Cryoneurolysis in Patients with Dorsal Neuropathic Pain Secondary to Tumor Invasion.

PURPOSE: To evaluate the safety and efficacy of cryoneurolysis (CNL) in patients with refractory thoracic neuropathic pain related to tumor invasion. MATERIALS AND METHODS: Between January 2013 and May 2017, this single-center and retrospective study reviewed 27 computed tomography-guided CNLs performed on 26 patients for refractory thoracic neuropathic pain related to tumor invasion. Patients with cognitive impairment were excluded. Pain levels were recorded on a visual analog scale (VAS) before the procedure, on days 1, 7, 14, 28 and at each subsequent follow-up appointment. CNL was clinically successful if the postprocedural VAS decreased by 3 points or more. To determine the duration of clinical success, the end of pain relief was defined as either an increased VAS of 2 or more points, the introduction of a new analgesic treatment, a death with controlled pain, or for lost to follow-up patients, the latest follow-up appointment date with controlled pain. RESULTS: Technical success rate was 96.7% and clinical success rate was 100%. Mean preprocedural pain score was 6.4 ± 1.7 and decreased to 2.4 ± 2.4 at day 1; 1.8 ± 1.7 at day 7 (P < .001); 3.3 ± 2.5 at day 14; 3.4 ± 2.6 at day 28 (P < .05). The median duration of pain relief was 45 days (range 14-70). Two minor complications occurred. CONCLUSIONS: Cryoneurolysis is a safe procedure that significantly decreased pain scores in patients with thoracic neuropathic pain related to tumor invasion, with a median duration of clinical success of 45 days.

Percutaneous CT-Guided Cryoablation of the Celiac Plexus: A Retrospective Cohort Comparison with Ethanol.

PURPOSE: To retrospectively analyze and compare the incidence of diarrhea in patients who underwent cryoablation of the celiac plexus for intractable abdominal pain versus ethanol therapy over a 5-year period. MATERIALS AND METHODS: From June 2014 to August 2019, 83 patients were identified who underwent neurolysis of the celiac plexus for management of intractable abdominal pain by using either cryoablation (n = 39 [59% female; age range, 36-79 years old [average, 60 ± 11 years old]) or alcohol (n = 44 [48% female; age range, 29-76 years old [average, 60 ± 12 years old]). Pain scores and reports of procedure-related complications or side effects, with special attention to diarrhea and/or other gastrointestinal symptoms, were collected from follow-up visits at 1 week, 1 month, and 3 months post-intervention and were compared between groups. RESULTS: The mean time of follow-up was 17.7 days. Four patients who underwent cryoablation developed gastrointestinal symptoms consisting of 2 cases of nausea and vomiting and 2 cases of diarrhea (5.1%). Twelve patients who underwent ethanol ablation developed gastrointestinal symptoms, including 1 case of nausea, 3 cases of vomiting, and 9 cases of diarrhea (20.5%). There was a significantly higher incidence of both diarrhea (chi-squared likelihood ratio, P = .03) and overall gastrointestinal symptoms (chi-squared likelihood ratio, P = .04) in the ethanol group than in the cryoablation group. CONCLUSIONS: Cryoablation of the celiac plexus may provide a new treatment option for intractable abdominal pain, and it appears to have a lower incidence of diarrhea and fewer gastrointestinal side effects than ablation using ethanol.

European headache federation consensus on the definition of resistant and refractory migraine : Developed with the endorsement of the European Migraine & Headache Alliance (EMHA).

INTRODUCTION: Despite advances in the management of headache disorders, some patients with migraine do not experience adequate pain relief with acute and preventive treatments. It is the aim of the present document to provide a definition of those migraines which are difficult-to-treat, to create awareness of existence of this group of patients, to help Healthcare Authorities in understanding the implications, and to create a basis to develop a better pathophysiological understanding and to support further therapeutic advances. MAIN BODY: Definitions were established with a consensus process using the Delphi method. Patients with migraine with or without aura or with chronic migraine can be defined as having resistant migraine and refractory migraine according to previous preventative failures. Resistant migraine is defined by having failed at least 3 classes of migraine preventatives and suffer from at least 8 debilitating headache days per month for at least 3 consecutive months without improvement; definition can be based on review of medical charts. Refractory migraine is defined by having failed all of the available preventatives and suffer from at least 8 debilitating headache days per month for at least 6 consecutive months. Drug failure may include lack of efficacy or lack of tolerability. Debilitating headache is defined as headache causing serious impairment to conduct activities of daily living despite the use of pain-relief drugs with established efficacy at the recommended dose and taken early during the attack; failure of at least two different triptans is required. CONCLUSIONS: We hope, that the updated EHF definition will be able to solve the conflicts that have limited the use of definitions which have been put forward in the past. Only with a widely accepted definition, progresses in difficult-to-treat migraine can be achieved. This new definition has also the aim to increase the understanding of the impact of the migraine as a disease with all of its social, legal and healthcare implications. It is the hope of the EHF Expert Consensus Group that the proposed criteria will stimulate further clinical, scientific and social attention to patients who suffer from migraine which is difficult-to-treat.

A Delphi consensus statement of the Neuropathic Pain Special Interest Group of the Italian Neurological Society on pharmacoresistant neuropathic pain.

To improve patient care and help clinical research, the Neuropathic Pain Special Interest Group of the Italian Neurological Society appointed a task force to elaborate a consensus statement on pharmacoresistant neuropathic pain. The task force included 19 experts in neuropathic pain. These experts participated in a Delphi survey consisting of three consecutive rounds of questions and a face-to-face meeting, designed to achieve a consensus definition of pharmacoresistant neuropathic pain. In the three rounds of questions, the participants identified and described the main distinguishing features of pharmacoresistance. In the face-to-face meeting the participants discussed the clinical features determining pharmacoresistance. They finally agreed that neuropathic pain is pharmacoresistant when "the patient does not reach the 50% reduction of pain or an improvement of at least 2 points in the Patient Global Impression of Change, having used all drug classes indicated as first, second, or third line in the most recent and widely agreed international guidelines, for at least 1 month after titration to the highest tolerable dose." Our consensus statement might be useful for identifying eligible patients for invasive treatments, and selecting patients in pharmacological trials, thus improving patient care and helping clinical research.

Measuring sensory and pain thresholds by Semmes-Weinstein monofilaments in patients with leg ulcers: a pilot study.

OBJECTIVE: Pain is a common and disabling symptom in patients with leg ulcers. Clinical quantification of pain mostly depends on subjective pain reports, which do not reveal underlying mechanisms. The aim of this pilot study is to identify mechanisms underlying the pain in patients with leg ulcers by documenting alterations in pain processing using quantitative sensory testing. METHODS: In nine ulcer patients the mechanical sensory thresholds and the mechanical pain thresholds were determined by Semmes-Weinstein monofilaments (SWM) at three different sites: on the contralateral (unaffected) leg, on the skin of the affected leg 10cm from the ulcer margin, and on the affected leg, close (1-2cm) to the ulcer margin. Besides the mechanical sensory thresholds and mechanical pain thresholds, pain at the site of the ulcer, using an 11-point numeric rating scale (NRS), was documented. RESULTS: Mechanical sensory thresholds were increased in all subjects. Almost half (44%) of patients consistently showed allodynia at the unaffected site. The lowering of mechanical pain thresholds correlated with higher scores on the NRS. CONCLUSION: All patients showed diminished touch and/or protective sensation, which might have contributed to ulcer development via (partial) loss of protective function. The allodynia at the unaffected site suggests the presence of central sensitisation of pain processing.

Determinants for Meaningful Clinical Improvement of Pain and Health-Related Quality of Life After Spinal Cord Stimulation for Chronic Intractable Pain.

OBJECTIVES: Previous studies demonstrated significant improvement in mean pain scores and quality of life (QOL) scales in patients with chronic pain who underwent spinal cord stimulation (SCS). However, the number of individuals who experience relevant improvements in QOL, termed the meaningful clinical improvement (MCI), is not known. The present study investigated changes in pain measurements based on MCI after SCS. MATERIALS AND METHODS: Thirty-four patients with chronic intractable pain completed scales of pain (visual analogue scale [VAS]), QOL (SF-36), and psychological dimensions during a 22-month follow-up period (mean). Patient-centered MCI of the VAS and SF-36 domain scores were determined based on the MacNab criteria of surgical global effectiveness. Independent presurgical predictors for MCI in the VAS and SF-36 domains were analyzed using multiple binary logistic regression. RESULTS: There was significant improvement of pain and QOL after the SCS (p < 0.00001). Twenty-three patients (67.6%) reached an MCI of pain, and 16 (47.7%)-23 (67.7%) reported an MCI of QOL. Predictors of MCI included ≥80% paresthesia coverage of the painful area, lower levels of anxiety and catastrophizing symptoms, shorter pain duration, female gender and no use of opioids before surgery. MCI of pain and QOL was observed in 50%-70% of patients with chronic pain after SCS. CONCLUSIONS: The identification of determinants for MCI is a challenge to improve the accuracy of prognostic models in SCS for patients with chronic pain. Our results, if confirmed in other populations with a larger sample size, have implications for patients with chronic pain who are candidates for SCS treatment.

Comparison of the Effects of Intermittent Boluses to Simple Continuous Infusion on Patients' Global Perceived Effect in Intrathecal Therapy for Pain: A Randomized Double-Blind Crossover Study.

Objective: Intrathecal drug delivery (ITDD) is commonly used for intractable pain management. A paucity of good-quality studies in chronic noncancer patients and concerns over increased dosages have focused interest on different modes of administration. The aim of this international multicenter randomized double-blind crossover trial was to compare the efficacy of the same daily dose of drugs administered by intermittent boluses vs simple continuous infusion. Methods: Eligible patients implanted with a programmable ITDD device were randomized to receive two weeks of either intermittent boluses or a simple continuous flow in period 1, followed by a crossover to the alternative mode of administration. The primary outcome measure was the Patients' Global Impression of Change (PGIC) scale. Results: The mean proportion of positive responders (at least "minimally improved") was 38.4% in the continuous condition vs 37.3% in the bolus (difference in proportions = 1.1%, 95% confidence interval [CI] = -21.8-24.0%, P = 0.93). The mean PGIC in the continuous condition was 3.8 vs 3.9 in the bolus (mean difference = -0.1, -0.6-0.4, P = 0.72). Exploratory analyses revealed a tendency for the mean proportion of positive responders to be higher at low vs high flow rates for both bolus and continuous administrations. Two patients were withdrawn from the study due to adverse events during the bolus phase, both with symptoms of increased pain, and one patient with additional symptoms of numbness and urinary retention. Conclusion: The mean PGIC and proportion of positive responders was not substantially different after intermittent bolus vs continuous administration.

Short-term outcomes of patients being treated for chronic intractable pain at a liaison clinic and exacerbating factors of prolonged pain after treatment.

BACKGROUND: Although a multidisciplinary approach is often recommended to treat intractable pain, this approach does not completely prevent uncontrolled pain in some patients. The aim of this retrospective study was to investigate the exacerbating factors of prolonged, intractable pain among patients being treated at a pain liaison clinic. METHODS: The participants of this study were 94 outpatients (32 men, 62 women) with chronic intractable pain who visited our hospital between April 2013 and February 2015. Demographic and clinical information was obtained from all patients at baseline. Experts in various fields, including anesthesia, orthopedic surgery, psychiatry, physical therapy, and nursing, were involved in the treatment procedures. All patients were assessed before and after a 6-month treatment period using the following measures: the Numeric Rating Scale (NRS); the Pain Catastrophizing Scale (PCS); the Hospital Anxiety and Depression Scale (HADS); the Pain Disability Assessment Scale (PDAS); and the Oswestry Disability Index (ODI). All participants were then divided into two groups based on their self-reported pain after treatment: a pain relief group (n = 70) and a prolonged pain group (n = 24). The exacerbating factors of prolonged pain after treatment in the pain liaison outpatient clinic were analyzed using univariate and multiple logistic regression analysis. RESULTS: A significant improvement in NRS scores was observed after the 6-month follow-up period. After treatment, 24 (25.5%) of the 94 patients reported having prolonged pain. Significant improvements were seen in the PCS, PDAS, and ODI scores in the pain relief group, and in the HADS depression scores in the prolonged pain group. On univariate and multiple regression analysis, HADS depression scores were identified as a factor related to prolonged pain after treatment. CONCLUSIONS: The results of the present study suggest that severe depression at the initial visit to the liaison outpatient clinic was an exacerbating factor for prolonged pain after treatment.

Atypical Presentation of Fibrolipomatous Hamartoma of Superficial Peroneal Nerve.

Fibrolipomatous hamartoma is a rare presentation in the foot. An accurate diagnosis is key, with magnetic resonance imaging findings considered definitive. The management is dependent on the symptoms. We present an atypical presentation of fibrolipomatous hamartoma of the superficial peroneal nerve and discuss the current published data.

Patient quality of life and pain improve after autologous islet transplantation (AIT) for treatment of chronic pancreatitis: 53 patient series at the University of Arizona.

BACKGROUND/OBJECTIVES: Pancreatectomy with autologous islet transplantation has slowly been proving to be an effective way of treating chronic pancreatitis while lessening the effects of the concomitant surgical diabetes of pancreatectomy alone. Assessing patient quality of life and pain after the procedure is particularly important as intractable pain is the main complaint for which patients undergo total pancreatectomy. METHODS: We used the Rand SF-36 and McGill pain questionnaires, and Visual Analogue Scale to assess patients preoperatively for quality of life and pain resulting from life with chronic pancreatitis. After undergoing total pancreatectomy with autologous islet transplantation (TPAIT), patients were followed with surveys administered at 1 month, 6 months, and 1 year to evaluate changes in their quality of life and pain experienced. RESULTS: Significant improvement was reported in all components of every questionnaire within a year after surgery. Furthermore, patient reported mean scores on quality of life were found to fall within the range of the general population. CONCLUSIONS: From our experience with 53 patients at the University of Arizona, after pancreatectomy with autologous islet transplantation patients reported a higher quality of life when compared to preoperative values, as well as reduced levels of pain.

Long-term results of motor cortex stimulation in the treatment of chronic, intractable neuropathic pain.

BACKGROUND/OBJECTIVES: Although motor cortex stimulation (MCS) has been used for more than 20 years in the treatment of chronic neuropathic pain, there is still a debate about the efficacy of MCS. METHODS: To investigate the long-term results and the factors associated with the long-term success of chronic MCS, 21 patients who underwent MCS trial were classified as having central poststroke pain, central pain after spinal cord injury (SCI) and peripheral neuropathic pain, and we investigated the clinical factors associated with long-term success and degree of pain relief. RESULTS: Of the 21 patients, 16 (76.2%) had a successful trial and underwent chronic MCS. In the long-term follow-up (53 ± 39 months), only the diagnosis (central poststroke pain and peripheral neuropathic pain) was associated with long-term success defined as >30% pain relief compared with baseline (p < 0.05, χ(2) test). The difference in pain relief was not significant in patients having SCI pain (p > 0.05, 1-way ANOVA). The other variables did not show any significant influence in the long-term success and degree of pain relief (p > 0.05, 1-way ANOVA). CONCLUSIONS: MCS was more effective in the treatment of chronic neuropathic pain of central poststroke pain and peripheral neuropathic pain types than in the treatment of SCI pain in the long-term follow-up.

[Are artificial disorders common in palliative care? A Case report]. / Sind artifizielle Störungen im palliativen Kontext häufig? Ein Fallbericht.

The main task of palliative care specialists is to focus on symptom control such as pain, nausea or fatigue. Thorough anamnesis, physical examination, laboratory examination, and differential diagnosis can ensure appropriate treatment. In an increasing number of cases psychiatric conditions like depression or anxiety increase also occur so palliative care physicians need to be more prepared to handle them. The question of this case report is, how a palliative care specialist can distinguish between a malignant disease or neurological disease progression and a presentation primarily psychiatric in etiology, as is the case in factitious disorders. We are also interested in the incidence rate of such factitious disorders. Our case study demonstrates that it is rare but not impossible that a doctor will encounter factitious symptoms in the palliative setting. This suggest being aware of evidence of psychiatric origins even in discharge letters and referrals that indicate palliative care needs, to ensure that palliative care really is the best treatment option for the patient. We do believe such cases to be rare in a palliative setting, however.

The importance of assessing pain in adults.

Pain affects patients physically and emotionally, so successfully managing the pain they experience is a key component of their recovery. This third article in a series on pain looks at why it is important to assess pain in adults and how this can best be done. The causes and symptoms of chronic and acute pain are detailed, along with the different assessment tools that can be used and for which patients they are suitable.

Percutaneous vertebroplasty performed with an 18-gauge needle for treatment of metastatic severe compression fracture of the cervical vertebral body.

Percutaneous vertebroplasty (PVP) is considered technically difficult in patients with severe vertebral body compression, especially in the cervical spine. In this study, PVP was successfully performed with the use of an 18-gauge angiographic needle in four patients with severe cervical compression fractures from metastatic disease. There were no complications, and relief of pain was immediate in all patients. This technique may be an alternative treatment for intractable pain secondary to severe cervical compression fractures.

Usefulness of screening tools in the evaluation of long-term effectiveness of DREZ lesioning in the treatment of neuropathic pain after brachial plexus injury.

BACKGROUND: Despite high success rate of DREZ lesioning in the treatment of intractable central pain, there is still a significant incidence of patients without satisfactory post-operative effect. The aim of the study was to evaluate the long-term effect of DREZ lesioning using both a subjective assessment using a visual analog scale (VAS) to quantify residual pain and an assessment using the screening tool (painDETECT Questionnaire, PD-Q). METHODS: DREZ lesioning was performed in 52 patients from a total 441 cases with brachial plexus injury (11.8%) during a 17-year period (1995-2011). The effect of surgery was retrospectively assessed in 48 patients. RESULTS: A decrease in pre-operative pain by more than 75% (Group I) was achieved in 70.8% of patients and another 20.8% reported significant improvement (Group II). The surgery was unsucessful in 8.4% (Group III). We found a significant correlation between 'improvement' groups from both methods of assessments. Patients from Group I usually complained of residual nociceptive pain according to PD-Q, patients from Group II typically had pain of unclear origin, and all cases those in Group III suffered from neuropathic pain, Cramer's V = .66, P < .001. Overall, 66.7% of patients had resolved neuropathic pain, 20.8% patients had more serious complaints and may also suffer from residual neuropathic pain, while 12.5% had unresolved neuropathic pain. CONCLUSION: DREZ lesioning is a safe and effective method with success rates of about 90%. PD-Q scores correspond to subjective satisfaction with the surgery and it seems to be a suitable screening tool for finding patients with residual neuropathic pain after surgery.

Refractory Chronic Pain Screening Tool (RCPST): a feasibility study to assess practicality and validity of identifying potential neurostimulation candidates.

OBJECTIVE: An international panel of pain specialists (anesthesiology, neurology, neurosurgery, and psychology) and research methodologists developed a screening tool to identify patients who may be suitable for spinal cord stimulation (SCS)--the Refractory Chronic Pain Screening Tool (RCPST) prototype. We describe a feasibility study to explore practicality and validity of this prototype. DESIGN: Consecutive outpatients were screened in two centers (United Kingdom and United States). Sixty chronic pain adults without satisfactory pain relief despite treatment were assessed using RCPST (by pain specialist without expertise in neurostimulation) and then evaluated by two pain specialists experienced in SCS implantation and management to determine whether the patient should be referred for SCS. To maintain blinding, the participating physicians did not inform each other or the patient of assessment outcome. Sensitivity and specificity of the RCPST prototype were calculated using implanters' judgment as "gold standard." RESULTS: The average age of patients was 47.7 years; 53% were female. Fifty-seven patients completed the study (one withdrew consent, two lost to follow-up). The pain specialists agreed the prototype was easy to use and took <10 minutes to complete. Implanter agreement was moderate (Kappa: 0.63, 95% confidence interval: 0.35-0.91). The prototype had low sensitivity (40%, 19-61%) and moderate specificity (78%, 65-92%). Using the same questionnaire with a modified decision algorithm, new prototypes were generated with range of high sensitivity (80-100%) and specificity (89-97%) values. CONCLUSIONS: The RCPST aims to identify patients that should be referred for consideration for neurostimulation. The final implant decision requires appropriate neurological diagnostic workup, psychological assessment, and trial stimulation. RCPST was considered practical for routine clinical practice and contained appropriate questions. Sensitivity needs to be improved. A future study should select and validate the ideal RCPST prototype.

[Diagnostic and therapeutic devices for patients with chronic intractable pain: preface and comments].

New diagnostic and therapeutic devices for patients with chronic intractable pain are used in Japan. The following articles describe topics of new diagnostic and therapeutic devices for patients with chronic intractable pain including thermography, functional MRI, device for the quantitative analysis of perception and pain sensation, epiduroscopy, device for phototherapy, Racz catheter and device for spinal cord stimulation (SCS).

Buprenorphine: Opioid Agonist-Antagonist for Refractory Pain of Sickle Cell Disease Patients During Hematopoietic Stem Cell Transplant, Uncontrolled By Full-Agonist Opioids.

BACKGROUND: Bone marrow transplant (BMT) offers potential cure for cancer and a spectrum of otherwise incur- able diseases. The BMT process can cause multi-systemic pain in patients with sickle cell disease (SCD) refractory to high-dose opioid analgesics during BMT because of their pre-existing opioid-tolerance. Because of frequent pain resulting in hyperalgesia and chronic opioid use, SCD patients undergoing BMT often experience excruciating pain uncontrolled by exceedingly high-dose opioids with severe and intolerable adverse effects. PURPOSE/HYPOTHESIS: There is a small but growing body of literature about the successful buprenorphine effect for SCD's chronic pain management that had failed sufficient pain relief by the traditional full-agonist opioids in the outpatient setting. However, the buprenorphine use for acute inpatient pain management has not been previously researched. Pilot prospective clinical trial with buprenorphine-based pain management for acute BMT-related pain was initiated for SCD patients' pain uncontrolled by full-agonist opioids. Procedures/data/observations: Buprenorphine was started as scheduled and as-needed analgesics, supplemented by full-agonist opioids upon consultation for uncontrolled BMT-related pain of SCD patients. Patients' 24-hour opioid requirement by morphine equivalent daily doses (MEDD) were assessed at 3 time points: 1)immediately before pain escalation; 2)consultation; 3)discharge. MEDDs were compared to those of patients treated with full-agonist opioids only. Cases treated by full-agonist opioids (morphine/hydromorphone/fentanyl/methadone/oxycodone) had MEDD escalation by 1230-16300% by discharge compared to immediately before BMT-related pain escalation. Buprenorphine-supported cases had significantly smaller MEDD increase by 220-317%. CONCLUSIONS/APPLICATIONS: Our case series suggests superior pain control by adding Buprenorphine prior to opioid dose escalation during BMT for SCD. Buprenorphine may provide the advantageous effect for other patients with complex pain background and experiencing difficult pain management during BMT due to pre-existing hyperalgesia and high opioid-tolerance. The evidence for buprenorphine's analgesic effect is moderate but growing, and more randomized controlled trials comparing the buprenorphine and other standard opioids are needed.

Cluster headache: potential options for medically refractory patients (when all else fails).

The most evidence exists for mixed anesthetic/steroid occipital nerve blocks (which are also useful in non-refractory patients), deep brain stimulation, sphenopalatine ganglion (SPG) blocks, SPG radiofrequency ablation, and SPG stimulation with the Autonomic Technologies, Inc (ATI) SPG Neurostimulator, the latter approved in the European Union and reimbursed in several countries.