Osteitis of the nasal bones is a rare disease; when it occurs, it usually has a known etiology. To the best of our knowledge, idiopathic nasal bone osteitis (NBO) has not been described before. We conducted a study to analyze the behavior of idiopathic NBO and its outcome and to determine a cutoff level for diagnosis using technetium-99m-methylene-diphosphonate (Tc-MDP) bone scanning. This retrospective, controlled analysis involved 9 women (mean age: 44 yr) who had been admitted to an otolaryngology department in Israel with idiopathic NBO over a 5-year period. Clinical evaluation, isotopic evaluation, and computed tomography were done. A lesion-to-nonlesion ratio was calculated between an area of interest on the nasal bone and a reference point (L/R ratio). The same ratio was calculated for a control group of 20 subjects. All the Tc-MDP scans in the study group were suggestive of osteitis. Intravenous antibiotic treatment was effective in all cases. A high degree of accuracy was achieved with cutoff L/R ratios of 2.05 for planar views and 2.34 for single-photon emission computed tomography views.