Mechanical disfunction in the mucosal oedema formation of patients with nasal polyps

Abstract

The interstitial hydrostatic pressure showed different behaviour during liquid infusion in nasal mucosa from NP patients when compared with healthy nasal mucosa. This study allows us to cogitate on a new pathophysiological mechanism contributing to the development of the NP.

Nasal Polyposis: More than a Chronic Inflammatory Disorder—A Disease of Mechanical Dysfunction—The São Paulo Position

“…18 Despite the fact that the polypoid nasal mucosa is empirically recognized as a soft tissue, and that the nasal mucosa in chronic sinusitis without nasal polyposis is empirically recognized as a fibrotic tissue, only in 2014 it was confirmed for the first time that the nasal mucosa of patients with NP is more conducive to edema formation through biomechanical dysfunction. 19 This same study demonstrated that not only the polypoid tissue, but the entire nasal mucosa of patients with NP exhibits a form of mechanical dysfunction, and that this dysfunction varies according to the region of the nasal mucosa. Subsequent biomechanical studies have shown that a healthy nasal mucosa also exhibits different mechanical properties depending on the region, which provides further evidence against the use of the lower-turbinate mucosa as a control tissue in studies of middle meatus diseases, such as NP.…”

Fibrotic Tissue and Middle Turbinate Exhibit Similar Mechanical Properties. Is Fibrosis a Solution in Nasal Polyposis?

“…Our finding of higher pressure in the middle turbinate from healthy nasal mucosa than in nasal polypoid tissue corroborates a previous study. 6 The higher IHP found in fibrotic tissue (synechiae) after saline infusion when compared with polypoid nasal mucosa Fig. 2 (A) Comparison of pressure increase in nasal polypoid tissue versus healthy nasal mucosa (middle turbinate), the pressure increase is greater in healthy middle turbinate than in polypoid tissue.…”

“…A 22-gauge needle coupled to a Controlled Disc Stimulation device (CDS, Smith & Nephew, Memphis, TN, USA) was used to inject the controlled volume within the submucosa to measure local pressure. 6 All patients were under general anesthesia, and received no intranasal drugs before the saline injection.…”

“…5 The altered composition of extracellular matrix in NP creates a mechanical dysfunction in the nasal mucosa, which impairs the interstitial hydrostatic response during interstitial extravasation of volume in polypoid tissue. 6 During the inflammatory process the balance between oncotic and hydrostatic pressure [(capillary osmotic pressureinterstitial osmotic pressure) -(hydrostatic interstitial pressurehydrostatic capillary pressure)] is critical to limit edema formation. Given that the nasal polypoid tissue does not increase the interstitial hydrostatic pressure Introduction Nasal polyposis (NP) is a chronic inflammatory condition of the upper airway characterized by overgrowth of nasal mucosa.…”

“…properly, as found in different inflamed tissues, a greater volume is necessary to achieve the balance between the pressures (the polyp requires three times more infusion of saline solution to reach the same interstitial hydrostatic pressure found in healthy middle meatus mucosa). 6 The interstitial hydrostatic pressure response depends on the tissue mechanical properties which in turn are related to the extracellular matrix.…”