A novel lateral myelotomy approach for the treatment of lateral or ventrolateral spinal gliomas.

OBJECTIVE: To describe a novel surgical approach in which myelotomy was performed lateral to the dorsal root entry zone (LDREZ), for the treatment of lateral or ventrolateral spinal intramedullary glioma. METHODS: This study reviewed six patients with lateral or ventrolateral spinal intramedullary glioma who received surgical treatments by using myelotomy technique of LDREZ approach. The patient's clinical characteristics, magnetic resonance imaging (MRI) results, and follow-up outcomes were analyzed. The neurological function of patients before and after operation was assessed based on the Frankel scale system. The anatomical feasibility, surgical techniques, advantages and disadvantages of LDREZ approach were analyzed. RESULTS: Myelotomy technique of LDREZ approach was employed in all 6 patients. Gross total resections were achieved in 4 patients, and 2 patients with astrocytoma (case 2, 6) underwent partial removal. The perioperative recovery was all smooth and all the patients were discharged on schedule. All the patients who suffered from neuropathic pain were relieved. After surgery, neurological function remained unchanged in 3 patients. 2 patients improved from Frankel grade B to C, and 1 patient deteriorated from Frankel grade D to C immediately after surgery and returned to Frankel grade D at 3 months follow-up. Regarding to the poor prognosis of high-grade glioma, the two cases with WHO IV glioma didn't achieve long survival. CONCLUSION: LDREZ approach is feasible and safe for the surgical removal of lateral or ventrolateral spinal gliomas. This approach can provide a direct pathway to lateral or ventrolateral spinal gliomas with minimal damage to normal spinal cord.

Endoscopic assisted microscopic posterior cordotomy for bilateral abductor vocal fold paralysis using radiofrequency versus coblation.

PURPOSE: To assess the outcomes of endoscopic assisted microscopic posterior cordotomy for bilateral abductor vocal fold paralysis (BAVFP) using radiofrequency versus coblation. METHODS: This was a randomized prospective cohort study that carried out on 40 patients with BAVFP who were subjected to endoscopic/assisted microscopic posterior cordotomy. The patients were randomly allocated into two groups: group (A) patients were operated with radiofrequency, and group (B) patients were operated with coblation. Glottic chink, grade of dyspnea, voice handicap index 10 (VHI10), and aspiration were evaluated pre-operatively and 2 weeks and 3 months post-operatively. RESULTS: There was a significant improvement in the glottic chink and VHI10 scores postoperatively with a non-significant difference between both groups regarding the degree of improvement. In addition, there was a significant improvement of the grade of dyspnea with a non-significant impact on the degree of aspiration in both groups post operatively. There was a lower incidence of oedema and granulation formation in the coblation group but without a statistical significance. CONCLUSION: Both techniques are effective alternatives for performing posterior transverse cordotomy in cases of BAVFP.

Effectiveness of CT-guided percutaneous cordotomy in intractable cancer pain: Experience in 14 patients.

BACKGROUND: Severe and treatment-resistant pain is a major issue for patients with cancer. Cordotomy is an effective approach for addressing severe cancer-related pain. It is based on blocking the transmission of pain by damaging the lateral spinothalamic tract. METHODS: Computed tomography guided cordotomy was performed on 14 patients who did not respond to medical and interventional pain management methods. RESULTS: Fourteen patients with cancer pain underwent CT-guided percutaneous cordotomy. Pain relief was reported in 86% of the patients. The visual analog scale values before and after cordotomy were compared and a significant difference was found (p = 0.0001). The improvement in the Karnofsky Performance Scale score of the patients was found to be statistically significant (p = 0.0001). CONCLUSION: We believe that CT-guided cordotomy, performed by experienced hands in a team of experienced individuals and applied to the right patients, is an effective treatment. However, it is crucial to exercise extreme caution regarding potential side effects and serious complications during the cordotomy procedure.

Open thoracic cordotomy for intractable cancer pain: a how I do it.

BACKGROUND: Some cancers of the lower extremity involve nerves and plexuses and can produce extreme drug-resistant noceptive pain. In these cases, open thoracic cordotomy can be proposed. METHOD: This procedure involves disruption of the spinothalamic tract, which sustains nociceptive pathways. After placement in the prone position, selection of the side to be operated on (contralateral to the pain), and dura exposure, microsurgery is used to section the anterolateral spinal cord quadrant previously exposed by gently pulling on the dentate ligament. CONCLUSION: Open thoracic cordotomy is a moderate invasive, safe, and effective option for the management of drug-resistant unilateral lower extremity cancer pain in well-selected patients.

Minimally Invasive Cordotomy for Refractory Cancer Pain: A Randomized Controlled Trial.

BACKGROUND: Up to 30% of patients with cancer continue to suffer from pain despite aggressive supportive care. The present study aimed to determine whether cordotomy can improve cancer pain refractory to interdisciplinary palliative care. MATERIALS AND METHODS: In this randomized controlled trial, we recruited patients with refractory unilateral somatic pain, defined as a pain intensity (PI) ≥4, after more than three palliative care evaluations. Patients were randomized to percutaneous computed tomography-guided cordotomy or continued interdisciplinary palliative care. The primary outcome was 33% improvement in PI at 1 week after cordotomy or study enrollment as measured by the Edmonton Symptom Assessment Scale. RESULTS: Sixteen patients were enrolled (nine female, median age 58 years). Six of seven patients (85.7%) randomized to cordotomy experienced >33% reduction in PI (median preprocedure PI = 7, range 6-10; 1 week after cordotomy median PI = 1, range 0-6; p = .022). Zero of nine patients randomized to palliative care achieved a 33% reduction in PI. Seven patients (77.8%) randomized to palliative care elected to undergo cordotomy after 1 week. All of these patients experienced >33% reduction in PI (median preprocedure PI = 8, range 4-10; 1 week after cordotomy median PI = 0, range 0-1; p = .022). No patients were withdrawn from the study because of adverse effects of the intervention. CONCLUSION: These data support the use of cordotomy for pain refractory to optimal palliative care. The findings of this study justify a large-scale randomized controlled trial of percutaneous cordotomy. IMPLICATIONS FOR PRACTICE: This prospective clinical trial was designed to determine the improvement in pain intensity in patients randomized to either undergo cordotomy or comprehensive palliative care for medically refractory cancer pain. This study shows that cordotomy is effective in reducing pain for medically refractory cancer pain, and these results can be used to design a large-scale comparative randomized controlled trial that could provide the evidence needed to include cordotomy as a treatment modality in the guidelines for cancer pain management.

Neurosurgeons' Armamentarium for the Management of Refractory Postherpetic Neuralgia: A Systematic Literature Review.

BACKGROUND/AIMS: Postherpetic neuralgia (PHN) can be refractory to both medical and minimally invasive treatments. Its complex pathophysiology explains the numerous neurosurgical procedures that have been implemented through the years. Our objective was to summarize all available neurosurgical strategies for the management of resistant PHN and evaluate their respective safety and efficacy outcomes. METHODS: A comprehensive systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: A total of 38 studies comprising 811 patients with refractory PHN were included. The safety and efficacy of the following procedures were investigated: spinal cord stimulation (SCS), dorsal root entry zone (DREZ) lesioning, intrathecal drug delivery, caudalis DREZ lesioning, dorsal root ganglion (DRG) radiofrequency lesioning, peripheral nerve stimulation, gamma knife surgery, deep brain stimulation, cordotomy, percutaneous radiofrequency rhizotomy and Gasserian ganglion stimulation. CONCLUSIONS: There are several available neurosurgical approaches for recalcitrant PHN including neuromodulatory and ablative procedures. It is suggested that patients with resistant PHN undergo minimally invasive procedures first, including SCS, peripheral nerve stimulation or DRG radiofrequency lesioning. More invasive procedures should be reserved for refractory cases. Comparative studies are needed in order to construct a PHN neurosurgical management algorithm.

A comparison of two endoscopic posterior cordotomy techniques: Laser cordotomy vs diathermy-assisted cordotomy.

OBJECTIVES: To compare respiratory function, swallowing and voice quality of bilateral abductor vocal fold paralysis (BAVFP) patients undergoing laser and diathermy-assisted posterior cordotomy. DESIGN: Prospective study. SETTING: Tertiary academic hospital. PARTICIPANTS: Thirty patients were included in the study (groups 1 and 2, 15 patients each). Mean age was 53 ± 14.27 years with a range of 31-78 years (12 [40%] males, 18 [60%] females). MAIN OUTCOME MEASURES: Sufficient airway, complications, FEV1, FEV1/FVC, peak expiratory flow rate (PEF), voice quality VAS, fundamental frequency, jitter, shimmer, NHR, amplitude perturbation quotient (APQ) and pitch perturbation quotient (PPQ) scores. RESULTS: A sufficient laryngeal airway was achieved in all patients. Six patients (20%) developed postoperative granulation tissue (2 in group 1 and 4 in group 2). There was a statistically significant improvement in FEV1, FEV1/FVC and PEF measurements at the postoperative sixth month compared to preoperative measurements in both of the groups (P < .05). Preoperative median voice quality VAS scores in groups 1 and 2 were 8 (IQR = 1) and 8 (IQR = 3), respectively. Postoperative sixth-month voice quality VAS scores in groups 1 and 2 were 6 (IQR = 1) and 6 (IQR = 0), respectively. Postoperative VAS scores were significantly lower in both groups (P < .05). The postoperative changes in fundamental frequency, NHR, jitter, shimmer, APQ and PPQ were not statistically significant in both of the groups (P > .05). CONCLUSIONS: Laser and diathermy-assisted posterior cordotomy are both minimally invasive, effective techniques with a long-term sufficient laryngeal airway. Despite lower quality of voice VAS scores, objective acoustic outcomes were not significantly lower in both of the groups.

[NEUROSURGICAL INTERVENTIONS FOR INTRACTABLE ONCOLOGICAL PAIN].

INTRODUCTION: Pain is one of the most common symptoms among cancer patients, and particularly in those who suffer from metastatic or terminal disease. There is great importance in delivering good pain management to these patients in order to alleviate their suffering, improve their functional status and their overall quality of life. In most cases, pain management is based on pharmacotherapy with opioids and other medications. However, there are selected patients for whom pharmacotherapy does not achieve acceptable pain relief or is associated with marked side effects. These patients, who suffer from refractory cancer pain, may benefit from neurosurgical procedures selectively intervening in different locations along the pain signaling pathways. This article summarizes several of these neurosurgical procedures: percutaneous cordotomy for unilateral pain, punctuate midline myelotomy for visceral pain and stereotactic cingulotomy for diffuse pain syndromes. This article demonstrates the use of careful patient selection by an interdisciplinary team which is critical for the success of these procedures. The team consists of palliative care specialists, pain specialists and a neurosurgeon. These neurosurgical interventions are presented through representative clinical cases, followed by a discussion of the clinical considerations that guided the choice of the therapeutic approach for each case.

O-Arm-Guided Percutaneous Radiofrequency Cordotomy.

BACKGROUND: Pain is often one of the most debilitating symptoms in patients with advanced oncological disease. Patients with localized pain due to malignancy refractory to medical treatment can benefit from selective percutaneous cordotomy that disconnects the ascending pain fibers in the spinothalamic tract. OBJECTIVES: Over the past year, we have been performing percutaneous radiofrequency cordotomy with the use of the O-Arm intraoperative imaging system that allows both 2D fluoroscopy and 3D reconstructed computerized tomography imaging. We present our experience using this technique, focusing on technical nuances and complications. METHODS: A retrospective analysis was conducted of all patients who underwent percutaneous cordotomy between March 2016 and March 2017. RESULTS: Nineteen patients underwent percutaneous cordotomy procedures. Two patients developed intraoperative delirium and were unable to tolerate the procedure. In 16 out of 17 completed procedures, we achieved excellent immediate pain relief (94%). At 1 month after operation, 15 of the 17 (88%) patients were pain free, and at 3 months 5 out of 5 patients available for follow-up were still free of their original pain. Mirror pain developed in 6 of the 17 patients (35%), but was mild in 4 of these cases and controlled with medications. We experienced 1 serious complication (6%) of ipsilateral hemiparesis. CONCLUSION: Percutaneous cordotomy using the O-Arm is safe and effective in the treatment of intractable oncological pain.

Treatment of medically refractory cancer pain with a combination of intrathecal neuromodulation and neurosurgical ablation: case series and literature review.

OBJECTIVE: Up to 90% of patients with advanced cancer experience intractable pain. For these patients, oral analgesics are the mainstay of therapy, often augmented with intrathecal drug delivery. Neurosurgical ablative procedures have become less commonly used, though their efficacy has been well-established. Unfortunately, little is known about the safety of ablation in the context of previous neuromodulation. Therefore, the aim of this study is to present the results from a case series in which patients were treated successfully with a combination of intrathecal neuromodulation and neurosurgical ablation. DESIGN: Retrospective case series and literature review. SETTING: Three institutions with active cancer pain management programs in the United States. METHODS: All patients who underwent both neuroablative and neuromodulatory procedures for cancer pain were surveyed using the visual analog scale prior to the first procedure, before and after a second procedure, and at long-term follow-up. Based on initial and subsequent presentation, patients underwent intrathecal morphine pump placement, cordotomy, or midline myelotomy. RESULTS: Five patients (2 male, 3 female) with medically intractable pain (initial VAS = 10) were included in the series. Four subjects were initially treated with intrathecal analgesic neuromodulation, and 1 with midline myelotomy. Each patient experienced recurrence of pain (VAS ≥ 9) following the initial procedure, and was therefore treated with another modality (intrathecal, N = 1; midline myelotomy, N = 1; percutaneous radiofrequency cordotomy, N = 3), with significant long-term benefit (VAS 1-7). CONCLUSION: In cancer patients with medically intractable pain, intrathecal neuromodulation and neurosurgical ablation together may allow for more effective control of cancer pain.

Optimization of Radiofrequency Needle Placement in Percutaneous Cordotomy Using Electromyography in the Deeply Sedated Patient.

BACKGROUND AND OBJECTIVES: Cordotomy, the selective disconnection of the nociceptive fibers in the spinothalamic tract, is used to provide pain palliation to oncological patients suffering from intractable cancer-related pain. Cordotomies are commonly performed using a cervical (C1-2) percutaneous approach under imaging guidance and require patients' cooperation to functionally localize the spinothalamic tract. This can be challenging in patients suffering from extreme pain. It has recently been demonstrated that intraoperative neurophysiology monitoring by electromyography may aid in safe lesion positioning. The aim of this study was to evaluate the role of compound muscle action potential (CMAP) in deeply sedated patients undergoing percutaneous cervical cordotomy (PCC). METHODS: A retrospective analysis was conducted of all patients who underwent percutaneous cordotomy while deeply sedated between January 2019 and November 2022 in 2 academic centers. The operative report, neuromonitoring logs, and clinical medical records were evaluated. RESULTS: Eleven patients underwent PCC under deep sedation. In all patients, the final motor assessment prior to ablation was done using the electrophysiological criterion alone. The median threshold for evoking CMAP activity at the lesion site was 0.9 V ranging between 0.5 and 1.5 V (average 1 V ± 0.34 V SD). An immediate, substantial decrease in pain was observed in 9 patients. The median pain scores (Numeric Rating Scale) decreased from 10 preoperatively (range 8-10) to a median 0 (range 0-10) immediately after surgery. None of our patients developed motor deficits. CONCLUSION: CMAP-guided PCC may be feasible in deeply sedated patients without added risk to postoperative motor function. This technique should be considered in a group of patients who are not able to undergo awake PCC.

Surgical/radiological interventions for cancer pain.

Pain is a major morbidity associated with cancer and up to 20% patients require invasive procedures for pain relief. Ablative techniques can be directed towards the spinal cord and brain to palliate pain or modify its perception. Anterolateral cordotomy, myelotomy, DREZotomy and cingulotomy are useful interventions for the management of refractory cancer pain. Advanced imaging modalities, including intraoperative computed tomography (CT) guidance, have increased safety and efficacy of these interventions. In this paper, authors review the recent literature regarding surgical interventions for the management of cancer pain.

Cordotomy for treatment of cancer-related pain: patient selection and intervention timing.

Many neurosurgical interventions for the management of cancer-related pain have been tried, but their role in today's advanced supportive and palliative care is not well described. The authors discuss the current knowledge gaps that prevent successful integration of neurosurgical interventions and patients with cancer-related pain. Two patients underwent percutaneous CT-guided cordotomy for refractory cancer-related pain: one patient had melanoma and the other had ovarian carcinoma. Both patients seemed to have unilateral, somatic, nociceptive cancer-related pain. Cordotomy was effective for only 1 patient. Percutaneous CT-guided cordotomy is a low-risk intervention that can benefit carefully selected patients with cancer-related pain. There is a clear need for prospective controlled studies to evaluate the effectiveness of cordotomy for patients receiving optimal medical treatment. A multidisciplinary study design could help to identify factors correlated with a positive outcome.

Comparison of ventilation and voice outcomes between unilateral laryngeal pacing and unilateral cordotomy for the treatment of bilateral vocal fold paralysis.

BACKGROUND/AIMS: Rehabilitation of the bilaterally paralyzed human larynx remains a complex clinical problem. Conventional treatment generally involves surgical enlargement of the compromised airway, but often with resultant dysphonia and risk of aspiration. In this retrospective study, we compared one such treatment, posterior cordotomy, with unilateral laryngeal pacing: reanimation of vocal fold opening by functional electrical stimulation of the posterior cricoarytenoid muscle. METHODS: Postoperative peak inspiratory flow (PIF) values and overall voice grade ratings were compared between the two surgical groups, and pre- and postoperative PIF were compared within the pacing group. RESULTS: There were 5 patients in the unilateral pacing group and 12 patients in the unilateral cordotomy group. Within the pacing group, postoperative PIF values were significantly improved from preoperative PIF values (p = 0.04) without a significant effect on voice (grade; p = 0.62). Within the pacing group, the mean postoperative PIF value was significantly higher than that in the cordotomy group (p = 0.05). Also, the mean postoperative overall voice grade values in the pacing group were significantly lower (better) than those of the cordotomy group (p = 0.03). CONCLUSION: Unilateral pacing appears to be an effective treatment superior to posterior cordotomy with respect to postoperative ventilation and voice outcome measures.

Two-stage operation for high cervical intramedullary ependymoma in young adult.

We describe a two-stage operation, rarely reported since being introduced in 1911, for treatment of an intramedullary ependymoma extending to the upper cervical cord in a young adult. This classic two-stage strategy combined with modern techniques remains a useful option for selected patients to safely remove intramedullary ependymomas.

Temporal Summation Predicts De Novo Contralateral Pain After Cordotomy in Patients With Refractory Cancer Pain.

BACKGROUND: Percutaneous cervical cordotomy (PCC), which selectively interrupts ascending nociceptive pathways in the spinal cord, can mitigate severe refractory cancer pain. It has an impressive success rate, with most patients emerging pain-free. Aside from the usual complications of neurosurgical procedures, the risks of PCC include development of contralateral pain, which is less understood. OBJECTIVE: To evaluate whether sensory and pain sensitivity, as measured by quantitative sensory testing (QST), are associated with PCC clinical outcomes. METHODS: Fourteen palliative care cancer patients with severe chronic refractory pain limited mainly to one side of the body underwent comprehensive quantitative sensory testing assessment pre-PPC and post-PCC. They were also queried about maximal pain during the 24 h precordotomy (0-10 numerical pain scale). RESULTS: All 14 patients reported reduced pain postcordotomy, with 7 reporting complete resolution. Four patients reported de novo contralateral pain. Reduced sensitivity in sensory and pain thresholds to heat and mechanical stimuli was recorded on the operated side (P = .028). Sensitivity to mechanical pressure increased on the unaffected side (P = .023), whereas other sensory thresholds were unchanged. The presurgical temporal summation values predicted postoperative contralateral pain (r = 0.582, P = .037). CONCLUSION: The development of contralateral pain in patients postcordotomy for cancer pain might be due to central sensitization. Temporal summation could serve as a potential screening tool to identify those who are most likely at risk to develop contralateral pain. Analysis of PCC affords a unique opportunity to investigate how a specific lesion to the nociceptive system affects pain processes.

Percutaneous cervical cordotomy for cancer-related pain: prospective multimodal outcomes evaluation.

BACKGROUND: Percutaneous cervical cordotomy (PCC) offers pain relief to patients with unilateral treatment-refractory cancer-related pain. There is insufficient evidence about any effects of this intervention on patients' quality of life. METHOD: Comprehensive multimodal assessment to determine how PCC affects pain, analgesic intake and quality of life of patients with medically refractory, unilateral cancer-related pain.This study was set in a multidisciplinary, tertiary cancer pain service. Patient outcomes immediately following PCC were prospectively recorded. Patients were also followed up at 4 weeks. RESULTS: Outcome variables collected included: background and breakthrough pain numerical rating scores before PCC, at discharge and 4 weeks postprocedure; oral morphine equivalent opioid dose changes, Patient's Global Impression of Change, Eastern Cooperative oncology group performance status and health related quality of life score, that is, EuroQol-5 dimension-5 level (EQ-5D). CONCLUSIONS: Despite significant improvement in pain and other standard outcomes sustained at 4 weeks, there was little evidence of improvement in EQ-5D scores. In patients with terminal cancer, improved pain levels following cordotomy for cancer-related pain does not appear to translate into improvements in overall quality of life as assessed with the generic EQ-5D measure.

Recovery of hindlimb locomotion after incomplete spinal cord injury in the cat involves spontaneous compensatory changes within the spinal locomotor circuitry.

After incomplete spinal cord injury (SCI), compensatory changes occur throughout the whole neuraxis, including the spinal cord below the lesion, as suggested by previous experiments using a dual SCI paradigm. Indeed, cats submitted to a lateral spinal hemisection at T10-T11 and trained on a treadmill for 3-14 wk re-expressed bilateral hindlimb locomotion as soon as 24 h after spinalization, a process that normally takes 2-3 wk when a complete spinalization is performed without a prior hemisection. In this study, we wanted to ascertain whether similar effects could occur spontaneously without training between the two SCIs and within a short period of 3 wk in 11 cats. One day after the complete spinalization, 9 of the 11 cats were able to re-express hindlimb locomotion either bilaterally (n = 6) or unilaterally on the side of the previous hemisection (n = 3). In these 9 cats, the hindlimb on the side of the previous hemisection (left hindlimb) performed better than the right side in contrast to that observed during the hemispinal period itself. Cats re-expressing the best bilateral hindlimb locomotion after spinalization had the largest initial hemilesion and the most prominent locomotor deficits after this first SCI. These results provide evidence that 1) marked reorganization of the spinal locomotor circuitry can occur without specific locomotor training and within a short period of 3 wk; 2) the spinal cord can reorganize in a more or less symmetrical way; and 3) the ability to walk after spinalization depends on the degree of deficits and adaptation observed in the hemispinal period.