Investigation of the abnormal nasal aerodynamics and trigeminal functions among empty nose syndrome patients

Computational Fluid Dynamics and Its Potential Applications for the ENT Clinician

This article is an examination of computational fluid dynamics in the field of otolaryngology, specifically rhinology. The historical development and subsequent application of computational fluid dynamics continues to enhance our understanding of various sinonasal conditions and surgical planning in the field today. This article aims to provide a description of computational fluid dynamics, the methods for its application, and the clinical relevance of its results. Consideration of recent research and data in computational fluid dynamics demonstrates its use in nonhistological disease pathology exploration, accompanied by a large potential for surgical guidance applications. Additionally, this article defines in lay terms the variables analyzed in the computational fluid dynamic process, including velocity, wall shear stress, area, resistance, and heat flux.

Tissue specific stem cell therapy for airway regeneration

Secondary atrophic rhinitis (AR), a consequence of mucosal damage during nasal surgeries, significantly impairs patient quality of life. The lack of effective, lasting treatments underscores the need for alternative therapeutic strategies. A major impediment in advancing research is the scarcity of studies focused on secondary AR. Our study addresses this gap by developing an animal model that closely mirrors the histopathological changes observed in patients with secondary AR. These changes include squamous metaplasia, goblet cell hyperplasia, submucosal fibrosis, and glandular atrophy. Upon administering human nasal turbinate stem cells embedded in collagen type I hydrogel in these models, we observed ciliary regeneration. This finding suggests the potential therapeutic benefit of this approach. Our animal models not only emulate the clinical manifestations of secondary AR but also serve as valuable tools for evaluating the efficacy of cell-based biotechnological interventions.

Computed Tomographic Evaluations in Patients with Empty Nose Syndrome

OBJECTIVE

We aimed to evaluate computed tomography (CT) images of patients with empty nose syndrome (ENS), investigate the impact of reconstruction surgery on sinus inflammation, and identify the optimal airspace diameter after surgery.

METHODS

We conducted a retrospective case series analysis, identifying and enrolling patients with ENS with perioperative CT findings. The clinical characteristics of the participants were collected, and the modified Lund-Mackay (mLM) CT scores were determined. The anterior airspace diameter was evaluated by measuring the distance between the septum and the lateral nasal wall on the coronal plane at the level of the nasolacrimal duct.

RESULTS

Twenty patients with ENS and perioperative CT images were enrolled. The mean total mLM CT score and all subsite scores showed no significant changes after surgery. The Empty Nose Syndrome 6-item Questionnaire (ENS6Q) score, Sino-nasal Outcome Test-25 (SNOT-25) score, sleep symptoms domain, psychological domain, and empty nose symptoms domain were significantly associated with anterior airspace diameter in the regression analysis.

CONCLUSION

There was no significant difference in sinus inflammation between preoperative and postoperative CT evaluations. The anterior airspace diameters were significantly associated with ENS6Q and SNOT-25 scores.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2105-2110, 2024.

Effect of preservation versus resection of turbinate on olfactory function in endoscopic trans-nasal trans-sphenoidal pituitary surgery: a systematic review and meta-analysis

BACKGROUND

Utilizing endoscopes in surgery offers advantages and concerns, including potential nasal function impacts. Hyposmia following Transseptal Transsphenoidal hypophysectomy ranges from 0% to 2.2%. Debates persist about managing the M.T. in endoscopic sinus surgery due to its impact on nasal function. While preservation is recommended for sinonasal health, debates continue, as certain cases require resection. Our meta-analysis aims to compare turbinate resection and preservation effects on olfactory function.

METHODS

We searched five electronic databases to collect all relevant studies. Records were screened for eligibility. Data were extracted from the included studies independently. Our continuous outcomes were pooled as standardized mean difference with 95% CI. Statistical analyses was done by RevMan.

RESULTS

Our meta-analysis included four studies involving 235 patients (81 males). Evaluating changes in olfaction scores, two one-month studies (82 patients) revealed no significant difference between preservation and resection groups (Std.MD = 0.05[-0.39, 0.50], p = 0.81). For three-month assessments (146 patients), SNOT tests indicated no significant difference (Std.MD = 0.21, 95% CI[-0.11, 0.54], p = 0.20). Two studies used other tests on 70 patients at three months, yielding no significant difference (Std.MD = 0.13, 95% CI [-0.35, 0.62], p = 0.59). Two six-month studies (72 patients) similarly found no significant difference (Std.MD = 0.09, 95% CI [-0.39, 0.56], p = 0.72).

CONCLUSION

Our meta-analysis involving 235 patients examined olfaction score changes over various time frames in trans-nasal trans-sphenoidal pituitary surgeries. No significant differences were observed between turbinate preservation and resection groups at one month, three months, or six months post-surgery.

Evaluation of Post-Intervention Outcomes in Patients with Empty Nose Syndrome

OBJECTIVES

To conduct a systematic review and meta-analysis of published articles to assess the impact of inferior turbinate/meatus augmentation in patients diagnosed with empty nose syndrome (ENS).

DATA SOURCES

PubMed, Cochrane database, Embase, Web of Science, SCOPUS, and Google Scholar.

REVIEW METHODS

Six databases were searched to December 2022. We retrieved studies evaluating improvements in refractory ENS-related symptoms based on various patient-reported outcome measures after inferior turbinate/meatus augmentation.

RESULTS

As a result of meta-analysis, Sinonasal Outcome Test, Empty Nose Syndrome 6-Item Questionnaire (ENS6Q), and depression scores were measured at 1 week; 1, 3, and 6 months; and later than 12 months after intervention for patients with ENS. All scores revealed significant symptom improvement. By reference to the minimal clinically important difference of the ENS6Q (6.25), inferior turbinate/meatus augmentation relieved the nasal symptoms of ENS in the long term. Although the improvements in anxiety scores at 1 week (0.4133 [-0.3366; 1.1633], 0.00, I2 = NA) and 1 month (0.4525 [-0.0529; 0.9579], I2 = 0.0%) were not statistically significant, the scores differed significantly at 3 months (0.7351 [0.4143; 1.0559], I2 = 28.4%), 6 months (0.8297 [0.6256; 1.0337], I2 = 37.2%), and longer than 12 months (0.7969 [0.4768; 1.1170], I2 = 0.0%).

CONCLUSION

These data and analysis suggest that performing inferior turbinate/meatus augmentation on ENS patients may improve not only nasal symptom scores but also accompanying psychological problems such as anxiety and depression. Laryngoscope, 134:2005-2011, 2024.

The Serpentine Sign: A Reliable Endoscopic and Radiographic Finding in Empty Nose Syndrome

OBJECTIVE

Empty nose syndrome (ENS) is a relatively uncommon disease that greatly impacts the quality of life and presents diagnostic challenges. We sought to identify objective clinical findings unique to patients with ENS, and in doing so identified compensatory mucosal hypertrophy in an alternating, undulating swelling on endoscopy and coronal computerized tomography (CT) that we have termed the "Serpentine Sign." Here, we investigated whether this radiographic finding is a reliable manifestation in ENS patients.

METHODS

Retrospective review was undertaken to identify ENS patients with past turbinoplasty, an ENS6Q score of at least 11/30, and symptomatic improvement with the cotton placement test. Control patients without complaints of ENS symptoms (ENS6Q < 11) were identified for comparison. ENS and control patients had coronal CT imaging available to evaluate for the Serpentine Sign, as well as ENS6Q scores, and histologic analysis of nasal tissue.

RESULTS

34 ENS and 74 control patients were evaluated for the presence of the Serpentine Sign. Of the 34 patients with ENS, 18 exhibited this radiographic finding on CT imaging (52.9%) compared to 0 of the 74 control patients (p < 0.0001). Further analysis demonstrated that ENS patients with the Serpentine Sign had lower median scores on ENS6Q than ENS patients without (17.5 vs. 22, p = 0.033). Histology revealed disorganized subepithelium rich in seromucinous glands similar to the nasal septum swell body.

CONCLUSION

The "Serpentine Sign" is a unique presentation of hypertrophic change to the nasal septum soft tissue that is specific to ENS patients and may serve as a reliable radiographic and endoscopic finding in diagnosis.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1089-1095, 2024.

How Does Oxymetazoline Change Nasal Aerodynamics and Symptomatology in Patients with Turbinate Hypertrophy?

OBJECTIVES

Oxymetazoline relieves nasal obstructive symptoms via vasoconstriction, however, the changes in nasal structures and aerodynamics that impact symptoms the most remain unclear.

METHODS

This prospective, longitudinal, and single blinded cohort study applied Computational Fluid Dynamic (CFD) modeling based on CT scans at baseline and post-oxymetazoline on 13 consecutive patients with chronic nasal obstruction secondary to inferior turbinate hypertrophy from a tertiary medical center. To account for placebo effect, a sham saline spray was administered with subject blindfolded prior to oxymetazoline, with 30 min rest in between. Nasal Obstruction Symptom Evaluation (NOSE) and unilateral Visual Analogue Scale (VAS) scores of nasal obstructions were collected at baseline, after sham, and 30 min after oxymetazoline.

RESULTS

Both VAS and NOSE scores significantly improved from baseline to post-oxymetazoline (NOSE: 62.3 ± 12.4 to 31.5 ± 22.5, p < 0.01; VAS: 5.27 ± 2.63 to 3.85 ± 2.59, p < 0.05), but not significantly from baseline to post-sham. The anatomical effects of oxymetazoline were observed broadly throughout the entire length of the inferior and middle turbinates (p < 0.05). Among many variables that changed significantly post-oxymetazoline, only decreased nasal resistance (spearman r = 0.4, p < 0.05), increased regional flow rates (r = -0.3 to -0.5, p < 0.05) and mucosal cooling heat flux (r = -0.42, p < 0.01) in the inferior but not middle turbinate regions, and nasal valve Wall Shear Stress (WSS r = -0.43, p < 0.05) strongly correlated with symptom improvement.

CONCLUSION

Oxymetazoline broadly affects the inferior and middle turbinates, however, symptomatic improvement appears to be driven more by global nasal resistance and regional increases in airflow rate, mucosal cooling, and WSS, especially near the head of the inferior turbinate.

LEVEL OF EVIDENCE

3: Well-designed, prospective, single blinded cohort trial. Laryngoscope, 134:1100-1106, 2024.

Computational Rhinology: Unraveling Discrepancies between In Silico and In Vivo Nasal Airflow Assessments for Enhanced Clinical Decision Support

Computational rhinology is a specialized branch of biomechanics leveraging engineering techniques for mathematical modelling and simulation to complement the medical field of rhinology. Computational rhinology has already contributed significantly to advancing our understanding of the nasal function, including airflow patterns, mucosal cooling, particle deposition, and drug delivery, and is foreseen as a crucial element in, e.g., the development of virtual surgery as a clinical, patient-specific decision support tool. The current paper delves into the field of computational rhinology from a nasal airflow perspective, highlighting the use of computational fluid dynamics to enhance diagnostics and treatment of breathing disorders. This paper consists of three distinct parts-an introduction to and review of the field of computational rhinology, a review of the published literature on in vitro and in silico studies of nasal airflow, and the presentation and analysis of previously unpublished high-fidelity CFD simulation data of in silico rhinomanometry. While the two first parts of this paper summarize the current status and challenges in the application of computational tools in rhinology, the last part addresses the gross disagreement commonly observed when comparing in silico and in vivo rhinomanometry results. It is concluded that this discrepancy cannot readily be explained by CFD model deficiencies caused by poor choice of turbulence model, insufficient spatial or temporal resolution, or neglecting transient effects. Hence, alternative explanations such as nasal cavity compliance or drag effects due to nasal hair should be investigated.

Autologous fat injection for empty-nose syndrome

AIMS

Inferior meatus augmentation by injection or implants is one of the treatments for empty-nose syndrome (ENS), but levels of evidence of efficacy are low. We present the technique and evaluate our experience. The primary objective was to analyze changes in Empty Nose Syndrome 6-item Questionnaire (ENS6Q) scores after treating patients with ENS by autologous fat injection. Secondary objectives were the analysis of the evolution of each of the six ENS6Q items and identification of complications. Eleven patients underwent a minimally invasive approach to limit nasal airflow using fat injection between March 2021 and December 2022.

RESULTS

Ten of the 11 patients showed a decrease in overall ENS6Q score (P=0.0058); 6 had a final ENS6Q score<11. Ten were satisfied with the procedure, but remained symptomatic. The procedure did not result in any complications.

CONCLUSION

These encouraging results confirm the data in the literature suggesting that fat injection improves symptomatology in empty nose syndrome. However, like other minimally invasive approaches to limit nasal airflow, it does not eliminate all symptoms. These results need to be confirmed by studies on larger cohorts with longer follow-up, preferably in a multicenter setting.

Unique Measurements of Intranasal Trigeminal Function: A Pilot Study

OBJECTIVE

To investigate novel methods of measuring intranasal trigeminal function and correlate to validated measures of trigeminal function.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary medical center.

METHODS

Forty-one subjects without nasal congestion were assessed. The trigeminal temperature function of the cool/warmth detection threshold and cold/heat pain threshold was measured with the Thermal Sensory Analyzer (TSA) device, as previously validated at buccal mucosa and infraorbital skin. Identical temperature sensory function was assessed at the anterior septum and inferior turbinate. Lateralization of trigeminal odorants eucalyptol, isothiocyanate, and acetic acid was conducted. Visual analog scales (VAS) of trigeminal function were collected.

RESULTS

Extraoral cheek site and oral site thermal measures were moderately correlated, suggesting consistent assessment of trigeminal function. Nearly all intranasal thermal measures correlated between the septum and turbinate (significant correlations [ρ] ranged from .3 to .8). Oral and extraoral cheek sites had modest correlations to intranasal cold and heat pain (ρ = .4-.5). The oral site had modest correlations of cold and heat detection to intranasal sites, with turbinate appearing to have the most correlations. Isothiocyanate lateralization was the most closely correlated to intranasal thermal scores for cold and heat pain. Turbinate thermal measures had weak correlations with trigeminal VAS scores (ρ = .3-.4).

CONCLUSION

Intranasal trigeminal measures of thermal function correlate to validated extraoral and intraoral thermal measures. The turbinate appears to have stronger correlations to the septum than found in the mouth and face. TSA testing might provide a rapid, novel method of intranasal trigeminal function assessment.

Human nasal cartilage: Functional properties and structure-function relationships for the development of tissue engineering design criteria

Nose reconstruction often requires scarce cartilage grafts. Nasal cartilage properties must be determined to serve as design criteria for engineering grafts. Thus, mechanical and biochemical properties were obtained in multiple locations of human nasal septum, upper lateral cartilage (ULC), and lower lateral cartilage (LLC). Within each region, no statistical differences among locations were detected, but anisotropy at some septum locations was noted. In the LLC, the tensile modulus and ultimate tensile strength (UTS) in the inferior-superior direction were statistically greater than in the anterior-posterior direction. Cartilage from all regions exhibited hyperelasticity in tension, but regions varied in degree of hyalinicity (i.e., Col II:Col I ratio). The septum contained the most collagen II and least collagen I and III, making it more hyaline than the ULC and LLC. The septum had a greater aggregate modulus, UTS, and lower total collagen/wet weight (Col/WW) than the ULC and LLC. The ULC had greater tensile modulus, DNA/WW, and lower glycosaminoglycan/WW than the septum and LLC. The ULC had a greater pyridinoline/Col than the septum. Histological staining suggested the presence of chondrons in all regions. In the ULC and LLC, tensile modulus correlated with total collagen content, while aggregate modulus correlated with pyridinoline content and weakly with pentosidine content. However, future studies should be performed to validate these proposed structure-function relationships. This study of human nasal cartilage provides 1) crucial design criteria for nasal cartilage tissue engineering efforts, 2) quantification of major and minor collagen subtypes and crosslinks, and 3) structure-function relationships. Surprisingly, the large mechanical properties found, particularly in the septum, suggests that nasal cartilage may experience higher-than-expected mechanical loads. STATEMENT OF SIGNIFICANCE: While tissue engineering holds promise to generate much-needed cartilage grafts for nasal reconstruction, little is known about nasal cartilage from an engineering perspective. In this study, the mechanical and biochemical properties of the septum, upper lateral cartilage (ULC), and lower lateral cartilage (LLC) were evaluated using cartilage-specific methods. For the first time in this tissue, all major and minor collagens and collagen crosslinks were measured, demonstrating that the septum was more hyaline than the ULC and LLC. Additionally, new structure-function relationships in the ULC and LLC were identified. This study greatly expands upon the quantitative understanding of human nasal cartilage and provides crucial engineering design criteria for much-needed nasal cartilage tissue engineering efforts.

Exploring the influence of nasal vestibule structure on nasal obstruction using CFD and Machine Learning method

Motivated by clinical findings about the nasal vestibule, this study analyzes the aerodynamic characteristics of the nasal vestibule and attempt to determine anatomical features which have a large influence on airflow through a combination of Computational Fluid Dynamics (CFD) and machine learning method. Firstly, the aerodynamic characteristics of the nasal vestibule are detailedly analyzed using the CFD method. Based on CFD simulation results, we divide the nasal vestibule into two types with distinctly different airflow patterns, which is consistent with clinical findings. Secondly, we explore the relationship between anatomical features and aerodynamic characteristics by developing a novel machine learning model which could predict airflow patterns based on several anatomical features. Feature mining is performed to determine the anatomical feature which has the greatest impact on respiratory function. The method is developed and validated on 41 unilateral nasal vestibules from 26 patients with nasal obstruction. The correctness of the CFD analysis and the developed model is verified by comparing them with clinical findings.

Trigeminal Function in Sino-Nasal Health and Disease

The upper airway (nasal passages, paranasal sinuses, pharynx, and glottis) provides the sentinel portion of the human respiratory tract, with the combined senses of olfaction (cranial nerve I) and trigeminal sensation (cranial nerve V) signaling the quality of inspired air. Trigeminal function also complements the sense of taste (in turn mediated by cranial nerves VII, IX and X), and participates in the genesis of taste aversions. The ability of trigeminal stimulation in the upper aero-digestive tract to trigger a variety of respiratory and behavioral reflexes has long been recognized. In this context, the last three decades has seen a proliferation of observations at a molecular level regarding the mechanisms of olfaction, irritation, and gustation. Concurrently, an ever-widening network of physiological interactions between olfaction, taste, and trigeminal function has been uncovered. The objective of this review is to summarize the relatively recent expansion of research in this sub-field of sensory science, and to explore the clinical and therapeutic implications thereof.

Olfactory Function and Olfactory Disorders

The sense of smell is important. This became especially clear to patients with infection-related olfactory loss during the SARS-CoV-2 pandemic. We react, for example, to the body odors of other humans. The sense of smell warns us of danger, and it allows us to perceive flavors when eating and drinking. In essence, this means quality of life. Therefore, anosmia must be taken seriously. Although olfactory receptor neurons are characterized by regenerative capacity, anosmia is relatively common with about 5 % of anosmic people in the general population. Olfactory disorders are classified according to their causes (e. g., infections of the upper respiratory tract, traumatic brain injury, chronic rhinosinusitis, age) with the resulting different therapeutic options and prognoses. Thorough history taking is therefore important. A wide variety of tools are available for diagnosis, ranging from short screening tests and detailed multidimensional test procedures to electrophysiological and imaging methods. Thus, quantitative olfactory disorders are easily assessable and traceable. For qualitative olfactory disorders such as parosmia, however, no objectifying diagnostic procedures are currently available. Therapeutic options for olfactory disorders are limited. Nevertheless, there are effective options consisting of olfactory training as well as various additive drug therapies. The consultation and the competent discussion with the patients are of major importance.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Identifying Residual Psychological Symptoms after Nasal Reconstruction Surgery in Patients with Empty Nose Syndrome

Background: Empty nose syndrome (ENS) is a syndrome of paradoxical nasal obstruction that is thought to be mostly caused by inappropriate turbinate procedures. This study aimed to investigate depression- and anxiety-associated psychological symptoms in patients with ENS before and after surgical reconstruction, and to compare them with those of control subjects. Methods: Patients with ENS were prospectively enrolled. The Sino-Nasal Outcome Test-25 (SNOT-25), Empty Nose Syndrome 6-item questionnaire (ENS6Q), Beck Depression Inventory-II (BDI-II), and Beck Anxiety Inventory (BAI) were used to evaluate the participants before and after reconstruction surgery with submucosal Medpor implantation (Stryker, Kalamazoo, MI), as well as control subjects at enrollment. Results: Forty patients with ENS and forty age- and sex-matched controls were recruited. Patients with ENS experienced significant improvement in SNOT-25, ENS6Q, BDI-II, and BAI scores after surgery, but all were significantly greater than those in the control group. Nine patients with ENS (22.5%) had postoperative residual psychological symptoms. Preoperative BDI-II and BAI scores were significant predictors of postoperative residual psychological symptoms. The optimal cut-off value was BDI-II > 28.5 (sensitivity, 77.8%; specificity, 77.4%) in receiver operating characteristic curve analysis. Conclusions: The nasal and psychological evaluations in patients with ENS significantly improved after nasal reconstruction surgery, but both were significantly greater than those in the control group. Identifying individuals who may experience postoperative residual symptoms and providing a multimodal approach, including surgical reconstruction and psychiatric treatment, are suggested.

Sleep impairment in patients with empty nose syndrome

BACKGROUND

Empty nose syndrome (ENS) is characterized by paradoxical nasal obstruction that usually occurs after turbinate surgery. Patients with ENS may also experience significant psychiatric symptoms and sleep dysfunction, which negatively affect the quality of life of affected subjects. This study aimed to evaluate sleep impairment and sleepiness in patients with ENS.

METHODS

Patients with ENS and control participants were recruited prospectively. The Sino-Nasal Outcome Test-25 (SNOT-25), Empty Nose Syndrome 6-item Questionnaire (ENS6Q), Epworth Sleepiness Scale (EpSS), and modified sleep quality index (MSQI) were used to evaluate the participants before and after nasal surgery.

RESULTS

Forty-eight patients with ENS and forty-eight age- and sex-matched control subjects were enrolled. The SNOT-25, ENS6Q, EpSS, and MSQI scores in the ENS group were all significantly higher than those in the control group before and after surgery. After surgery, ENS patients all exhibited significant improvements in SNOT-25, ENS6Q, EpSS, and MSQI scores. Regression analysis revealed that SNOT-25 score was a significant predictor of EpSS and MSQI in preoperative evaluations. ENS patients experiencing daytime sleepiness suffered from significantly more "dryness of nose" and "suffocation" than those not experiencing daytime sleepiness.

CONCLUSIONS

Patients with ENS experienced significantly impaired sleep quality and sleepiness. Nasal reconstruction surgery improved the sleep quality of ENS patients. The severity of sleep dysfunction is associated with the severity of ENS symptoms. Recognizing individuals with significant sleep impairment and sleepiness and providing appropriate management are critical issues for ENS patients.

Autologous Costal Cartilage Augmentation Technique for Treatment of Empty Nose Syndrome

Empty nose syndrome is a rare complication caused by excessive removal of normal tissues after nose surgery. The main symptoms of empty nose syndrome are paradoxical nasal obstruction, dryness, crust and dyspnea. Medical treatments such as irrigation, humidification, and ointment are not very effective, so surgical treatments to reconstruct the normal nasal cavity using implant materials are often considered. If the implant is not properly inserted, the symptoms persist and the implant must be removed again, resulting in the only donor site complications. Therefore, it is essential to treat the implant well and insert it precisely. Here we describe a surgical procedure to manage implant materials using autologous costal cartilage in the form of block, diced, and crushed cartilage for augmentation technique.

Mental health burden of empty nose syndrome compared to chronic rhinosinusitis and chronic rhinitis

BACKGROUND

Empty nose syndrome (ENS) is characterized by the paradoxical perception of nasal obstruction despite patent sinonasal anatomy after surgery. We investigated the relationship between ENS, and anxiety, depression, obsessive-compulsive disorder, and somatic symptom disorder (SSD) compared to individuals with chronic rhinitis (CR) and chronic rhinosinusitis (CRS).

METHODS

This cross-sectional survey study compared ENS and CR and CRS patients. A total of 116 patients participated: 58 ENS patients from digital support groups, and 58 CRS and CR patients from tertiary rhinology clinics. Study participants completed four validated surveys: (1) Empty Nose Syndrome 6-Item Questionnaire, (2) Rhinosinusitis Disability Index (RSDI), (3) Obsessive Compulsive Inventory - Revised (OCI-R), and (4) PRIME MD Patient Health Questionnaire (PHQ).

RESULTS

ENS patients exhibited a mean RSDI of 78.6, 95% confidence interval [CI] 72.8-84.5, compared to 25.2, 95% CI 18.6-31.8 for CRS/CR patients (p < 0.0001). This difference was seen across all subdomains. Using the PHQ, 53% of ENS patients met diagnostic thresholds for SSD compared to 14% of CRS patients (p < 0.0001). In relation to obsessive compulsive disorder (OCD), 18.37% of ENS patients compared to 8.62% of CRS/CR patients scored above the diagnostic threshold (>21) on the OCI-R questionnaire (p = 0.159).

CONCLUSION

ENS patients had diminished sinonasal quality of life and a higher prevalence of comorbid anxiety and depression, compared to CR and CRS. ENS patients were more likely to exceed thresholds for OCD and SSD compared to controls. Future studies are needed to assess the role of SSD in ENS to help optimize treatment for these complex patients.

IMPACT OF THE NASAL VALVE SHAPE ON THE OLFACTORY FUNCTION AND SUBJECTIVE PERCEPTION OF THE NASAL BREATHING

OBJECTIVE

The aim: To study the impact of the internal nasal valve shape on respiratory and olfactory nose function as well as on quality of life.

PATIENTS AND METHODS

Materials and methods: The study involved 17 volunteers who noted satisfaction of nasal breathing in the absence of changes during endorhinoscopy. The study was con¬ducted in two stages: stage 1 involved assessing initial indicators of quality of life by the SNOT-22 questionnaire, performing active anterior rhinomanometry, and estimating the olfactory function (Sniffin' Sticks); stage 2 consisted in re-assessing the mentioned indicators after changing the shape and lumen of the internal nasal valve. The sodium alginate self-hardening gel was used for simulating the narrowing of the nasal valve. It was applied to the mucous in the upper part of the nasal valve area, obturating the diffuser above the level of attachment of the middle nasal turbinate to a depth of 3-4 mm from nasal vestibule.

RESULTS

Results: Air resistance did not change significantly after partial blockage of the internal nasal valve, although, 16 out of 17 patients showed signs of hyposmia with an average Sniffin' Sticks test score 8.68 ± 0.15.

CONCLUSION

Conclusions: The simulated partial blockage of the internal nasal valve lumen in its upper part in the area of the diffuser does not significantly affect the resistance of the air passing through the nasal passages, but the olfactory function is impaired, which is reflected the quality of life.

Correlation of Nasal Mucosal Temperature and Nasal Patency—A Computational Fluid Dynamics Study

OBJECTIVES

Recent evidence suggests that detection of nasal mucosal temperature, rather than direct airflow detection, is the primary determinant of subjective nasal patency. This study examines the role of nasal mucosal temperature in the perception of nasal patency using in vivo and computational fluid dynamics (CFD) measurements.

METHODS

Healthy adult participants completed Nasal Obstruction Symptom Evaluation (NOSE) and Visual Analogue Scale (VAS) questionnaires. A temperature probe measured nasal mucosal temperature at the vestibule, inferior turbinate, middle turbinate, and nasopharynx bilaterally. Participants underwent a CT scan, used to create a 3D nasal anatomy model to perform CFD analysis of nasal mucosal and inspired air temperature and heat flux along with mucosal surface area where heat flux >50 W/m² (SAHF50).

RESULTS

Eleven participants with a median age of 27 (IQR 24; 48) were recruited. Probe-measured temperature values correlated strongly with CFD-derived values (r = 0.87, p < 0.05). Correlations were seen anteriorly in the vestibule and inferior turbinate regions between nasal mucosal temperature and unilateral VAS (r = 0.42-0.46; p < 0.05), between SAHF50 and unilateral VAS (r = -0.31 to -0.36; p < 0.05) and between nasal mucosal temperature and SAHF50 (r = -0.37 to -0.41; p < 0.05). Subjects with high patency (VAS ≤10) had increased heat flux anteriorly compared with lower patency subjects (VAS >10; p < 0.05).

CONCLUSION

Lower nasal mucosal temperature and higher heat flux within the anterior nasal cavity correlates with a perception of improved unilateral nasal patency in healthy individuals.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:1328-1335, 2023.

Evidence of Nasal Cooling and Sensory Impairments Driving Patient Symptoms With Septal Deviation

OBJECTIVES/HYPOTHESIS

About 260,000 septoplasties are performed annually in the US to address nasal septal deviation (NSD). Yet, we do not consistently understand what aspects of NSD result in symptoms.

STUDY DESIGN

Blinded cohort study.

METHODS

Two fellowship-trained surgeons blindly reviewed computerized tomography (CTs) of 10 confirmed NSD patients mixed with 36 healthy controls. All patients were correctly identified, however, 24/36 controls were falsely identified by both surgeons as patients (33.3% specificity), which were grouped as asymptomatic NSD (aNSD), while the remaining controls as non-NSD (healthy). Acoustic rhinometry, rhinomanometry, individual CT-based computational fluid dynamics and nasal sensory testing were applied to address the puzzling questions of why these aNSD had no symptoms and, more fundamentally, what caused symptoms in sNSD patients.

RESULTS

aNSD reported no nasal symptoms - Nasal Obstruction Symptom Evaluation score (sNSD: 60.50 ± 13.00; aNSD: 5.20 ± 5.41; non-NSD: 6.66 ± 7.17, P < .05); 22-item Sino-Nasal Outcome Test score (sNSD: 32.60 ± 14.13; aNSD: 10.04 ± 10.10; non-NSD: 9.08 ± 12.42, P < .001). No significant differences in measured nasal resistance, minimum cross-sectional area (MCA), degree of septal deviation, and nasal airflow distributions were found between sNSD and aNSD groups. Only three variables differentiate sNSD versus aNSD: anterior averaged heat flux on deviated side, inferior turbinate peak heat flux on non-deviated side, and nasal cool sensitivity measured by menthol lateralization threshold, with no significant differences among these variables found between the two healthy groups (aNSD vs. non-NSD). These variables by themselves or combined can differentiate sNSD from controls with higher specificity than the physicians (ROC area under the curve = 0.84 with 70% sensitivity and 91.6% specificity).

CONCLUSIONS

This study sheds light on the potential mechanisms of NSD symptomatology: distorted nasal cooling due to NSD exacerbated by poorer nasal mucosal sensitivity. It further supports our previous hypothesis that nasal obstruction complaints do not result directly from obstruction, rather from the capacity of our nose to subjectively sense airflow cooling.

LEVEL OF EVIDENCE

3 Laryngoscope, 132:509-517, 2022.

Suicidal thoughts in patients with empty nose syndrome

OBJECTIVES

Patients with empty nose syndrome (ENS) suffer from paradoxical nasal obstruction with a patent objective nasal airway. ENS may result from the excessive surgical reduction of the turbinate tissue. ENS patients also experience significant psychological symptoms such as anxiety and depression. In this study, we aimed to evaluate the prevalence of suicidal thoughts in ENS patients and to characterize these patients for early identification.

STUDY DESIGN

Prospective case series.

METHODS

Patients with ENS were prospectively recruited for this study. The Sino-Nasal Outcome Test-25 (SNOT-25), Empty Nose Syndrome 6-item Questionnaire (ENS6Q), Beck Anxiety Inventory (BAI), and Beck Depression Inventory-II (BDI-II) were used to assess ENS patients before and 6 months after nasal reconstruction surgery.

RESULTS

Sixty-two patients with ENS were enrolled. Suicidal thoughts were identified in 23 ENS patients preoperatively and in four patients postoperatively. ENS patients with suicidal thoughts rated significantly higher in the SNOT-25, ENS6Q, BDI-II, and BAI total scores than those without suicidal thoughts (all P < .05). "Nose feels too open" was the item in ENS6Q that was significantly more severe in ENS patients with suicidal thoughts than those without suicidal thoughts (P < .001).

CONCLUSIONS

Suicidal thoughts are frequently identified in patients with ENS. ENS patients with suicidal thoughts experienced significantly more severe symptoms, impaired quality of life, and psychological burden than those without suicidal thoughts. Recognizing individuals who may carry suicidal thoughts and provide appropriate psychological interventions is critical to prevent tragedy.

LEVEL OF EVIDENCE

4.

Management of the middle turbinate during and after sinus surgery

PURPOSE OF REVIEW

Treatment of the middle turbinate (MT) during and after endoscopic sinus surgery (ESS) has been controversial. Historically, there has been concern that resection of the MT may result in smell loss and frontal sinus stenosis. However, these concerns must be balanced by knowledge that a residual diseased MT may result in surgical failure. This review discusses the current evidence on treatment of the MT during and after ESS.

RECENT FINDINGS

Several review articles have shown the safety of performing MT resection. Studies have not shown increase rates of frontal sinus stenosis, olfactory loss, or empty nose syndrome. However, the benefit of MT resection is highly debated. There have also been many recent advances and technological developments to assist in management of the postoperative MT.

SUMMARY

The literature supports the safety of performing MT resection, however, the benefit of resection over preservation is controversial. New technologies and techniques exist that may aid in preventing postoperative MT lateralization.

3D printed transwell-integrated nose-on-chip model to evaluate effects of air flow-induced mechanical stresses on mucous secretion

While there are many chip models that simulate the air-tissue interface of the respiratory system, only a few represent the upper respiratory system. These chips are restricted to unidirectional flow patterns that are not comparable to the highly dynamic and variable flow patterns found in the native nasal cavity. Here we describe the development of a tunable nose-on-chip device that mimics the air-mucosa interface and is coupled to an air delivery system that simulates natural breathing patterns through the generation of bi-directional air flow. Additionally, we employ computational modeling to demonstrate how the device design can be tuned to replicate desired mechanical characteristics within specific regions of the human nasal cavity. We also demonstrate how to culture human nasal epithelial cell line RPMI 2650 within the lab-on-chip (LOC) device. Lastly, Alcian Blue histological staining was performed to label mucin proteins, which play important roles in mucous secretion. Our results revealed that dynamic flow conditions can increase mucous secretion for RPMI 2650 cells, when compared to no flow, or stationary, conditions.

Turbinate surgery: which rhinitis are most at risk

BACKGROUND AND AIM

Allergic rhinitis (AR) and non-allergic rhinitis (NAR) belong to field of vasomotor rhinitis, characterized by nasal hyper-reactivity. Since AR and NAR are two separate nosological entities, these rhinopaties can coexist in the same patient in up to 15-20% of cases. Overlapped rhinitis (ORs) are associated with intense and persistent symptoms and are often misdiagnosed. Typically, when medical treatment fails, patients undergo turbinate surgery. We evaluated which rhinopaties are most at risk of undergoing turbinate surgery and established the percentage of ORs.  Methods: The study included 120 patients undergoing turbinate surgery for turbinate hypertrophy. Anterior rhinoscopy, nasal endoscopy, nasal cytology, skin prick tests (SPT) and/or specific IgE serum assays (CAP-RAST) were performed preoperative on all patients.

RESULTS

Among patients with indication for turbinate surgery, 75% suffered from AR, whereas 25% of them had NAR. On closer analysis, only 7 (8%) of allergic patients presented a "pure" allergy.  NAR with eosinophils and mast cells (NARESMA) represented the most common type of superimposed rhinitis (62.5%), while NAR with mast cells (NARMA) and with eosinophils (NARES) represented 25% and 12.5% of the superimposed forms, respectively.

CONCLUSION

Most of the patients undergoing turbinate surgery actually have complex forms of rhinitis. The non-allergic component of ORs often causes therapeutic failure. NARESMAs overlapping ARs are at most risk of undergoing turbinate surgery. Correctly framing a rhino-allergological patient is essential in order to guarantee the most adequate treatment. Hence the importance of introducing in clinical practice investigations, including allergy tests and nasal cytology.

Effects of Acute Alcohol Intake on Nasal Patency

BACKGROUND

Acute alcohol intake may influence nasal patency; however, there is lack of objective evidence.

OBJECTIVE

The aim of this study was to evaluate the effects of acute alcohol intake on nasal patency employing both subjective and objective measures.

METHODS

A total of 31 participants were classified into 2 groups of non-heavy drinkers (n = 17) and heavy drinkers (n = 14). Both groups consumed wine in 1 h and were assessed for subjective nasal symptoms and objective nasal patency, using rhinomanometry and acoustic rhinometry, at baseline and at 0.5, 2, and 6 h post-alcohol consumption.

RESULTS

Alcohol consumption significantly increased nasal obstruction from baseline values in both heavy and non-heavy drinking groups. Total nasal volume (TNV) and the minimal cross-sectional area (MCA) were significantly decreased and nasal airway resistance (NAR) significantly increased from baseline values by 2 h post-alcohol consumption for both heavy and non-heavy drinking groups (P < .05). Significant differences were found in TNV, MCA, and NAR between baseline and post-drinking in allergic rhinitis subjects; with no significant differences in MCA and NAR in subjects without allergic rhinitis. Pulse rate (PR) and temperature (T) were elevated, and blood pressure (BP) was decreased after alcohol consumption (P < .05). Blood alcohol concentration (BAC) was not significantly correlated with nasal patency with regard to any subjective or objective measurement.

CONCLUSION

Acute alcohol consumption may impair nasal patency, independent of the amount consumed. Individuals with allergic rhinitis may be more prone to nasal obstruction after alcohol consumption than those without allergic rhinitis.

Empty Nose Syndrome Pathophysiology: A Systematic Review

OBJECTIVE

The pathophysiology of empty nose syndrome (ENS) remains unclear despite significant research. The pathophysiologic mechanism of ENS was systematically reviewed.

DATA SOURCES

MEDLINE and Embase.

REVIEW METHODS

Data were systematically reviewed for studies that provided original data on pathophysiology.

RESULTS

A total of 2476 studies were screened, and 19 met the inclusion criteria: 13 case-control and 6 cross-sectional. Nine pathophysiologic themes were identified.• Demographics: ENS symptoms had no relationship with climatic factors.• Symptomatology: ENS patients demonstrated high symptom severity.• Mental health: Anxiety and depression including hyperventilation were reported in >50% of ENS patients and correlated with ENS symptom severity.• Anatomic features: Structural changes in response to turbinate surgery were similar between ENS and non-ENS patients.• Airflow analysis: Airflow parameters were similar between ENS and non-ENS patients after turbinate surgery. On computational fluid dynamic analysis, differences were found on multiple outcomes.• Diagnostic testing: The menthol detection test was impaired in ENS, and cotton placement in the airway improved ENS symptoms.• Cognitive function: Functional magnetic resonance imaging showed activation in emotional processing area during breathing.• Olfactory function: Subjective impairment was reported in ENS, but quantitative measures were similar to non-ENS patients.• Mucosal physiology/innate immunity: Turbinate histopathology in ENS showed a tissue-remodeling pattern. Nasal nitric oxide level was lower in ENS patients.

CONCLUSION

There is evidence of high comorbid mental health disorders in ENS patients. An abnormal trigeminal-thermoreceptor response may be present in some patients. The influence of altered airflow and the evidence of surgery as the cause for ENS are unclear.

Middle turbinate resection is unlikely to cause empty nose syndrome in first year postoperatively

PURPOSE

Empty nose syndrome (ENS) is characterized by nasal dryness, crusting, and paradoxical nasal obstruction most commonly after inferior turbinate resection. ENS has also been reported to occur after middle turbinate resection (MTR), and concern for causing ENS is a possible reason surgeons preserve the MT during endoscopic sinus surgery (ESS). The objective was to determine whether MTR during ESS led to ENS.

MATERIALS AND METHODS

This was a prospective case series of 95 consecutive patients that underwent bilateral subtotal MTR during ESS with either Draf IIB or Draf III frontal sinusotomies, for chronic rhinosinusitis with or without nasal polyps, and frontal sinus inverted papillomas. Demographic data and postoperative Empty Nose Syndrome 6-item Questionnaire (ENS6Q) scores were obtained. Nasal crusting was also documented on last postoperative nasal endoscopy.

RESULTS

Pathologies included chronic rhinosinusitis with nasal polyps (69), without nasal polyps (12), and inverted papillomas (14). Fifty-six patients underwent subtotal MTRs during ESS with Draf IIB, and 39 with Draf III. Mean follow-up was 19.4 months (range 12-49). Mean postoperative ENS6Q score was 2.1. Only 2.1% had ENS6Q scores ≥ 11, and 6.3% had nasal crusting at last follow-up. None of the patients with ENS6Q scores ≥ 11 had nasal crusting at last follow-up. There were no significant differences in outcomes between ages, genders, surgery types, or pathologies.

CONCLUSIONS

Patients who underwent bilateral subtotal MTR during ESS were unlikely to develop ENS by at least 1 year postoperatively, based on patients rarely experiencing ENS6Q scores ≥ 11 or persistent nasal crusting.

Modelling nasal airflow coefficients: an insight into the nature of airflow

BACKGROUND

There has been considerable discussion and conflicting views regarding the presence of laminar or turbulent flow within the nose. The aim of this study was to investigate how the modelling of variable flow coefficients can assist in the evalua- tion of the characteristics of flow in the resistive segments of the nose.

METHODOLOGY

A comparison was made between the flow coefficient for the nasal valve, obtained from a mathematical model, and resistive flow components such as a Venturi meter and orifice tube. Also, a variable loss coefficient was formulated for the whole (unilateral) nose which, by utilising the intersection of the laminar and turbulent asymptotes, provided an estimation for the critical Reynolds number (Rcrit).

RESULTS

The results show that the flow resistance of the nasal valve is considerably greater than that for both a Venturi meter and an orifice tube implying turbulent or turbulent-like flow for much of nasal inspiration. Regarding the loss coefficient for the whole (unilateral) nose, normal respiration flowrates are displaced well away from the laminar asymptote. The critical Reynolds number was estimated to be 450.

CONCLUSIONS

A novel method of determining the flow characteristics of the nose, particularly the critical Reynolds number, is presented. The analysis indicates a higher degree of turbulence than is assumed from a simple traditional calculation using a hy- draulic diameter and flow through straight tubes. There are implications for computational fluid dynamics (CFD) modelling where either the entire nasal airflow is assumed to be laminar or a low turbulence model implemented.

Inferior meatus augmentation procedure (IMAP) normalizes nasal airflow patterns in empty nose syndrome patients via computational fluid dynamics (CFD) modeling

BACKGROUND

Empty nose syndrome (ENS) is a controversial upper airway disorder most commonly associated with tissue loss from the inferior turbinates. The inferior meatus augmentation procedure (IMAP) has been shown to effectively reduce ENS symptoms in a durable manner, but the precise mechanisms that may govern this symptomatic improvement remain unknown.

METHODS

Five patients with ENS who underwent bilateral IMAP via submucosal costal cartilage implant were assessed. Pre-implant and 6 months post-implant computed tomography (CT) imaging for each ENS patient was analyzed in a blinded fashion using computational fluid dynamics (CFD) modeling to investigate intrapatient changes in airflow parameters.

RESULTS

Following surgery, ENS patients have significantly improved symptoms as indexed by Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) scoring (pre-implant: 14.00 ± 4.06 [mean ± standard deviation]; 95% confidence interval [CI], 10.44 to 17.56; post-implant: 4.8 ± 2.77; 95% CI, 2.37 to 7.23; Cohen's d = 2.64; p = 0.02). Using CFD, a significant shift in nasal airflow patterns was observed, where airflow deviates away from the middle meatus upon hitting the implant (pre-implant: 67.13% ± 11.14%; 95% CI, 60.22% to 74.04%; post-implant: 46.18% ± 12.81%; 95% CI, 38.23% to 54.12%; d = 1.74; p < 0.05) toward the inferior meatus (pre-implant: 30.55% ± 11.29%; 95% CI, 23.55% to 37.55%; post-implant: 42.59% ± 9.60%; 95% CI, 36.63 to 48.54%; d = 1.14; p < 0.05). No significant changes were found in nasal resistance (pre-implant: 0.102 ± 0.015; 95% CI, 0.092 to 0.112 Pa*s/mL; post-implant: 0.105 ± 0.041; 95% CI, 0.081 to 0.130 Pa*s/mL). In addition, the improvement of ENS6Q scoring significantly correlated with percent reduction in aberrant airflow through the middle meatus (R² = 0.60, p = 0.04).

CONCLUSION

This study supports our prior working hypothesis that disordered vectors of nasal airflow congregate in the middle meatus contribute to ENS symptoms, not nasal resistance. Moreover, these data illuminate a paradoxical, but consistent, restoration of nasal airflow to the inferior meatus following the replacement of turbinate tissue volume in the inferior meatus via IMAP surgery, potentially due to the Coandă effect.

Regional Peak Mucosal Cooling Predicts Radiofrequency Treatment Outcomes of Nasal Valve Obstruction

OBJECTIVES/HYPOTHESIS

Low energy radiofrequency may offer effective treatment for narrow or obstructed nasal valve, yet its precise mechanism is not fully understood.

STUDY DESIGN

Prospective, nonrandomized, case series.

METHODS

Twenty prospective patients with internal nasal valve obstruction underwent office-based Vivaer treatment (Aerin Medical, Inc) under local anesthesia. Computational fluid dynamics (CFD) models were constructed based on the pre- and 90 days post-procedure computed tomography (CT) scans to identify salient changes in nasal airflow parameters.

RESULTS

Patients' Nasal Obstruction Symptom Evaluation score (NOSE: pre-treatment 78.89 ± 11.57; post-treatment 31.39 ± 18.30, P = 5e-7) and Visual Analog Scale of nasal obstruction (VAS: pre-treatment 6.01 ± 1.83; post-treatment 3.44 ± 2.11, P = 1e-4) improved significantly at 90 days after the minimally invasive approach. Nasal airway volume in the treatment area increased ~7% 90 days post-treatment (pre-treatment 5.97 ± 1.20, post-treatment 6.38 ± 1.50 cm³ , P = .018), yet there were no statistically significant changes in the measured peak nasal inspiratory flowrate (PNIF, pre-treatment: 60.16 ± 34.49; post-treatment: 72.38 ± 43.66 ml/s; P = .13) and CFD computed nasal resistance (pre-treatment: 0.096 ± 0.065; post-treatment: 0.075 ± 0.026 Pa/(ml/s); P = .063). As validation, PNIF correlated significantly with nasal resistance (r = 0.47, P = .004). Among all the variables, only the peak mucosal cooling posterior to the nasal vestibule significantly correlated with the NOSE at baseline (r = -0.531, P = .023) and with post-treatment improvement (r = 0.659, P = .003).

CONCLUSION

Minimal remodeling of the nasal valve (7% in this study) may have a profound effect on perceived nasal obstruction, despite little effect on nasal resistance, or PNIF. The results corroborated our previous findings that subjective relief of nasal obstruction correlates with regional mucosal cooling rather than nasal resistance or peak flow rate, a potential target for future effective, personalized therapeutic approaches.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E1760-E1769, 2021.

Identifying Treatments for Taste and Smell Disorders: Gaps and Opportunities

The chemical senses of taste and smell play a vital role in conveying information about ourselves and our environment. Tastes and smells can warn against danger and also contribute to the daily enjoyment of food, friends and family, and our surroundings. Over 12% of the US population is estimated to experience taste and smell (chemosensory) dysfunction. Yet, despite this high prevalence, long-term, effective treatments for these disorders have been largely elusive. Clinical successes in other sensory systems, including hearing and vision, have led to new hope for developments in the treatment of chemosensory disorders. To accelerate cures, we convened the "Identifying Treatments for Taste and Smell Disorders" conference, bringing together basic and translational sensory scientists, health care professionals, and patients to identify gaps in our current understanding of chemosensory dysfunction and next steps in a broad-based research strategy. Their suggestions for high-yield next steps were focused in 3 areas: increasing awareness and research capacity (e.g., patient advocacy), developing and enhancing clinical measures of taste and smell, and supporting new avenues of research into cellular and therapeutic approaches (e.g., developing human chemosensory cell lines, stem cells, and gene therapy approaches). These long-term strategies led to specific suggestions for immediate research priorities that focus on expanding our understanding of specific responses of chemosensory cells and developing valuable assays to identify and document cell development, regeneration, and function. Addressing these high-priority areas should accelerate the development of novel and effective treatments for taste and smell disorders.

Impact of Psychologic Burden on Surgical Outcome in Empty Nose Syndrome

OBJECTIVES /HYPOTHESIS

Empty nose syndrome (ENS) is a complicated condition currently thought to be caused by excessive surgical resection of turbinate tissue. Patients with ENS experienced significant psychological symptoms, such as depression and anxiety. This study aimed to evaluate the impact of the psychological burden on the surgical outcome of ENS.

STUDY DESIGN

Prospective case series in a tertiary medical center.

METHODS

Patients with ENS were prospectively recruited between 2015 and 2018. Validated instruments including the Sinonasal Outcome Test-25 (SNOT-25), Beck Depression Inventory-II (BDI-II), and Beck Anxiety Inventory (BAI) were used to evaluate patients with ENS prior to and 3, 6, and 12 months after nasal reconstruction surgery with submucosal Medpor implantation.

RESULTS

A total of 54 ENS patients were enrolled during the study period. All three evaluations revealed significant improvement, and symptoms stabilized 3 months after surgery. Six months post-operatively, SNOT-25 scores were significantly associated with the pre-operative BDI-II and BAI scores (β = 0.64 and 0.87; P = .006 and <.001, respectively). Multivariate regression model revealed that only BAI scores were significantly associated with the six-month post-operative SNOT-25 scores (adjusted β = 0.49, P = .036). Moreover, Spearman's correlation found close relationships between the post-operative SNOT-25 and the post-operative BDI-II and BAI scores (r_s = 0.751 and 0.884, both P < .001).

CONCLUSIONS

Psychological evaluation can help predict surgical outcomes and identify patients with residual disease. These findings emphasize the importance of screening for psychological symptoms and structuring care by including psychological therapy in addition to surgery.

LEVEL OF EVIDENCE

4. Laryngoscope, 131:E694-E701, 2021.

Relationship Between the Bilateral Removal of the Middle Nasal Turbinate and the Olfactory Function in Endoscopic Skull Base Surgery

OBJECTIVE

To determine the impact of endonasal endoscopic access to the skull base on the olfaction sense, involving the harvest of a nasoseptal flap, with the removal of the middle nasal turbinate.

METHODS

A study was performed on a prospective cohort of 50 patients who underwent transnasal endoscopic surgery of the anterior skull base, with the harvest of a nasoseptal and reverse flap. The patients were divided into 2 groups: partial unilateral removal of the middle nasal turbinate and bilateral removal. Connecticut Chemosensory Clinical Research Center tests were administered before surgery and in months 1, 3, and 6 after surgery.

RESULTS

There was no difference in the olfactory sense, when comparing the partial removal of the middle nasal turbinate and the bilateral removal, as well as when comparing the side without the middle nasal turbinate and the side with this structure preserved. There was a worsening in olfaction (P < 0.001) in months 1 and 3 after surgery, returning to baseline in month 6 (P > 0.05).

CONCLUSIONS

Bilateral removal of the middle nasal turbinate, compared with unilateral resection, showed no impact on the olfactory function 6 months after surgery. In both groups, there was a transitory decrease in the first month, but this normalized by the sixth postoperative month.

Prelacrimal approach vs conventional surgery for inverted papilloma in the maxillary sinus

BACKGROUND

The prelacrimal approach, termed endoscopic modified medial maxillectomy (EMMM), has recently been applied for treatment of inverted papilloma (IP) in the maxillary sinus. EMMM provides wider access to the maxillary sinus while preserving the inferior turbinate and nasolacrimal duct.

METHODS

We reviewed patients with IP in the maxillary sinus to compare the surgical results obtained by conventional surgery (ie, endoscopic maxillary sinus antrostomy or in combination with the Caldwell-Luc approach) with those obtained by EMMM.

RESULTS

All patients had a T3 on the Krouse staging system, and the average follow-up time was 46.0 months. Of the 18 patients in the conventional group, recurrence was seen in 3 patients (16.6%). No recurrence was seen in the 27 patients who showed preservation of the inferior turbinate and nasolacrimal duct, and no complications occurred in the EMMM group.

CONCLUSIONS

EMMM is an effective surgical approach that reduces recurrence with fewer complications.

Distinct Histopathology Characteristics in Empty Nose Syndrome

OBJECTIVES/HYPOTHESIS

Empty nose syndrome (ENS) is a controversial disorder and the change of histopathology has never been discussed. This study aimed to conduct a structured histological review to improve the diagnosis and understanding of ENS. Further immunohistochemical staining of transient receptor potential channel melastatin 8 (TRPM8) was performed.

STUDY DESIGN

A prospective case-control study in a tertiary medical center.

METHODS

Consecutive patients with ENS who were diagnosed and received surgical intervention after failure of conservative management were included. Patients with benign pituitary gland tumor receiving transsphenoidal excision were enrolled as control group. Biopsy of inferior turbinate was obtained during surgery for histological review and immunohistochemical staining.

RESULTS

Seventeen patients with ENS and six patients as a control group were established for structured histological review. Patients with ENS presented significantly more squamous metaplasia, a higher rate of submucosal fibrosis, and a lower submucosal gland number grading. Additionally, a unique histological change called goblet cell metaplasia was found in the ENS group. The respiratory epitheliums of ENS were mostly intact with preservation of ciliated cells and goblet cells. The ENS group had a significantly lower expression level of TRPM8.

CONCLUSIONS

The nasal mucosa of ENS experienced some airway remodeling and thermoreceptors downregulation, which contribute to clinical symptoms. The distinct histology of ENS included preserved respiratory epithelium and goblet cell metaplasia, accompanying with characteristics similar to atrophic rhinitis. Biopsy of the inferior turbinate may help diagnose ENS.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E14-E18, 2021.

Management of Postsurgical Empty Nose Syndrome

Empty nose syndrome (ENS) is a controversial condition associated with disruption of nasal airflow caused by excessive loss of turbinate tissue. ENS arises after total or near-total inferior turbinate resection. Patients present with intense fixation on the perception of nasal obstruction. Diagnostic tools to assess for empty nose syndrome include a validated patient questionnaire and the office cotton test. Treatment involves topical moisturization, behavioral/psychiatric assessment/treatment, and surgical reconstruction. Current data show promising long-term efficacy after surgical intervention. Postprocedural ENS is best prevented by minimizing inferior and middle turbinate tissue loss.

The cotton test redistributes nasal airflow in patients with empty nose syndrome

BACKGROUND

Empty nose syndrome (ENS) remains a controversial disease primarily associated with inferior turbinate tissue loss. Cotton placement into the inferior meatus often alleviates ENS symptoms within minutes, but the physiologic explanation for this phenomenon is unknown. Computational fluid dynamics (CFD) was employed to evaluate the mechanisms of altered nasal airflow conferred by cotton testing.

METHODS

Six ENS patients (12 sides) with pre-existing sinus computed tomography (CT) imaging were enrolled after marked symptomatic improvement (decrease in score on the Empty Nose Syndrome 6-Item Questionnaire [ENS6Q] of >7 points) with office-based cotton testing. The fashioned cotton plug was labeled in situ with iohexol contrast spray, and sinus CT was immediately obtained to detect cotton contouring in the inferior meatus. CT imaging from pre- and post-cotton placement was analyzed using comparative CFD techniques.

RESULTS

After cotton placement, significant symptomatic improvement and reduced ENS6Q scores (16.8 ± 4.1 to 3.1 ± 2.4; p < 0.001) were recorded. Using CFD, cotton placement produced an expected 21% increase in upper airway resistance (p < 0.05). However, a significant shift in the nasal airflow distribution was also detected, with a transition of airflow vectors away from a middle meatus jetstream (-41%; p < 0.002).

CONCLUSION

Objective CFD assessment confirmed that the cotton test not only increases nasal resistance, but also restores airflow distribution to the inferior meatus in symptomatic ENS patients. These results highlight the potential efficacy of cotton test in ENS patients and further bolster the utility of this tool in identifying appropriate candidates for the inferior meatus augmentation procedure.

Update on empty nose syndrome: disease mechanisms, diagnostic tools, and treatment strategies

PURPOSE OF REVIEW

To discuss the proposed pathophysiology of empty nose syndrome (ENS), summarize and evaluate the role of validated diagnostic tools in the diagnosis of ENS, and review the medical and surgical treatment strategies for patients with ENS.

RECENT FINDINGS

Historically, ENS has been associated with a reduction in nasal turbinate size; new data suggest that impaired trigeminal nerve function may also play a role in the pathophysiology of the disease. The newly validated empty nose syndrome 6 item questionnaires and Cotton test are steps forward to standardize the diagnosis of ENS. Finally, there has been a marked increase in surgical treatment strategies to reconstitute turbinate volume with various implant materials.

SUMMARY

The diagnosis of ENS remains controversial but the last several years have seen a rejuvenation of interest in this disease entity. The validated empty nose syndrome 6 item questionnaires and Cotton test provide a standardized and objective means by which to characterize ENS. Prevention of iatrogenic ENS through avoidance of excessive turbinate reduction remains critical in preventing paradoxical nasal obstruction. Nasal humidification, patient education, and treatment of possible concomitant medical conditions (e.g., depression) constitute first lines of treatment. We support the cautious use of these screening tools as adjuncts to clinical decision-making. Although injectable implants to augment turbinate volume show promise as a therapeutic surgical technique, there is insufficient data to fully support their use at this time.

Peak Sinus Pressures During Sneezing in Healthy Controls and Post-Skull Base Surgery Patients

OBJECTIVES/HYPOTHESIS

Patients are frequently advised to sneeze with an open mouth and avoid nose-blowing following an endoscopic endonasal approache (EEA) to the skull base, despite a lack of quantitative evidence. This study applies computational fluid dynamics (CFD) to quantify sinus pressures along the skull base during sneezing.

STUDY DESIGN

Case-control series.

METHODS

Computed tomography or magnetic resonance imaging scans of four post-EEA patients and four healthy controls were collected and analyzed utilizing CFD techniques. A pressure drop of 6,000 Pa was applied to the nasopharynx based on values in the literature to simulate expiratory nasal airflow during sneezing. Peak pressures along the skull base in frontal, ethmoid, and sphenoid sinuses were collected.

RESULTS

Significant increases in skull base peak pressure was observed during sneezing, with significant individual variations from 2,185 to 5,685 Pa. Interestingly, healthy controls had significantly higher pressures compared to post-EEA patients (5179.37 ± 198.42 Pa vs. patients 3,347.82 ± 1,472.20 Pa, P < .05), which could be related to higher anterior nasal resistance in unoperated healthy controls (0.44 ± 0.22 vs. 0.31 ± 0.16 Pa/mL/sec for patients, P = .38). The sinus pressure buildup may be due to airway resistance functioning as a valve preventing air from being released quickly. Supporting this theory, there was a strong correlation (r = 0.82) between peak skull base pressure and the ratio of anterior resistance to total resistance. Within-subject variation in pressures between different skull base regions was much lower (average = ~5%).

CONCLUSIONS

This study provided the first quantitative analysis of air pressure along the skull base during sneezing in post-EEA patients through CFD, suggesting that pressure buildup may depend on individual anatomy.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:2138-2143, 2020.

Patient-Reported Outcome Measures and Provocative Testing in the Workup of Empty Nose Syndrome-Advances in Diagnosis: A Systematic Review

Background

The last 5 years have seen a surge of both clinical and scientific interest in empty nose syndrome (ENS). Although ENS is still considered a controversial diagnosis plagued by a lack of standardized diagnostic criteria, ENS is increasingly becoming recognized as a legitimate, physiologic disease entity. As such, it is important for clinicians to understand the most up-to-date diagnostic tools to assess ENS, confirm the diagnosis, and create a more standardized means to counsel these complex patients.

Objective

Contemporary literature review to discuss diagnostic modalities in the evaluation of ENS, in order to introduce evidence-based diagnostic criteria.

Methods

A systematic review was conducted in PubMed and Embase (2013–2019) using the search term “empty nose syndrome” to identify peer-reviewed articles on the topic of ENS. Articles advancing contemporary methods of ENS diagnosis and testing were included. A quality assessment was conducted using The Rational Clinical Examination Levels of Evidence.

Results

The novel development of the Empty Nose Syndrome 6 Questionnaire (ENS6Q) offers the clinician a validated patient-reported outcome measure to supplement history and physical examination. The in-office cotton test, performed by placing an endoscopically directed cotton plug in the site of tissue loss, may help to identify patients who may benefit from turbinate augmentation. Tools such as the sinus computed tomography scan, computational fluid dynamics, and intranasal trigeminal nerve function testing currently have insufficient evidence to support routine use in the workup of ENS. Up to 66% of ENS patients present with comorbid anxiety or depression.

Conclusion

The ENS6Q and cotton test assist in creating a standardized approach to the evaluation of patients suspected of ENS. These instruments should be used as an adjunct, rather than the sole criteria, on which to ascertain the presumptive diagnosis. Patients suspected of ENS should be screened for comorbid psychological dysfunction.

Functional relevance of computational fluid dynamics in the field of nasal obstruction: A literature review

BACKGROUND

Nasal airway obstruction (nasal obstruction) is a common symptom affecting the quality of life of patients. It can be estimated by patient perception or physical measurements. Computational fluid dynamics (CFD) can be used to analyse nasal ventilation modalities. There is a lack of comparative studies investigating the correlations between CFD variables and patient perception or physical measurements.

OBJECTIVE OF THE REVIEW

Our goal was to define correlations between CFD variables and patient perception and physical measurements. We also aimed to identify the most reliable CFD variable (heat flux, WSS, total pressure, temperature…) characterising nasal breathing perception.

TYPE OF REVIEW

Systematic literature review using PRISMA guidelines.

SEARCH STRATEGY

The selected studies were obtained from the US National Library of Medicine (PubMed) online database, MEDLINE (Ovid), Google Scholar and the Cochrane Library using a combination of MeSH terms (nose, paranasal sinus, fluid dynamics, rhinology) and non-MeSH terms (CFD, nasal airway, nasal airflow, numerical, nasal symptoms). Studies that did not incorporate objective or subjective clinical assessment were excluded.

EVALUATION METHOD

We compared all results obtained by authors regarding CFD variables and assessment of nasal airway obstruction (clinical or physical).

RESULTS

To compare nasal obstruction with CFD variables, most authors use CFD-calculated nasal resistances, airflow, heat flux, wall shear stress, total pressure, velocities and streamlines. We found that heat flux appears to be the CFD variable most closely correlated with patient perception. Total pressure, wall shear stress and velocities are also useful and show good correlations. Correlations between CFD-calculated nasal resistances and patient perception are stronger after correction of the nasal cycle.

CONCLUSIONS

The growing number of CFD studies on the nose has led to a better understanding of nasal obstruction. The clinical interpretation of previously unknown data, such as WSS and heat flux, is opening up new horizons in the understanding of this symptom. Heat fluxes are among the best CFD values correlated with patient perception. More studies need to be performed including temperature and humidity exchanges.

Responsiveness of acoustic rhinometry to septorhinoplasty by comparison with rhinomanometry and subjective instruments

OBJECTIVES

Nose patency measures and instruments assessing subjective health are increasingly being used in rhinology. However, there is very little evidence of comparing existing methods' responsiveness to change. We evaluated the responsiveness of acoustic rhinometry to nasal valve surgery by comparison with rhinomanometry and patient-reported outcome instruments.

DESIGN

Prospective case-control study.

SETTING

Tertiary referral University Hospital.

PARTICIPANTS

Sixty consecutive patients with internal nasal valve dysfunction and 20 healthy volunteers as control group were enrolled. Prospectively collected data included acoustic rhinometry, rhinomanometry, NOSE scale, SNOT-23 questionnaire, visual analogue scale and demographics.

MAIN OUTCOME MEASURES

Primary endpoint was the responsiveness of acoustic rhinometry to functional septorhinoplasty surgery at 3 months. Secondary endpoints were ability of acoustic rhinometry to reflect "known group" differences and correlation to subjective symptoms.

RESULTS

Acoustic rhinometry was highly responsive to septorhinoplasty (P < 0.0001) while anterior rhinomanometry was not (P = 0.08). Based on the quartiles of the postoperative change in NOSE score, patients were classified as, respectively, non-responders, mild, moderate and good responders to surgery. Logistic regression model showed that acoustic rhinometry was able to discriminate non-responders to responders to surgery (P = 0.019), while anterior rhinomanometry failed (P = 0.611). Sensitivity and specificity of acoustic rhinometry were significantly higher (ROC area = 0.76) than rhinomanometry (ROC area = 0.48). Acoustic rhinometry was also superior than rhinomanometry to discriminate patients from control subjects and agreed better with patients-based subjective questionnaires.

CONCLUSIONS

Our study confirms and quantifies the responsiveness of acoustic rhinometry to nasal valve surgery, with a higher sensitivity and specificity than rhinomanometry.