Reflect on the DVH topic in week four. Summarize your interpretation and understanding of the readings. Provide Website URLs that support your summary and provide more insight to the rest of the class. Also, make sure you include when you would use each type of DVH.
DVHs are a great way to evaluate a plan or compare two plans against each other, as they show regions of high dose, low dose, and uniform dose for each anatomic structure.1 For instance if you are comparing an arc plan to a step and shoot IMRT plan the DVH is a quick tool to see if you are covering your PTV the way you should, and which plan is better at sparing the organs at risk. However, the DHV is only accurate if you have drawn your organs at risk properly during your contouring.
There are two forms of DVH, a cumulative and a differential. The cumulative, the most common, is represented by showing the volume of a certain structure receiving a certain dose or higher.1 This DVH is able to form lines in the form off waves or more hopefully a line that comes straight down and trails off to the right. While also creating a line that hopefully stays even across the top of the plot and runs straight down once it reaches its total dose for PTVs. The differential DHV is shown as a volume receiving dose within a specified interval of dose.1 With the differential DHV it is not able to show mean doses and maximum does of structures. Thus, making it less clinically useful.
https://www.researchgate.net/figure/245537017_fig2_Example-of-a-comparative-DVH-for-a-breast-plan-The-curves-calculated-by-the-PBC This website shows a DVH with some of the lines as I talked about them.
DVHs are a great way to evaluate a plan or compare two plans against each other, as they show regions of high dose, low dose, and uniform dose for each anatomic structure.1 For instance if you are comparing an arc plan to a step and shoot IMRT plan the DVH is a quick tool to see if you are covering your PTV the way you should, and which plan is better at sparing the organs at risk. However, the DHV is only accurate if you have drawn your organs at risk properly during your contouring.
There are two forms of DVH, a cumulative and a differential. The cumulative, the most common, is represented by showing the volume of a certain structure receiving a certain dose or higher.1 This DVH is able to form lines in the form off waves or more hopefully a line that comes straight down and trails off to the right. While also creating a line that hopefully stays even across the top of the plot and runs straight down once it reaches its total dose for PTVs. The differential DHV is shown as a volume receiving dose within a specified interval of dose.1 With the differential DHV it is not able to show mean doses and maximum does of structures. Thus, making it less clinically useful.
https://www.researchgate.net/figure/245537017_fig2_Example-of-a-comparative-DVH-for-a-breast-plan-The-curves-calculated-by-the-PBC This website shows a DVH with some of the lines as I talked about them.
- Khan FM. Electron Beam Therapy: The Physics of Radiation Therapy.5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2014: 423-424.
- ResearchGate. Website. https://www.researchgate.net/figure/245537017_fig2_Example-of-a-comparative-DVH-for-a-breast-plan-The-curves-calculated-by-the-PBC. Accessed April 19, 2017.