Objective: To assess the frequency of the lacrimal recess in the maxillary sinus (MS) in computed tomography (CT) of the paranasal sinuses. Methods: CT of the paranasal sinuses (CT PNS) done in a total of 78 patients. According to the discoveries, the MS were classified in two types: anterior or lateral. Results: 41 CT PNS of 41 patients of a total of 78 patients preselected were excluded. 37 CT of the paranasal sinuses from 37 patients, in a total of 68 maxillary sinuses were studied. In the 33 right maxillary sinuses, 10 lacrimal recesses were found, 9 from male patients. Eleven left maxillary sinuses with lacrimal recess were found from a total of 35 left maxillary sinuses. Conclusion: From the analysis of 68 MS, a frequency of 30.9% of lacrimal recesses in the maxillary sinuses in CT was observed. (C) 2012 Elsevier Ireland Ltd. All rights reserved.825802805