Introduction: The fact that conventional intraoperative radiotherapy does not give the opportunity to exactly document the radiation volume applied and the dose distribution has been criticized in many ways. We would like to introduce a system for surgical navigation and documentation of flap positioning in intraoperative brachytherapy using the afterloading flap technique. Methods: Our system consists of an electromagnetic 3D-digitizer and a PC workstation. Spiral CT scans of the tumor region taken preoperatively are used for navigation and documentation of flap positioning, analogous to the procedure in neuronavigation. Registration is done via an external reference system which is attached to the iliac bone of the patient. Results: The mean accuracy of digitalization of the 100 spheres in a pelvis model is about 2.6 ± 0.5 to 3.7 ± 9.9 mm. The mean navigation accuracy is 2.4 ± 0.8 to 3.3 ± 0.8 mm. These figures correspond to the clinical experience of our surgeons. Discussion: The optimization of flab positioning by CT-guided navigation and the more accurate documentation of the dose volume and distribution in the patient is an important step on the way to improving the quality of individual radiation therapy. We are of the opinion that surgical navigation in the pelvic region should be subject to additional investigation in order to optimize the procedure.

1.
Flentje M, Frey M, Kuttig H, Kimmig B: Radiotherapy of locally recurring colorectal tumors. Prognostic factors, follow-up diagnosis and results (in German). Strahlenther Onkol 1988;164:402–407.
2.
Hansen RM, Ryan L, Anderson T, Krzywda B: Phase III study bolus versus infusion fluorouracil with or without cisplatin in advanced colorectal cancer. J Natl Cancer Inst 1996;88:668–674.
3.
Overgaard M, Bertelsen K, Dalmark M: A randomized feasibility study evaluating the effect of radiotherapy alone or combined with 5-fluorouracil in the treatment of locally recurrent or inoperable colorectal carcinoma. Acta Oncol 1993;32:547–553.
4.
Overgaard M, Overgaard J, Sell A: Dose-response relationship for radiation therapy of recurrent, residual, and primarily inoperable colorectal cancer. Radiother Oncol 1984;1:217–225.
5.
Tonus C, Kolotas CH, Appel P, Martin T, Zamboglou N, Nier H: Colorectales Carcinom – Behandlungsalternative durch intraoperative Radiotherapie mittels Afterloading-flab-Technik? Chirurg 1999;70:43–48.
6.
Sakas G, Schreyer LA, Grimm M: Visualization of 3D ultrasonic data; in Bergeron D (ed): IEEE Visualization. Washington, IEEE Computer Society Press, 1994, p 369.
7.
Sakas G, Walter S: Extracting surfaces from fuzzy 3D ultrasonic data: ACM computer graphics; in Cook R (ed): Computer Graphics Proceedings (SIGGRAPH). Los Angeles, ACM Press, 1995, p 465.
8.
Sakas G, Walter S, Hiltmann W, Wischnik A: Foetal visualization using 3D ultrasonic data; in Lemke HU (ed): Computer-Assisted Radiology. Berlin, Springer, 1995, p 241.
9.
Roessler K, Ungersboeck K, Dietrich W, et al: Frameless stereotactic guided neurosurgery: Clinical experience with an infrared based pointer device navigation system. Acta Neurochir (Wien) 1997;139:551–559.
10.
Eble M, Kallinowski F, Wannenmacher M, Herfarth Ch: Intraoperative Radiotherapie des lokal ausgedehnten und rezidivierten Rektumkarzinoms. Chirurg 1994;65:585–592.
11.
Kneschaurek P, Wehrmann R, Hugo C, Stepan R, et al: Die Flabmethode zur intraoperativen Bestrahlung. Strahlenther Onkol 1995;171:61–69.
12.
Lukas P, Stepan R, Ries G: Intraoperative Strahlentherapie mittels High-dose-rate Afterloading in Verbindung mit kombinierter Radio-/Chemotherapie beim fortgeschrittenen Rektumkarzinom. Chir Gastroenterol 1995;11:144.
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