Computational fluid dynamics as surgical planning tool: a pilot study on middle turbinate resection

Controversies exist regarding the resection or preservation of the middle turbinate (MT) during functional endoscopic sinus surgery. Any MT resection will perturb nasal airflow and may affect the mucociliary dynamics of the osteomeatal complex. Neither rhinometry nor computed tomography (CT) can adequately quantify nasal airflow pattern changes following surgery. This study explores the feasibility of assessing changes in nasal airflow dynamics following partial MT resection using computational fluid dynamics (CFD) techniques. We retrospectively converted the pre- and postoperative CT scans of a patient who underwent isolated partial MT concha bullosa resection into anatomically accurate three-dimensional numerical nasal models. Pre- and postsurgery nasal airflow simulations showed that the partial MT resection resulted in a shift of regional airflow towards the area of MT removal with a resultant decreased airflow velocity, decreased wall shear stress and increased local air pressure. However, the resection did not strongly affect the overall nasal airflow patterns, flow distributions in other areas of the nose, nor the odorant uptake rate to the olfactory cleft mucosa. Moreover, CFD predicted the patient's failure to perceive an improvement in his unilateral nasal obstruction following surgery. Accordingly, CFD techniques can be used to predict changes in nasal airflow dynamics following partial MT resection. However, the functional implications of this analysis await further clinical studies. Nevertheless, such techniques may potentially provide a quantitative evaluation of surgical effectiveness and may prove useful in preoperatively modeling the effects of surgical interventions.

Histopathological evaluation of chronic rhinosinusitis: a critical review

BACKGROUND

Chronic rhinosinusitis (CRS) consists of a constellation of symptoms, including facial pressure/pain, hyposmia, rhinorrhea, and nasal congestion. On histopathological evaluation, the disease can be divided into pathophysiologically distinct subgroups. This study systematically reviews the literature regarding the unique histopathological findings of the various subtypes of CRS to determine the potential diagnostic value of performing tissue analysis of CRS specimens beyond routine hematoxylin and eosin (H&E) staining.

METHODS

A PubMed search was untaken to identify articles that evaluated the histopathological features of CRS. Six hundred fifty-four relevant articles were identified and after application of specific exclusion criteria, 71 articles were further reviewed in detail.

RESULTS

All articles included analysis of tissue samples from in-office biopsies or intraoperative specimens of patients who underwent sinus surgery. CRS was often further divided into subgroups and compared with each other and with a control group. The subgroups included CRS with and without nasal polyps, asthmatic and nonasthmatic patients, and with and without eosinophilia. Distinct inflammatory mediators were found for the different subgroups. Twenty-eight articles evaluated these inflammatory markers for their potential value as prognostic indicators.

CONCLUSION

CRS is a heterogeneous disease based on its histopathological findings. Information that is obtainable from light microscopy, but typically goes unreported, can serve as valuable prognostic indictors. However, routine H&E staining is suboptimal in distinguishing among the various subgroups of CRS. Assessment of specific inflammatory mediators in sinus mucosa specimens may help provide prognostic information and guide more tailored treatment for the individual patient.

Correlation analysis of prognostic and pathological features of patients with chronic sinusitis and nasal polyps following endoscopic surgery

The aim of this study was to evaluate the therapeutic value of pathological indicators to predict the efficacy of endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS) with nasal polyps. A total of 53 patients with CRS with nasal polyps, who had undergone endoscopic surgery at least one year before, were surveyed for their clinical symptoms. Surgical specimen biopsies were consulted and related pathological indicators were measured. The association between the main symptoms of CRS with nasal polyps following ESS and pathological indicators were statistically analyzed. The main symptoms of patients with CRS with nasal polyps following ESS were nasal congestion, thick nasal discharge, rhinorrhea or sneezing. Goblet cells are associated with the symptoms of sneezing and thick nasal discharge, pathological gland formation is associated with dizziness, and the degree of tissue edema is associated with post-nasal discharge (P<0.05). Pathological indicators aid the prediction of the efficacy of nasal ESS in patients with CRS with nasal polyps.

The effects of disclosure of sequential rhinomanometry scores on post-septoplasty subjective scores of nasal obstruction: a randomised controlled trial

OBJECTIVE

  We sought to evaluate the effects of awareness of rhinomanometric results on subjective sensation of nasal breathing in patients after septoplasty.

DESIGN

  Prospective randomised study.

SETTING

  Clinical Hospital Rijeka.

PARTICIPANTS

  A study of 60 patients (45 M, 15 F) who underwent septoplasty was performed at the ENT Clinic, Clinical Hospital Rijeka. The patients were randomised into two groups; group A was shown their rhinomanometry scores at 3 months postoperatively, while group B remained unaware of their rhinomanometry results.

MAIN OUTCOME MEASURE

  The assumption is that in the same settings patients aware of their rhinomanometric results have better performances of their Nasal Obstruction Symptom Evaluation (NOSE) scale and thereby a better quality of life (QOL) after septoplasty.

RESULTS

  The differences in rhinomanometric results and NOSE scale prior and after septoplasty were statistically significant (P < 0.001), all patients achieving better results after the operation. There was no statistically significant difference in resistance (F = 0.004; P = 0.948) and improvement of rhinomanometry results in postoperative measurements (F = 0.110; P = 0.896) between groups A and B. The symptoms measured by the NOSE scale were the same in both groups preoperatively and 1 month after septoplasty (F = 2.906; P = 0.094). Three months postoperatively in group A, the NOSE scale score was lower (M = 11.67; sd = 12.34) than in group B (M = 27.50; sd = 18.04).

CONCLUSIONS

  The results suggest that disclosing information to patients about their post-septoplasty rhinomanometry results may improve subjective nasal breathing, and thus improve their QOL.

Endoscopic sinus surgery in the management of nasal obstruction

Nasal obstruction is the leading symptom observed among patients who have chronic rhinosinusitis (CRS) with or without nasal polyposis. After failure of medical therapy, functional endoscopic sinus surgery (FESS) has emerged as the preferred treatment of CRS. Interestingly, although patient-reported outcomes show unequivocal relief of nasal obstruction after FESS, studies measuring nasal airflow and resistance demonstrate more modest improvements. This article provides an overview of the physiology of nasal airflow sensation, the burden of nasal obstruction in patients who have CRS, and the efficacy of FESS in addressing nasal obstruction in this population. Additionally, advances in airflow modeling that may enable improved preoperative planning for the relief of nasal obstruction after FESS are discussed.

Mucosal eosinophils and l-selectin ligands are associated with invasive and noninvasive sinus surgery outcomes

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by persistent inflammation of the nasal and paranasal mucosa with numerous emigrated leukocytes. L-Selectin on leukocytes and its endothelial glycosylated ligands initiate leukocyte infiltration into inflamed tissues. Endoscopic sinus surgery (ESS) is the major approach for restoring sinus physiology after failure of conservative therapy; however, the effect of enlarging the maxillary sinus ostium is still unknown. Here, we compared two histological markers of local inflammation, the number of mucosal eosinophils, and the expression of endothelial L-selectin ligands, with clinical outcomes after enlarging or saving the maxillary sinus ostium.

METHODS

Twenty-three patients with CRS underwent uncinectomy on one side and additional middle meatal antrostomy on the other side. Maxillary sinus mucosa biopsy specimens from these patients and nine healthy subjects were taken for immunohistochemical evaluations of the number of mucosal eosinophils and endothelial L-Selectin ligands. Also, symptoms and mucociliary clearance were measured.

RESULTS

The postoperative reduction of the endothelial L-Selectin ligands was independent of the operation technique. There was a correlation between postoperative number of mucosal eosinophils and symptom score, which was also independent of the surgical technique. The postoperative decrease of mucosal eosinophils, as well as the correlation of the intraoperative eosinophils with the postoperative symptom score, was found only on antrostomy side.

CONCLUSION

ESS decreases the expression of endothelial L-Selectin ligands, which might lead to decreased eosinophil traffic into maxillary sinus mucosa, putatively more when enlarging the maxillary sinus ostium. Both intra- and postoperative low number of eosinophils seem to be indicators of good subjective recovery.

Symptom-specific outcomes of endoscopic sinus surgery: A systematic review

Background: Although multiple studies have demonstrated that symptoms of chronic rhinosinusitis (CRS) improve after endoscopic sinus surgery (ESS), a systematic large-scale evaluation of specific symptom response has not been performed.

Objective: To analyze the relative effectiveness of surgery in the improvement of individual CRS symptoms.

Study Design: A literature search of MEDLINE, EMBASE, Web of Science, Cochrane databases, and other Web-based sources from January 1, 1980 through June 1, 2008 was performed. Studies of 20 or more adult patients with CRS that used symptom severity scores to analyze at least 3 major CRS criteria (facial pressure, nasal obstruction, postnasal discharge, and hyposmia) or 2 major CRS criteria plus headache were included.

Subjects and Methods: Inclusion criteria were met by 21 of 289 ESS studies reviewed. Meta-analysis was conducted for each symptom separately with the standardized difference between the preoperative and postoperative severity scores as the effect size (ES).

Results: A total of 2070 patients with CRS were studied a mean of 13.9 months after ESS. All symptoms demonstrated improvement compared with their respective preoperative severity scores by an overall ES of 1.19 (95% confidence interval, 0.96 to 1.41; I2 = 81.7%) using the random-effects model. Nasal obstruction (ES, 1.73) improved the most, with facial pain (ES, 1.13) and postnasal discharge (ES, 1.19) demonstrating moderate improvements. Hyposmia (ES, 0.97) and headache (ES, 0.98) improved the least.

Conclusion: The relative improvements in major CRS symptoms and headache after surgery are similar, with the exception of nasal obstruction, which improves most.

Partial middle turbinectomy during endoscopic sinus surgery for extended sinonasal polyposis: short- and mid-term outcomes

CONCLUSIONS

The 23 patients with extensive sinonasal polyposis who had undergone partial resection of the middle turbinate during functional endoscopic sinus surgery (FESS) showed no differences in nasal airway resistance and in postoperative complication rate (1-year follow-up period) in comparison with the 25 patients who had FESS with middle turbinate preservation.

OBJECTIVE

The aim of the study was to investigate the outcomes of partial middle turbinectomy during FESS in patients with sinonasal polyposis.

PATIENTS AND METHODS

A retrospective analysis of 48 consecutive patients who had undergone surgery for extended sinonasal polyposis was performed. Twenty-three patients underwent FESS with middle turbinate head resection; 25 patients underwent FESS with preservation of middle turbinate. We endoscopically scored polyposis extension and evaluated nasal airflow resistance (NAR) preoperatively and postoperatively.

RESULTS

We found an improvement of endoscopic score (high to low grade of polyposis extension) and a statistically significant reduction of NAR after both surgical techniques. There was no statistically significant difference in the mean NAR values before and after the two techniques.

The way the wind blows: implications of modeling nasal airflow

Nasal airflow is important for the many physiological functions of the nose, which include the warming and humidifying of inspired air; the filtration of airborne pollutants; and the sense of smell and nasal pungency. Until recently, airflow properties in the nose could only be understood using qualitative in vitro models of humans or in vivo studies in rodents. Recent advances in constructing three-dimensional geometric models of human nasal passages from CT scans, coupled with computational fluid dynamic modeling, has been a valuable tool for quantifying airflow and transport of gases, heat, particles, and aerosols in the human nose. Additionally, these techniques hold significant promise for evaluating and predicting the impact and successful remediation of a variety of clinical conditions on olfaction and nasal patency and setting guidelines for safe levels of exposure to inhaled materials.

Canine fossa puncture and clearance of the maxillary sinus for the severely diseased maxillary sinus

OBJECTIVES

To assess the impact of canine fossa puncture (CFP) with clearance of the maxillary sinus during endoscopic sinus surgery on the subjective and objective outcomes as defined by quality of life questionnaires, endoscopic findings, endoscopic aspirate for culture and sensitivity, and magnetic resonance imaging (MRI) evaluation.

STUDY DESIGN

Retrospective, cross-sectional study.

METHODS

Twenty-five patients who had undergone canine fossa were compared to 12 patients who had undergone routine endoscopic middle meatal clearance of the maxillary sinus. At an average postoperative time point of 19.9 months, all patients were administered the chronic sinusitis survey (CSS) and a visual analogue scale (VAS). At this visit, patients underwent nasendoscopy, sampling of the ostial region for bacterial and fungal cultures, and MRI of the sinuses.

RESULTS

There were 42 sides for analysis from 25 patients on the study arm; the control arm comprised 12 patients with completely opacified maxillary sinuses and 17 sides for analysis. The CSS symptom subscore was better in the CFP group (Mann-Whitney test, P = .02). The overall VAS score was less in the CFP group (Mann-Whitney test, P = .01), indicating better symptom control. No opacification was evident in 61.9% of patients in the CFP group compared with 11.8% in the control arm (chi, P < .001).

CONCLUSION

CFP is a useful technique to address the severely diseased maxillary sinus and is associated with significantly better symptom control compared with the transnasal middle meatal antrostomy clearance of the maxillary sinus.