Experimental acute sinusitis in rabbit. A study of mucosal blood flow

An experimental model of sinusitis in the rabbit was developed, using type 3 pneumococci. The superior parts of the rabbit maxillary sinuses were surgically exposed and the maxillary ostium was unilaterally blocked. The following day a challenge dose of 10(7)-10(9) colony-forming units of Streptococcus pneumoniae, capsular type 3, was injected into the sinus. When the pneumococci used had been subjected to an animal passage, bacteria were recultured after 4 days. Histological examination showed thickening of the mucosa, with dilated venules and infiltration of granulocytes. No bacteria were seen in the mucosa on staining with acridine orange. With use of microspheres 15 micron in diameter labelled with Sn113, the mucosal blood flow was found to be higher than on the control side.