- Fast & Simple.
- Easy to Use.
- Low Cost.
- Provides Confidence.
- Detects Gross Defects.
- Demonstrates Accuracy.
All the Stages of the Treatment process; CT imaging, Target and Critical Organ delineation, Dose
prediction, Treatment parameter transfer and Machine performance contribute to the Treatment Dose. Audit
is recognised as an exemplary method to evaluate treatment delivery systems and methods and provide
confidence 1-3. Audit can be performed with a simple phantom to verify and provide assurance that the dose
delivered is within acceptable limits from that prescribed. Audit is of great value for clinical trials although it
can require considerable manpower and equipment costs to implement. Nevertheless the routine use of
audit, often on an individual patient basis to verify the accurate delivery of complex treatments is actively
undertaken in well resourced facilities. For rapid Audit a low cost audit method is possible with a MicroPhantom which enables the process from CT imaging through to dose delivery to be audited very quickly,
with a minimum of time and equipment to provide confidence in the Treatment process.
The Micro-Phantom consists of three features.
- A compact cylindrical drum which can be water filled to provide a body of uniform material density within which heterogeneous inserts can be inserted and a cavity located on the axis of rotation of the phantom at which dose measurements are made. A scribed line around the phantom identifies the Central Slice upon which the treatment should be planned.
- Two cylindrical cavities into which calibrated heterogeneous drums can be inserted. The location of these cavities are positioned to ensure separation between applied fields which intersect on the location of the dose measurement cavity located on the axis of rotation of the phantom.
- A cavity on the axis of rotation of the phantom with the cavity profiled to receive a Farmer 2571 typ chamber and enable absolute dose measurements to be made directly. The scribed line around the phantom is coincident with the measurement point of the ionisation chamber.