In preparation for a Tweetchat I am guest hosting on this topic for Pallimed, A Hospice and Palliative Medicine Blog (#hpm), I decided to put together this short summary of what neurosurgery has to offer for the palliative care of suffering patients. Links to references and other resources are at the bottom.
There are three major ways that neurosurgery can alleviate pain:
1. Targeted Drug Delivery in which medication is delivered directly to the brain or spinal cord by way of a very small catheter placed in the spinal fluid. The catheter could be connected to a pump placed under the skin for longer term use. Alternatively, a procedure not much bigger than a spinal tap can be used to place the catheter and bring it out through the skin to an external pump.
When patients require doses of opioids and other medications that give them unacceptable side-effects, like clouding of consciousness, lethargy, loss of appetite, severe constipation, targeted drug delivery can often allow caregivers to reduce or even eliminate such medications, resulting in an improved quality of life and often better pain control.
2. Neurostimulation is the use of electrical stimulation, through small electrodes placed via needle or small incision, to reduce pain. It is especially effective with neuropathic pain (the pain caused by an injured or damaged nerve that sends erroneous signals to the brain causing the perception of burning, itching ,swelling or other kinds of pain). One can stimulate a peripheral nerve, the spinal cord or even the brain (“deep brain stimulation”) to achieve pain control, depending on the circumstances.
Often neurostimulation is not considered in the context of palliative care. But, in such a setting, neuropathic pain can be difficult to address. It is possible to place a neurostimulation lead under the skin and bring it out to an external control (pulse generator). In this way, hard-to-control pain (e.g., after radiation, chemotherapy or the surgical injury of a nerve) can often be addressed without the additional incision and expense of an implanted pulse generator (as is used in non-palliative care settings).
3. Neuroablation is the interruption of certain pain pathways in the brain or spinal cord to achieve pain control. These can be very effective and often will allow the patient to drastically decrease or even eliminate the pain medication s/he is taking. There are a number of such procedures available, depending on the details of the pain. Percutaneous cordotomy, myelotomy and nucleotractotomy are outpatient, CT-guided procedures, done under local anesthesia through a needle, that interrupt the pain pathways for different locations. There are links to brochures below.
Cingulotomy is a procedure done under brief general anesthesia in which a computer is used to target two areas of the brain to interrupt pathways related to suffering. It can be very effective in treating the “suffering” component of pain. Recently, it was found to be effective in treating the air hunger associated with a lung tumor in a case report (see reference here).
Radiosurgical hypophesectomy is a non-invasive, single visit, outpatient procedure targeting the pituitary gland (hypophysis). It is based on decades of experience with surgically removing the pituitary gland for diffuse pain from bone metastases (cancer that has traveled to the bone). No one knows how it works, but it can be very effective. And, since it is completely non-invasive, the risks are very low. Even pituitary function is usually preserved and, if it is affected, hormones can easily be replaced.
References and Resources
A randomized, multicenter trial of targeted drug delivery for cancer pain – this does not, however, address an externalized catheter for palliative care
Intrathecal Drug Delivery for the Management of Cancer Pain: A Multidisciplinary Consensus of Best Clinical Practices
Here is a good review of neuroablation procedures: Destructive Procedures for the Control of Cancer Pain
A case series of radiosurgical hypophysectomy for cancer pain
Patient Resource is a great resource for cancer-related information. Their Cancer Guide has a good overview of pain control inside. In addition, the Cancer Pain Research Consortium is working with them to produce a guide to controlling cancer pain.(Disclosure: I am on their National Advisory Board.)
Dr. Rosenberg, in collaboration with colleagues at University of Michigan and University of Texas MD Anderson Cancer Center, has published an article in Pain Medicine reporting a series of cancer patients whose pain was successfully treated by both intrathecal drug delivery (a “pain pump”) as well as modification of the pain processing system in the central nervous system through cordotomy or myelotomy. This study is important in illustrating the potential for overall pain control and improvement in quality of life by using a “toolbox” approach, in which all different clinical “tools” are considered and used. This can be far superior to the limited list of possibilities that is usually considered in treating cancer-related pain, both in terms of pain control and limiting the effects of pain medications (tiredness, nausea and vomiting, loss of appetite, etc.)
It is important for every cancer patient to realize that pain is not a necessary consequence of having cancer. The health care provider who is caring for the patient should continuous consider new options for pain control, sometimes revisiting options that had been previously ruled out. In addition, cancer patients who are in pain should expect their health care provider to work toward effective pain control WITHOUT unacceptable side effects. While this is not always achievable, it often is – if a “big toolbox” is used.
While on faculty at a cancer pain meeting, Dr. Rosenberg encountered a new technology (Calmare nerve stimulation) claiming to address neuropathic pain using skin-based stimulation done in an office setting. Initially, he was very dubious, but one of the presentations in the meeting came from a senior researcher at the Mayo Clinic who demonstrated efficacy using the device with chemotherapy-induced neuropathy in a randomized, blinded study. This prompted him to try it himself and the short-term results were actually very remarkable.
Therefore, the Center decided to evaluate the technology for use in the office. We are currently treating a number of patients for the minimum 10 treatments and following the results. If they look encouraging, we will consider getting the device for use in the office. We will keep you posted as to the results.
Dr. Rosenberg was recently appointed to the Education Committee of the American Society for Stereotactic and Functional Neurosurgery. The ASSFN is also the AANS/CNS Joint Section on Stereotactic and Functional Neurosurgery. The Committee’s first task is to review resident education requirements for functional neurosurgery. Dr. Rosenberg will be assisting in evaluating these requirements regarding the neurosurgical treatment of pain.
A young woman was referred for severe upper neck pain with a rare disorder that causes abnormal bone absorption. This had eroded the upper two cervical vertebrae and the clivus (upper neck and base of the skull). Her spine was probably not stable and she had severe (8-9/10) pain despite taking the equivalent of 30 milligrams of morphine every day.
As an outpatient, we took her to the CT scanner and, under general anesthesia, were able to fill the open bone spaces, including the clivus at the base of the skull, with bone cement. This was done with a large needle through the back of the mouth (pharynx). There was no incision to heal and she was discharged the next morning.
We just saw her back in follow-up. She has had no pain (0/10) since the time of the procedure. She is on no pain medication and has resumed all normal activities.
Although vertebroplasties (filling the vertebrae of the spine with bone cement) have been done for years, as far as we can tell, this is the first time a “clivoplasty” has been performed. We are also able to perform C-1 and C-2 vertebroplasties using a transoral, percutaneous, CT-guided approach.
There are good data showing that the current over-emphasis on “rules” for clinical decision-making is not resulting in improvement in care. While some rules are helpful, even necessary, clinical medicine is too complex and “fuzzy” to rely on them. This is the problem with our current regulatory environment – the belief that medicine can be reduced to a set of instructions, which, if followed, will result in good care. In fact, for all but a few situations, good clinical judgement and experience is what is needed. And that cannot be distilled down to an list or guidelines. It’s hard enough to teach and really must be acquired over years of experience.
There are few areas of medicine in which this is more apparent than pain care. Pain is intrinsically difficult to understand and diagnose. Although the government and insurance industry are trying to simplify this care into a list of rules, it is not working. And people are suffering from the effort. What is needed is to foster interdisciplinary collaboration, help clinicians gain and share experience while keeping an open mind and remaining centered on the individual patient.
Stephanie had severe, debilitating, daily migraines for 16 years and tried numerous treatments without benefit. A peripheral neurostimulator (with leads just under the skin) gave her 80% relief and has allowed her to resume her life. She contacted Fox 4 News with the story and they decided to pursue it.
Another success story. Patient with cancer pain on TD fentanyl and oxycodone yet still in pain had an intrathecal pump placed and reports no cancer pain! Since Dr. Rosenberg started giving a substantial bolus dose of IT medication when pump is place, patients have noted immediate benefit and pain is better managed from the start.