Week 2 - Joseph

Though last week my forays into the hospital immersion experience were primarily dominated by surgery, this week I broadened my approach to neurosurgery to include experiences with the diagnostic and research aspects of the field. On Monday and again on Thursday I went to clinical visits with my mentor, which was a very interesting, and very different, perspective on patient care. Whereas I had seen patients unconscious on the operating table for surgery and in the ICU when I attended rounds with neurology, in-office appointments were quite different.

These patients came in two varieties: the person who was wondering what was wrong, and the person who had been fixed. For the former, it was a mixed bag. Some cases were genuinely interesting, such as a man who was told that they had coincidentally found a hemangioblastoma that was occupying 80% of his spinal column. It was a miracle that he was not already quadriplegic, that his spinal cord was somehow still functional. I watched as Dr. Stieg explained that the man had a choice: wait a period of time (on the order of years) and become quadriplegic for certain, or get surgery now and hope that the decompression of the spinal cord from tumor removal did not cause just that anyway. As I would have expected, my mentor advised surgery, but honestly admitted it was a tough call. The difficulty was evident not only on the man’s face, but also on his daughter’s. She was just entering high school. And he was not the only one who faced a hard choice. A far younger man who had already undergone neurosurgery once before was shown a CT scan of a cavernous malformation sitting on the top of his brain stem. His choice was also interesting: he could have surgery, which carried a 5-10% risk of damaging the motor cortex slightly, or elect to leave it alone, which carried an 8% chance of bleed per year that would cause similar damage. My mentor noted that the defect was an absolutely perfect candidate for surgery, and that any possible (though statistically unlikely) damage as a result would only affect fine motor control. The twist? The man was just finishing graduate school as an artist. Again, Dr. Stieg suggested surgery, but again admitted it was not an easy choice. The man left undecided. I must admit I was moved by the difficulty of these choices. Previous encounters with neurosurgery were after the decision had been made; seeing the decision process added a new level of understanding for the complicated relationship between a patient and a surgeon.

But for every patient that had to face such a decision, there were three that were told there was nothing wrong with them. This might actually have been sadder to watch, actually. I watched young and old people alike, complaining of head pain that seemed to legitimately be causing them severe pain and stress (sometimes pre-op, sometimes post-), be told that there was simply nothing wrong from a surgical perspective, and they would have to search elsewhere for answers and treatment. The trouble was no one comes to neurosurgery first, it’s always down the line as you get increasingly desperate and worried. Being told that there was nothing a neurosurgeon could do to help seemed particularly depressing to many, despite the fact that it often contained assurance that they were not going to drop dead in the street tomorrow (because that would definitely show up on the MRI!).

All that being said, I mostly enjoyed the latter flavor of cases, the regular check-ups with patients who had had surgery done by Dr. Stieg at some point in the past. They were almost exclusively older, nice people who had developed a relationship with my mentor over years of post-op visits, and they were all happy to see him and happy to hear all was still well with their brains. Some even brought home-cooked food as a continuing sign of thanks for all he had done for them. My wife (a student in veterinary school also at Cornell) always tells me that they constantly drill into young medical students that the ability to develop a rapport with your patients is as important as being able to treat them. It was clear that Dr. Stieg was a master at doing just that, and as a credit to him, it clearly made him a better doctor.

I also attended my first weekly neurosurgery conference on Monday, which I am happy to report demonstrated that at least one stereotype about surgeons is not true: surgeons CAN be talked out of surgery! To back up a bit, a conference is where doctors meet to discuss their patients’ cases and ask for input and consensus concerning treatment. This particular conference was of course primarily neurosurgeons, but also included radiologists and neurologists who lent their own less surgically focused opinions to discussions of difficult cases. I was surprised at how often everyone agreed on when an aneurysm was too difficult to treat, as was the case with one woman who had a basilar fusiform aneurysm which everyone agreed quite readily as being simply too risky to clip or coil. Tumors and cysts of various sizes and positions were also discussed, each time lead by a re-diagnosis by the radiologist, a suggestion by the neurologist, and a discussion by all present. It was... well, let’s say reassuring to see that doctors are willing to seek input from their peers before assuming they simply by default know best and take a drill to your skull.

As Dr. Frayer would say, I also continued to “collect surgeries” – another meningioma removal (this one fully intact, actually; it resembled a walnut), a couple ventriculoperitoneal shunt placements for treatment of hydrocephalus. I made an effort to seek out surgeries that were different from what I had seen last week. The most interesting surgery I saw was bilateral deep brain stimulation done on an awake patient for insertion of electrodes as a treatment for his Parkinson’s disease. It was easily the most delicate and technically complex surgery I have witnessed to date. To summarize the spectacle, the goal was to place electrodes in the subthalamic nuclei (SNT), a motor region underneath the hypothalamus relatively deep within the brain, for constant delivery of electrical current that would suppress the man’s constant tremors, which were easily visible underneath the blanket covering him for surgery. A trajectory was determined by aligning a brain CT taken right before the surgery with real-time X-rays done on the table, following which holes were carefully drilled in the skull. It was honestly a completely different surgical procedure compared to the rapidity I’d seen in the past for cranial entry… probably had something to do with, you know, the actually awake status of the patient. A rather bulky apparatus that resembled a giant protractor allowed precise adjustment and calibration of the insertion trajectory, the completion of which was followed by careful insertion of the electrodes themselves. Now this was legitimately a feat of biomedical engineering to behold, as the electrode insertion device could pick up the electrochemical activity of the cells it passed through, which, with a combination of signal processing and a good ear, allowed the surgeon (Dr. Kaplitt) to determine when he had reached not just the SNT, but the exact position in the three-dimensional space that was most ideal for stimulation. And he hit it perfectly on both approaches, which the on-site vendor for the device confessed to me hardly ever happens, indicating Dr. Kaplitt was very, very good at what he does. This is where the patient played a role, too, as the specific sounds they were searching for were generated by him flexing and relaxing various appendages in rapid succession. But the truly magical part of the surgery was watching them connect the electrodes to a voltage source, turn it on, and then watching the tremors gradually and completely stop as the voltage was increased and optimized. As if having your brain open while conscious wasn’t shocking enough in general, you honestly should have seen the look on the man’s face when he lifted his hand in front of his face and noted with amazement that it was not shaking. Upon further conversation with the vendor I learned that at an appropriate time after the surgery, the exact electrical stimulation would be calibrated using variable voltage, pulsewidth, and frequency optimization to maximize tremor reduction while minimizing any neurological defect. The mechanical programming of a global neuron response of such magnitude, to this humble biomedical engineer at least, was truly a feat to behold indeed.

Friday proved to be what I am going to begin referring to as my “graduate student day”. With my mentor out of town, I worked both on my medical research project (which currently is vacillating between a project focusing on ultrasound disruption of the blood brain barrier for drug delivery applications and a completely unrelated viral vector gene delivery project) as well as on my thesis project back home (which, as my thesis advisor is keen to remind me from time to time, I should be writing a paper on). It was actually a fun reminder of why I enjoy being a PhD student – reading papers, brainstorming ideas, familiarizing myself with protocols, and regularly transitioning between very diverse topics to keep my focus sharp (for the record, the paper I’m writing for journal submission is on nanobiotechnology applications for vaccine delivery, so… again, completely unrelated). I have a meeting with Dr. Stieg’s collaborator on Monday (the Dr. Kaplitt mentioned above, incidentally) to finalize project ideas, at which point it seems likely I’ll be heading for some lab work on top of clinical and OR immersion. And here I thought I opted out of the MD-PhD path!

As a concluding note, the patient I mentioned in my last post who had not yet woken up following her traumatic incident on the operating table gained full consciousness on Monday (five days after the surgery). When last I checked in, they were still gradually assessing her cognitive function. Dr. Frayer suggested that it was a good thing to follow patient cases like this, so here’s hoping for a full recovery by next week.