the differentials.

Reversible obstruction of the olfactory cleft: impact on olfactory perception and nasal patency

BACKGROUND

Temporary disruption of sensory input can be studied relatively easily for vision or hearing by covering the eyes or ears. In contrast, closing the nostrils affects not only the sense of smell, but also the ability to breathe through the nose and humidify and warm inhaled air. We hypothesized that filling the olfactory cleft (OC) with dissolvable nasal dressing (foam) would temporarily block olfaction while respecting nasal airflow.

METHODS

In 30 healthy volunteers, the OC was unilaterally obstructed in a back-to-front fashion. Orthonasal and retronasal olfactory function were tested before and after foam application. Ratings of odors and subjective nasal patency (SNP) were collected. Peak nasal inspiratory flow (PNIF) was used to measure nasal patency.

RESULTS

Foam was safely applied in every case using minimal instruments. No complications were reported. Orthonasal and retronasal test results decreased significantly in overall participants (all p < 0.0008). Indicating temporary anosmia, 3 subjects reached the lowest possible score for odor-threshold testing, with corresponding drops in retronasal test scores. PNIF values before and after foam application were not significantly different (p = 0.11). SNP ratings decreased slightly, but not significantly (p = 0.052). Odor-intensity ratings dropped significantly (all p < 0.05).

CONCLUSION

The OC can be safely obstructed with dissolvable nasal dressing, resulting in a decrease in odor-intensity and orthonasal and retronasal olfactory function test scores. This procedure may serve as a hyposmia model that maintains normal nasal airflow.

Olfactory Cleft Width and Volume: Possible Risk Factors for Postinfectious Olfactory Dysfunction

OBJECTIVES/HYPOTHESIS

Upper respiratory tract infections are a common cause of temporary and permanent olfactory dysfunction in the general population. Postviral or postinfectious olfactory loss (PIOL) develops only in rare cases. The aim of this study was to investigate the anatomical features of olfactory cleft (OC) in patients with PIOL to shed light on possible predisposing factors for PIOL.

STUDY DESIGN

Retrospective study.

METHODS

We retrospectively evaluated paranasal sinus computed tomography (CT) scan results of patients diagnosed with PIOL. A control group consisted of normosmic individuals who underwent paranasal sinus CT scans before septoplasty surgery. We compared the olfactory fossa depth, OC width, and volume on the CT scans of the PIOL and control groups.

RESULTS

In total, 71 individuals fulfilled the study criteria (PIOL group, n = 32; control group, n = 39). There was no statistically significant difference in the olfactory fossa depth in the two groups. The OC width and volume in the PIOL group was found to be significantly increased than that in the control group (P < .001 for both).

CONCLUSIONS

Patients with PIOL had increased OC width and volume than the healthy controls. An extra-wide olfactory cleft may be a predisposing factor in the pathogenesis of PIOL.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:5-9, 2021.

Respiratory Epithelial Adenomatoid Hamartoma is Frequent in Olfactory Cleft After Nasalization

OBJECTIVES

To assess the site and histopathology of polyps at the first revision surgery for recurrent nasal polyposis (NP) after radical ethmoidectomy (nasalization).

STUDY DESIGN

Retrospective study.

METHODS

Between January 2008 and December 2015, a total of 62 patients having undergone revision surgery for recurrent NP after nasalization were included. The site and histology of the recurrence of polyps were analyzed according to operative and pathological reports.

RESULTS

Histology showed classical inflammatory nasal polyps (CINP) in 91% of nasal cavities at primary surgery versus respiratory epithelial adenomatoid hamartoma (REAH) or REAH associated to CINP in 54.8% at revision surgery (P < .0001). Polyps were principally observed in the ethmoidal complex in 70% of nasal cavities during primary surgery and in the olfactory clefts in 88.7% during revision surgery (P < .0001). The mean interval between nasalization and first revision surgery was 8.8 ± 4.4 years (0.4-21.7 years). This interval was significantly shorter for grade 3 polyps, polyps removed from both ethmoidal complex and olfactory cleft at primary surgery, association of CINP and REAH at primary surgery, and when primary surgery had preserved the middle turbinates.

CONCLUSION

Polyp recurrences after nasalization were mainly observed in the olfactory clefts and can be different histological features: inflammatory polyps, respiratory epithelial adenomatoid hamartoma, or a combination of both.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2098-2104, 2020.

Compartmentalized endoscopic resection of the olfactory cleft for nasal intestinal adenocarcinomas

BACKGROUND

The purpose of this study was to describe the pathology of the different compartments in endoscopic resection of nasal intestinal-type adenocarcinomas (ITACs) and its relationships with oncologic outcomes.

METHODS

This retrospective study included all patients endoscopically operated for nasal ITACs, followed by radiotherapy in the majority of cases, between 2004 and 2014. The surgery systematically separated 3 compartments: ethmoid lateral mass, olfactory cleft, and anterior cranial fossa (in cases with skull-base invasion) to analyze their pathological "focal" or "massive" invasion by the tumor.

RESULTS

Sixty-seven patients (aged 69.2 ± 9.8 years) were included. Twenty-nine patients (43.3%) had only pathological focal invasion. At 61.0 ± 41.7 months of mean follow-up, the recurrence rates were 34.2% in the group with massive invasion and 10.3% in the group with focal invasion (P = .023). The disease-specific death rate had a tendency to be higher in the group with massive invasion (23.7% vs 6.9% for the group with focal invasion; P = .097). By Kaplan-Meier analysis, the 5-year disease-specific survival rate was better in the group with focal invasion than the group with massive invasion (P = .01). The 5-year overall survival was not different between the 2 groups (47.4% and 65.5% for focal invasion and massive invasion respectively; P = .14).

CONCLUSION

Compartmentalized endoscopic resection, combined with postoperative radiotherapy, is one way to operate on nasal ITACs with good oncologic outcomes.

A Typical but Underdiagnosed Nasal Cavity Mass

Respiratory epithelial adenomatoid hamartoma is a relatively new diagnosis, only added to the World Health Organization classification of tumours in 2005. The lesion results from non-neoplastic overgrowth of glandular tissue in the nasal cavity and rarely in de sinus cavities and is often associated with nasal polyposis. The classical appearance of a bilateral mass in the olfactory cleft causing widening of the olfactory cleft allows the radiologist to suggest the diagnosis on computed tomography or magnetic resonance imaging.

Multicenter assessment of exclusive endoscopic endonasal approach for the treatment of 53 olfactory neuroblastomas

BACKGROUND

Given the particularities of olfactory neuroblastoma (ONB) and the lack of studies on the subject, a multicenter collaborative study was conducted to assess treatment strategy.

METHODS

Fifty-three patients with ONB were included from the French Rare Head and Neck Cancer Expert Network (REFCOR) database: 16T1, 8T2, 19T3, and 10T4. All cases were treated endoscopically with skull base removal and repair in 26 cases (49%) and without external craniotomy.

RESULTS

The overall survival (OS) and disease-free survival (DFS) rates at 5 years were 87% and 71%, respectively, with mean follow-up of 45.4 ± 26.5 months. The complication rate was 18.8% with 4 cases of meningitis. Pathological analysis showed positive margins in 26.8%, notably on the dura-mater and periorbita, without impairment of OS or DFS. Forty-eight patients received adjuvant radiotherapy on T ± N. Ten patients had a recurrence (18.9%). Six patients died of their disease. Prophylactic neck irradiation seemed to reduce the recurrence rate.

CONCLUSION

Exclusively endoscopic treatment proved efficient and reliable in a large controlled series.

First Steps to Develop and Validate a CFPD Model in Order to Support the Design of Nose-to-Brain Delivered Biopharmaceuticals

PURPOSE

Aerosol particle deposition in the human nasal cavity is of high interest in particular for intranasal central nervous system (CNS) drug delivery via the olfactory cleft. The objective of this study was the development and comparison of a numerical and experimental model to investigate various parameters for olfactory particle deposition within the complex anatomical nasal geometry.

METHODS

Based on a standardized nasal cavity, a computational fluid and particle dynamics (CFPD) model was developed that enables the variation and optimization of different parameters, which were validated by in vitro experiments using a constructed rapid-prototyped human nose model.

RESULTS

For various flow rates (5 to 40 l/min) and particle sizes (1 to 10 μm), the airflow velocities, the calculated particle airflow patterns and the particle deposition correlated very well with the experiment. Particle deposition was investigated numerically by varying particle sizes at constant flow rate and vice versa assuming the particle size distribution of the used nebulizer.

CONCLUSIONS

The developed CFPD model could be directly translated to the in vitro results. Hence, it can be applied for parameter screening and will contribute to the improvement of aerosol particle deposition at the olfactory cleft for CNS drug delivery in particular for biopharmaceuticals.

Olfactory cocainization is not an effective long-term treatment for phantosmia

Phantosmia, the perception of an odor when there are no odorants in the environment, can be a very debilitating symptom. In the 1960s, Zilstorff reported olfactory distortions could be treated by the topical application of a cocaine solution to the olfactory epithelium. In evaluating this treatment, we observed no long-term benefit using cocaine on 6 patients with phantosmia. Based on our observations, the patient's olfactory ability was not a determining factor in the initiation or quality of their phantosmia. Following topical cocainization, we observed a remarkable delay of hours to days in the return of olfactory ability, and when cocaine was applied to only 1 nostril, there was a decreased olfactory ability on the noncocainized side. These results may suggest the possibility that phantosmia is related to a central processing problem.