[On the postoperative mucocele of the maxillary sinus and its simulating cases. A clinical treatise].

The postoperative mucocele of the maxillary sinus typically occurs after 11-15 years after the initial Caldwell-Luc operation with the complaints of swollen and painful cheek. Typical signs and symptoms will be divided into two groups, the one which is associated with expansive lesions and the other with pains along the various branches of the maxillary nerve. In the clinical set-ups, cases with the similar signs and symptoms, and yet lacking definite mucoceles, are often encountered. The present treatise will compare 86 definite cases and 27 simulating cases as to the history, signs and symptoms, various modalities of imaging (CT & MRI), and the possible causes leading to simulating cases. The age at onset, gender, affected side, and period after the initial sinus surgery all showed no differences between the two, i.e., definite and simulating cases. Among signs and symptoms, the definite case showed more of swelling-related matters whereas the simulating case more of pain-related except toothache. The past history of surgeries for the mucoceles on the similar sides to the present lesion is more often seen in the simulating case (64.3%) than in the definite case (18.3%). The findings by imagings in the simulating cases are as follows; obliterated sinus (25.0%), healthy, aerated postop. cavity (35.7%), postop. cavity with mucosal thickening (32.1%), and cyst-like aerated cavity (7.1%). The possible causes leading to the simulating cases are as follows; causes unknown (39.3%), recurrent infection in the postop. cavity (28.6%), dental origin (10.7%), atypical neuralgia (10.7%) and the case shortly after the proceeding sinus surgery (within 12 months, 10.7%).(ABSTRACT TRUNCATED AT 250 WORDS)