It involves a series of evaluations, procedures, and consultations before and after the actual operation, so people interested in being treated with DBS should be prepared to commit time to the process. For example, those who do not live close to a medical center that offers DBS surgery may need to spend significant time traveling back and forth to appointments.
Prospective patients should have realistic expectations about DBS results. Patients with symptoms that respond well to medications but who, when the drugs wear off, experience severe motor fluctuations and dyskinesias, despite medication adjustments. Patients whose movement symptoms might respond to higher or more frequent medication doses, but who are limited to do so because of side effects. Essential tremor is the most common movement disorder, and DBS can be an effective therapy, particularly in severe cases where the shaking can be disabling, limiting everyday tasks such as dressing, shaving, eating or drinking.
Since tremor is the only symptom in essential tremor, DBS can improve life for people with the condition and help them function normally. Dystonia is a relatively uncommon movement disorder, but its symptoms — abnormal postures and twisting movements — can respond to DBS when medications fail to provide adequate relief. Some recent studies have suggested that people living with depression , obsessive-compulsive disorder OCD or Tourette disorder may benefit from DBS surgery. More research is needed to determine if DBS is effective in treating psychiatric disorders and if any benefits outweigh risks and side effects.
Talking with a neurologist who specializes in movement disorders can determine if an individual is a good candidate for DBS. Continued good response to PD medications, even if the medication effects may wear off sooner than they have in the past. A history of several different combinations of PD medications while under the supervision of a neurologist specializing in movement disorders. A psychiatric condition such as depression or anxiety that has not improved or stabilized with other treatment. Having one or more does not disqualify a person for future DBS surgery, but the doctor may recommend more aggressive therapy focused on these issues before surgery takes place.
To accomplish these two objectives, the movement disorders neurologist will examine the patient in the absence of his or her PD medications, then again after having taken them. Seeing the effect of PD medications on the movement and non-motor symptoms helps the physician and patient identify good target symptoms for DBS. This assessment also informs the team of the risk of having worsened confusion or cognitive problems following the procedure.
Some hospitals also perform an occupational therapy review or speech, language and swallowing assessment. A psychiatrist may examine the person to determine if a condition such as depression or anxiety requires treatment before the DBS procedure. In some cases the surgeon will insert both the lead and the neurostimulator; in other instances the two surgeries may be performed separately, with the neurostimulator implanted days or weeks after the lead is placed. Stereotactic DBS surgery requires the patient to be off their medication.
During the procedure, a frame stabilizes the head and provides coordinates to help the surgeons guide the lead to the correct location in the brain. The patient gets local anesthesia numbing medicine to keep them comfortable throughout each step along with a mild sedative to help them relax.
- Philosophy Without Women: The Birth of Sexism in Western Thought (Athlone Contemporary European Thinkers Series).
- Navigation menu.
During image-guided DBS surgery, such as with interventional MRI iMRI or CT scan, the patient is often asleep under general anesthesia while the surgeon uses images of the brain to guide the lead to its target. In this case, the doctor and patient will discuss which procedure is better based on a number of factors. For instance, the doctor may recommend an image-guided procedure for children, patients who have extreme symptoms, those who are especially anxious or fearful or those whose leads are going into certain parts of the brain. After shaving a small amount of hair behind the hairline, the surgery team injects local anesthesia numbing medication into the scalp for placement of the head frame.
Federated Search Page Form block
After more numbing medication, the neurosurgeon drills a small hole in the skull to insert the lead. The team records the process as the lead moves through the brain tissue to ensure accurate placement of the lead. The person may be asked to move the face, arm or leg at certain times while the recordings are being taken.
Once the lead is in position it is attached to an external neurostimulator. Electrical stimulation administered through the lead for a short period helps the doctors see if symptoms improve or if side effects such as muscle contractions or visual phenomena appear. An extension wire is attached to the lead and placed under the scalp, connecting the lead to the neurostimulator.
Microelectrode recording MER uses electrical current uA at a very high frequency Hz to precisely identify the surgical site for implantation of the deep brain stimulator DBS. The microelectrode allows the surgical team to visualize and hear the neuronal activity from different areas of the brain to identify specific structures based on the unique patterns of neuronal activity. The patient needs to be awake not under general anesthesia in order for MER to yield high quality information.
This procedure takes place under general anesthesia so that the person is asleep. The surgical team inserts the neurostimulator under the outer layers of skin, usually just under the collarbone, but sometimes in the chest or abdomen. The extension wire from the lead is attached to the neurostimulator.
Emerging technologies for improved deep brain stimulation
In general, the hospital stay after DBS surgery is 24 hours but it may be longer depending on how quickly the patient recovers and is ready to go home. The doctor will visit, ensure the person is ready to leave and provide instructions for home care.
At home, it is important to keep the incisions clean and dry. The doctor will provide the patient with specifics on how to bathe while the surgical site heals. If there are stitches, these will be removed during a follow-up office visit. Adhesive strips, if present, should be kept dry and generally will fall off within a few days. The patient will be given a magnet that can be used to turn the neurostimulator on or off under conditions prescribed by their doctor. After the DBS lead s and neurostimulator are in place, the patient will return to the doctor to have the neurostimulator programmed for optimal electrical stimulation.
Yet others may become hypersexual and manic. There have been reports of patients who have developed uncharacteristic sexual urges that they feel unable to control. One conservative, mature gentleman began to aggressively insist on sexual gratification every night following DBS treatment. Another report describes a woman who lost all inhibition under DBS, and who began to expose herself to male members of her family, demanding sex.
Other times, changes can be more benign. One patient receiving stimulation to the nucleus accumbens, a part of the forebrain involved in reward and addiction, had not been that much of a music fan prior to DBS treatment. But, under stimulation, he unexpectedly became a devoted fan of the musician Johnny Cash, buying all of his CDs and DVDs, and banning other music that he had previously liked. Supporters of DBS contend that dangerous personality changes, should they occur, can be programmed away or switched off.
They say that the entire DBS system can for some patients be removed with a further neurosurgical procedure. In short, they contend that the damage is reversible. But claims about complete reversibility appear premature. There are also further ethical dilemmas we face in treating patients with intractable disease. How should we decide which patients qualify for a DBS trial? How can we overcome obstacles to obtaining valid informed consent to the procedure? When is the right time to initiate largescale clinical trials, and what sort of trial design strikes the optimal balance between its scientific goals and the protection of patients?
Of course, such questions pertain to other areas of medical research, yet they are particularly salient in DBS trials.
As use of the technology has expanded, it raises the question: when are the side effects, including a new and potentially dangerous personality, worse than the disease? There are also examples where patients and spouses disagree if the individual has changed following treatment, and whether or not the change is beneficial. In aggregate, the studies and interviews raise profound questions about the nature of identity, autonomy and our relationship to medical technology.
But they must be placed in their proper context. DBS has been shown to lead to significant clinical benefits and improved quality of life for large numbers of movement-disorder patients, and it is still unclear how prevalent extreme, disruptive personality change has become. One obstacle to investigating the prevalence is that existing clinical assessment tools are not sufficiently fine-grained to capture all of these effects.
While absence of evidence is evidence of absence, it is crucial that we not overhype these reports, just as it is crucial not to overhype the potential benefits of experimental DBS. A number of other factors could be responsible. The fact that drugs are also associated with personality changes calls into question whether issues raised by DBS are unique. I contend that they are. Consider that the effects of drugs will wane over relatively short periods of time as the drug is metabolised. In contrast, the effects of DBS do not wane in the same manner over the short term.
Is deep brain stimulation for better health worth the risk? | Aeon Essays
Moreover, some effects of stimulation can occur almost immediately. DBS is a far more precise and adjustable method of altering brain activity than pharmacology. While pharmaceutical interventions will affect receptor activity in neurons across the brain, DBS can be used to hone in on much more specific neural targets down to a cubic millimetre of brain tissue , and the parameters of stimulation can be altered to modulate activity in that target in various ways. This degree of precision is important when we consider the effects of DBS on personality in the psychiatric context.
While such changes are unintended in the treatment of movement disorders, the primary purpose of DBS in the psychiatric context might be to change personality, since the aim of treatment could be to alter aberrant emotional and motivational states. A hyperconscientious or obsessive individual, for instance, might see that state of being as consistent with who they are, and not a deficit of personality at all.
It seems undeniable that in some cases patients have been harmed by their behavioural change. Is patient acceptance of any given personality change an important criterion for its benefit — even if the patient making the judgment is influenced by invasive stimulation that keeps the change alive? Recent studies suggest that patients and their carers do, in fact, have a nuanced understanding of the moral implications of these changes, drawing on deeper understandings of their relationships, identities and essential selves. In an article in Plos One in , a group of Dutch researchers interviewed 18 patients with OCD, asking them whether they had changed as a person.
The patients were changed, but often in ways that made them more like themselves.
deep brain stimulation
I needed less time to pause at things, and think about things, so it took less time. The issues here are complex. On the one hand, it is the precision and adjustability of DBS that offers some basis for hoping that it can succeed where drugs have so far failed. On the other, the nature of the changes wrought, and their potentially longterm implications, means that we must take extreme care to get it right. R ather than drawing general ethical conclusions for all personality changes following DBS across all of its applications, we need a moral framework that accounts for the variability of patient experience, case by case.
The framework should help us to answer three questions: what does it mean for a person to change personality? How do we establish that this has happened? Why do such changes matter from a moral stance? Perhaps the most significant moral challenge raised by reports of personality change following DBS is ensuring that future patients are as informed as possible about all the potential negative effects.
A useful framework would invoke broad conceptions of identity and the self. But how can we capture the concept of authenticity?
It is not difficult to imagine how the individuals in such experiments could come to feel deeply alienated from behaviours that they disvalued, but that they nonetheless had been conditioned to enjoy. The thought here is that simply inducing a motivation to eat in a patient for whom low body weight is of paramount importance might be experienced as completely alien to the patient and highly distressing.
In contrast, if stimulation instead serves to reduce compulsive behaviours that the patient disowns, or to modify disordered emotional processing, then changes following treatment might more plausibly be understood as authentic. As the technology progresses, other moral questions will emerge. For instance, how can we distinguish between changes that matter morally from those that do not? Hovering over all these questions is the core issue of reversibility. But brain lesioning has come a long way since the frontal lobotomy — the procedures performed today also use stereotactic apparatus, making them far safer and more precise, and there are far more ethical protections afforded to patients.
Yet even modern brain-lesioning procedures such as anterior cingulotomies, a surgery that cuts part of the brain to treat depression, pain and OCD have a significant downside: their effects, both adverse and beneficial, cannot be reversed. Proponents point out that the adverse effects of DBS can often be circumvented by changing the stimulation parameters, or ceasing stimulation altogether. Naturally, this allows the patient to have far greater control and involvement in the treatment process. Moreover, the broadly reversible nature of DBS also means that it is an invaluable research tool in neurosurgery more broadly, allowing researchers to compare the therapeutic effects of modulating activity in the range of neural targets that might be implicated in a particular disorder.
However, as we learn more about the longterm effects of DBS, doubts about reversibility have emerged. This evidence undoubtedly suggests that it is a mistake to make the overly broad claim that DBS is wholly reversible. One must attend to both the reversible and irreversible effects of the procedure, and then compare their medical and moral significance. Technological advancement might ultimately lead us to safer ground.