This study reports the high value of VERT breast cancer-targeted education programs in improving RT knowledge and perhaps decreasing patient anxiety. Continued efforts are required to improve patients' accessibility to VERT in Australia, and to better understand the effect of VERT's unique educational features on patients' emotional and physical needs throughout their RT.

This topical review provides an up-to-date overview of the theoretical and practical aspects of therapeutic kilovoltage x-ray beam dosimetry. Kilovoltage x-ray beams have the property that the maximum dose occurs very close to the surface and thus, they are predominantly used in the treatment of skin cancers but also have applications for the treatment of other cancers. In addition, kilovoltage x-ray beams are used in intra operative units, within animal irradiators and in on-board imagers on linear accelerators and kilovoltage dosimetry is important in these applications as well. This review covers both reference and relative dosimetry of kilovoltage x-ray beams and provides recommendations for clinical measurements based on the literature to date. In particular, practical aspects for the selection of dosimeter and phantom material are reviewed to provide suitable advice for medical physicists. An overview is also presented of dosimeters other than ionization chambers which can be used for both relative and in vivo dosimetry. Finally, issues related to the treatment planning and the use of Monte Carlo codes for solving radiation transport problems in kilovoltage x-ray beams are presented.

Two new detectors (0.015 cm3 ion chamber from PTW, 0.6 mm diameter diode from Scanditronix AB) designed specifically for use in small stereotactic fields were compared against similar, more routine, detectors (0.125 cm3 ion chamber, parallel plate chamber, shielded and unshielded diodes and film). Percentage depth doses, tissue maximum ratios, off-axis ratios and relative output factors were compared for circular fields in the 40-12.5 mm diameter range, with a view to identifying the optimum detector for stereotactic beam data acquisition. Practical suggestions for beam data collection and analysis are made, with an emphasis on what is achievable practically in radiotherapy departments where the primary demand is to provide a routine service. No single detector was found to be ideal, and neither of the two new measurement devices had any significant advantages over more routine devices, in the situations measured. Although the new 0.015 cm3 ion chamber was an improvement on a 0.125 cm3 ion chamber in the measurement of profiles, it was still too large when compared with a diode. The new small diode had a low signal to noise ratio which made reliable data difficult to extract and its only advantage is possibly improved resolution in fields smaller than the range tested. The use of a larger unshielded diode is recommended for all measurements, with the additional cross-checking of data against at least one small ion chamber and film. A simple method of obtaining reliable output data from the detectors used is explained.

A number of general conclusions are evident: (1) small field OR(det) are very sensitive to the simulated source parameters, and therefore, rigorous Monte Carlo linac model commissioning, with respect to measurement, must be pursued prior to use, (2) backscattered dose to the monitor chamber should be included in simulated OR(det) calculations, (3) the corrections required for diode detectors are design dependent and therefore detailed detector modeling is required, and (4) the reported detector specific correction factors may be applied to experimental small field OR(det) consistent with those presented here.

In general, the proposed methodology removes much of the ambiguity in reporting and interpreting small field dosimetric quantities and facilitates a clear dosimetric comparison across a population of linacs.

Extremely careful experimental methodology including the measurement of dosimetric field size at the same time as output factor measurement for each field size setting and also very precise detector alignment is required at field sizes at least ≤ 12 mm and more conservatively ≤ 15 mm for 6 MV beams. These recommendations should be applied in addition to all the usual considerations for small field dosimetry, including careful detector selection.

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The Agility collimator is a low leakage, high definition collimator where both the MLC and the sculpted diaphragm have been optimized for dynamic treatments.