This neuroanatomical illustration explains the complex venous pathways that travel through the quadrigeminal cistern, a dilation of subarachnoid space between the midbrain, cerebral hemispheres, and cerebellum.
To accurately depict the intricate neuroanatomy in this region, I reconstructed anonymized patient CT and MRI scans to create 3D models that I referenced for accurate size and structure relationships.
Continue reading below to learn more about how I created these reference models from DICOM data, and how I translated these models to a rendered illustration.
Segmenting DICOM data in OsiriX and importing to Zbrush
Using the DICOM segmentation features of OsiriX software, I isolated the soft tissue structures of the brain from an anonymized MRI scan and the skull from a CT scan of another patient. I generated these data sets as 3D models using the 16-bit threshold editor and explored the anatomy with various slices through the models (below).
Approximate slice locations in an anonymized patient model created in OsiriX.
After exporting the whole models and importing them to Zbrush, I aligned them as if they had existed in the same patient. I then used a live Boolean subtraction to create a clean window in the models and visualize the internal structures of the quadrigeminal cistern.
Combined 3D model of DICOM data-derived brain and skull to be used as a reference for my illustration (left), and close up of quadrigeminal cistern (below).
Beginning the Illustration
Referencing my combined model in an oblique view as well as the original 3D reconstructed patient models and neuroanatomy reference books, I created a clean outline to preserve anatomical relationships and detail in my final illustration. This was achieved by creating separate traditional pencil outlines for each structure (skull, cerebrum & cerebellum, cut edge of the dura, venous structures, and the cut edge of the cranium) and aligning them in Adobe Photoshop.
Animated GIF of my pencil outlines, scanned in and aligned in Photoshop (left).
The final color landmark illustration, which was enlarged for the close-up inset of the quadrigeminal cistern (below).
