Significance of osteomeatal complex obstruction

Introduction: Classic teaching has suggested that disease in the osteomeatal complex (OMC) plays a pivotal role in the establishment of chronic rhinosinusitis (CRS). We sought to test this hypothesis. Methods: Retrospective review of 106 consecutive patients enrolled prospectively into a tertiary allergy and sinus center database, meeting the Task Force definition of CRS. Results: Patients were stratified into 3 groups: no OMC obstruction (NOMC, n=38), unilateral OMC obstruction (UOMC, n=24), bilateral OMC obstruction (BOMC, n=44). The mean overall Lund-Mackay score for each of these groups was 3.6, 8.3, and 16.3 respectively (p<0.0001). BOMC patients were significantly more likely to have asthma than those with UOMC or NOMC (52%, 17%, 16%, respectively; p<0.0001). Nasal polyposis was also more frequently observed in the setting of BOMC (59%) compared to either UOMC (38%) or NOMC (13%) (p<0.0001). Incidence of atopy was similar between groups. (TABLE 1) The series was stratified by sides with OMC obstruction (wOMC, n=112) and those without OMC obstruction (sOMC, n= 100). Modified Lund-Mackay score was calculated for the sinus cavities on each side, and this was significantly greater in the wOMC group (5.7 v. 2.0, p<0.0001). The incidence of ipsilateral maxillary sinus disease was also significantly greater in wOMC sides (p<0.0001). In sides without OMC obstruction, the adjacent maxillary sinus was clear in 52% of instances. (TABLE 2) Conclusions: In the present series, >40% of patients meeting the Task Force definition of CRS did not manifest OMC obstruction radiologically. When present, OMC obstruction did correlate with presence of asthma and polyps. OMC obstruction was also associated with increased disease burden overall and ipsilaterally.