Magnetic resonance imaging in the diagnosis of glomus tumours of the hand.

This paper studies the sensitivity, specificity and predictive values of MRI in the diagnosis of glomus tumours of the hand and investigates the final diagnosis and outcome in cases with false positive or negative imaging tests. A total of 42 cases with the clinical diagnosis of a glomus tumour were included in the study. All patients underwent MRI and the results of MRI were correlated with the final histological diagnosis of the excised lesion. MRI had a sensitivity of 90%, a specificity of 50%, a positive predictive value of 97% and a negative predictive value of 20%. The four cases in which the MRI was negative all proved histologically to be glomus tumours. All four tumours were small (2-3mm in diameter) and the lack of delineation of the lesions by MRI was attributed to their small size. Despite negative MRIs, surgical exploration identified the glomus tumours. Based on the results of the current study and the cost of MRI, the senior author has stopped ordering pre-operative MRIs in patients clinically diagnosed with a glomus tumour.