"Sukeroku sign" and "dent internal-capsule sign"--identification guide for targeting the subthalamic nucleus for placement of deep brain stimulation electrodes.

INTRODUCTION

The purpose of this study was to assess the usefulness of signs ("Sukeroku sign" and "dent internal-capsule sign") for the recognition of subthalamic nucleus (STN).

MATERIALS AND METHODS

Five Parkinson's disease cases in which there was a successful placement of deep brain stimulation (DBS) electrodes at the STN were retrospectively reviewed. Five radiologists who were not engaged in localization of STNs in clinical practice were asked to locate the STNs before and after instructions on the signs. We evaluated the deviation between the reader-located points and the location of the DBS electrode for which there had been a successful installation.

RESULTS

After instruction, there was a significant reduction in the deviation between the reader-located points and the DBS electrode. The time required for localization was also reduced after the instructions.

CONCLUSION

Sukeroku sign and dent internal-capsule sign are feasible indicators of STN and seem to be useful in helping to identify the STN.