The effect of endoscopic olfactory cleft polyp removal on olfaction

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.

A new surgical technique to increase airflow in the olfactory cleft: superior turbinate lateralization procedure

BACKGROUND

The olfactory cleft (OC) is the most important anatomical site for the maintenance of olfactory function. Obstruction of airflow in the OC by various conditions, such as inflammation, leads to poor olfactory function. Therefore, it is important to increase OC airflow while performing endoscopic sinus surgery (ESS). However, no technique to increase airflow has yet been established.

METHODS

We designed a superior turbinate lateralization (STL) procedure that displaces the entire ST bone laterally by eliminating the connection between the posterior ST and the anterior wall of the sphenoid sinus. The effect of the STL procedure was investigated in terms of anatomy and olfactory function.

RESULTS

ESS with the STL procedure was performed on seven patients with chronic rhinosinusitis and nasal polyps. The cross-sectional area of the OC at 3 months postoperatively was significantly larger than that before ESS. In addition, the Open Essence test and questionnaires revealed significantly improvements in sense of smell. Airflow in the OC was significantly higher in STL procedure group than in the non-STL procedure group.

CONCLUSION

The STL procedure enlarges the bony framework of the OC, and by increasing OC airflow, facilitates the transport of odorants to the olfactory epithelium, thereby improving olfactory perception.

Olfactory dysfunction in chronic rhinosinusitis: insights into the underlying mechanisms and treatments

INTRODUCTION

Olfactory dysfunction (OD) is a typical symptom of chronic rhinosinusitis (CRS), which adversely affects the patient's quality of life and results in mood depression. Studies investigating the impairment of olfactory epithelium (OE) have indicated that inflammation-induced cell damage and dysfunction in OE plays a vital role in the development of OD. Consequently, glucocorticoids and biologics are beneficial in the management of OD in CRS patients. However, the mechanisms underlying OE impairment in CRS patients have not been fully elucidated.

AREAS COVERED

This review focuses on mechanisms underlying inflammation-induced cell impairment in OE of CRS patients. Additionally, the methods used for detection of olfaction and both currently available and potentially new clinical treatments for OD are reviewed.

EXPERT OPINION

Chronic inflammation in OE impairs not only olfactory sensory neurons but also non-neuronal cells that are responsible for regeneration and support for neurons. The current treatment for OD in CRS is mainly aimed at attenuating and preventing inflammation. Strategies for use of combinations of these therapies may achieve greater efficacy in restoration of the damaged OE and consequently better management of OD.

Central Compartment Atopic Disease and Its Surgical Outcomes: Olfactory Changes and Technical Notes

Background

Central compartment atopic disease (CCAD) is a recent, novel phenotype of chronic rhinosinusitis. Only a few studies have assessed olfactory function in patients with CCAD.

Objectives

We aimed to investigate olfactory function changes after functional endoscopic sinus surgery (FESS) in patients with CCAD and proposed some surgical techniques to enhance the postoperative olfactory outcomes in such patients.

Design

A retrospective cohort study.

Methods

We collected data from 23 patients (8 men and 15 women) with CCAD who underwent FESS performed by a surgeon in Taiwan, between June 2018 and December 2021. The demographic data, olfactory function, and serum and tissue eosinophil percentages of the included patients were analyzed. The Top International Biotech Smell Identification Test (TIBSIT; Top International Biotech, Taipei, Taiwan) was used to assess olfactory function.

Results

Of the 23 patients, most (95%) showed a positive reaction to aeroallergens, and 2 patients (8.7%) had asthma. Ten patients (43.5%) had peripheral eosinophilia, and 9 (39%) had eosinophilic nasal polyps. Moreover, the patients presented with variable olfactory dysfunction; the mean preoperative TIBSIT (pr-TIBSIT) score was 12.8 ± 2.3 (range: 0-43), whereas the mean postoperative TIBSIT (po-TIBSIT) score was 29.2 ± 1.9 (range: 16-44). The po-TIBSIT score was significantly better than the pre-TIBSIT score (paired t test, P < .0001). The improvement in olfactory function was not significantly correlated with the patients' age, serum eosinophil percentages, and nasal polyp eosinophil counts.

Conclusion

Our findings indicate that CCAD is significantly associated with olfactory dysfunction and that FESS can effectively improve olfactory function. To optimize postoperative olfactory outcomes, precise removal of polyps from the olfactory cleft without damaging the neuroepithelium is recommended. Our study provides valuable insights into the management of CCAD patients undergoing FESS and can guide surgical decision-making to achieve optimal olfactory function outcomes.

Correlation of polyp grading scales with patient symptom scores and olfaction in chronic rhinosinusitis: a systematic review and meta-analysis

BACKGROUND

Various nasal polyp (NP) scoring systems have been proposed and used in the literature. However, no single system has been identified as superior. Correlations between NP scoring systems and patient symptoms, quality of life (QOL) or olfaction vary widely.

METHODS

A systematic search of PubMed, CINAHL, Scopus, and Cochrane Library was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Any study examining endoscopy scores and symptom, QOL or olfaction measures in cross sectional manner or after therapeutic intervention were included.

RESULTS

This review identified 55 studies for a pooled meta-analysis of Lund-Kennedy (LK-NP) polyp scores (N = 6), Meltzer scores (N = 6), Nasal polyp scores (NPS; N = 19), Total polyp score (TPS; N=8) Lilholdt scores (N = 8), Olfactory cleft endoscopy score (OCES; N =4), Discharge, inflammation, polyp/edema score (DIP; N = 2), and Perioperative sinus endoscopy score (POSE; N = 2). Meta-regression assessed correlations between NP grading systems and SNOT-22, nasal congestion scores, total nasal symptom scores (TNSS), and Smell Identification Test-40 (SIT40). None of the NP grading systems correlated significantly with any symptom, QOL or olfactory metric. In intervention studies of surgery or monoclonal antibody treatment, changes in NPS scores did not correlate with any patient reported outcome measure (PROM) or olfactory outcomes.

CONCLUSION

Current NP endoscopic scoring systems are not associated with PROMs such as SNOT-22, nasal congestion scores, and TNSS as well as objective measures of olfaction. NP grading systems with improved clinical utility are needed.

International consensus statement on allergy and rhinology: Olfaction

BACKGROUND

The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O).

METHODS

Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus.

RESULTS

The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies.

CONCLUSION

This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.

Olfaction: Sensitive indicator of inflammatory burden in chronic rhinosinusitis

BACKGROUND AND OBJECTIVE

Olfactory dysfunction has a high prevalence in chronic rhinosinusitis (CRS) patients and significantly affects quality of life. CRS is recognized as a complex disorder encompassing heterogeneous inflammatory processes in the nose and paranasal sinuses. Olfactory dysfunction in CRS patients is associated with the level of inflammatory mediators and the efficiency of inflammatory control. Learning about the association between CRS-related inflammation and olfactory function will provide clues to the pathogenesis of CRS.

STRUCTURE

The first section of this review describes the assessment of olfactory function using various measures, from ratings to MR based imaging. Then, we discuss the conductive and inflammatory mechanisms related to olfactory dysfunction in CRS: olfaction is associated with certain inflammatory patterns and is potentially a marker of CRS subtype. Finally, we review anti-inflammatory therapies including conservative and surgical approaches, and their effectiveness in olfactory dysfunction in CRS.

CONCLUSION

Assessment of olfactory function should be considered in the clinical evaluation of CRS patients, not only for detecting and quantifying patients' symptom, but also because it appears to be useful to objectively assess the efficacy of CRS treatment over time. In addition, olfaction can be expected to expand the library of CRS phenotypes and endotypes and, hence, pave the way for more precise, tailored treatment options.

Olfactory changes after endoscopic sinus surgery for chronic rhinosinusitis: A meta-analysis

BACKGROUND

Endoscopic sinus surgery (ESS) is an important treatment modality for chronic rhinosinusitis (CRS). However, its effect on olfaction remains controversial.

OBJECTIVE OF REVIEW

To assess the olfactory impact of ESS in patients with CRS.

TYPE OF REVIEW

A meta-analysis.

SEARCH STRATEGY

A systematic literature search in the PubMed, EMBASE and Cochrane Library databases was conducted to identify studies that assessed change in olfaction after ESS in patients with CRS. Search terms were related to paranasal sinus diseases, smell and endoscopy.

EVALUATION METHOD

The extracted data included authors, publication year, study type, age, sex, diagnostic criteria, surgical mode, sample size, follow-up time, olfaction measurement tool and outcome. We analysed the olfactory changes as continuous variables.

RESULTS

Thirty-five studies including 3164 patients with CRS were eligible for the meta-analysis. Among patients having CRS with nasal polyps, olfactory dysfunction improved, as assessed by the Sniffin' Sticks total score (P = .000), Sniffin' Sticks discrimination score (P = .023), Sniffin' Sticks identification score (P = .005), University of Pennsylvania Smell Identification Test (P = .046) and Visual Analogue Scale (P = .000). However, the threshold score of the Sniffin' Sticks test did not improve significantly (P = .361). Olfactory dysfunction did not improve in patients having CRS without nasal polyps according to the University of Pennsylvania Smell Identification Test (P = .404). In non-classified CRS patients, improvement in olfactory dysfunction was observed according to the University of Pennsylvania Smell Identification Test (P = .000), Visual Analogue Scale (P = .001) and Questionnaire of Olfactory Disorders-Negative Statements (P = .001). However, there were no significant improvements according to the Brief Smell Identification Test (P = .325), Sniffin' Sticks threshold score (P = .160) and Sniffin' Sticks identification score (P = .079).

CONCLUSION

Endoscopic sinus surgery may be beneficial for improvement in olfactory conditions in patients with CRS. Further thorough and comprehensive studies need to be conducted.

The Effect of Endoscopic Olfactory Cleft Opening on Obstructed Olfactory Cleft Disease

Purpose

This study was conducted to evaluate the effect of endoscopic olfactory cleft (OC) opening on olfaction in patients with obstructed OC disease. Materials and Methods. Patients with obstructed OC disease who underwent endoscopic OC opening for treatment were enrolled. The endoscopic olfactory cleft opening was performed under local anesthesia. Under an endoscopy, the middle and superior turbinates were gently lateralized to open the OC using an elevator. The phenyl ethyl alcohol threshold test was performed to evaluate the olfactory function both before and after surgery.

Results

An endoscopic OC opening was performed on 42 patients. Amongst them, the etiology of OC obstruction revealed anatomic anomalies in 14 patients, inflammatory process in 14, and anatomic anomalies as well as inflammatory process in 14. The phenyl ethyl alcohol threshold levels improved in 32 (76.2%) of the patients after surgery. The olfactory function was better improved in patients experiencing OC obstructed by inflammatory process than those by anatomic anomalies.

Conclusions

This study showed that endoscopic OC opening seemed to be effective in treating olfactory dysfunction in patients with obstructed OC disease caused by inflammatory process.

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.

Olfactory epithelium: Cells, clinical disorders, and insights from an adult stem cell niche

Disorders causing a loss of the sense of smell remain a therapeutic challenge. Basic research has, however, greatly expanded our knowledge of the organization and function of the olfactory system. This review describes advances in our understanding of the cellular components of the peripheral olfactory system, specifically the olfactory epithelium in the nose. The article discusses recent findings regarding the mechanisms involved in regeneration and cellular renewal from basal stem cells in the adult olfactory epithelium, considering the strategies involved in embryonic olfactory development and insights from research on other stem cell niches. In the context of clinical conditions causing anosmia, the current view of adult olfactory neurogenesis, tissue homeostasis, and failures in these processes is considered, along with current and future treatment strategies.

Level of Evidence

NA.

Clinical effects of submucosal middle turbinectomy for eosinophilic chronic rhinosinusitis

OBJECTIVE

The preservation or resection of the middle turbinate (MT) during endoscopic sinus surgery (ESS) currently remains a matter of debate. The present study aimed to investigate the effects of submucosal middle turbinectomy (SMT) in ESS for eosinophilic chronic rhinosinusitis (ECRS).

METHODS

The study included 38 ECRS patients (63 sides) who had undergone full-house ESS with SMT and 20 ECRS patients (40 sides) without SMT as a control group. Post-operative middle turbinate lateralization (MTL), synechia formation, and the patency grade of the olfactory cleft (OC) were assessed as the primary outcomes 3 months after surgery. CT scans and the T&T test were performed on the SMT group 3 months after surgery and assessed as secondary outcomes.

RESULTS

MTL and synechia formation rates were slightly higher in the control group than in the SMT group (20% vs. 7.9%, p=0.072, 17.5% vs. 9.5%, p=0.235), although neither reached statistically significance. The mean patency score of OC was significantly better in the SMT group than in the control group (0.5±0.6 vs. 1.3±0.7, <0.001). CT findings and T&T test scores showed good improvements after SMT combined with ESS. No major adverse events occurred due to SMT.

CONCLUSION

We demonstrated the potential advantages of SMT for ECRS patients. This method may avoid physiological functional loss through its preservation of the mucosa and structure of the MT.

Anosmia: Differential diagnosis, evaluation, and management

The ability to scrutinize our surroundings remains heavily dependent on the sense of smell. From the ability to detect dangerous situations such as fires to the recollection of a fond memory triggered by an odor, the advantages of an intact olfactory system cannot be overstated. Outcomes studies have highlighted the profound negative impact of anosmia and parosmia on the overall quality of life. The National Institute on Deafness and Other Communication Disorders estimates that ∼1.4% of the United States population experiences chronic olfactory dysfunction and smell loss. Efforts have focused on improving both the diagnosis of olfactory dysfunction through olfactory testing and improved reporting of treatment outcomes of olfactory training. The purpose of this article was to review the differential diagnosis, workup, and current treatment strategies of anosmia and smell disorders.

Olfactory cleft computed tomography analysis and olfaction in chronic rhinosinusitis

BACKGROUND

Volumetric analysis of the olfactory cleft by using computed tomography has been associated with olfaction in patients with chronic rhinosinusitis (CRS). However, existing studies have not comprehensively measured olfaction, and it thus remains unknown whether correlations differ across specific dimensions of odor perception.

OBJECTIVE

To use comprehensive measures of patient-reported and objective olfaction to evaluate the relationship between volumetric olfactory cleft opacification and olfaction.

METHODS

Olfaction in patients with CRS was evaluated by using "Sniffin' Sticks" tests and a modified version of the Questionnaire of Olfactory Disorders. Olfactory cleft opacification was quantified by using two- and three-dimensional, computerized volumetric analysis. Correlations between olfactory metrics and olfactory cleft opacification were then calculated.

RESULTS

The overall CRS cohort included 26 patients without nasal polyposis (CRSsNP) (68.4%) and 12 patients with nasal polyposis (CRSwNP) (31.6%). Across the entire cohort, total olfactory cleft opacification was 82.8%, with greater opacification in the CRSwNP subgroup compared with CRSsNP (92.3 versus 78.4%, p < 0.001). The percent total volume opacification correlated with the total Sniffin' Sticks score (r = -0.568, p < 0.001) as well as individual threshold, discrimination, and identification scores (p < 0.001 for all). Within the CRSwNP subgroup, threshold (r = -0.616, p = 0.033) and identification (r = -0.647, p = 0.023) remained highly correlated with total volume opacification. In patients with CRSsNP, the threshold correlated with total volume scores (r = -0.457, p = 0.019), with weaker and nonsignificant correlations for discrimination and identification. Correlations between total volume opacification and the Questionnaire of Olfactory Disorders were qualitatively similar to objective olfactory findings in both CRSwNP (r = -0.566, p = 0.070) and CRSsNP (r = -0.310, p = 0.141) subgroups, although neither reached significance. When examined by two-dimensional planes, the percent opacification of the anterior plane had the strongest correlations with objective olfaction.

CONCLUSION

Olfactory cleft opacification correlated with objective measures of olfaction in patients with CRS, which correlated with threshold values in patients with CRSsNP and all dimensions of olfaction in those with CRSwNP.

Olfactory Outcomes after Endoscopic Sinus Surgery for Chronic Rhinosinusitis

Objective

To use combined pre- and postsurgical olfactory outcomes to assess the impact of endoscopic sinus surgery on chronic rhinosinusitis−related olfactory impairment.

Data Sources

CINAHL, Cochrane, OVID, EMBASE, PubMed, and SCOPUS. Each database was searched from inception up to October 2015.

Review Methods

Studies were included that reported subjective or objective olfactory data in chronic rhinosinusitis patients before and after endoscopic sinus surgery.

Results

Thirty-one studies were used in the meta-analysis. Weighted mean differences of olfactory measures demonstrated significant improvement in mixed CRS patients (those with and without polyps) through visual analog scales (−0.83, P = .001), altered taste/smell item on Sinonasal Outcome Test (−1.32, P < .00001), 40-item Smell Identification Test (3.49, P = .0010), and Sniffin’ Sticks identification (0.34, P = .03). Chronic rhinosinusitis mixed patients demonstrated nonsignificant improvements via Sniffin’ Sticks threshold (1.60, P = .16) and Brief Smell Identification Test (0.20, P = .32). When separated, polyp patients and dysosmic patients experienced the highest levels of olfactory improvement. Polyp patients improved by 7.87 ( P = .006) on the 40-item Smell Identification test, 11.54 ( P < .0001) with the Sniffin’ Sticks total score, and 2.57 ( P < .00001) through Sniffin’ Sticks identification. Dysosmic patients improved by 5.75 via the 40-item Smell Identification Test ( P = .0001).

Conclusion

Endoscopic sinus surgery improves nearly all subjective and objective measures of olfaction in chronic rhinosinusitis patients. Patients with nasal polyposis or preoperative olfactory dysfunction improve to a greater degree.

Respiratory Epithelial Adenomatoid Hamartomas: An Increasingly Common Diagnosis in the Setting of Nasal Polyps

Background

Respiratory epithelial adenomatoid hamartomas (REAH) are benign nose neoplasms found in the nasal cavity and sinuses. Symptoms include anosmia, nasal obstruction, facial pressure, and rhinorrhea. Although previously thought to be rare, these tumors are being increasingly recognized on pathology in patients undergoing endoscopic sinus surgery. However, REAH is difficult to diagnose before surgery because it may mimic other entities, such as nasal polyps or inverted papilloma, and is often found incidentally only after surgery.

Objective

The aims of this study were to (1) add an additional case series of REAH to the literature, (2) report unique imaging findings on computed tomography and magnetic resonance imaging, and (3) pool and summarize all available data from existing publications.

Methods

Retrospective chart review from years 2004 to 2015 and a literature review

Results

Twenty-three cases were found in our case series, which included 12 men (52%) and 11 women (48%), with a mean age of 59 years. No cases were found before 2007. Lund-Mackay scores were comparable with those found in chronic rhinosinusitis without nasal polyposis. Imaging consistently demonstrated a discoid-shaped mass at the olfactory cleft. Fifty previous publications were found (4 prospective, 11 retrospective studies, 9 case series, 26 cases reports), which included 660 patients diagnosed with REAH. Pooled data revealed a mean age of 54 years (range, 9–86 years) and a male to female ratio of 3:2.

Conclusion

The results of our study further refined the average age at which REAH diagnosis occurs as 54 years old, although it may occur at any age. There is a clear male-to-female predominance (3:2). In addition, olfactory cleft widening and discoid soft tissue at the olfactory cleft are hallmark radiographic findings. The vast majority of published cases occurred during the past 4 years, which indicated increased recognition of REAH.

Effects of triamcinolone-impregnated nasal dressing on subjective and objective outcomes following endoscopic sinus surgery

The aim of this study was to compare the effects of triamcinolone (TA)- and saline-soaked biodegradable nasal dressing on subjective symptoms, wound healing and improvement of olfactory dysfunction in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP) after undergoing endoscopic sinus surgery (ESS). The study was a prospective, randomized, double-blinded, placebo-controlled study. A total of 80 patients undergoing bilateral ESS for CRSwNP were enrolled and randomly assigned to two groups. Nasal dressing was impregnated with normal saline in the control group, while patients received triamcinolone-impregnated dressing in the TA group. Sino-Nasal Outcome Test 20 (SNOT-20) and Korean Version of the Sniffin' Stick (KVSS) II test were used to assess the patients' condition preoperatively and at postoperative 1 and 3 months. Lund-Kennedy (L-K) and perioperative sinus endoscopy (POSE) scores were assessed on postoperative months 1, 2, and 3. There were significant differences between the control group and the TA group in terms of postoperative L-K scores and POSE scores at 1 and 2 months. The postoperative endoscopic scores were significantly decreased in the TA group compared to the control at 1 month. Olfactory functions were significantly improved at postoperative 3 months (p = 0.0099) compared to the preoperative score in the TA group. Significant improvement in the olfactory functions among anosmic and hyposmic patients at postoperative 1 month (p = 0.0475) and 3 months (p = 0.0019) compared to their preoperative olfactory function score was observed only in the TA group. TA-impregnated dressing had a significant advantage over saline-soaked dressing with regard to postoperative wound healing and improvement of olfactory function.

Pathophysiology of Olfactory Disorders and Potential Treatment Strategies

Olfactory disorders have been regarded in the past with a sense of therapeutic nihilism. However, there have been remarkable advances in chemosensory research over the past several years. The clinical importance of olfactory disorders is well established, and entities such as presbyosmia have gained considerable broad attention. Powerful basic science experimental approaches have revealed aspects of olfactory neuron physiology, olfactory tissue maintenance and regeneration that provide new potential therapeutic targets for certain forms of olfactory dysfunction. Although many recent advances remain in pre-clinical stages, there is considerable reason for optimism regarding future approaches for treatment of patients with olfactory loss.