Forums › Deep Inspiration Breath Hold › VisionRT DIBH Supraclav/Chest Wall with BOLUS + IM Field(s) › Reply To: VisionRT DIBH Supraclav/Chest Wall with BOLUS + IM Field(s)
Michael Tallhamer, MSC, DABR
We used to do these types of treatments with matching electron IMN fields but they have fallen out of favor with our docs as they now would rather use “deep tangents” to treat these IMNs. The BH treatments with matching e- IMN fields were always challenging but we don’t find much issue with standard bolus CW and matched SC fields.
As far as the BH with IMN e- fields go the easiest thing we found that worked well (again while we were still doing these) was to set your patient up to the FB surface then have them breath to the BH DICOM surface. If everything looks good we would switch to our monitoring field (or bolus field if you have had the VRT training) where we would have them breath into the BH DICOM and when it matches place the bolus and snap a reference. Under this field you have 2 ROIs one standard ROI for monitoring the tangents with bolus and one over the contralateral aspect of the chest to use for monitoring during the IMN e- field so we had something to look at outside of the e- cone. Before we would start treatment all we would do is again have them breath into the reference BH with the bolus and then check both the ROI for the tangents and the ROI on the contralateral side for use during the IMN field to make sure they correlated well (they should). They both had to be within tolerance before treatment could continue. If your docs like to check the match line (as ours did) we would draw the Med boarder prior to placing the bolus under BH and then when we switched to the IMN e- field we would have them BH to the contralateral ROI position and check the e- light field against the previously drawn Med boarder.
Hope that helps. Deep tangents are the way to go IMO!