Dr. S’ new favorite neuroanatomical term is “parieto-occipital sulcus”. It just rolls off the tongue and leaves a smile behind, doesn’t it. The parieto-occipital sulcus is a groove that separates the parietal cortex – underneath the upper wall (Latin paries) – from the occipital cortex – (Latin, behind the caput or head). It is depicted as a red line in the accompanying graphic. You can’t see much of it on the outside of the brain, it is more pronounced on the inside of each hemisphere.
While Dr. S reluctantly came to see the logic behind removing Kristine’s lesion, the question was always how to get at it. Visions of Indiana Jones slashing through the jungle with a machete to find the cosmic -jewel came to mind. The recently available option of using a thin laser-tipped probe to drill down and zap the tissue seemed attractive, but not without risk.
But no, based on the MRI imaging, the surgeon devised a plan to run along this sulcus, minimizing the going through brain tissue that was so anxiety provoking. Dr S refers to this as minimally invasive brain surgery, when it’s being done to someone else. Internalize this graphic & you will understand that super cool stripe under Kristine’s hat.
Let’s reflect on that. Fifty years ago, one could have an X-ray film. Thirty years ago, a series of X-ray based CT slices. I suppose the surgeon would just open you up, takes a look around, and decide what if anything could be done. The mathematics of 3D image reconstruction and computational power to execute it all came along in our lifetimes, as well as understanding and harnessing the physics of spinning protons. Now the well-studied and well-equipped surgeon pulls this stuff up on the screen and says “Ah, follow the sulcus and we’ll be in the right neighborhood”. I don’t at all take it for granted that our collective brain should be potent enough — especially considering its extensive library of failings — to assemble all these components and in so doing be able to look in on itself.
Dr S notes that “sulcus” can translate to “furrow”. That could be like the furrowed brows in evidence around town over the past few years, or the furrowed fields of this place we call home. I suppose a deep enough furrow qualifies as a “rut”. In this case, the rut could be “Ah, temporal lobe epilepsy, best practice is to chop the temporal lobe, hippocampus &c” — which replaced an older rut of “medicate to the point of disability”. Granted, these are science-based, but that also means it takes more and better science to find better ruts.
Anyway, it occurs to me that by following the anatomical rut, the surgeon was freed from the conventional-wisdom rut, and given the outcome so far, one can only be Thankful for every person and institution that made that a possibility.