Occult dorsal carpal ganglion: comparison of US and MR imaging.

PURPOSE

To evaluate the usefulness of ultrasound (US) and magnetic resonance (MR) imaging in patients suspected of having an occult dorsal carpal ganglion.

MATERIALS AND METHODS

The authors prospectively studied US and MR images of 14 wrists in 13 consecutive patients suspected of having an occult dorsal carpal ganglion.

RESULTS

Eleven dorsal carpal ganglia were identified with US and nine with MR imaging. One patient refused the MR imaging study. Of two equivocal cases at MR imaging, one was a ganglion and another was a compressible capsular recess, as determined at US. One ganglion was missed with both techniques. The average diameter of the ganglion cysts was 4.9 mm.

CONCLUSION

MR imaging and US are equally effective in the detection of occult dorsal carpal ganglia. Because of its dynamic capabilities and lower cost, US should be the initial imaging procedure for suspected occult dorsal carpal ganglia.