Nasal Cavity Segmentation

Hello
I wanted to ask for advice on nasal cavity segmentation. (turbinates and sinuses).
I have my CT Scan dataset and have resampled it, which has helped a lot.
Using the threshold, level tracing, paint, erase, and logical operators, I can create a model of the nasal cavity, but the problem is the time required to go through all the slides.
I have used ITK image filters, denoising, and centerline. They help to a degree, but the problem is that the threshold doesn’t create a full segment.
I was wondering if anyone has suggestions.
Best regards,
Arash