DVH Calculations

[priya...@gmail.com]

Hi

I want to do DVH calculations but the RTDose Header does not have DVH related Tags in them as present in your sample files.

Is there a way to still calculate the DVH ?

Regards

[Aditya Panchal]

Hi Priyanka,

The DVH related tags are only present if the original treatment planning system exported them. The DVH calculation actually won't use these tags even if they present.

The sample code shows how to calculate it independently of the tags.

Let me know if you need more detail or information.

Adit

--
-- You received this message because you are subscribed to the Google Groups dicompyler group. To post to this group, send email to dicom...@googlegroups.com. To unsubscribe from this group, send email to dicompyler+unsubscribe@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/dicompyler?hl=en
---
You received this message because you are subscribed to the Google Groups "dicompyler" group.
To unsubscribe from this group and stop receiving emails from it, send an email to dicompyler+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[priya...@gmail.com]

Thanks Aditya.

I am able to calculate the same now. I have some issues with DVH graph plotting.

Sample Code : 

print ('ROI -->')
print(structures[7]['name'])
calcdvh = dvhcalc.get_dvh(rtStructFile, rtDosefile, 7)

print( calcdvh.plot())

DVH(cumulative, 4844 bins: [0.0:48.439999999999998] Gy, volume: 179.84000000000489 cm3, name: 'RECTUM', rx_dose: 0 Gy)

print('HISTOGRAM')
BinsWidth =   calcdvh.bins[1] - calcdvh.bins[2]
plt.bar(calcdvh.bins[1:],calcdvh.counts,BinsWidth)
plt.axis([0.0, calcdvh.max+20, 0, np.amax(calcdvh.counts)])
plt.title('Histogram')
plt.show(block=True)

I want a cumulative histogram but seems , this is not so.

Regards
Priyanka

On Friday, September 22, 2017 at 6:04:51 AM UTC+2, Aditya Panchal wrote:

Hi Priyanka,

The DVH related tags are only present if the original treatment planning system exported them. The DVH calculation actually won't use these tags even if they present.

The sample code shows how to calculate it independently of the tags.

Let me know if you need more detail or information.

Adit

On Tue, Sep 19, 2017 at 4:18 PM, <priya...@gmail.com> wrote:

Hi

I want to do DVH calculations but the RTDose Header does not have DVH related Tags in them as present in your sample files.

Is there a way to still calculate the DVH ?

Regards

--
-- You received this message because you are subscribed to the Google Groups dicompyler group. To post to this group, send email to dicom...@googlegroups.com. To unsubscribe from this group, send email to dicompyler+...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/dicompyler?hl=en

---
You received this message because you are subscribed to the Google Groups "dicompyler" group.

To unsubscribe from this group and stop receiving emails from it, send an email to dicompyler+...@googlegroups.com.

[Aditya Panchal]

That looks correct to me. The DVH class instance states that it is a cumulative DVH.

If you are wondering why the volume in the plot is in cm3 instead of relative units, you can show relative units by accessing calcdvh.relative_volume instead of calcdvh.

That will only change the y axis, but the plot will be the same.

--
-- You received this message because you are subscribed to the Google Groups dicompyler group. To post to this group, send email to dicom...@googlegroups.com. To unsubscribe from this group, send email to dicompyler+unsubscribe@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/dicompyler?hl=en

---
You received this message because you are subscribed to the Google Groups "dicompyler" group.

To unsubscribe from this group and stop receiving emails from it, send an email to dicompyler+unsubscribe@googlegroups.com.

[priya...@gmail.com]

Thank. But that isn ot what i was looking for. I want a graph like this , attached.

Not sure if this is a standard term, but I am looking to Calculate DVH as Volume Percentage. Is that supported by default ?

[Aditya Panchal]

Ah, you are looking for a differential DVH. So you can write:

calcdvh.differential.relative_volume

or 

calcdvh.relative_volume.differential

The x axis will be dose bins and the y axis is a volume percentage.

The previous example you gave is called a cumulative DVH.

If you look at the module code, dvhcalc actually generates a differential DVH with absolute volume. It then uses the dvh module to transform it to a cumulative DVH. You can use the above properties/transforms to get it back to the original differential form but with relative volume in %.

I'm not sure if you're using spyder or another environment, but if you append .plot() to any dvh instance, it should plot via matplotlib.

--
-- You received this message because you are subscribed to the Google Groups dicompyler group. To post to this group, send email to dicom...@googlegroups.com. To unsubscribe from this group, send email to dicompyler+unsubscribe@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/dicompyler?hl=en

---
You received this message because you are subscribed to the Google Groups "dicompyler" group.

To unsubscribe from this group and stop receiving emails from it, send an email to dicompyler+unsubscribe@googlegroups.com.