Based on the preliminary results reported previously, we evaluated the clinical usefulness of quantitative analysis of maxillary densities on digitized X-ray images in 288 sites of 144 patients. These patients were selected from among 2500 who visited the Department of Otorhinolaryngology and who were examined for paranasal sinusitis. We accomplished the quantitative analysis using the new value M_1/O without visual evaluations. The results obtained by quantitative analysis will be helpful in the early diagnosis of mild paranasal inflammatory changes as a computer assisted diagnostic tool.
