# Is there an easy method to calculate the Cobb Angle using a 3D Slicer module?

**URL:** <https://discourse.slicer.org/t/is-there-an-easy-method-to-calculate-the-cobb-angle-using-a-3d-slicer-module/10189>\
**Category:** Support\
**Tags:** dicom, quantitative\
**Created:** [February 10, 2020, 5:08pm UTC](https://discourse.slicer.org/t/is-there-an-easy-method-to-calculate-the-cobb-angle-using-a-3d-slicer-module/10189 "2020-02-10T17:08:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![stevenagl12](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/stevenagl12/32/3391_2.png) [@stevenagl12](https://discourse.slicer.org/u/stevenagl12)\
**Post date:** [February 10, 2020, 5:08pm UTC](https://discourse.slicer.org/t/is-there-an-easy-method-to-calculate-the-cobb-angle-using-a-3d-slicer-module/10189/1 "2020-02-10T17:08:49Z")

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I have CT scans that contain the spine and am trying for an easy way to get the Cobb Angle using them.

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [February 10, 2020, 6:18pm UTC](https://discourse.slicer.org/t/is-there-an-easy-method-to-calculate-the-cobb-angle-using-a-3d-slicer-module/10189/2 "2020-02-10T18:18:18Z")

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Cobb angle is measured on 2D x-rays, which is essentially AP projection of CT image. You can create the projection image using [this script](https://www.slicer.org/wiki/Documentation/Nightly/ScriptRepository#Thick_slab_reconstruction_and_maximum.2Fminimum_intensity_volume_projections) and then use angle markups angle widget (in recent Slicer Preview Release). We don’t have 4-point angle measurement yet (we’ll probably add it at some point, it would be very easy), so if angle widget is too inconvenient then you can draw 2 lines and compute the angle using a short Python script.

You might also find Scoliosis extension useful, which measures vertebral angles from 3D points defined directly on a volume-rendered CT.