Treatment outcome of modified endoscopic assisted sinus surgery for treating maxillary sinus diseases with three dimensional volumetric analysis.

This retrospective study aimed to analyze volumetric changes of the maxillary sinus after modified endoscopic-assisted sinus surgery (MESS) and to assess short-term treatment outcomes. The volumes of the total maxillary sinus, aeration, and sinus pathology were calculated using computed tomography data obtained prior to surgery and six months after surgery. Postoperative radiological improvement was assessed using the Lund-Mackay score. Bone regeneration around the bony window was evaluated during plate removal. A total of 32 patients were evaluated. Compared with before surgery, air and sinus pathology volumes improved significantly (air, increase by 6.0 cm, p < 0.001; sinus pathology, decrease by 6.4 cm, p < 0.001). However, there was no statistically significant change in the total maxillary sinus volume after surgery. The preoperative Lund-Mackay score was 2.9, decreasing to 0.4 six months after surgery (p < 0.001). The only predictors of postoperative aeration rate and Lund-Mackay score were preoperative sinus pathology volume (p = 0.049) and Lund-Mackay score (p = 0.015), respectively. The continuity between the bony window and surrounding sinus wall was restored in all patients. The results of this study suggest that MESS can be a successful, effective, and minimally invasive surgical treatment option for treating maxillary sinus diseases.