Effects of Preservation of the Lamina Propria of the Maxillary Sinus Mucosa on Mucosal Regeneration in Experimentally Induced Maxillary Sinusitis with Polyposis in Rabbits / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It remains unclear whether the lamina propria (LP) of the sinus mucosa should be preserved in the management of the paranasal sinuses with severely diseased mucosa. The aim of this study is to evaluate the effects of preservation of the LP of the maxillary sinus (MS) mucosa on mucosal regeneration in maxillary sinusitis with polyposis in rabbits. MATERIALS AND METHODS: Maxillary sinusitis with polyposis was induced in 180 of the 190 MSs in 95 rabbits and, from these, 10 MSs were used as control. After 4 weeks, the ostia were reopened and 180 MSs were divided into 3 groups according to the following different procedures on the MSs; preservation of the whole mucoperiosteum without removal of polyps and polypoid mucosa (group A), complete removal of the whole mucoperiosteum (group B), and preservation of part of the LP and the periosteum with removal of polyps and polypoid mucosal surface (group C). Each of the experimental groups was explored after 0, 2, 4, 6, 8 and 12 weeks, respectively. Changes of mucociliary transport (MCT) speed, ciliary beat frequency (CBF), and inflammation score in histopathology were evaluated. RESULTS: Eight and/or 12 weeks after the procedures, there were significant improvements in MCT speed, CBF and inflammation score of the group C, compared with those of the group A and/or the group B. CONCLUSION: Preservation of the LP and the periosteum with removal of only polyps and polypoid mucosal surface may be more beneficial to mucosal regeneration than preservation or complete removal of the whole mucoperiosteum including polyps and polypoid mucosa in the surgical management of maxillary sinusitis even though the MS mucosa was severely diseased.

Experimentally Induced Polyps in the Rabbit Maxillary Sinuses: Effects of Different Bacterial Infections with or without Mechanical Trauma on Polyp Formation / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Many studies have been made on sinonasal polyps to elucidate their pathogenesis, definition and treatment. However, recently reported animal polyp studies provided only a few comparative results of polyp formation under various conditions. The aim of this study is to develop an animal model of polyps that is more suitable for further polyp studies by semi-quantitatively analyzing the effects of different bacterial infections with or without mechanical trauma to the rabbit maxillary sinus (MS) mucosa on polyp formation. MATERIALS AND METHODS: The natural ostia of the right MSs were occluded in 40 Pasteurella-free New Zealand white rabbits. The left MSs were used as control. All rabbits were divided into four groups according to different manipulations on the right MSs; Streptococcus pneumoniae was inoculated without brushing the mucosa (group A) and with brushing (group B), Pseudomonas aeruginosa was inoculated without brushing (group C) and with brushing (group D). After four weeks, macroscopic polyps and light microscopic polyps and/or polypoid mucosa were semi-quantitatively analyzed. RESULTS: The number of macroscopic polyps per sinus of group A was significantly smaller than those of groups B, C and D. Microscopic examination revealed significantly higher levels of polyps and/or polypoid mucosa in group B than in group A, but significantly lower levels in group B than in groups C and D. CONCLUSION: P. aeruginosa infection of the rabbit MS proved more beneficial to polyp formation than S. pneumoniae infection, regardless of mechanical trauma to the sinus mucosa. However, for the inoculation of MS with S. pneumoniae, it was more beneficial to poly induction if the mucosa was mechanically traumatized.