Determination of the accuracy of implant reconstruction and dose delivery in brachytherapy in The Netherlands and Belgium.
OBJECTIVE
To gain insight into the accuracy of brachytherapy treatments, the accuracy of implant reconstruction and dose delivery was investigated in 33 radiotherapy institutions in The Netherlands and Belgium.


METHODS
The accuracy of the implant reconstruction method was determined using a cubic phantom containing 25 spheres at well-known positions. Reconstruction measurements were obtained on 41 brachytherapy localizers, 33 of which were simulators. The reconstructed distances between the spheres were compared with the true distances. The accuracy of the dose delivery was determined for high dose rate (HDR), pulsed dose rate (PDR) and low dose rate (LDR) afterloading systems using a polymethyl methacrylate cylindrical phantom containing a NE 2571 ionization chamber in its centre. The institutions were asked to deliver a prescribed dose at the centre of the phantom. The measured dose was compared with the prescribed dose.


RESULTS
The average reconstruction accuracy was -0.07 mm (+/-0.4 mm, 1 SD) for 41 localizers. The average deviation of the measured dose from the prescribed dose was +0.9% (+/-1.3%, 1 SD) for 21 HDR afterloading systems, +1.0% (+/-2.3%, 1 SD) for 12 PDR afterloaders, and +1.8% (+/-2.5%, 1 SD) for 15 LDR afterloaders.


CONCLUSIONS
This comparison showed a good accuracy of brachytherapy implant reconstruction and dose delivery in The Netherlands and Belgium.
Elfrink
R J
RJ
Department of Medical Physics, Elkerliek Hospital, P.O. Box 98, 5700 AB, Helmond, The Netherlands.
Kolkman-Deurloo
I K
IK
van Kleffens
H J
HJ
Rijnders
A
A
Schaeken
B
B
Aalbers
T H
TH
Dries
W J
WJ
Venselaar
J L
JL
D001530:Belgium; D001918:Brachytherapy / Q000379:methods*; D001940:Breast / Q000528:radiation effects* / Q000601:surgery*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D016462:Mammaplasty; D009426:Netherlands