Surgeries to correct nasal airway obstruction (NAO) often have less than desirable outcomes, partly due to the absence of an objective tool to select the most appropriate surgical approach for each patient. Computational fluid dynamics (CFD) models can be used to investigate nasal airflow, but variables need to be identified that can detect surgical changes and correlate with patient symptoms. CFD models were constructed from pre- and post-surgery computed tomography scans for 10 NAO patients showing no evidence of nasal cycling. Steady-state inspiratory airflow, nasal resistance, wall shear stress, and heat flux were computed for the main nasal cavity from nostrils to posterior nasal septum both bilaterally and unilaterally. Paired t-tests indicated that all CFD variables were significantly changed by surgery when calculated on the most obstructed side, and that airflow, nasal resistance, and heat flux were significantly changed bilaterally as well. Moderate linear correlations with patient-reported symptoms were found for airflow, heat flux, unilateral allocation of airflow, and unilateral nasal resistance as a fraction of bilateral nasal resistance when calculated on the most obstructed nasal side, suggesting that these variables may be useful for evaluating the efficacy of nasal surgery objectively. Similarity in the strengths of these correlations suggests that patient-reported symptoms may represent a constellation of effects and that these variables should be tracked concurrently during future virtual surgery planning.
Importance-A gold standard objective measure of nasal airway obstruction (NAO) does not currently exist, so patient-reported measures are commonly used, particularly the Nasal Obstruction Symptom Evaluation (NOSE) and the visual analog scale (VAS). However, questions remain regarding how best to utilize these instruments.Objectives-The goal of this study is to systematically review studies on NOSE and VAS scores in NAO patients and compile and standardize the data to (1) define symptomatic and normative values for (a) pre and post-surgical NAO patients, (b) asymptomatic individuals, and (c) the general population, (2) determine if post-surgery scores are comparable to asymptomatic scores, and (3) determine if there is a clinically useful pre-operative and post-operative score change.Evidence Review-A systematic review of the literature was performed through PubMed for studies assessing NOSE and VAS scores in patients with chronic NAO. Strict inclusion criteria were applied to focus on anatomic obstruction only. For statistical analysis, the patients were divided into asymptomatic, pre-and post-surgery NAO, and the general population.Findings-The average NOSE and VAS scores for a patient with NAO were 65 ± 22 and 6.9 ± 2.3 respectively. The average post-surgery NOSE score was 23 ± 20 and VAS score was 2.1 ± 2.2. The average asymptomatic individual NOSE score was 15 ± 17, and VAS score was 2.1 ± 1.6.
Objective To study the effects of nasal deformity on aerosol penetration past the nasal valve (NV) for varying particle sizes using sprays or nebulizers. Study Design Computed mathematical nasal airway model. Setting Department computer lab Subjects and Methods Particle deposition was analyzed using a computational fluid dynamics model of the human nose with leftward septal deviation and compensatory right inferior turbinate hypertrophy. Sprays were simulated for 10µm, 20µm, 50µm, or particle sizes following a Rosin Rammler Particle Size Distribution (10–110µm), at speeds of 1m/s, 3m/s, or 10m/s. Nebulization was simulated for 1µm, 3.2µm, 6.42µm, or 10µm particles. Steady state inspiratory airflow was simulated at 15.7L/min. Results Sprays predicted higher NV penetration on the right side for particle sizes >10µm, with comparable penetration on both sides at 10µm. Nearly 100% deposited in the nasal passages for all spray characteristics. Nebulizer predictions showed nearly 100% of particles <6.42µm and over 50% of 6.42µm bypassing both sides of the nose without depositing. Of the nebulized particles that deposited, penetration was higher on the right at 10µm, with comparable penetration on both sides at 6.42µm. Spray penetration was highest at 10µm, with over 96% penetrating on both sides at 1 and 3m/s. Nebulization penetration was also highest at 10µm (40% on the left, >90% on the right). Conclusion In the presence of a septal deviation, sprays or nebulizers containing 10µm particles may have good penetration beyond the NV. Nebulized particles <10µm are likely to be respirable. Additionally, spray speeds above 3m/s may limit penetration.
Background The effects of increases in maxillary sinus (MS) airflow following functional endoscopic sinus surgery (FESS) are unknown. The goal of this study was to quantify the effects of FESS on airflow into the MS in a cohort of patients with chronic rhinosinusitis, and compare MS flow rate with patient-reported outcome measures. Methods A pilot study was conducted in which preoperative and postoperative computed tomography scans of 4 patients undergoing bilateral or unilateral FESS were used to create 3-dimensional (3D) reconstructions of the nasal airway and paranasal sinuses using Mimics™ (Materialise, Inc.). The size of the maxillary antrostomies post-FESS ranged from 107 to 160 mm2. Computational meshes were generated from the 3D reconstructions, and steady-state, laminar, inspiratory airflow was simulated in each mesh using the computational fluid dynamics (CFD) software Fluent™ (ANSYS, Inc.) under physiologic, pressure-driven conditions. Airflow into the MS was estimated from the simulations and was compared preoperatively and postoperatively. In addition, patients completed preoperative and postoperative Rhinosinusitis OutcomeMeasure-31 (RSOM-31) questionnaires and scores were compared with MS airflow rates. Results CFD simulations predicted that average airflow rate into post-FESS MS increased by 18.5 mL/second, and that average flow velocity into the MS more than quadrupled. Simulation results also showed that MS flow rate trended with total RSOM-31 and all domain scores. Conclusion CFD simulations showed that the healed maxillary antrostomy after FESS can greatly enhance airflow into the MS. Our pilot study suggests that to some extent, increasing airflow into the MS may potentially improve chronic rhinosinusitis patients’ quality of life pre-FESS and post-FESS.
Otolaryngology-Head and Neck Surgery 147(2S) ORAL PRESENTATIONS changed mentors. Overall, 82% of participants endorsed continuing the program. Conclusion: Mentorship programs are an effective tool in facilitating resident development. Residents would prefer choosing their own mentor and value honesty and supportiveness. Topics relating to private practice and contract negotiations were the areas of greatest discomfort for residents and the least frequently discussed. This represents an area for improvement.
Objective To use computational fluid dynamics (CFD) technology to help providers understand 1) how septal perforations may alter nasal physiology and 2) how these alterations are influenced by perforation size and location. Study Design Computer simulation study Setting Facial Plastic and Reconstructive Surgery clinic Subjects and Methods With the aid of medical imaging and modeling software, septal perforations of 1 and 2 cm in anterior, posterior, and superior locations were virtually created in a nasal cavity digital model. CFD techniques were used to analyze airflow, nasal resistance, air conditioning, and wall shear stress. Results Bilateral nasal resistance was not significantly altered by a septal perforation. Airflow allocation changed, with more air flowing through the lower-resistance nasal cavity. This effect was greater for anterior and posterior perforations than for the superior location. At the perforation sites, there was less localized heat and moisture flux and wall shear stress in superior perforations compared to those in anterior or posterior locations. For anterior perforations, a larger size produced higher wall shear and velocity, while in posterior perforations a smaller size produced higher wall shear and velocity. Conclusions Septal perforations may alter nasal physiology. In the subject studied, airflow allocation to each side was changed as air was shunted through the perforation to the lower-resistance nasal cavity. Anterior and posterior perforations caused larger effects than those in a superior location. Increasing the size of anterior perforations and decreasing the size of posterior perforations enhanced alterations in wall shear and velocity at the perforation.
Background Quantitative methods for comparing intranasal drug delivery efficiencies pre- and postoperatively have not been fully utilized. The objective of this study is to use computational fluid dynamics techniques to evaluate aqueous nasal spray penetration efficiencies before and after surgical correction of intranasal anatomic deformities. Methods Ten three-dimensional models of the nasal cavities were created from pre- and postoperative computed tomography scans in five subjects. Spray simulations were conducted using a particle size distribution ranging from 10–110μm, a spray speed of 3m/s, plume angle of 68°, and with steady state, resting inspiratory airflow present. Two different nozzle positions were compared. Statistical analysis was conducted using Student T-test for matched pairs. Results On the obstructed side, posterior particle deposition after surgery increased by 118% and was statistically significant (p-value=0.036), while anterior particle deposition decreased by 13% and was also statistically significant (p-value=0.020). The fraction of particles that by-passed the airways either pre- or post-operatively was less than 5%. Posterior particle deposition differences between obstructed and contralateral sides of the airways were 113% and 30% for pre- and post-surgery, respectively. Results showed that nozzle positions can influence spray delivery. Conclusions Simulations predicted that surgical correction of nasal anatomic deformities can improve spray penetration to areas where medications can have greater effect. Particle deposition patterns between both sides of the airways are more evenly distributed after surgery. These findings suggest that correcting anatomic deformities may improve intranasal medication delivery. For enhanced particle penetration, patients with nasal deformities may explore different nozzle positions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.