I am looking to learn more about the possible psychiatric (not felt) symptoms of a Chiari I malformation. There is very little easily accessible information about this, but one thing I’ve observed is that people who seem to have psychiatric manifestations (e.g. the presentation of bipolar disorder) often do not have comorbid, classic physical symptoms. Any thoughts? Are you aware of researchers, neurologists or neurosurgeons who know how this malformation might manifest as psychiatric illness or other cognitive issues? Do you know of any experts in CM? If so, I’d like to try contacting them.
A physical therapist friend I am discussing this with has these additional questions:
Severity of symptoms with Chiari is not actually correlative to the degree of extension beyond the foramen magnum. So what actually causes the symptoms? The pressure on the brain regions? Or the decrease in the flow of CSF?
How do we measure either the pressure in that area or the CSF flow? Could CSF flow be measured using relatively non-invasive and inexpensive techniques, like doppler?
Are there non-invasive treatments (physical therapy treatments, for example) that could decompress the area or improve CSF flow?
Could epidural injections in the area (like those that are performed for herniated discs in the spine to relieve symptoms due to pressure on individual spinal nerves) potentially decompress the CM?
Would a person with Chiari-related psychiatric problems respond well to psychiatric interventions, or would symptoms persist?
Hello, I can help answer some of your questions. As a nuclear trained neuropsychiatrist who is trained in functional brain imaging, neuroscience, and molecular medicine, I can partially help; especially with questions 1 and 5. Individual psychiatric and neurology studies on this topic will probably not be as high yield as looking through the lens of what I call “functional cerebrology” (i.e., using functional parcellations, neuroscience principles from connectomics and molecular medicine we can estimate the type of symptoms someone may have just by looking at what we call the “connectivity” of the regions affected. Unfortunately, it is rare for a neurologist, neurosurgeon, or psychiatrist to have this knowledge (I practice in a very niche area); and neuroscientists aren’t physicians so they don’t treat patients. I have seen Chiari cases more than once using functional brain imaging that present with a whole host of symptoms (cognitive, psychiatric, physical). And the symptoms make sense if you take into account the brain’s connections and how the brain creates meaning and pain/experience. First of all, in CM the cerebellar tonsils herniate through the foramen magnum, but this also causes bottom of the cerebellum to press against the lower portions of the skull near the foramen magnum. Compression here can affect any network in the brain with connections to the inferior cerebellum (i.e., the dorsal and ventral attention networks, somatomotor and limbic networks, frontoparietal - much less of the default mode (DMN) and visual networks (VN), etc) and thus cause psychiatric symptoms associated with those networks. Thus, in CM you are less likely to see depression caused by rumination/obsession over negative thoughts/beliefs (like a record playing over and over) and more likely to see anhedonia/avolition depression (e.g., difficulty finding the energy to get up and move, loss of all interest, flat facial expressions, mood swings, memory difficulties, etc). You are also more likely to get attentional difficulties and executive impairments, including loss of top/down control of limbic symptoms, which as you pointed out may lead to increased likelihood of mood swings as seen in bipolar like illness (and this fits with neuroscience models of bipolar DO). I have seen CM patients who had functional brain scans that fit this model quite well. In theory, anything that lessens the downward pressure on the cerebellum could help improve those psychiatric symptoms (e.g. surgery or other treatments). However, I am not a surgeon and therefore not qualified to say whether fixing CM leads to improved psychiatric symptoms in practice (and I’m not sure if they would know - if they even ask about those symptoms or focus mostly on physical symptoms). In terms of answering question #5, in my experience the answer is “it depends”. Without examining you I can’t give you medical advice. However, in principle our brain creates physical and mental experiences in a holistic way. This means that even if the problem isn’t caused by one brain region, improving it might still help because it may be connected to a network that can improve or help you cope with certain symptoms. Additionally, if we give psychiatric medications that happen to improve activity in the regions that are impaired, it may help alleviate CM related physical AND psychiatric symptoms even if we don’t fix the main cause (I have seen this happen before). However, since we aren’t fixing the main source of the problem in that case, it is possible the treatment will not be as optimal as fixing the CM/CSF flow problems. I hope that helps. If you are still in need of help, I specialize in the interaction of neuroscience/brain conditions and psychiatric issues (including CM) and I’d be happy to talk to you briefly to see if I can help. You can email me at aaron.k.andersen.do@protonmail.com Good luck!