Left Chestwall

Summary 

This dataset is from the Varian Medical Affairs collection (found in the “Thorax” library). The dataset is labeled as Lt Chestwall+LN 50Gy (NSABP51/RTOG1304/AllianceA221505). In this reference plan, a 5 mm conventional uniform thickness bolus was used, one that was quite large in terms of area covered.

For comparison, in our media gallery we show an automated, variable-thickness bolus that provides enhanced buildup for the chest wall target. We also show an alternative that would provide additional buildup for the lymph nodes in case the planner finds it necessary to improve coverage of the shallow portion of LN target voxels.

Gallery 

1. Manufactured OptiBol bolus with 10 mm buildup to the underlying target to achieve coverage better than the conventional 5 mm. The bolus is shown here on a 3D-printed holder.
2. Depth-volume histograms showing histograms of the minimum depth of target voxels for (a) no bolus, (b) conventional 5 mm bolus, and (c) variable-thickness OptiBol with goal buildup of 10 mm.
3. Manufactured OptiBol with linear laser registered to the sagittal alignment guide on the anterior of the bolus at the user-defined reference plane.
4. Comparison of the size of the conventional uniform-thickness 5 mm bolus vs. different options for automated, variable-thickness OptiBols. The OptiBols are smaller in terms of region covered because they’re target-based rather than a guesstimate based on conventional methods. It’s important to note that target-based design may lead to smaller, and therefore less-expensive, boluses.
5. An alternative OptiBol that adds buildup to the superior lymph node target.