Purpose: In afterloading therapy, the exact placement of the applicator is crucial for the result of radiotherapy. A deviation of few millimeters from the target leads to a significant reduction of radiation energy to the tumor.
Methods and materials: We present a new method using a computer-assisted device for three-dimensional placing of afterloading probes based on CT scans that allows for the exact placement.
Results: Target points have been reached with an accuracy of 0.6 mm. Since 1991 we have used this technique for 24 clinical applications in 11 patients with recurrent neoplasms in the region of the paranasal sinuses and nasopharynx for palliative treatment.
Conclusions: The presented method is a reliable and precise procedure for the positioning of afterloading probes, avoiding the inaccuracy of the traditional methods.