
Private Practice Issue 36:
FAKE PLASTIC TREES: Creating Uncertainty Where Certainty is Needed and How to Fight It
“Sometimes the grass is greener on the other side because it’s fake.”
-Unknown
Overall, 2025 has been an interesting year as Q1 comes to a close. We have seen very drastic changes to some of the seminal institutions that fund research, check the safety of food, medications, drinking water, and make recommendations regarding global health, immunizations, and other critical health infrastructure. To wit, we are seeing the levying of tariffs the likes of which have not been seen since the Smoot-Hawley act of 1930 with an uncertain outcome to average people (I.e. our patients) and to some of our businesses.
It seems difficult to calibrate given the rapid rate of changes. My mom, who has a 401k, takes social security, has Medicare, and is on disability due to severe mobility issues from a near-death illness in 2019, has survived a 90% chance of dying. She is not completely aware of things, and views the world through the lens of conversations with my brother and myself, and of course, infomercials. She relies on income and medical care from things that a lot of us used to count on. My son, a precocious 12-year-old, has expressed concerns about affording basic things given what some are predicting will be a very rough next few years from a fiscal standpoint. Many of my friends, like me, are knocking on the half century mark, are not investing, not saving, and using their income to park in other places than the market.
Medicare, its recipients, and physicians who take Medicare are still waiting for Godot. We have not seen relief from the Medicare cuts “the Doc Fix,” that Congress was considering, because it wasn’t put into the budget. Now, we have a new head of CMS, former cardiothoracic surgeon Dr. Mehmet Oz. Many neurosurgeons have celebrated his nomination, as his brother-in-law is a neurosurgeon.
So far, Dr. Oz has been consistently championing Medicare Advantage, which most of us have seen is essentially privatized Medicare. We have seen skyrocketing denials, increased clawbacks, and several investigations that found the publicly traded companies found guilty of upcoming diagnoses and essentially grifting billions from the government in subsidies, then turning around and denying care to patients. Strange, considering the current initiative within the administration is fighting graft, overspending, and fraud that we would want to keep funding such a venture. With the recent $25 billion dollar pay bump, and no Medicare doc-fix in sight, one wonders how many “free-market” types are questioning if the current administration is intent on fixing anything regarding the healthcare system at all.
Where does this leave surgeons in private practice is key to planning viability in the near and medium term. We have found ways to keep going, by forming alliances, merging practices, finding new revenue streams, and staying diversified in what we do to stay open. We have learned that in being honest with ourselves is important to continuing to operate our businesses. In my own practice, I have learned advocacy is local. A multitude of trips to DC have been a lot of fun, and learned a lot about the echo chambers of Congress. In fact, I had a sitting senator tell me back the exact story I told him about a patient’s misadventures with Medicare Advantage. In fact, he persisted in continuing to tell me the story even after I politely told him a second time. The most recent efforts in DC have yielded a group of lawmakers who seem to think that because most physicians are still taking Medicare, that they don’t care about Medicare cuts, and further – that the rate cutting has not led to consolidation.
Many of the true believers among us will react predictably- “that’s not true, they understand – it’s the fault of _____” , “things are going to get better because they will eventually do the right thing.” I think we have learned that from double digit cuts in Medicare reimbursement, the clock of an inflationary adjustment for Medicare rates, and not even a cost-of-living adjustment (COLA) for Medicare since its inception that no one is coming to save us.
There are things we can do in our own practices if lawmakers cannot help us.
For starters, since Medicare represents many of our practices, considering becoming a non-par provider for Medicare is an option. In that sense, one can take a little less from Medicare, but patients are responsible for a greater amount. This is a tricky balance to strike and it really relies on your abilities to first, navigate the Byzantine halls of Medicare to get that status and to of course, notify your patients of the change. Many will balk at even paying a little, and obviously you will have to have that talk with them and be understanding. For some, especially with inflation and the diminishment of their retirement accounts may be especially want to spend anything extra. Therefore, you have to be ready for that hit.
Completely opting out of Medicare is an option for some, but a drastic and sometimes terrifying step. Dropping Medicare altogether might look attractive to some, while there is still that option. This requires especially difficult navigation, extra forms, contracts and very difficult conversations with patients. For many of us, that is just not a viable option. And imagine the Byzantine halls of Medicare but now with a candle instead of a flashlight. Some will also pepper in that it’s an immoral option. I would argue if it is between staying open and not staying open, all cards are on the table.
Some surgeons add in extra fees, such as cancellations, booking fees, extra charges for services like excessively large amounts of records. Again, transparency is key in keeping patient trust and to make sure collections are done properly, at the time of service, and fairly. Charges like these are not covered benefits of Medicare, but there is most certainly a need to discuss with local and state medical societies to make sure you are coloring within the lines.
As private practice surgeons, we have been through numerous administrations, and this one is not any different in terms of the ineffectiveness of fixing our healthcare system unless they decide to shore up traditional Medicare.
There are several other key issues to focus in on the next few years: site neutrality, physician-owned hospitals, and scope of practice. But being realistic in our advocacy on changing these issues is important to keep our collective sanity. We see decisions made in DC and the state level that we know makes no sense and may actually hurt us. Defunding and privatizing Medicare will not save it, any more than setting a house on fire will get rid of the termites infesting it.
The California Association of Neurological Surgeons would like to thank all of exhibitors in helping making our annual meeting a success!
We value your presence and hope to have you all next year in Southern California!
Medtronic -Gold Sponsor
Aesculap – Silver Sponsor
Cooperative of American Physicians -Silver Sponsor
Integra LifeSciences-Silver Sponsor
Orthofix -Silver Sponsor
Rosman Search -Silver Sponsor
Surgeons Capitol Management -Silver Sponsor
Ruthless Spine -Board Meeting Presentation
Astura Medical
ATEC Spine
Brainlab, Inc
Carbofix Spine
Cerspedics
Day Surgical Products, Inc
GE Healthcare
Globus
GT Medtech
Johnson & Johnson Medtech
KLS Martin
Leica Microsystems
META Dynamic, Inc
Mitaka USA, Inc
NX Development Corp
Q Surgical
Spineart
Stryker Spine
Surgical Theater
Zap Surgical

CANS President
Cause and Effect


CANS MISSION STATEMENT
To Advocate for the Practice of California Neurosurgery
Benefitting our Patients and Profession


More AI fun for this month’s GOTM, courtesy of our authors of April’s
journal club. Dr. Reeves Smith expressed how humbling it is getting
shown new technology by the college kids, such as Karina. There’s
nothing that will make one feel older faster than new technology…

Cardiac surgeons do big, dangerous cases more often than us neurosurgeons. Clamping someone’s aorta, stopping their heart, cutting it open; now that is hard to beat (pun intended). Cracking a skull, exposing the brain, and gently tugging it out of the way may not be as physiologically challenging to the patient, but we, too, operate in areas where the consequences of a mistake, or simple bad-luck, can be significant. Does that mean that neurosurgical procedures are always “major?”
I had a lady a few weeks ago with an adenocarcinoma metastasis to the brain. It was large, and in the left prefrontal area, and was causing some gait and speech difficulties. She had a relatively young child at home. The family was, understandably, stressed out. Resection was felt to be a good palliative option. She perked up a little on some steroids, so I felt optimistic. Home two days after the procedure, which was entirely uneventful, she skipped into my office two weeks later, off steroids, for her stitches to be removed. She was all smiles; I had even been able to hide the incision behind her hairline. Major surgery, for sure, but the recovery was a piece of cake.
That same week, my wife Cathy had an operation on her foot for plantar fasciitis and a bone spur. At two weeks she was still using a lot of pain killers, and now, over a month later, is hobbling around with quite a bit of pain, especially at the end of the day. I was told that the procedure took about 20 minutes; she was back home from the surgery center two hours after the operation’s completion. The orthopod suggested that it was a minor procedure. One month later, I am still having to walk the dog and make dinner every night. Thank God that I like to walk the dog, and am able to cook. But minor surgery? Perhaps so, but the recovery has been more than a minor inconvenience. These little operations can really set you back.
I do carpal tunnel decompressions. I believe that when I choose the patients well, it is my favorite operation. Easy and quick, with happy patients. I do them in a surgery center, in about half an hour. When I first started practice, I would just use local anesthetic, and do them in a procedure room (not the OR) with just a nurse to make sure I had things like sutures and local. It was Canada. I laughed at the concept of doing such a minor procedure with a general anesthetic, as I had heard was normal practice in the US. But, hubris aside, it is easy to forget that after this minor operation the patient loses the full use of their hand for about a month, which is no minor thing. So, is it really minor surgery? Perhaps for the surgeon (it is the littlest operation that I do), but not necessarily for the patient.
Spine surgery is interesting. The patient experience runs the whole gamut. We all see patients who bounce back from a simple discectomy for radiculopathy in a matter of hours, or days, while others take months to recover when the clinical situation seems to be about the same. Even bigger operations, which definitely hurt more, also produce huge variances in response between individuals.
So how should we differentiate minor surgery from major? Need for hospitalization? Length of the procedure? Expected post-operative trajectory? I think that we look at it more from our perspective than that of the patient. We know which operations are potentially more dangerous. That is important, for sure. What is the risk of being permanently worse? How worse? What about the chance that the patient might not improve, or need further procedures? We also know how much work individual operations entail. Length, complexity, and sheer physical demands on the surgeon all count.
I do a fair bit of endovascular work. Everything is done through a groin catheter. The risk of a clinically significant stroke is around one in a thousand with a simple diagnostic angiogram. Does that disqualify it from being a minor procedure? Maybe. These days we can often get a mechanical thrombectomy for embolic stroke done just a quickly. So, is that a minor or major procedure? That answer is a little easier, as the stakes are higher.
Adjectives are just adjectives. But the words we choose do have importance. I dislike the version of Epic that I have to use as an electronic medical record in the hospital. At the end of every post-op note I am prompted for a patient status rating. The options are binary: either “STABLE” or “CRITICAL.” Now, I do not know about you, but I like to think that all my patients are stable after whatever procedure I have done. But that does not mean that I will not worry about them, even if it was a “minor” operation.


A Predictive Code for Serotonin: Rethinking Value in the Brain
Karina Bilokur, Clinical Psychology Student, UC San Diego
Dr. Alexa (Reeves) Smith, Neurosurgeon, Scripps Health
As a clinical psychology student studying how brain mechanisms shape human emotion and decision-making, I found this paper revolutionary. “A prospective code for value in the serotonin system,” published in Nature in 2025 by Harkin et al., presents a novel functional theory of serotonin anchored in computational neuroscience and backed by robust experimental data. Instead of falling back on outdated metaphors of serotonin as a simple “mood molecule,” this work unveils a more sophisticated and mathematically precise role: serotonin neurons in the dorsal raphe nucleus (DRN) encode a predictive, forward-looking value signal that guides behavior based on near-future expectations.
This model—dubbed the “prospective code for value”—frames DRN serotonin neurons as real-time calculators of expected future rewards. Drawing from temporal difference reinforcement learning models, it shows how organisms learn to maximize cumulative future value rather than merely responding to immediate outcomes. The model’s prospective nature is crucial: it looks forward, beyond present and past. Using a temporal discounting factor (γ), it devalues distant outcomes, with optimal results occurring when γ spans a 1–2 second horizon. Put simply, serotonin neurons integrate and weigh upcoming events within a brief temporal window, adjusting their firing patterns accordingly (Fig. 1).
The work’s strength lies in its fusion of theory and high-resolution in vivo data. The authors used fiber photometry and optogenetically-tagged serotonin neurons in mice to record DRN neural activity during classical Pavlovian conditioning tasks with rewards (water) and punishments (air puffs). After testing multiple competing hypotheses—including those based on salience, uncertainty, reinforcement learning prediction errors, and surprise—none matched the prospective value model’s predictive power.
A key finding supports the new model through serotonin neurons’ asymmetric response to unexpected outcomes. DRN serotonin neurons show strong positive responses to surprising rewards but minimal responses to surprising punishments. While traditional models would predict equal responses to both outcomes, the prospective value model explains this asymmetry by showing how these neurons specifically forecast future reward rather than simply detecting all emotionally significant stimuli.
The prospective value model’s superiority is clear in the numbers. When applied to trial-by-trial neural data, it reduced prediction error by 35% compared to the next best model. This dramatic improvement suggests we’ve finally uncovered a coherent, biologically sound theory of serotonin neurons’ function.
The clinical implications are profound. Many psychiatric disorders—depression, anxiety, PTSD, OCD, and substance use disorders—involve distorted future thinking, whether through chronic negative expectations or diminished ability to envision positive outcomes. If serotonin helps forecast near-future value, then disruptions in this predictive system might explain many affective symptoms. For instance, a person with major depression might struggle to anticipate pleasure not from lack of dopamine, but because their serotonergic system fails to properly value future rewards.
Neurosurgical procedures involving the brainstem, midbrain, or hypothalamic areas—regions rich in serotonergic connections—must account for the broader cognitive and emotional effects of manipulating these networks. By incorporating this computational understanding into surgical planning and post-operative care, surgeons can enhance precision medicine approaches. This enables them to better identify patient-specific patterns of dysfunction and design interventions beyond mere structural correction, leading to improved emotional and behavioral outcomes.
This work advances public understanding of serotonin and mental health as well. Moving past simplistic chemical imbalance theories, it offers a precise mechanism: serotonin as a predictive modulator that calibrates our emotional preparation for future events. This perspective unifies psychiatry, psychology, and neuroscience—potentially reducing stigma while enhancing scientific literacy about mental disorders.
In conclusion, “A prospective code for value in the serotonin system” transcends typical neuroscience research—it bridges computational theory and biological data in ways that could transform our approach to emotional disorders. For everyone in the field, it demonstrates how scientific advances can create meaningful progress in mental health care.
Fig. 1: A predictive model of serotonin neuron activity.

Works Cited
Harkin, Emerson F., et al. “A Prospective Code for Value in the Serotonin System.” Nature (London), 2025, https://doi.org/10.1038/s41586-025-08731-7.
CANS, Annual Meeting
January 16-18, 2026 Oxnard, CA
CSNS Meeting April 24-25 Boston, MA
Any CANS member who is looking for a new associate/partner/PA/NP or who is looking for a position (all California neurosurgery residents are CANS members and get this newsletter) is free to submit a 150 word summary of a position available or of one’s qualifications for a two month posting in this newsletter. Submit your text to the CANS editorial office by emailing Anthony.digiorgio@ucsf.edu
Newsletter Editor
Anthony DiGiorgio, D.O.
Contributing Editors
Deborah C. Henry, M.D.
Brian Gantwerker, M.D.
Ian Ross, M.D.
This newsletter is published monthly from the Executive Office:
California Association of
Neurological Surgeons
5380 Elvas Avenue
Suite 215
Sacramento, CA 95819
Tel 916 457-2267
Fax 916 457-8202
www.cans1.org
CANS Board of Directors
| President | Samer Ghostine, MD | Los Angeles |
| President-Elect | Brian Gantwerker, MD | Santa Monica |
| Vice-Pres | Anthony DiGiorgio, DO | San Francisco |
| Secretary | Odette Harris, MD | Stanford |
| Treasurer | Sanjay Dhall, MD | Los Angeles |
| Imd Past Pres | Ciara Harraher, MD | Santa Cruz |
| Past President | Joseph Chen, MD | Bakersfield |
Directors — Northern CA
| Marco Lee, MD | Stanford |
| Eze Goldschmidt, MD | San Francisco |
| Leslie Robinson, MD | Chico |
| Sherry Taylor, MD | Fairfield |
Directors — Southern CA
| Garni Barkhoudarian, MD | Santa Monica |
| Linda Liau, MD | Los Angeles |
| Ian Ross, MD | Pasadena |
| N. Nicole Moayeri, MD | Santa Barbara |
Resident Board Consultants
| James Brazdzionis, DO | RUHS |
| Jessica Campos, MD | UCI |
| Jose Castillo, MD | UCD |
| Alex Lopez, MD | UCI |
Executive Secretary
| Emily Schile | Sacramento | emily@cans1.org |