 My name is Caleb Sample and I'm happy to present this video summary of our article incorporating PradaGlan in homogeneity into head and neck treatment optimization through the use of artificial base plans. Picture a desolate desert with a tumbleweed drifting across a hard, cracked floor. Well that floor is probably close to what your tongue would look like if you stopped producing saliva. The condition of having a dry melt due to low saliva production is called xerostomia. It's known to drastically diminish the quality of life of whoever has it and unfortunately it is quite often a severe side effect for head and neck radiotherapy patients. This is a result of radiation damage to the saliva glands and in particular the biggest saliva glands which run either side of the mouth just in front of the ears and are called the PradaGlands. It seems to me that the old saying you don't know a good thing till it's gone applies perfectly to saliva. In recent years, the onset of volume-modulated arc therapy or V-Met has allowed for radiation to be swept in 360 degrees around the patient, all being reshaped by a high-density collimator so that tumor tissue can be targeted while a healthy organ such as the PradaGland can be spared as much as possible. The reshaping of the radiation is optimized automatically by the planning system based on certain constraints set by a treatment planner. The current standard of care for minimizing dose to PradaGlands is to constrain the mean dose to the glands. A constraint on the whole mean dose suits a gland that has a homogenous dose response, but for inhomogeneous organs it fails to account for any variance of function aloe view within different subregions. The relative importance of different subregions within the PradaGlands for predicting post-treatment serostomia was recently quantified, revealing that radiation to certain chunks within the PradaGland appeared to be much more detrimental than radiation to other chunks. I will work aims to incorporate this new data into the treatment planning process. Treatment planning systems allow patient dose histories to be included in optimization by loading previously received base plans. This allows for dose already received in previous plans to be included in the dose calculation for the new plan. What we've done is retroactively create artificial base plans for patients which assign dose only within PradaGlands, with different amounts in different regions, such that regional dose is proportional to importance. These plans can be used to trick the optimizer into thinking that more important PradaGland regions have already received more dose than less important regions, and if a planner sets an upper bound dose constraint for the PradaGland, important areas will be preferentially spared over unimportant areas. Treatment plans for 15 patients were then optimized with five different types of base plans, as well as without base plans. The resultant sub-regional PradaGland mean doses were calculated and then run through a predictive model for saliva output loss at one-year post-radio therapy. Significant reductions in dose to important sub-regions of the PradaGland were found, as well as significant improvements in saliva output predictions for patients planned with artificial base plans. In summary, a universal method for incorporating sub-organ dose constraints into V-match treatment planning has been featured as an effective means of steering dose away from important regions of the PradaGland. This method may also be applied to other organs at risk for which spatial important stat exists.