Paranasal Sinus Anatomic Variations Accompanying Maxillary Sinus Retention Cysts: A Radiological Analysis.

Objective: The risk factors for the development of retention cysts of the maxillary sinuses (RCMs) are not clear, although RCMs are common findings on radiographic images. This study was conducted to evaluate the correlation between RCMs and other nasal-paranasal anomalies and to demonstrate the possible effects of these anomalies on the development of RCMs.

Methods: In the study, paranasal sinus computerized tomography (PNsCT) images from 5166 patients were retrospectively reviewed. Correlations between RCMs and osteomeatal complex obstruction, accessory ostium presence, abnormalities of the middle turbinate, and nasal septal deviation were analyzed in the PNsCT images. The paranasal sinus anomalies on the side of the RCMs were compared to the contralateral side.

Results: A total of 1880 RCMs were detected in 1429 (27.6%) of 5166 patients. At least one nasal-paranasal sinus anomaly was associated with 88.7% of the RCMs. In the descending order, accessory ostium presence, accessory ostium, middle turbinate anomalies, and nasal septal deviation are pathologies that accompany RCMs. When unilateral RCMs were compared with the normal side, significant correlations were observed between RCMs and osteomeatal complex obstruction, accessory ostium, and middle turbinate anomalies (p=0.001, p=0.016, and p=0.03, respectively). RCMs were commonly found on the same side as osteomeatal complex obstruction (p=0.001), middle turbinate anomalies (p=0.001), and accessory ostium (p=0.052).

Conclusions: In this study, the coexistence of osteomeatal complex obstruction, accessory ostium, middle turbinate anomalies, and nasal septum deviation with RCMs was analyzed by investigating PNsCT findings in 5166 patients. The results show that RCMs are associated with pathologies that increase paranasal inflammation, such as osteomeatal complex obstruction, and are good markers for nasal-paranasal sinus anomalies. The presence of incidental RCMs should be a warning sign of nasal-paranasal sinus anomalies.