Role of High-Variable Frequency Ultrasound in Preoperative Diagnosis of Glomus Tumors

Background: Accurate preoperative imaging of glomus tumors improves the outcome of surgery. Currently, MRI is frequently recommended for preoperative assessment although this requires the use of intravenous contrast media and may be less efficient at detecting tumors <3 mm in diameter. Recent developments in highvariable frequency ultrasound (HVFUS) mean re-evaluation of the possible role of ultrasound in the preoperative detection of glomus tumors appears appropriate. Objective: To assess the capabilities of contemporary HVFUS in relation to preoperative detection and characterization of glomus tumors. Methods: Seven patients (all women, aged 38–66 years, mean age 51.3 years) suspected on clinical grounds of having a glomus tumor were evaluated with high-resolution color Doppler ultrasound using a compact linear probe that varies from 7 to 15 MHz in frequency. The results were compared with histology. Results: The tumors and their exact location were identified in all cases. The tumors appeared as hypoechoic nodules with high vascularity in the nail bed, together with remodeling of the underlying bone. Small tumors (0.9 mm depth) were also identified. Arterial flow was identified inside all tumors. Peak systolic velocity varied greatly, but the mean was 11.3 ± 9.1 cm/sec (range: 3.7–26.1 cm/sec). Conclusion: Recent developments in HVFUS have made it possible to identify small glomus tumors in real time and with high resolution. The procedure does not require administration of intravenous contrast media and provides good information about lesional blood flow and the surrounding structures. These results suggest that HVFUS may play a larger role in the preoperative assessment of glomus tumors in the future.