How can I segment cartilage from paranasal sinus tac

I am trying to segment nasal cartilage from a CT scan of the paranasal sinuses, but I have not been able to accurately locate the threshold so that this area to be segmented can be marked.
Could you please help me ??

thank you !

There is not enough contrast to easily segment the nasal cartilage, you will have to do that manually and can do that only if the CT is of high quality… I have tried the same for many years…

Playing with contrast helps a lot when you need to segment a structure like that .
You can use an option in contrast tool to enhance the area you work in . It helped me many time .
you will most likely end up manually painting it .
but remember there are a lot of tool to make it easier like smudge paint and fill holes

Note that once you segmented a few dozens cases, you can start to train an AI segmentation model using MONAILabel extension. Since this is a difficult segmentation task (thin structures and low contrast), so you might need a few hundred images for robust and accurate segmentation.