Adult brainstem glioma presenting with isolated persistent hemifacial spasm or facial nerve palsy.

OBJECT: Adult brainstem gliomas are a rare group of heterogeneous brain tumors. Classical clinical presentation includes progressive impairment of cranial nerves associated with long tract signs. The prognosis and response to treatment are poor; nevertheless, some patients do have a long survival. The objective of this study was to describe a series of patients with an isolated persistent hemifacial spasm and/or facial nerve palsy as the presenting symptom of a brainstem glioma. METHODS: Fourteen patients from 3 French hospitals (Paris, Caen, Lille) were included. Clinical and radiological features and overall survival were retrospectively analyzed. A review of the literature of similar cases was performed. RESULTS: Mean age at diagnosis was 35 years (range 19-57 years). Mean duration of facial nerve involvement before diagnosis was 17 months (range 1-48 months). Tumors were characterized on MRI by a lateralized location in the pons, a T1-weighted hyposignal, a T2-weighted hypersignal and no contrast enhancement after Gadolinium injection except for 2 cases. Biopsies were performed in 10 cases and showed 8 low-grade and 2 high-grade gliomas. All the patients were initially treated with radiotherapy and 6 patients with chemotherapy after progression. Eleven patients died from tumor progression. Median survival time was 90 months. CONCLUSIONS: Adult brainstem gliomas revealed by a progressive isolated involvement of the facial nerve seem to have particular clinico-radiological features of slow progressive tumors and may be associated with long patient survival.

Multimodal management of ruptured cerebral micro-arteriovenous malformations: A retrospective series of 19 cases and a review of the literature.

BACKGROUND: Micro-arteriovenous malformations (micro-AVMs) are defined as AVMs just visible on angiography with a nidus size between 0.5 and 1cm. Their principal manifestation is intracranial hemorrhage and their diagnosis and therapeutic management are still unclear. METHODS: The aim of our work was to show the clinical presentation, treatment and outcome of ruptured cerebral micro-AVMs in a retrospective cohort study of 19 patients and a systematic review of the literature. RESULTS: We obtained a total of 20 micro-AVMs in 19 patients. The mean age was 47.3 years. Clinical presentation was acute bleeding. The mean volume of hematoma was 12.9 mm3 (0 - 60.4), with topographic distribution as follows: 64% cortical with supratentorial bleeding, 26% deep, and 10% in the posterior fossa. Among the 20 micro-AVMs of the series, 11 (55%) had endovascular management, 6 (30%) had surgical treatment and 3 (15%) had GK radiosurgery alone. All of our patients have been cured at the end of the follow up without re-permeabilization. In our series, clinical outcome showed good recovery with a mean score of 4.6 on Glasgow Outcome Scale (GOS). In the literature, 88% of patients had a GOS of 4 or 5. DISCUSSION: Intracerebral hematoma (ICH) was the main clinical manifestation. In the case of negative initial angiographic assessment, patients must have supraselective angiographic exploration. In the case of conservative treatment of hematoma, endovascular obliteration and microsurgical exclusion seems to be reasonable therapeutic options, according to our observations.

[Isolated intracranial relapse in previously treated Hodgkin's disease]. / Rechute intracérébrale isolée dans la maladie de Hodgkin.

UNLABELLED: Isolated brain relapse is uncommon in Hodgkin's lymphoma and often linked with advanced or refractory disease. CASE REPORTS: We report two patients with stage IV Hodgkin's disease, previously treated with chemotherapy, who later developed neurological symptoms. Brain MRI demonstrated two different types of lesions. Histological findings were consistent with intracranial location of Hodgkin lymphoma. Both of the patients presented only with isolated CNS relapse of the lymphoma. CONCLUSION: The two cases demonstrated the MRI appearance of intracranial involvement can be varied and mimic other disease processes in patients with a previous history of Hodgkin's lymphoma. Thus, a biopsy is necessary for diagnosis and correct treatment.

Post-movement beta synchronization in subjects presenting with sensory deafferentation.

OBJECTIVE: We studied the time course and location of post-movement beta synchronization (PMBS) in patients presenting with sensory deafferentation, in order to assess the hypothetical relationship between the PMBS and the cortical processing of movement-related somatosensory afferent inputs. METHODS: We used the event-related synchronization (ERS) method. EEG activity was recorded (via a 128-electrode system) during brisk, unilateral right and left index finger extension by 10 patients presenting with neuropathic pain related to sensory deafferentation. Intra- and post-movement changes in beta source power were calculated relative to pre-movement baseline activity. We compared the PMBS results for the painful and non-painful body sides. Furthermore, PMBS patterns in patients were compared with those in nine healthy volunteers. RESULTS: PMBS pattern related to the painful side had a spatial distribution, with an ipsilateral preponderance, significantly more restricted than PMBS pattern on the non-painful side and in the control group. There were no significant differences between patient PMBS patterns on the non-painful side and those in the control group. CONCLUSIONS: Sensory deafferentation disrupts normal PMBS patterns. SIGNIFICANCE: This work provides additional arguments to the hypothesis supporting that the PMBS is influenced by movement-related somatosensory input processing.

Comparison of botulinum toxin injection and neurotomy in patients with distal lower limb spasticity.

BACKGROUND AND PURPOSE: We compared the efficacy of botulinum toxin injection (BTI) and tibial nerve neurotomy (TNN) in an open-label study of 34 post-stroke hemiplegic patients with distal lower limb deformation. METHODS: The dose of BT was 300 U (Botox). TNN was performed with a 6-12 month delay on the motor branches of the tibial nerve. Muscles to be treated were selected according to the distal deformity (equinus, varus and clawing toes). Patients were assessed following each treatment for spasticity, motor control, range of movements, balance, gait and the Rivermead Motor Assessment. RESULTS: TNN (M3, M6 and Y1) resulted in a more significant effect than BTI (D15, M2 and M5) on most of the measures: ankle plantar flexor spasticity, range of movement in dorsiflexion and eversion, foot position in upright situation, Functional Ambulation Categories (barefoot), RMA, gait velocity (comfortable condition), subjective benefit and use of walking aids. Patients treated for tibialis posterior or flexor digitorum longus spasticity often complained of subjective sensory disorders at the plantar sole over a period of 4-6 weeks. CONCLUSION: In conclusion, TNN is more effective than BTI on most of the functional parameters. The interest of BTI lies in the preliminary testing of the efficacy of a technique for reducing spasticity on lower limb function.

[Neurostimulation procedures in refractory pain]. / Techniques de neurostimulation et douleurs réfractaires.

In the context of chronic pain, the technics of neuromodulation have a significative place especially when they are neuropathic with a precise selection of the indications according to the neurophysiological, anatomical and clinical data. The choice is essentially based upon the severity and the site of pain. They are totally conservative, adaptable and reversible but it is necessary to organize a very rigorous clinical and technical follow-up according to a multidisciplinary approach.

TSH-secreting adenoma improved with cabergoline.

TSH-secreting adenomas are rare tumors, representing only 0.5 to 2.5% of pituitary adenomas. Their main clinical characteristics include signs of thyrotoxicosis, diffuse goiter and a compressive syndrome. Biologically, free T4 and T3 serum levels are elevated, contrasting with inadequate serum TSH levels and increased alpha chains. Magnetic resonance (MR) imaging shows a pituitary tumor, the main differential diagnosis being resistance to thyroid hormones. Treatment is based on surgery, possibly associated with somatostatin analogs and radiotherapy. Though the long-term evolution of this rare pathology seems to have improved, some clinical situations are still a challenge to treat. We report one such case that was resistant to both stereotactic radiotherapy and somatostatin analogs, but surprisingly improved with cabergoline. We suggest that cabergoline should be considered as an alternative treatment in cases of pituitary adenomas that resist traditional treatments.

Intracranial dissemination of primary spinal cord anaplastic oligodendroglioma.

We report the first case of a 22-year-old man, with a previously neurosurgically treated intramedullary anaplastic oligodendroglioma (World Health Organization grade III), who developed 19 months later two histologically proven intracranial metastases. We support a hypothesis whereby the anaplastic parts of tumors have spread along the spinal cord and brainstem via the cerebrospinal fluid pathways, a process that could be promoted by surgical manipulation, although the relative contribution of the two factors remains speculative.

Prognosis factors of survival time in patients with glioblastoma multiforme: a multivariate analysis of 340 patients.

BACKGROUND: The prognosis of glioblastoma multiforme remains poor despite recent therapeutic advances. Several clinical and therapeutic factors as well as tumour characteristics have been reported as significant to survival. A more efficient determination of the prognostic factors is required to optimize individual therapeutic management. The aim of our study was to evaluate by univariate then multivariate analysis the factors that influence prognosis and particularly survival. METHODS: Data of 340 patients with newly-diagnosed GBM were retrospectively analyzed. Univariate analysis of prognosis factors of survival time was performed. Factors that seemed determinant were evaluated by Kaplan-Meier survival curves. Finally, the significant factors found in univariate analysis were tested in multivariate analysis using the COX regression method. FINDINGS: Using multivariate analysis, the following factors were found to influence survival: radiotherapy was the predominant factor followed by radical surgery, tumour location, age and chemotherapy. Patients treated with temozolomide had a markedly better survival rate than patients treated with other chemotherapies (Log-rank test P < 0.005). The values of GBM type (de novo or secondary), as well as repeated surgery and partial surgery (vs. simple biopsy) were suggested by univariate analysis but not confirmed by the COX regression method. After radical surgery, progression-free survival was correlated to overall survival (r = 0.87, P < 10e-5). CONCLUSIONS; The influence of radiotherapy on survival was greater than the influence of age, an argument supporting the proposition of radiotherapy for patients until at least age 70. In the case of recurrence, the correlation between overall survival and progression-free survival is an important factor when considering the therapeutic options. Initial radical surgery and repeated procedures dramatically influence survival. The benefit of partial surgery remains difficult to evaluate. Partial surgery could be used to decrease intracranial pressure and to minimize residual tumours in order to enable treatment by chemotherapy and radiotherapy. The value of temozolomide treatment was confirmed.

Predominance of the contralateral movement-related activity in the subthalamo-cortical loop.

OBJECTIVE: Abnormal low- and high-frequency oscillatory activities have been linked to abnormal movement control in Parkinson's disease. We aimed to study how low- and high-frequency oscillatory activities are modulated by movement in the contralateral and ipsilateral subcorticocortical loops. METHODS: We studied mu, beta and gamma rhythm event-related desynchronisation (ERD) and synchronisation (ERS) recorded from electrode contacts in the subthalamic nucleus (STN) areas and over the primary sensorimotor (PSM) cortex. RESULTS: Mu and beta ERD/ERS patterns were very similar when comparing PSM cortex and STN areas and very different when comparing contralateral and ipsilateral structures. Beta rhythm ERS was more predominant over contralateral structures than over ipsilateral ones. Gamma rhythm ERS was only recorded from the contralateral STN area (particularly following administration of L-Dopa). For all patients, the best bipolar derivations - as defined by the earliest mu and beta ERD and the strongest beta and gamma ERS - always included the STN electrode contacts that produced the best clinical results. CONCLUSIONS: Movement-related activity is involved in the movement preparation in the contralateral subthalamo-cortical loop and in the movement execution in the bilateral subthalamo-cortical loops. SIGNIFICANCE: Contralateral beta rhythm ERD seemed to be related to bradykinesia of the limb performing the movement.

Stimulation of the subthalamic nucleus in Parkinson's disease: cognitive and affective changes are not linked to the motor outcome.

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN0 DBS) is a widely performed surgical treatment in PD. However, the relationship between motor results and cognitive/behavioural modifications is unclear. OBJECTIVE: This study investigated the correlation patterns of the motor, cognitive and behavioural consequences of STN DBS with respect to positioning of the active contact. METHODS: Fifty-eight consecutive PD patients having undergone STN DBS were assessed pre-operatively and 12 months after surgery. RESULTS: Motor, cognitive and behavioural results were neither correlated to each other nor linked to the position of the active contact. Three patients with a history of pre-operative, dopaminergic psychosis or post-surgical confusion became demented. Age and a distant history of depression were associated with the occurrence of post-surgical depression. CONCLUSION: Correct screening of patients for STN DBS remains an important issue, since the current implantation procedure is not able to take account of potential functional heterogeneity within the target.

Kinetics and importance of the dimerization step in the folding pathway of the beta 2 subunit of Escherichia coli tryptophan synthase.

During its folding, the polypeptide chain of the beta 2 subunit of Escherichia coli tryptophan synthase (L-serine hydrolyase (adding indole) EC 4.2.1.20) undergoes dimerization. To decide whether this dimerization precedes or follows the formation of the native, functional, tertiary structure of the polypeptide chain, the kinetics of renaturation of beta 2 are studied by monitoring both the regain of native conformation and the dimerization. Dimer formation is followed by the increase of the fluorescence polarization, or by energy transfer between a fluorescence donor and a fluorescence acceptor, which occur upon association of adequately labelled beta chains. Renaturation is followed by the regain of functional properties of beta 2, i.e. its ability to bind pyridoxal-5'-phosphate or to form a fluorescent ternary complex with this coenzyme and L-serine. It is shown that for beta 2 the dimerization obeys first-order kinetics, presumably because it occurs rapidly after a rate-limiting isomerization of the monomer. The dimerization is followed by another isomerization, taking place within the dimer, which leads to the formation of the pyridoxal-5'-phosphate binding site. Still another, slow, isomerization reaction involving the F1 (N-terminal) domain completes the renaturation. With a modified form of beta 2 (trypsin-nicked beta 2) where this isomerization of F1 can be made to occur before the dimerization, the dimer is also shown to appear before the functional properties. It is concluded that a non-native dimer indeed exists as an obligatory intermediate on the folding pathway of nicked beta 2 and of beta 2, and that interdomain interactions are needed to force the polypeptide chains into their native conformations.

[Pathophysiological mechanisms implicated by high-frequency stimulation in Parkinson's disease: the restoration of high and low frequency oscillatory systems]. / Mécanismes physiopathologiques de la stimulation à haute fréquence dans la maladie de Parkinson: restauration des systèmes oscillatoires de haute et basse fréquences.

INTRODUCTION: Increased neuronal activity in the internal pallidum (GPi) and the subthalamic nucleus (STN) has been clearly demonstrated in Parkinsonian models, and the two structures have thus been selected as therapeutic targets for functional neurosurgery. High-frequency electrical stimulation of the GPi or the STN improves the parkinsonian symptoms but also dyskinesias directly by GPi stimulation or indirectly by reduction of L-Dopa associated with STN stimulation. According to Alexander's model of the organisation of the basal ganglia, electrical stimulation of GPi or STN should have led to uncontrolled hyperkinesia. This apparent paradox could be explained on one hand by the involvement of different anatomo-functional areas within these structures and on the other by spatial and temporal changes in neuronal discharge patterns in the basal ganglia which in turn produce variations in synchronisation. RESULTS: Event-related (de)synchronisation (ERD) has enabled us to study variations in subcortico-cortical oscillatory activity: it has been shown that high-frequency electrical stimulation of the GPi/STN increases desynchronisation of low frequency rhythms (mu and beta,<30 Hz) during movement preparation and execution and augments post-movement synchronisation. Stimulation also decreases the abnormal frontocentral spreading of desynchronisation during movement preparation. CONCLUSIONS: In accordance with previous coherence analyses, electrical stimulation of STN is likely to restore the activity of high-frequency and low-frequency systems, as evidenced by a decrease in the hypersynchronisation of low-frequency rhythms at rest and restoral of a high-frequency rhythm during movement. Stimulation may improve spatial selectivity by activating the selected programs in conjunction with the primary sensorimotor cortex, whilst inhibiting competitive programs represented by abnormal spreading outside the primary sensorimotor cortex.

Anatomy, physiology and neurobiology of the nociception: a focus on low back pain (part A).

INTRODUCTION: The treatment of Failed Back Surgery Syndrome (FBSS) remains a challenge for pain medicine due to the complexity in the interactions between [1] a residual mechanical pain after surgery and, [2] a progressive transition into chronic pain involving central nervous system plasticity and molecular reorganization. The aim of this paper is to provide a fundamental overview of the pain pathway supporting the nociceptive component of the back pain. METHODS: Literature searches included an exhaustive review of 643 references and 74 book chapters updated by searching the major electronic databases from 1930 to August 2013. RESULTS: Pain input is gathered by the peripheral fibre from the innervated tissue's environment and relayed by two contiguous central axons to the brain, via the spinal cord. At this level, it is possible to characterize physical pain and emotional pain. These are supported by two different pathways, encoding two dimensions of pain perception: In Neo-spino-thalamic pathway, the wide dynamic range neuron system is able to provide the information needed for mapping the "sensory-discriminative" dimension of pain. The second projection system (Paleo-spino-thalamic pathway) also involves the ventromedial thalamus but projects to the amygdala, the insula and the anterior cingulate cortex. These areas are associated with emotionality and affect. CONCLUSION: The mechanical component of FBSS cannot be understood unless the functioning of the pain system is known. But ultimately, the highly variable nature of back pain expression among individuals would require a careful pathophysiological dissection of the potential generators of back pain to guide pain management strategies.

Pathophysiological characterisation of back pain generators in failed back surgery syndrome (part B).

INTRODUCTION: Low back surgery, including as many type of spine procedures as the multitude of failed back surgery syndrome (FBSS) etiologies, is not always the answer for patients with chronic low back pain. Paradoxically, although a patient is considered to present FBSS because he has already undergone spinal surgery, any new symptom in the back or deterioration of back pain must not be immediately attributed to FBSS, but could be related to another cause independently of the initial mechanical problem. The aim of this paper is to extensively review the potential back pain generators in FBSS patients and to discuss their respective roles and interactions in back pain pathophysiology. METHODS: Literature searches included an exhaustive review of 643 references and 74 book chapters updated by searching the major electronic databases from 1930 to August 2013. RESULTS: Nociceptive fibres innervating any of the back anatomical structures can all play a part in the pathogenesis of the low back pain component in FBSS. The main spinal pain generators are not only myofascial syndrome or muscle spasm but also the facets, the disc complex or a sagittal imbalance and should therefore be carefully reviewed. Only after these steps and appropriate imaging, would it be justified to irremediably diagnose the patient with a refractory chronic condition, requiring no further spine surgery and to propose "palliative" pain treatment options. CONCLUSION: Clinical investigations of the low back pain component in FBSS patients should be based on meticulous dissection of all potential triggers that could be a source of the nociceptive pain characteristics and possibly amenable to further aetiological treatment. Clinicians should therefore refine pain management strategies to ensure that the chronic nature of the pain becomes the guiding principle for multidisciplinary assessment.

From "mechanical" to "neuropathic" back pain concept in FBSS patients. A systematic review based on factors leading to the chronification of pain (part C).

INTRODUCTION: Beyond initial lesions, any form of spinal (re)operation can cause direct potential aggression to the nervous system by contact with neural tissue or by imprinting a morphological change on the neural tissue. The potential consequences of nerve root injury affect both peripheral and axial dermatomal distribution. The hypothesis of a possible neuropathic aspect associated with the back pain component of failed back surgery syndrome (FBSS) therefore appears to be reasonable. Its pathophysiology remains unclear due to the permanent interplay between nociceptive and neuropathic pain components, resulting in the coexistence of physiological and pathological pain at the same anatomical site. This paper is designed to extensively review the fundamental mechanisms leading to chronification of pain and to suggest considering the emerging concept of "neuropathic back pain". METHODS: Literature searches included an exhaustive review of 643 references and 74 book chapters updated by searching the major electronic databases from 1930 to August 2013. RESULTS: Inflammatory and neuropathic back pain could be distinguished from pure nociceptive pain as a result of an increased activity and responsiveness of sensitized receptors at the peripheral nervous system and also as a consequence of increased afferent inflow to the central nervous system, moving to a new, more excitable "wind-up" state. This can be clinically translated to an amplified response to a moderate/intense stimulus (primary hyperalgesia) or an aversive sensation provoked by the activation of low-threshold mechanoreceptors through non-noxious stimuli, which defines allodynia. Activated non-neuronal cells including microglia have been found to be cellular intermediaries in mechanical allodynia. Major changes in the spinal cord are the loss of inhibitory mechanisms, resulting in an increased activity of interneurons or projection neurons and a structural reorganization of the central projection pattern. This abnormal excitability of sensory neurons is coupled to changes in the neurotransmitter phenotype, which could induce a resistance to conventional analgesic treatments. CONCLUSION: A clear understanding of the factors leading to the chronification of back pain should help us to move to the choice of mechanism related pain treatments to improve outcomes in FBSS chronic condition.

[Neurosurgical treatment of chronic pain]. / Traitement neurochirurgical de la douleur chronique.

Neurosurgical treatment of pain used two kind of techniques: 1) Lesional techniques interrupt the transmission of nociceptive neural input by lesionning the nociceptive pathways (drezotomy, cordotomy, tractotomy…). They are indicated to treat morphine-resistant cancer pain and few cases of selected neuropathic pain. 2) Neuromodulation techniques try to decrease pain by reinforcing inhibitory and/or to limit activatory mechanisms. Chronic electrical stimulation of the nervous system (peripheral nerve stimulation, spinal cord stimulation, motor cortex stimulation…) is used to treat chronic neuropathic pain. Intrathecal infusion of analgesics (morphine, ziconotide…), using implantable pumps, allows to increase their efficacy and to reduce their side effects. These techniques can improve, sometimes dramatically, selected patients with severe and chronic pain, refractory to all other treatments. The quality of the analgesic outcome depends on the relevance of the indications.

Role of radiosurgery in the management of pineal region tumours: indications, method, outcome.

Numerous tumour types can occur in the pineal region. Because these tumours are uncommon and heterogeneous, it is often difficult to establish optimal treatment strategies based on comparative clinical trials. To date, the role of radiosurgery for the treatment of pineal region tumours remains controversial. This report of a 10-year single-department experience and review of the literature focuses on the spectrum of pathologic features found in these pineal parenchymal tumours and on the interest of radiosurgery in their management. Considering pineocytomas, although these tumours have been considered to be radioresistant to fractionated radiotherapy, our results are in agreement with similar results reported in the literature in suggesting that radiosurgery may be an alternative to surgical resection or an adjuvant therapy when the resection is not optimal. When dissemination occurs after radiosurgery, however, craniospinal radiation and chemotherapy are necessary. Radiosurgery has also proven its interest in the treatment of germinomas as an alternative to encephalic radiotherapy with limited long-term damage. Regarding the other pathologies, radiosurgery can be considered as part of a multimodal treatment including surgery, chemo-radiotherapy and its role still has to be clearly defined.

Endoscopic versus stereotactic procedure for pineal tumour biopsies: Comparative review of the literature and learning from a 25-year experience.

BACKGROUND AND PURPOSE: Pineal tumours account for 1% to 4% of brain tumours in adults and for around 10% in children. Except in a few cases where germ cell markers are elevated, accurate histological samples are mandatory to initiate the treatment. Open surgery still has a high morbidity and is often needless. Biopsies can either be obtained by endoscopic or stereotactic procedures. METHODS: Following an extensive review of the literature (PubMed 1970-2013; keywords pineal tumour, biopsy; English and French), 33 studies were analysed and relevant data compared regarding the type of procedure, diagnosis rate, cerebrospinal fluid diversion type and rate, perioperative mortality, morbidity. RESULTS: Endoscopic and stereotactic biopsies showed a diagnosis rate of 81.1% (20%-100%) and 93.7% (82%-100%), respectively. Endoscopic biopsies involved 21.0% of minor and 2.0% of major complications whereas stereotactic biopsies involved 6.4% of minor and 1.6% of major complications. The most frequently reported complication was haemorrhage for both endoscopic and stereotactic procedures, accounting for 4.8% and 4.3%, respectively. Mortality rate was low for both endoscopic and stereotactic procedures, equal to 0.4% and 1.3%, respectively. Local experience of stereotactic biopsies was also reported and corroborated the previous data. CONCLUSIONS: The difference between both procedures is not statistically significant (p>0.05) across large series (≥20patients). Nevertheless, tissue diagnosis appears less accurate with endoscopic procedures than with stereotactic procedures (81.1% versus 93.7%, weighted mean across all series). In our opinion, the neuroendoscopic approach is the best tool for managing hydrocephalus, whereas stereotactic biopsies remain the best way to obtain a tissue diagnosis with accuracy and low morbidity.

Multicolumn spinal cord stimulation for significant low back pain in failed back surgery syndrome: design of a national, multicentre, randomized, controlled health economics trial (ESTIMET Study).

BACKGROUND: Many studies have demonstrated the efficacy of spinal cord stimulation (SCS) for chronic neuropathic radicular pain over recent decades, but despite global favourable outcomes in failed back surgery syndrome (FBSS) with leg pain, the back pain component remains poorly controlled by neurostimulation. Technological and scientific progress has led to the development of new SCS leads, comprising a multicolumn design and a greater number of contacts. The efficacy of multicolumn SCS lead configurations for the treatment of the back pain component of FBSS has recently been suggested by pilot studies. However, a randomized controlled trial must be conducted to confirm the efficacy of new generation multicolumn SCS. Évaluation médico-économique de la STImulation MEdullaire mulTi-colonnes (ESTIMET) is a multicentre, randomized study designed to compare the clinical efficacy and health economics aspects of mono- vs. multicolumn SCS lead programming in FBSS patients with radicular pain and significant back pain. MATERIALS AND METHODS: FBSS patients with a radicular pain VAS score≥50mm, associated with a significant back pain component were recruited in 14 centres in France and implanted with multicolumn SCS. Before the lead implantation procedure, they were 1:1 randomized to monocolumn SCS (group 1) or multicolumn SCS (group 2). Programming was performed using only one column for group 1 and full use of the 3 columns for group 2. Outcome assessment was performed at baseline (pre-implantation), and 1, 3, 6 and 12months post-implantation. The primary outcome measure was a reduction of the severity of low back pain (bVAS reduction≥50%) at the 6-month visit. Additional outcome measures were changes in global pain, leg pain, paraesthesia coverage mapping, functional capacities, quality of life, neuropsychological aspects, patient satisfaction and healthcare resource consumption. TRIAL STATUS: Trial recruitment started in May 2012. As of September 2013, all 14 study centres have been initiated and 112/115 patients have been enrolled. Preliminary results are expected to be published in 2015. TRIAL REGISTRATION: Clinical trial registration information-URL: www.clinicaltrials.gov. Unique identifier NCT01628237.