Author: Thomas Furno, Arjen Winkel, Ramtin Zakikhani 👨🔬
Affiliation: Genesis Care USA, QLRAD, SMH 🌍
Purpose: To quantify the dosimetric impact of the newly introduced “Inframammary Fold (IMF) Breast WedgeTM ” device by QLRAD inc. in the region of the inframammary fold during breast radiotherapy.
Methods: The IMF Breast WedgeTM is an air equivalent (–900 HU) foam and is intended to be placed between the breast and chest wall to create a separation. A breast phantom was created by using sheets of folded bolus. The sheets of folded bolus were then placed on top of flat plates of Solid Water totaling 11 cm in thickness. The sheets of folded bolus created a phantom that was approximately 14 cm wide, 14 cm long and 6 cm high. The Solid Water immediately under the folded bolus simulated the chest wall. A clinical two field tangential step and shoot radiation treatment plan was created with Varian’s EclipseTM software and delivered with a Varian TruebeamTM linac. Thermoluminescent (TLD) dosimeters were placed at various locations on the breast phantom to measure the dose delivered by the radiation treatment plan and then compared to the calculated dose in the treatment planning system.
Results: A reduction of dose was found at the chest wall by almost 85% when the IMF Breast WedgeTM device was present in the treatment plan compared to the plan without the device. The TLD measurements showed a similar effect when the IMF Breast WedgeTM was placed to create a separation between the breast and chest wall with a dose reduction of about 83%.
Conclusion: Use of this novel device reduced the dose to the chest wall significantly and could extend to other skin folds throughout the body treated with a similar technique. The benefits of reduced dose to skin folds should lead to improved patient treatment outcomes through lower skin toxicity and reduced treatment breaks.