[Computer-assisted control of CT-guided caudo-cranial puncture access route using the triangulation method].

PURPOSE: To control the position of a puncture needle on an access route, which is not parallel to the CT-scan, using control scans not showing start and target points.

METHODS

A software tool has been developed. After CT for biopsy planning x/y coordinates and table position of start and target points have to be determined on CT-scans. The software calculates x/y coordinates of the access route for every table position, which must be marked interactively on control scans. The accuracy of the programme was proven experimentally and the method was used in five patients.

RESULTS

There was no difference between the calculated and measured access route in the experiment. Four of five patients were punctured successfully using our method.

CONCLUSION

Our method is a promising procedure to control a CT-guided caudo-cranial biopsy access route.