Limited Midline Myelotomy for Intractable Visceral Pain: Surgical Techniques and Outcomes

Case report: MR-guided laser induced thermal therapy for palliative cingulotomy

In end-stage cancer, oncologic pain refractory to medical management significantly reduces patients' quality of life. In recent years, ablative surgery has seen a resurgence in treating diffuse and focal cancer pain in terminal patients. The anterior cingulate gyrus has been a key focus as it plays a role in the cognitive and emotional processing of pain. While radiofrequency ablation of the dorsal anterior cingulate is well described for treating cancer pain, MRI-guided laser-induced thermal therapy (LITT) is novel. Our paper describes a patient treated with an MRI-guided LITT therapy of the anterior cingulate gyrus for intractable debilitating pain secondary to terminal metastatic cancer.

Ablation Procedures

Although ablation has a limited role in the management of chronic noncancer pain, ablation continues to help patients with treatment of refractory cancer-related pain. Interdisciplinary treatment involving supportive care, pain medicine, oncology, and neurosurgery is critical to optimizing the timing and outcome of neurosurgical ablative options for pain management. In this review, 3 targets for ablative surgery-the spinothalamic tract, the dorsal column's visceral pain pathway, and the anterior cingulate cortex-are discussed with a focus on patient selection and key aspects of surgical technique.

Managing Pain and Discomfort in Children with Cancer

PURPOSE OF REVIEW

Approximately 15,600 children are diagnosed with cancer annually. Many of these children have cancer-related pain that improves with cancer treatment, but some develop intractable pain from cancer progression or sequelae from treatment modalities. The purpose of this paper is to provide a critical evaluation of the literature relevant to pain management in children with cancer. We intend to emphasize important and up-to-date findings in pharmacology, interventional pain management, and complementary and alternative medicine.

RECENT FINDINGS

Alternative medications and routes of administration, complementary and alternative medicine techniques, and interventional pain procedures offer possible routes for a multi-pronged pediatric cancer pain management plan, although high-level data is often lacking. To improve pediatric cancer pain management, a multifaceted approach embracing the biopsychosocial model of pain is recommended, incorporating evidence-based pharmacology, complementary and alternative medicine techniques, and if needed, interventional pain procedures.

Punctate Midline Myelotomy: A Historical Overview and Case Series with Detailed Efficacy and Side Effect Profiles

OBJECTIVE

To review our experience with punctate midline myelotomy (PMM) for malignant and benign visceral pain with an emphasis on detailed side-effect profiles and efficacy.

METHODS

Thirteen adults (5 men) underwent microsurgical transverse-crush PMM.

RESULTS

Median follow-up for the benign pain group (n = 6) was 17.5 months (10-72) and for the malignant group (n = 7) was 8 months (0.5-31). Five of seven patients in the malignant pain group obtained excellent, lasting relief. Two had initial relief followed by worsening pain with disease progression. In the benign pain group, two patients with endodermal-origin pain (gastrointestinal tract, bladder) had complete, long-lasting relief. Three patients with mesodermal-origin pain (ureter) had excellent relief for 2-3 months, followed by recurrence in two and partial (40%) recurrence in the third. One man with pre-existing cervical myelopathy underwent PMM for benign testicular-region pain from which he had long-term relief but only transient relief of coexisting low-back and leg pain. There were no motor deficits in either group, and all patients remained ambulatory and continent. The most common side effect was transient numbness of the medial leg and foot. Two patients (both with pre-existing spinal pathology) reported persistent moderate reduction of bowel, bladder, and sexual sensation.

CONCLUSIONS

PMM offers substantial pain relief for carefully selected patients with intractable visceral pain. Relief from primarily endoderm-derived structures was most complete and long-lasting. Relief from mesoderm-derived structures was typically transient or incomplete. There was essentially no relief from pain of ectoderm-derived structures. Detailed preoperative counseling is important, especially for those with pre-existing neurologic deficits.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Neuroablative Procedures for Patients With Cancer Pain

BACKGROUND

Managing cancer pain once it is refractory to conventional treatment continues to challenge caregivers committed to serving those who are suffering from a malignancy. Although neuromodulation has a role in the treatment of cancer pain for some patients, these therapies may not be suitable for all patients. Therefore, neuroablative procedures, which were once a mainstay in treating intractable cancer pain, are again on the rise. This guideline serves as a systematic review of the literature of the outcomes following neuroablative procedures.

OBJECTIVE

To establish clinical practice guidelines for the use of neuroablative procedures to treat patients with cancer pain.

METHODS

A systematic review of neuroablative procedures used to treat patients with cancer pain from 1980 to April 2019 was performed using the United States National Library of Medicine PubMed database, EMBASE, and Cochrane CENTRAL. After inclusion criteria were established, full text articles that met the inclusion criteria were reviewed by 2 members of the task force and the quality of the evidence was graded.

RESULTS

In total, 14 646 relevant abstracts were identified by the literature search, from which 189 met initial screening criteria. After full text review, 58 of the 189 articles were included and subdivided into 4 different clinical scenarios. These include unilateral somatic nociceptive/neuropathic body cancer pain, craniofacial cancer pain, midline subdiaphragmatic visceral cancer pain, and disseminated cancer pain. Class II and III evidence was available for these 4 clinical scenarios. Level III recommendations were developed for the use of neuroablative procedures to treat patients with cancer pain.

CONCLUSION

Neuroablative procedures may be an option for treating patients with refractory cancer pain. Serious adverse events were reported in some studies, but were relatively uncommon. Improved imaging, refinements in technique and the availability of new lesioning modalities may minimize the risks of neuroablation even further.The full guidelines can be accessed at https://www.cns.org/guidelines/browse-guidelines-detail/guidelines-on-neuroablative-procedures-patients-wi.

Percutaneous Cordotomy for Pain Palliation in Advanced Cancer: A Randomized Clinical Trial Study Protocol

BACKGROUND

Cancer pain, one of the most common symptoms for patients with advanced cancer, is often refractory to maximal medical therapy. A controlled clinical trial is needed to provide definitive evidence to support the use of ablative procedures such as cordotomy for patients with medically refractory cancer pain.

OBJECTIVE

To assess the efficacy of cordotomy for patients with unilateral advanced cancer pain using a controlled clinical trial study design. The secondary objectives are to define the patient experience of cordotomy for medically refractory cancer pain as well as to determine the utility of magnetic resonance imaging as a non-invasive biomarker for successful cordotomy.

METHODS

We will undertake a single-institution, double-blind, sham-controlled clinical trial of cordotomy in patients with refractory cancer pain. Patients in the cordotomy arm will undergo a percutaneous computed tomography-guided cordotomy at C1-C2, while patients in the control arm will undergo a similar procedure where the needle will not penetrate the thecal sac. The primary endpoint will be the reduction in pain intensity, as measured by the Edmonton Symptoms Assessment Scale.

EXPECTED OUTCOMES

We expect that patients randomized to cordotomy will have a significantly greater reduction in pain intensity than those patients randomized to the control surgical intervention.

DISCUSSION

This randomized clinical trial comparing cordotomy with a control intervention will provide the level of evidence necessary to determine whether cordotomy should be the standard of care intervention for patients with advanced cancer pain.

Neuroablative surgical treatments for pain due to cancer

Cancer pain is common and challenging to manage - it is estimated that approximately 30% of cancer patients have pain that is not adequately controlled by analgesia. This paper discusses safe and effective neuroablative treatment options for refractory cancer pain. Current management of cancer pain predominantly focuses on the use of medications, resulting in a relative loss of knowledge of these surgical techniques and the erosion of the skills required to perform them. Here, we review surgical methods of modulating various points of the neural axis with the aim to expand the knowledge base of those managing cancer pain. Integration of neuroablative approaches may lead to higher rates of pain relief, and the opportunity to dose reduce analgesic agents with potential deleterious side effects. With an ever-increasing population of cancer patients, it is essential that neurosurgeons maintain or train in these techniques in tandem with the oncological multi-disciplinary team.

Spinal Cord Stimulation for Visceral Pain: Present Approaches and Future Strategies

INTRODUCTION

The introduction of successful neuromodulation strategies for managing chronic visceral pain lag behind what is now treatment of choice in refractory chronic back and extremity pain for many providers in the United States and Europe. Changes in public policy and monetary support to identify nonopioid treatments for chronic pain have sparked interest in alternative options. In this review, we discuss the scope of spinal cord stimulation (SCS) for visceral pain, its limitations, and the potential role for new intradural devices of the type that we are developing in our laboratories, which may be able to overcome existing challenges.

METHODS

A review of the available literature relevant to this topic was performed, with particular focus on the pertinent neuroanatomy and uses of spinal cord stimulation systems in the treatment of malignant and nonmalignant gastrointestinal, genitourinary, and chronic pelvic pain.

RESULTS

To date, there have been multiple off-label reports testing SCS for refractory gastrointestinal and genitourinary conditions. Though some findings have been favorable for these organs and systems, there is insufficient evidence to make this practice routine. The unique configuration and layout of the pelvic pain pathways may not be ideally treated using traditional SCS implantation techniques, and intradural stimulation may be a viable alternative.

CONCLUSIONS

Despite the prevalence of visceral pain, the application of neuromodulation therapies, a standard approach for other painful conditions, has received far too little attention, despite promising outcomes from uncontrolled trials. Detailed descriptions of visceral pain pathways may offer several clues that could be used to implement devices tailored to this unique anatomy.

Limited midline myelotomy for visceral pain

The traditional commissural myelotomy consists of a sagittal cut in the midline and was originally described by Greenfield and performed by Armour in 1926. Today, myelotomy refers to the selective disruption of the ascending visceral pain pathway. The success of the procedure is incumbent on the correct identification of the midline. Limited midline open myelotomy for the treatment of medically intractable abdominal or pelvic visceral cancer pain, with the aid of somatosensory evoked potentials to identify midline, offers patients superior pain relief over similar percutaneous techniques. Multicenter registries are needed to better elucidate the best surgical technique for this procedure.

The video can be found here: https://youtu.be/0unlmwp08po

Neurosurgical ablative procedures for intractable cancer pain

OBJECTIVE

Cancer patients suffering from severe refractory pain may benefit from targeted ablative neurosurgical procedures aimed to disconnect pain pathways in the spinal cord or the brain. These patients often present with a plethora of medical problems requiring careful consideration before surgical interventions. The authors present their experience at an interdisciplinary clinic aimed to facilitate appropriate patient selection for neurosurgical procedures, and the outcome of these interventions.

METHODS

This study was a retrospective review of all patients who underwent neurosurgical interventions for cancer pain in the authors' hospital between March 2015 and April 2018. All patients had advanced metastatic cancer with limited life expectancy and suffered from intractable oncological pain.

RESULTS

Sixty patients underwent surgery during the study period. Forty-three patients with localized pain underwent disconnection of the spinal pain pathways: 34 percutaneous-cervical and 5 open-thoracic cordotomies, 2 stereotactic mesencephalotomies, and 2 midline myelotomies. Thirty-nine of 42 patients (93%) who completed these procedures had excellent immediate postoperative pain relief. At 1 month the improvement was maintained in 30/36 patients (83%) available for follow-up. There was 1 case of hemiparesis.Twenty patients with diffuse pain underwent stereotactic cingulotomy. Nineteen of these patients reported substantial pain relief immediately after the operation. At 1 month good pain relief was maintained in 13/17 patients (76%) available for follow-up, and good pain relief was also found at 3 months in 7/11 patients (64%). There was no major morbidity or mortality.

CONCLUSIONS

With careful patient selection and tailoring of the appropriate procedure to the patient's pain syndrome, the authors' experience indicates that neurosurgical procedures are safe and effective in alleviating suffering in patients with intractable cancer pain.

Interventional Techniques to Management of Cancer-Related Pain: Clinical and Critical Aspects

Interventional techniques to manage cancer-related pain may be efficient treatment modalities in patients unresponsive or unable to tolerate systemic opioids. However, indication and selection of the right technique demand knowledge, which is still incipient among clinicians. The present article summarizes the current evidence regarding the five most essential groups of interventional techniques to treat cancer-related pain: Neuraxial analgesia, minimally invasive procedures for vertebral pain, sympathetic blocks for abdominal cancer pain, peripheral nerve blocks, and percutaneous cordotomy. Furthermore, indication, mechanism, drug agents, contraindications, and complications of the main techniques of each group are discussed.