Histopathologic characteristics of inferior turbinate vs ethmoidal polypin chronic rhinosinusitis

A study on the association between the inferior nasal turbinate volume and the maxillary sinus mucosal lining using cone beam tomography

Objectives

The volume of the inferior turbinates (IT) and the lining of the maxillary sinuses are important parameters when assessing sino-nasal diseases. However, no radiographic studies have investigated the correlation between these parameters. The present study was conducted to analyze the association between IT volumes and thickness of maxillary sinus mucosal lining.

Materials and methods

A retrospective evaluation of the cone-beam computed tomography (CBCT) scans of 100 adult subjects was carried out by two radiologists. The scans were assigned to two groups (Group 1 & 2) based on the radiographic evidence of maxillary sinus lining in the CBCT scans. Group 1 consisted of 50 CBCT scans of subjects with no evidence of maxillary sinus mucosal lining, whereas Group 2 consisted of 50 subjects with evidence of maxillary sinus mucosal lining. The scans in the Group 2 were further sub-classified into five categories, based on the thickness of the maxillary sinus mucosal lining. Vesalius 3D software was used to evaluate the total volume of inferior nasal turbinates by the two radiologists and a mean volume was obtained for each study subject.

Results

The intraclass correlation coefficient (ICC) between the volumetric estimations performed by the two radiologist was 0.87. Analysis of the results revealed that there was no significant gender-based difference (Group 1, P = 0.67 and Group 2, P = 0.95) in the total turbinate volume in either of the study groups. The total turbinate volume did not show any significant correlation (Group 1, r = 0.24 and Group 2, r = 0.12) with the age. There was a significant increase (P = 0.001) in the total turbinate volume of the subjects in Group 2 compared to Group 1. Regression analysis revealed that the thickness of sinus lining correlated significantly (P = 0.001) with the total turbinate volume.

Conclusion

An increase in the total turbinate volume has been associated with an increase in the thickness of the maxillary sinus mucosal lining. The data from this study will be useful for post-operative follow-up of inferior turbinates and maxillary sinus lining after the turbinate volume reduction procedures.

Role of inferior turbinate reduction in the quality of life of patients undergoing endoscopic sinus surgery for chronic rhinosinusitis

BACKGROUND

The impact on quality of life (QoL) of bilateral inferior turbinate reduction (BITR) performed in the setting of endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS) has been a point of controversy. The aim of this study was to determine whether addition of BITR to ESS is associated with improved QoL when compared with ESS alone.

METHODS

This study presented findings a multi-institutional, retrospective analysis of a prospective open cohort of patients electing ESS for failed medical management of CRS. QoL parameters were compared between patients who underwent ESS alone vs those who underwent ESS with BITR.

RESULTS

A total of 571 patients with CRS who elected to undergo ESS were identified. Sixty-one of these patients also underwent concurrent BITR, whereas 510 patients underwent ESS without BITR. Mean length of follow-up was 15.1 months. Comparison between baseline and last postoperative QoL, olfaction, and endoscopic scores revealed significant improvement in both groups. Overall, BITR surgery was not significantly associated with clinically significant incremental improvement in QoL in either the polyp or non-polyp group. Nevertheless, statistically significant improvement was noted for the nasal congestion/blockage symptom in polyp patients (p = 0.006) and in primary surgery patients (p = 0.027) who underwent BITR.

CONCLUSION

BITR in the setting of ESS for CRS is not associated with significant incremental improvement in overall QoL vs ESS alone. However, BITR in polyp and primary surgery patients undergoing ESS appears to offer a significant incremental improvement in nasal congestion/blockage symptoms compared with ESS alone. Future studies are warranted to better corroborate these findings.

Polypoid change of middle turbinate is associated to an increased risk of polyp recurrence after surgery in patients with chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) affects approximately 4% of general population. Patients with CRSwNP have greater burden of CRS symptoms and higher rate of relapse after either medical or surgical treatments. The aim of this study was to evaluate the association between polypoid change of anterior free border of middle turbinate and rate of relapse in patients with CRSwNP.

METHODS

A controlled prospective cohort study was performed. Seventy-seven adult patients with CRSwNP in whom their MT polypoid change was proved and 77 patients without MT polypoid change were recruited. Allergy, asthma, aspirin hypersensitivity, Lund Kennedy and Lund Mackay scores and eosinophilic scores of polyp and middle turbinate were recorded. Patient's health-related quality of life was assessed using the 22-item Sino-Nasal Outcome Test (SNOT-22) questionnaire. All patients were evaluated 12 months after ESS. Polyp relapse, Lund Kennedy scores and SNOT-22 scores were documented.

RESULTS

The relapse rate in patients with MT polypoid change was significantly higher than the control group (37.14 vs. 20.58, p value = 0.03). Eosinophil score of nasal polyps and MT specimens were significantly higher in patients with MT polypoid change than patients without polypoid change. The postoperative Lund Kennedy and SNOT-22 scores in patients with MT polypoid change were significantly higher than the control group.

CONCLUSION

This study showed a significant association between polypoid change of anterior free border of middle turbinate and nasal polyp relapse. This new and simple criterion of severity of CRSwNP could have clinical implications.

Aquaporin expression profiles in normal sinonasal mucosa and chronic rhinosinusitis

BACKGROUND

Thickened secretions, mucosal edema, and polyp formation are pathological features in chronic rhinosinusitis (CRS) that could theoretically be caused by aberrant water flow through sinonasal mucosa. Aquaporins (AQPs) are a family of proteins with roles in water transport, with tissue-specific expression profiles. This study aims to determine if AQP expression in sinonasal mucosa is different between normal controls and patients with CRS, either with (CRSwNP) or without (CRSsNP) nasal polyps.

METHODS

During endoscopic sinus surgery or transsphenoidal surgery, sinonasal tissue was collected and classified as CRSwNP (n = 13), CRSsNP (n = 10), or normal (n = 10). Messenger RNA (mRNA) expression of human AQP0 to AQP12b was determined using quantitative real-time polymerase chain reaction (qRT-PCR). Cellular localization of AQP1, AQP3, AQP4, AQP5, AQP7, and AQP11 was determined by immunohistochemistry.

RESULTS

mRNA of AQP0 to AQP11 was identified in all samples. AQP12b mRNA was not detected. Significant differences in the mRNA expression levels of AQP4 and AQP11 were identified between normal and CRSwNP patients (p < 0.05). Differences in the cellular localization of AQPs were observed in both CRSsNP and CRSwNP patients vs normal controls. More intense localization to the cell cytoplasm was observed for AQP5 in glandular epithelium (CRSwNP; p < 0.05) and surface epithelium (CRSsNP; p < 0.05), and AQP4 in glandular epithelium (CRSsNP; p < 0.05).

CONCLUSION

This study characterized AQP mRNA expression and protein localization in normal human sinonasal tissue. Significant differences in mRNA expression were found for AQP4 and AQP11 in CRSwNP and differences in protein localization patterns of AQP4 and AQP5 were identified in both types of CRS.

Confounding factors in rhinological research

PURPOSE OF REVIEW

Basic science studies directed at understanding the inflammatory mechanisms in chronic rhinosinusitis (CRS) are increasing, yet their relevance to the underlying disease process is often conflicting and confounded by the enrollment of a heterogeneous CRS population. This review is aimed at exploring the issues affecting the basic science mucosal studies of CRS patients, with special attention to the inclusion criteria for CRS and the control group, and the site from which the mucosal tissue sample is obtained.

RECENT FINDINGS

A common confounding factor is an inadequate documentation of selection criteria for patients, controls, and tissue sites examined. Inconsistent definitions for CRS and for maximum medical therapy, and a lack of histopathology confirmation of mucosal inflammation (eosinophilic or neutrophilic) can bias the disease population entering a given study. Further confounding factors include the influence of coexisting diseases, pollution and cigarette smoke, and a need for same-site tissue comparisons, meticulous selection of relevant controls, and consensus on 'nondiseased' mucosal inflammatory cell populations and microbiology.

SUMMARY

Documentation of well defined patient and control groups, standardized specimen collection methods, and detection assays are critical in minimizing the bias and conflicting findings among investigators. With standardized sampling of tissue sites and tight controls on subcategories of CRS patients enrolled, studies will more likely identify the findings that can increase our understanding of the disparate group of CRS patients and identify new therapeutic targets in the CRS subcategories.

A global analysis of tandem 3'UTRs in eosinophilic chronic rhinosinusitis with nasal polyps

Background

Alternative polyadenylation (APA) is emerging as a widespread mechanism of gene regulation. The usage of APA sites allows a single gene to encode multiple mRNA transcripts with different 3′-untranslated region (3′UTR) lengths. Many disease processes reflect the importance of the regulation of APA site switching. The objective of this study was to explore the profiling of tandem APA sites in nasal polyps compared with nasal uncinate process mucosa.

Methods

Sequencing of APA sites (SAPAS) based on second-generation sequencing technology was undertaken to investigate the use of tandem APA sites and identify gene expression patterns in samples from the nasal polyps and nasal uncinate process mucosa of two patients with chronic rhinosinusitis with nasal polyps. The findings of the SAPAS analysis were validated via quantitative reverse-transcription polymerase chain reaction (qRT-PCR).

Results

First, the results showed a switching of 3′UTR lengths in nasal polyps compared with nasal uncinate process mucosa. From the two patients, 105 genes that were detected in both patients in the nasal polyps were switched to distal poly(A) sites, and 90 such genes were switched to proximal poly(A) sites. Several Gene Ontology terms were enriched in the list of genes with switched APA sites, including transcription regulation, cell cycle, apoptosis, and metabolism. Second, we detected genes that showed differential expression with at least a 3-fold difference between nasal polyp tissue and nasal uncinate process mucosa. Between the two sample types, 627 genes exhibited differential expression. The qRT-PCR results confirmed our SAPAS results.

Conclusion

APA site-switching events of 3′UTRs are prevalent in nasal polyp tissue, and the regulation of gene expression mediated by APA may play an important role in the formation and persistence of nasal polyps. Our results may provide new insights into the possible pathophysiologic processes involved in nasal polyps.