Pain surgery
Pain surgery is one of the historic foundations of neurosurgery.
Burchiel and Raslan presented in 2019 a review of contemporary concepts in surgical pain treatment, with reference to past successes and failures, what has been learned as a subspecialty over the past 50 years, as well as a vision for current and future practice. This subspecialty confronts problems of cancer pain, nociceptive pain, and neuropathic pain.
Procedures
CNS narcotic administration: Intrathecal Morphine…
see facet joint injections, epidural steroid injections, nerve blocks (interrupting the flow of pain signals along specific nervous system pathways), neuroaugmentation (including spinal cord stimulation and peripheral nerve stimulation), vertebroplasty, kyphoplasty, nucleoplasty, endoscopic discectomy and implantable drug delivery systems.
See Medically refractory trigeminal neuralgia treatment procedures particular to trigeminal neuralgia.
Techniques for other conditions include:
a) deep brain stimulation: targets include thalamus and periaqueductal or Periaqueductal gray.
2. direct drug administration into the CNS:
a) different routes: spinal, epidural or intrathecal, intraventricular
b) different agents: local anesthetics, narcotics (without motor, sensory, or sympathetic impairment seen with local anesthetics)
3. intracranial ablative procedures:
a) cingulotomy: theoretically reduces the unpleasant a ect of pain without eliminating the pain. Must be done bilaterally, recently with MRI. Intolerable pain usually recurs after ≈ 3 mos. 10– 30% develop flattened affect.
b) medial thalamotomy: no longer used (presented for historical reasons). Controversial. Was used for some for nociceptive cancer pain. Performed stereotactically
c) stereotactic mesencephalotomy: for unilateral head, neck, face and/or UE pain. Use MRI to create lesion 5 mm lateral to sylvian aqueduct at the level of the inferior colliculus. Unlike spinal cordotomy, the lesion is not near any motor tracts. Main complication is diplopia due to in terference with vertical eye movement, often transient
4. spinal ablative surgical procedures
a) cordotomy:
● open
● percutaneous
b) cordectomy
c) commissural myelotomy: for bilateral pain
d) punctate midline myelotomy: for relief of visceral cancer pain
e) dorsal root entry zone lesion
f) dorsal rhizotomy: not useful for large areas of involvement
g) dorsal root ganglionectomy (an extraspinal procedure)
h) sacral cordotomy:for patients with pelvic pain who have colostomy and ileostomy.A ligature is tied around the dural sac below S1 nerve roots
5. sympathectomy: possibly for causalgia major; see Sympathectomy and Complex regional pain syndrome (CRPS)
6. peripheral nerve procedures
a) nerve block:
● neurolytic: injection neurodestructive agents (e.g. phenol or absolute alcohol) on or near the target nerve
● nonneurolytic: using local anesthetics, sometimes in combination with corticosteroids
b) neurectomy: (e.g. intercostal neurectomy for pain due to infiltration of chest wall by malignancy). Performed open or percutaneously with radiofrequency lesion. May sacrifice motor function with mixed nerves
c) peripheral nerve stimulators: rarely discussed.
Noncancer Pain
For noncancer pain, ablative procedures such as DREZ surgery and rhizolysis for trigeminal neuralgia (TN) should continue to be practiced. Other procedures, such as medial thalamotomy, have not been proven effective and require continued study. Dorsal rhizotomy, dorsal root ganglionectomy, and neurotomy should probably be abandoned.
Cancer Pain
For cancer pain, cordotomy is an important and underutilized method for pain control. Intrathecal opiate administration via an implantable system remains an important option for cancer pain management. While there are encouraging results in small case series, cingulotomy, hypophysectomy, and mesencephalotomy deserve further detailed analysis.
Electrical neuromodulation is a rapidly changing discipline, and new methods such as high-frequency spinal cord stimulation (SCS), burst SCS, and dorsal root ganglion stimulation may or may not prove to be more effective than conventional SCS.
Despite a history of failure, deep brain stimulation for pain may yet prove to be an effective therapy for specific pain conditions. Peripheral nerve stimulation for conditions such as occipital neuralgia and trigeminal neuropathic pain remains an option, although the quality of outcomes data is a challenge to these applications. Based on the evidence, motor cortex stimulation should be abandoned. TN is a mainstay of the surgical treatment of pain, particularly as new evidence and insights into TN emerge. Pain surgery will continue to build on this heritage, and restorative procedures will likely find a role in the armamentarium. The challenge for the future will be to acquire higher-level evidence to support the practice of surgical pain management 1).
Non-pharmacologic interventions are often effective in reducing pain in the ED. However, most existing studies are small, warranting further investigation into their use for optimizing ED pain management 2).