REVERSIBILITY OF ABNORMAL MUCOCILIARY CLEARANCE IN EXPERIMENTAL CHRONIC SINUSITIS

Normal mucociliary clearance in the paranasal sinuses must be restored to reverse the effects of chronic sinusitis. This study examined effe cts of middle mental antrostomy (MMA) on ciliary beat frequency (CBF), mucociliary transport (MCT) velocity, MCT patterns, and histology of sinus mucosa in rabbits with chronic sinusitis to determine whether ob jective measures of mucociliary function and histology could be revers ed Two groups of rabbits were compared: uninfected (Group A controls, n = 9) and infected (Group B, n = 11). Maxillary sinus ostia were occl uded; 10(8) cfu of Streptococcus pneumoniae were inoculated into sinus es of rabbits in group B, and chronic sinusitis developed. This was co nfirmed by histopathology and culture 6 weeks after infection. Middle meatal antrostomies were performed in the infected group, and sinuses were studied 6 weeks later Control animals (Group A) had mean CBF = 11 .5 Hz (+/-.39 Hz). Animals with chronic sinusitis (Group B) had mean C BF = 8.6 Hz (+/-.24 Hz). This was statistically different from control (P < 0.05). Six weeks following MMA, group B had mean CBF = 12.9 Hz ( +/-.75 Hz). This was not different from control. There were changes in MCT velocity that correlated with the CBF (r = 0.72). Examination of MCT patterns after MMA demonstrated minimal pooling and stagnation, ho wever, small areas of misdirected flow persisted After MMA, there were decreased numbers of inflammatory and goblet cells and increased numb ers of ciliated epithelial cells. This study demonstrated that mucocil iary clearance and histological changes seen in rabbits with chronic s inusitis are reversed by MMA.