• Chronic rhinosinusitis;
  • biofilms;
  • osteitis;
  • confocal scanning laser microscopy


Bacterial biofilms (BBF) and osteitis are potential contributors to the local inflammatory load in chronic rhinosinusitis (CRS). This study investigated the relationship between BBF and osteitis status in CRS patients.

Study Design

Prospective cohort study.


Eighty-four CRS patients undergoing endoscopic sinus surgery and 22 control patients were enrolled in this study. Mucosal and bony samples from ethmoid sinus were obtained for confocal scanning laser microscopy and microscopic examination. Biofilm volume (BV), biofilm score (BS), histopathologic bony grade, Global Osteitis Scoring Scale (GOSS) score, and Hounsfield unit (HU) value on computed tomography were recorded. Associations between these parameters describing BBF and osteitis were assessed.


The histopathologic bony grade 2 (0–3) versus 0 (0–3) (P < 0.001), GOSS score 4.5 (0–31) versus 0 (0–26) (P = 0.014) and HU value 431.5 (310–509) versus 354 (288–499) (P < 0.001) in patients with BBF were greater than those without BBF. The bony grade (r = 0.683, P < 0.001 and r = 0.664, P < 0.001), GOSS score (r = 0.314, P = 0.004 and r = 0.312, P = 0.004), and HU value (r = 0.539, P < 0.001 and r = 0.520, P < 0.001) were significantly increased with higher BV and BS.


A total of 84.8% of the bone underlying mucosa with BBF had some form of osteitis in ethmoid sinus, and approximately 46.4% of CRS patients were from a subgroup with both BBF and osteitis. The volume of BBF correlated well with severity of osteitis in CRS patients.

Level of Evidence

3b. Laryngoscope, 124:1071–1077, 2014