The diagnostic efficacy of magnetic resonance imaging and ultrasonography in Morton's neuroma: a radiological-surgical correlation.

All patients operated upon for Morton's neuroma during 1991 who were examined with both magnetic resonance imaging and ultrasonography were included in this prospective study. The object of the study was to evaluate the diagnostic value of these two modalities. The preoperative diagnosis was purely clinical. Histology confirmed surgical findings. A 0.3 T scanner was used for the magnetic resonance imaging, and a 7.5 MHz linear transducer was used for the ultrasonography. The study includes nine patients. Eight neuromas were found at surgery. Of these, only five were diagnosed with magnetic resonance imaging and three with ultrasonography. This indicates that false negative diagnoses are common. At present we find these modalities of little or no value, but, with improved equipment and experience, they may become valuable.