Accuracy of dwell position detection with a combined electromagnetic tracking brachytherapy system for treatment verification in pelvic brachytherapy

Background and purposeTo investigate the accuracy of dwell position detection with a combined electromagnetic tracking (EMT) brachytherapy (BT) system for treatment verification, by quantifying positional errors due to EM field interference in typical pelvic BT clinical settings.Materials methodsDedicated prostate cervix phantoms were imaged CT. For phantom, Utrecht applicator + interstitial catheters used. The implants reconstructed plans created 270/65 positions prostate/cervix phantom. Next, EMT experiments performed settings using prototype EMT/BT system. We quantified from surrounding equipment comparing planned EMT-measured positions. mean residual error between was calculated whole implant including applicator. analysis repeated only catheters.ResultsMean less than 0.5/0.4 mm found. applicator, large deviations up 2.4 Compared free set-up, CT patient bed environments showed larger catheters, but remained <1 all cases.ConclusionDwell is sufficiently accurate perform EMT-based verification. effect limited.