Publications by authors named "André Truffert"

27 Publications

  • Page 1 of 1

Early advance care planning in amyotrophic lateral sclerosis patients: results of a systematic intervention by a palliative care team in a multidisciplinary management programme - a 4-year cohort study.

Swiss Med Wkly 2021 Mar 18;151:w20484. Epub 2021 Mar 18.

Palliative Care Consultation, Division of Palliative Medicine, Department of Rehabilitation and Geriatrics, Geneva University Hospitals, Switzerland / Unit for Development and Research in Medical Education (UDREM), Faculty of Medicine, University of Geneva, Switzerland.

Introduction: Although recommended, the implementation of early advance care planning is suboptimal in amyotrophic lateral sclerosis (ALS) patients. Barriers to advance care planning include healthcare professionals’ and patients’ reluctance, and uncertainty about the right time to initiate a discussion.

Aim Of The Study: To determine how often advance care planning was initiated, and the content of the discussion in a first routine palliative care consultation integrated within a multidisciplinary management programme.

Methods: Between June 2012 and September 2016, a prospective cohort study was conducted in Geneva University Hospitals. Sixty-eight patients were seen every 3 months for a 1-day clinical evaluation in a day care centre.

Results: The patients’ mean ± standard deviation age was 68.6 ± 11.9 years, 50% were women. Four patients were excluded because of dementia. Advance care planning was initiated with 49 (77%) patients in the first palliative care consultation. Interventions most often addressed were cardiopulmonary resuscitation (49%), intubation and tracheostomy (47%) and palliative sedation (36.7%). Assisted suicide was discussed with 16 patients (36.6%). Functional disability was the only factor associated with initiation of advance care planning. Nearly half of the patients wrote advance directives (45%) or designated a healthcare surrogate (41%). Bulbar onset, functional disability and noninvasive ventilation were not associated with the completion of advance directives.

Conclusion: Early initiation of advance care planning is feasible in most ALS patients during a routine consultation, and relevant treatment issues can be discussed. All ALS patients should be offered the opportunity to write advance directives as completion was not associated with disease severity. .
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http://dx.doi.org/10.4414/smw.2021.20484DOI Listing
March 2021

Does impaired conduction of Ia afferents explain early tendon areflexia in Guillain-Barré Syndrome?

Clin Neurophysiol 2021 01 16;132(1):104-105. Epub 2020 Nov 16.

Faculty of Medicine, Geneva University, Geneva, Switzerland.

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http://dx.doi.org/10.1016/j.clinph.2020.11.004DOI Listing
January 2021

Sporadic late onset nemaline myopathy with monoclonal gammopathy of undetermined significance: two cases with long term stability.

Eur J Transl Myol 2020 Sep 16;30(3):9225. Epub 2020 Sep 16.

Neuroimmunology and Neuromuscular Unit, Department of Clinical Neurosciences, Geneva University Hospital, Geneva, Switzerland.

Monoclonal gammopathy of undetermined significance (MGUS) associated to sporadic late onset nemaline myopathy (SLONM) is a rare and severely disabling condition of quickly progressive limb girdle acquired myopathy. It is believed by some authors to be due to myotoxicity of light chain deposits. Two female patients were diagnosed with MGUS associated SLONM. In the first case, diagnosis was delayed by 6 years thus giving time for a severe generalized myopathy and cardiomyopathy to develop. A single anti-myeloma chemotherapy with lenalidomide markedly improved and stabilized the patient's condition despite respiratory and cardiac insufficiency. In our second patient the condition was identified one year after onset of the first symptom and markedly improved after autologous bone marrow transplantation and lenalidomide. Clinicians should be aware of monoclonal gammopathy associated sporadic late onset nemaline myopathy as this acquired muscle disorder, although extremely rare, may be reversed by adequate management.
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http://dx.doi.org/10.4081/ejtm.2020.9225DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7582403PMC
September 2020

Impaired conduction of Ia sensory fibers in multifocal motor neuropathy: An electrophysiological demonstration.

Clin Neurophysiol Pract 2020 7;5:152-156. Epub 2020 Aug 7.

Division of Neurology, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland.

Objectives: To report the clinical and electrophysiological findings in two patients with multifocal motor neuropathy (MMN) and bilateral absent patellar and Achilles tendon reflexes despite normal strength of quadriceps and calf muscles.

Methods: The medical history and clinical evaluation were completed by electrophysiological tests: sensory and motor nerve conduction studies, needle electromyography, motor-evoked potentials (MEPs) after transcranial magnetic stimulation, patellar T (tendon) responses, quadriceps and soleus H (Hoffman) reflex recordings.

Results: In the two patients, history, clinical evaluation, nerve conduction studies, favorable response to intravenous immunoglobulins, and positive anti-GM1 antibodies fulfilled the diagnosis of MMN. The lower limbs were asymptomatic, except for a unilateral weakness of foot dorsiflexion. The patellar and Achilles tendon reflexes disappeared during the course of the disease. The sensory nerve conduction studies were normal or minimally modified, M-wave and MEP/M amplitude ratio to the quadriceps were normal, patellar T (tendon) responses were virtually absent, and H-reflex to the quadriceps and soleus muscles were absent.

Conclusions: These observations, which show the interruption of the reflex afferent pathway, raise the question of Ia afferent involvement in the lower limbs of these two patients with MMN. Further investigations should determine the frequency and significance of these findings in this disorder.
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http://dx.doi.org/10.1016/j.cnp.2020.07.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473831PMC
August 2020

Multidisciplinary care in amyotrophic lateral sclerosis: a 4-year longitudinal observational study.

Swiss Med Wkly 2020 Jun 9;150:w20258. Epub 2020 Jun 9.

Division of Pulmonary Diseases, Department of Medicine, Geneva University Hospitals, Geneva, Switzerland / Faculty of Medicine, University of Geneva, Switzerland.

Over a four-year period, ALS patients complied with the modalities of the multidisciplinary management follow-up without any drop-outs. The multidisciplinary management structure also contributes to increasing the experience and knowledge of the clinicians involved in managing patients suffering from this rare disease.
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http://dx.doi.org/10.4414/smw.2020.20258DOI Listing
June 2020

Symptomatic tandem spinal stenosis: a clinical, diagnostic, and surgical challenge.

Neurosurg Rev 2020 Oct 13;43(5):1289-1295. Epub 2019 Aug 13.

Neurosurgical Unit, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland.

Tandem spinal stenosis (TSS) is an entity which refers to spinal canal diameter narrowing in at least two distinct regions of the spine. When symptomatic, management of TSS is controversial. In this study, we present a consecutive series of patients with symptomatic TSS and report diagnostic and surgical challenges. We retrospectively reviewed a consecutive series of N = 8 patients with symptomatic TSS who underwent surgical treatment in at least one region of the spine. Patients presented with multiple complaints, including neurogenic claudication, progressive gait disturbances, and signs of radiculopathy and/or myelopathy, among others. Modified Japanese Orthopedic Association (mJOA) and Oswestry Low Back Pain Disability Questionnaire (ODI) were obtained in pre- and postoperative period. Electroneurophysiological examinations were limited to patients whose clinical and radiological signs were not sufficient to determine which region was more affected. From 2015 to 2018, we included N = 8 consecutive patients with TSS who underwent surgery by a staged approach. The stenosis was localized in the cervical and lumbar region in six patients (75%) and in the cervical, dorsal, and lumbar level (triple TSS) in two patients (25%). Four patients (50%) underwent cervical and lumbar surgery, two (25%) underwent cervical surgery alone, and two (25%) were operated in all three involved regions. Surgical treatment allowed an improvement of the mean mJOA score (from 12.5/17 to 15/17) and mean ODI score (from 41 to 28%). TSS represents a clinical, diagnostic, and surgical challenge. We recommend to systematically obtain electrophysiological and radiological examinations and then to perform a staged surgery, beginning at the most symptomatic region.
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http://dx.doi.org/10.1007/s10143-019-01154-9DOI Listing
October 2020

Predicting respiratory failure in amyotrophic lateral sclerosis: still a long way to go.

Eur Respir J 2019 Aug 1;54(2). Epub 2019 Aug 1.

Division of Pulmonary Diseases, Dept of Medicine, Geneva University Hospitals, Geneva, Switzerland.

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http://dx.doi.org/10.1183/13993003.01065-2019DOI Listing
August 2019

Contraction response to muscle percussion: A reappraisal of the mechanism of this bedside test.

Clin Neurophysiol 2018 01 28;129(1):51-58. Epub 2017 Oct 28.

Division of Neurology, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland. Electronic address:

Objective: To study whether the contraction evoked by muscle percussion stems from the excitation of the muscle or of the nerve and to discuss the changes of this response in neuromuscular disorders.

Methods: In 30 neurologically healthy patients undergoing surgery (for ear, nose, or throat problems unrelated to the study) under general anesthesia with propofol and sufentanil we measured with an electrogoniometer the maximal dorsiflexion of the ankle evoked by reflex hammer percussion of the tibialis anterior muscle before and under neuromuscular junction blockade with rocuronium bromide. In 3 additional healthy volunteers we searched for F-waves to disclose whether percussion excites axons within the muscle.

Results: Responses from 28 neurologically healthy patients (15 women) were analyzed after exclusion of 2 due to technical problems. Mean age (SD) was 28 (9) years. Maximal dorsiflexion of the ankle was not significantly modified by neuromuscular junction blockade (mean difference 0.01 mV [95%CI, -0.07 to 0.08], p=0.879). Muscle percussion evoked F-waves in the 3 healthy volunteers tested.

Conclusions: Maximal contraction response to muscle percussion has a muscular rather than a neural origin. However, percussion also excites axons within the muscle.

Significance: These findings may provide clues to understand the changes observed in neuromuscular disorders.
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http://dx.doi.org/10.1016/j.clinph.2017.10.013DOI Listing
January 2018

A modern multidisciplinary approach to patients suffering from cervical spondylotic myelopathy.

J Neurosurg Sci 2019 Feb 13;63(1):19-29. Epub 2016 May 13.

Neurosurgical Unit, Geneva University Hospitals, Faculty of Medicine, Medical School, University of Geneva, Geneva, Switzerland.

Background: The traditional approach to patients suffering from cervical spondylotic myelopathy (CSM) consists of mere assessment of radiological standard magnetic resonance (MR) images and evaluation of surgical indication, depending on clinical symptoms and degree of radiological stenosis. Identification of prognostic factors for surgery remains difficult. Surgery is thought to be able to stop the disease progression, while significant improvements of neurological symptoms are not predictable.

Methods: Authors present a modern approach to patients with CSM, that is comprehensive of clinical, electrophysiological and radiological findings, and that has been developed by a multidisciplinary team of experts (neurosurgeons, neurologists, neuroradiologists). Authors tried to identify the good responders to surgery, as those who really improved symptoms, by performing an integration of these data. This approach has been used in 11 consecutive patients suffering from and operated for CSM at our Institution. The multidisciplinary protocol included the complementary use of electrophysiological (motor and somatosensory evoked potentials), radiological (magnetic resonance, cervical plain and dynamic x-rays), and clinical (modified Japanese Orthopedic Association [mJOA] and Neck Disability Index [NDI] scores, Hirabayashi Recovery Ratio) values. These data were obtained at the preoperative period, and at 3 and 12 months follow-up. We defined as "good responders" those patients having had an improvement of the Hirabayashi Recovery Ratio of 50% and of the NDI of 30%.

Results: The mean preoperative mJOA was 12.79 (range 3-17), while the mean mJOA at 3 and 12 months was, respectively, 14.71 and 13.43. However, only the improvement at 3 months was statistically significant, while improvements from the preoperative assessment to 12 months and from 3 to 12 months were not significant. The mean preoperative NDI was 33.57%, while it was 32.43% and 24.36% at 3 and 12 months, respectively. None of these improvements was significant. Concerning response to surgery, we observed 7/11 (63.3%) good responders according to the Hirabayashi Recovery Ratio, and 6/11 (54.5%) good responders according to NDI results.

Conclusions: A modern multidisciplinary approach to patients with CSM is mandatory to investigate the different aspects of the disease. Decompressive surgery was able, in our series, to improve or stabilize clinical symptoms. Further studies are necessary to allow for a proper selection of patients by cumulative analysis of multidisciplinary findings.
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http://dx.doi.org/10.23736/S0390-5616.16.03724-3DOI Listing
February 2019

Ryanodine receptor fragmentation and sarcoplasmic reticulum Ca2+ leak after one session of high-intensity interval exercise.

Proc Natl Acad Sci U S A 2015 Dec 2;112(50):15492-7. Epub 2015 Nov 2.

Department of Physiology and Pharmacology, Karolinska Institutet, SE 171 77 Stockholm, Sweden; Sports Science and Innovation Institute, Lithuanian Sports University, LT-44221 Kaunas, Lithuania;

High-intensity interval training (HIIT) is a time-efficient way of improving physical performance in healthy subjects and in patients with common chronic diseases, but less so in elite endurance athletes. The mechanisms underlying the effectiveness of HIIT are uncertain. Here, recreationally active human subjects performed highly demanding HIIT consisting of 30-s bouts of all-out cycling with 4-min rest in between bouts (≤3 min total exercise time). Skeletal muscle biopsies taken 24 h after the HIIT exercise showed an extensive fragmentation of the sarcoplasmic reticulum (SR) Ca(2+) release channel, the ryanodine receptor type 1 (RyR1). The HIIT exercise also caused a prolonged force depression and triggered major changes in the expression of genes related to endurance exercise. Subsequent experiments on elite endurance athletes performing the same HIIT exercise showed no RyR1 fragmentation or prolonged changes in the expression of endurance-related genes. Finally, mechanistic experiments performed on isolated mouse muscles exposed to HIIT-mimicking stimulation showed reactive oxygen/nitrogen species (ROS)-dependent RyR1 fragmentation, calpain activation, increased SR Ca(2+) leak at rest, and depressed force production due to impaired SR Ca(2+) release upon stimulation. In conclusion, HIIT exercise induces a ROS-dependent RyR1 fragmentation in muscles of recreationally active subjects, and the resulting changes in muscle fiber Ca(2+)-handling trigger muscular adaptations. However, the same HIIT exercise does not cause RyR1 fragmentation in muscles of elite endurance athletes, which may explain why HIIT is less effective in this group.
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http://dx.doi.org/10.1073/pnas.1507176112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4687604PMC
December 2015

Anti-TNF alpha medications and neuropathy.

J Peripher Nerv Syst 2015 Dec;20(4):397-402

Nerve-Muscle Unit, Department of Clinical Neurosciences, Lausanne University Hospital (CHUV), Lausanne, Switzerland.

We studied the clinical, electrophysiological, and pathological features, outcome, and frequency of anti-tumor necrosis factor alpha (a-TNF) medications-induced neuropathies (ATIN) in patients with inflammatory disorders. Of 2,017 patients treated with a-TNF medication, 12 patients met our inclusion criteria for a prevalence of 0.60% and an incidence of 0.4 cases per 1,000 person-years. The median time from a-TNF medication treatment to ATIN was 16.8 months (range 2-60 months). Six patients had focal or multifocal peripheral neuropathies. The other six had generalized neuropathies. For all, a-TNF medication was stopped. Seven patients received immunoglobulin infusions. ATIN outcome was favorable in all but one patient. ATINs are rare and heterogeneous neuropathies. In 10 patients, the neuropathy was "inflammatory", suggesting that it could be due to systemic pro-inflammatory effects of a-TNF agents.
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http://dx.doi.org/10.1111/jns.12147DOI Listing
December 2015

Acute painful diabetic neuropathy: an uncommon, remittent type of acute distal small fibre neuropathy.

Swiss Med Wkly 2015 5;145:w14131. Epub 2015 May 5.

Department of Neurology, Geneva University Hospital, Switzerland.

Introduction: Acute painful diabetic neuropathy (APDN) is a distinctive diabetic polyneuropathy and consists of two subtypes: treatment-induced neuropathy (TIN) and diabetic neuropathic cachexia (DNC). The characteristics of APDN are (1.) the small-fibre involvement, (2.) occurrence paradoxically after short-term achievement of good glycaemia control, (3.) intense pain sensation and (4.) eventual recovery. In the face of current recommendations to achieve quickly glycaemic targets, it appears necessary to recognise and understand this neuropathy.

Methods And Results: Over 2009 to 2012, we reported four cases of APDN. Four patients (three males and one female) were identified and had a mean age at onset of TIN of 47.7 years (±6.99 years). Mean baseline HbA1c was 14.2% (±1.42) and 7.0% (±3.60) after treatment. Mean estimated time to correct HbA1c was 4.5 months (±3.82 months). Three patients presented with a mean time to symptom resolution of 12.7 months (±1.15 months). One patient had an initial normal electroneuromyogram (ENMG) despite the presence of neuropathic symptoms, and a second abnormal ENMG showing axonal and myelin neuropathy. One patient had a peroneal nerve biopsy showing loss of large myelinated fibres as well as unmyelinated fibres, and signs of microangiopathy.

Conclusions: According to the current recommendations of promptly achieving glycaemic targets, it appears necessary to recognise and understand this neuropathy. Based on our observations and data from the literature we propose an algorithmic approach for differential diagnosis and therapeutic management of APDN patients.
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http://dx.doi.org/10.4414/smw.2015.14131DOI Listing
January 2016

Multifocal motor neuropathy with high titers of anti-MAG antibodies.

J Peripher Nerv Syst 2014 Jun;19(2):180-2

Department of Clinical Neurosciences, Division of Neurology, Geneva University Hospital, Geneva, Switzerland.

Multifocal motor neuropathy (MMN) and anti-myelin-associated glycoprotein (anti-MAG)-associated neuropathy are clinically and electrophysiologically distinct entities. We describe a patient with characteristic features of both neuropathies, raising the possibility of an overlap syndrome. A 49-year-old patient reported a history of slowly progressive predominantly distal tetraparesis, with mild sensory deficits. Nerve conduction studies demonstrated persistent motor conduction blocks outside compression sites, typical of MMN. Laboratory findings revealed persistently high titers of anti-MAG immunoglobulin Mλ (IgMλ) paraprotein in the context of a monoclonal gammapathy of unknown significance. Skin biopsy of distal lower limb revealed IgM positive terminal nerve perineurium deposits. This case suggests that the distinction between subtypes of chronic inflammatory neuropathies may not be as clear as initially thought, and that the pattern of pathogenicity of anti-MAG antibodies may vary.
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http://dx.doi.org/10.1111/jns5.12069DOI Listing
June 2014

Giant plexiform neurofibroma in neurofibromatosis type 1.

Arch Neurol 2010 Mar;67(3):356-7

Department of Neurology, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva 14, Switzerland.

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http://dx.doi.org/10.1001/archneurol.2009.338DOI Listing
March 2010

Experimental study of a late response recorded from the thoracic wall after phrenic nerve stimulation.

Clin Neurophysiol 2009 Aug 3;120(8):1543-7. Epub 2009 Jul 3.

CHU Nantes, Laboratoire d'Explorations Fonctionnelles, Nantes, France.

Objectives: The phrenic nerve cervical stimulation induces an early motor diaphragmatic M response that may be recorded from the 7th ipsilateral intercostal space (ICS). Some responses with prolonged latency and of unclear origin can be recorded from the same recording site. The aim of the study was to determine the electrophysiological characteristics and the neuroanatomical pathways underlying the long-latency responses (LLRs) recorded from the 7th ICS.

Methods: We studied seven healthy volunteers, five patients with spinal cord injury and five patients with diaphragmatic palsy. All underwent phrenic nerve conduction study. An LLR was sought for at different stimulation sites using various stimulus intensities.

Results: A polyphasic LLR was recorded from the 7th ICS in all healthy subjects. It was mainly elicited by nociceptive stimulations, not only of the phrenic, but also of the median nerves. Its latency was longer than 70ms, with a wide inter- and intra-individual variability. Amplitude was highly variable and some habituation phenomenon occurred. The LLR was retained in most tetraplegic patients after phrenic nerve stimulation, but absent otherwise. It was present in all patients with diaphragmatic palsy after phrenic nerve stimulation.

Conclusion: The LLR is likely to be produced by both intercostal and diaphragm muscles. It is a polysynaptic and multisegmental spinal response, probably conveyed by small-diameter nociceptive A-delta and/or C fibres and modulated by a supraspinal control.

Significance: The LLR recorded from the chest wall may constitute, by analogy with the nociceptive component of the lower limb flexion reflex in humans, a protective and withdrawal spinal reflex response.
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http://dx.doi.org/10.1016/j.clinph.2009.06.004DOI Listing
August 2009

Peripheral autoimmune neuropathy assessed using corneal in vivo confocal microscopy.

Arch Neurol 2009 Mar;66(3):403-5

Department of Clinical Neurosciences, Geneva University Hospital, Geneva, Switzerland.

Background: Corneal nerves can be examined using in vivo confocal microscopy (IVCM). This new technique permits sequential observation of the corneal subbasal nerve plexus and detects early signs of diabetic peripheral neuropathy.

Objective: To describe a patient with autoimmune peripheral neuropathy followed up using corneal IVCM.

Design: Case report.

Setting: Clinic of neurology, Geneva, Switzerland. Patient A 56-year-old man with peripheral neuropathy diagnosed as anti-myelin-associated glycoprotein neuropathy. His symptoms initially worsened despite the administration of intravenous immunoglobulins and plasma exchange. Evolution was eventually favorable after rituximab and corticosteroids were given. At 1-year follow-up, clinical recovery was almost complete, and the patient was stable according to the results of clinical and electrophysiologic assessments. Main Outcome Measure Corneal nerve measurement by IVCM.

Results: Examination of corneal nerves using IVCM at 2 different times during the patient's clinical evolution (peak disease and recovery phase) demonstrated histologic signs that correlated with the results of clinical and electrophysiologic assessments.

Conclusion: This observation supports the hypothesis that corneal IVCM could also be helpful for the early detection or follow-up of autoimmune peripheral neuropathy.
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http://dx.doi.org/10.1001/archneurol.2008.587DOI Listing
March 2009

Mild clinical expression of Lambert-Eaton myasthenic syndrome in a patient with HIV infection.

BMJ Case Rep 2009 23;2009. Epub 2009 Jan 23.

University Hospital of Geneva, Micheli-du-Crest 24, Geneva 14, 1211, Switzerland.

Neuromuscular complications of HIV are related to immunodeficiency, direct cytotoxicity of the virus or side effect of the treatments. Autoimmune disorders involving the nervous system, including Guillain-Barre syndrome, myositis and vasculitis, have been described in association with HIV. Neuromuscular junction autoimmune diseases such as myasthenia gravis have been occasionally reported in patients with HIV, whereas the Lambert-Eaton myasthenic syndrome (LEMS) has never been described. We report an unusual case of paucisymptomatic LEMS in a patient with HIV infection.
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http://dx.doi.org/10.1136/bcr.08.2008.0649DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3028063PMC
November 2011

A clinical study of corticospinal and peripheral conductions to proximal lower limb muscles.

Clin Neurophysiol 2007 Aug 22;118(8):1824-34. Epub 2007 Jun 22.

Geneva University, Service de Neurologie, Unité ENMG et des Affections Neuromusculaires, Hópitaux Universitaires de Genéve, Switzerland.

Objective: To investigate the clinical utility of the newly developed "quadriceps combined technique" (QCT), which provides a global evaluation of the central and peripheral conduction to the proximal muscles of lower limbs, in a variety of central and peripheral neurological disorders.

Methods: Using surface recordings from the vastus medialis of the quadriceps muscle, we analyzed amplitudes and latencies of M response, patellar T reflex and motor evoked potentials (MEPs) after transcranial magnetic stimulation. We studied 180 patients with disorders impairing proximal strength of one or both lower limbs and compared them with 100 controls reported previously.

Results: The best parameters to detect central motor disorders were the central motor conduction time, MEP/M amplitude, T/MEP amplitude and latency ratios, whereas peripheral motor conduction time (PMCT) was best to assess peripheral disorders. The best parameter to identify proximal peripheral disorder was PMCTprox, whereas for distal peripheral disorders M amplitude and T/MEP amplitude ratio were most discriminative.

Conclusions: We report a simple, rapidly performed and well-tolerated method that improves proximal lower limbs evaluation, helps distinguishing pathologic from physiological brisk reflexes and provides clues for etiologic diagnosis.

Significance: The QCT is a sensitive and specific tool to investigate central and peripheral neurological disorders.
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http://dx.doi.org/10.1016/j.clinph.2007.05.063DOI Listing
August 2007

[Leprosy, a neurologic disease].

Rev Med Suisse 2007 May;3(110):1178, 1180-4

Service de Neurologie, Policlinique de Neurologie, Département de médecine communitaire et de premier recours, HUG, 1211 Genève 14.

Leprosy is a treatable chronic infectious disease, caused by Mycobacterium leprae, not highly transmittable that affects mainly the skin and peripheral nerves. Often neglected because it is rare in western countries, it may be encountered in patients coming back from endemic areas. Diagnostic criteria include underpigmented patches with loss of sensation, thickened peripheral nerves and acid-fast bacilli on skin smears or biopsy material. The variation of the cellular immune response determines the different forms of the disease (tuberculoid to lepromatous) and the neurological impairment. A precise diagnosis is mandatory to adjust the treatment. Among the neurological complications the leprosy reactions are the most important because they may result in increased nerve damage and compromised recovery if the specific treatment is delayed.
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May 2007

[Sensory neuropathies].

Rev Med Suisse 2007 May;3(110):1160-3

Unité d'electroneuromyographie et des affections neuromusculaires, Service de neurologie, HUG, 1211 Genève 14.

Peripheral sensory neuropathies are rare. Their clinical and electrophysiological pictures vary mainly with the course of the disorder (acute, subacute or chronic), with the size of the nerve fibres (large or small diameter) and the nervous structure involved (sensory axon or dorsal root ganglion). We discuss the characteristics and aetiologies of the various sensory neuropathies. Clinical case reports underline the practical aspects of these disorders.
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May 2007

Electrophysiological evaluation of motor pathways to proximal lower limb muscles: a combined method and reference values.

Clin Neurophysiol 2007 Mar 16;118(3):513-24. Epub 2007 Jan 16.

Kaunas University of Medicine, Kaunas, Lithuania.

Objective: In contrast with their important functional and clinical role, motor pathways to proximal muscles of lower limbs are rarely investigated in clinical neurophysiology. We describe a method to evaluate central and peripheral pathways to these muscles and report reference values.

Methods: Recording of both quadriceps was performed in 100 subjects. We analyzed the maximal M response after electrical stimulation of the femoral nerve, the patellar T reflex and the motor evoked potential (MEP) after transcranial magnetic stimulation. We defined the central motor conduction time as the difference between the MEP latency and the peripheral motor conduction time, estimated as the half of the T latency minus 0.5ms.

Results: The mean MEP latency is 20.6ms (SD 1.99ms), central motor conduction time 10.1ms (SD 1.29ms), MEP/M amplitude ratio 60.0% (SD 15.75%). Normal limits according to height and age are provided for each parameter and for interside asymmetry.

Conclusions: This method to investigate the central and peripheral motor pathways supplying the L2-L4 myotomes is simple, painless and rapidly performed. The T reflex provides additional information on the proximal sensory pathways.

Significance: This method will be useful in many clinical conditions.
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http://dx.doi.org/10.1016/j.clinph.2006.11.006DOI Listing
March 2007

Myasthenia gravis associated with HTLV-I infection and atypical brain lesions.

Muscle Nerve 2007 Apr;35(4):525-8

Department of Neurosciences, Clinic of Neurology, University Hospital of Geneva, Micheli-du-Crest 24, 1211 Geneva 14, Switzerland.

We report a patient who experienced progressive diplopia and distal weakness of the upper limbs. Magnetic resonance imaging of the brain showed extensive white matter lesions and analysis of cerebrospinal fluid revealed acute human T-lymphotropic virus type I (HTLV-I) infection. Myasthenia gravis (MG) was evidenced by electromyography (EMG) and antibodies against acetylcholine receptor. This unusual case of MG associated with HTLV-I infection and brain-restricted lesions underscores the possible link between viruses and MG pathogenesis.
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http://dx.doi.org/10.1002/mus.20694DOI Listing
April 2007

Electrophysiology of small peripheral nerve fibers in man. A study using the cutaneous silent period.

Medicina (Kaunas) 2006 ;42(4):300-13

Department of Neurology, Kaunas University of Medicine, Lithuania.

Unlabelled: Methods for assessing small peripheral nerve fiber function objectively are limited. The cutaneous silent period (CuSP), a transient suppression of electromyographic voluntary activity that follows painful stimuli, could serve as an objective functional measure of the A delta fibers.

Objectives: To establish normal values of CuSP, to compare these values to those in the literature and to discuss the yield of the CuSP in pathological conditions.

Material And Methods: We investigated the CuSP of the upper and lower limbs of 40 normal subjects.

Results: We observed that the spinal circuitry mediating the CuSP is mainly unilateral and restricted to one limb, and that CuSP latency decreases and duration increases with increasing stimulus intensity, then CuSP stabilizes with strong stimuli. In an additional study, we observed that painful cutaneous stimuli are either inhibitory, causing a pause in an ongoing contraction (CuSP), or excitatory, inducing a contraction of a muscle at rest (RIII). Inhibition and excitation have similar timings.

Conclusion: The method for studying the CuSP is simple and well tolerated; it is useful to study A delta fibers in peripheral neuropathies and the central circuitry of this cutaneous nociceptive response in conditions affecting the spinal cord. Comparison of CuSP studies suggests the need for a standardization of the method.
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May 2006

Cutaneous silent period in carpal tunnel syndrome.

Muscle Nerve 2006 Apr;33(4):487-93

Neurology Clinic, Kaunas University of Medicine, Kaunas, Lithuania.

The cutaneous silent period (CuSP), a transient suppression of electromyographic activity that follows painful stimuli, allows an indirect study of the small-diameter A-delta fibers. To assess the function of these fibers in peripheral nerve disorders, we compared the CuSP of 40 controls to that of 40 patients with carpal tunnel syndrome (CTS) and one patient with a traumatic transection of the median nerve. Patients with CTS were divided into three severity groups, based on electrophysiological data. In CTS, digit 2 evoked CuSP onset latency was increased in all groups, and CuSP duration from abductor digiti minimi was reduced in all groups. In our series, although some parameters of the CuSP were altered, only transection of the nerve abolished it. A-delta fibers are robust, probably due to their less vulnerable small diameter. This characteristic may be useful to study various conditions and essential for patients to retain some sensation within the median nerve territory.
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http://dx.doi.org/10.1002/mus.20496DOI Listing
April 2006

Transcranial magnetic stimulation in clinical practice.

Medicina (Kaunas) 2005 ;41(10):813-24

Clinic of Neurology, Kaunas University of Medicine, Kaunas, Lithuania.

Transcranial magnetic stimulation allows a non-invasive and painless stimulation of the human brain and cranial nerves. The method is in use since 1985. Transcranial magnetic stimulation can use single stimuli, pairs of stimuli separated by different intervals (to the same or to several brain areas), or trains of repetitive stimuli at various frequencies. Single stimuli give rise to motor evoked potentials that have clinical use and serve diagnostic and prognostic purposes. Repetitive transcranial magnetic stimulation can modify excitability of cerebral cortex. Repetitive transcranial magnetic stimulation has opened a new field of investigation of the neural circuitry, and is developing into a therapeutic tool. This general review considers basic principles of transcranial magnetic stimulation, discusses methodological aspects and techniques, and analyses their utility in clinical practice.
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February 2006

[Contribution of electrophysiology to the study of a paresis of central origin].

Rev Med Suisse Romande 2003 Apr;123(4):269-71

Unité d'électroneuromyographie et des affections neuromusculaires Clinique de Neurologie Hôpitaux Universitaires de Genève 1211 Genève.

Motor evoked potentials (MEPs) to magnetic transcranial stimulation allow a functional study of the central motor pathways (from cortex to muscle). The method--noninvasive, painless and hazard-free--is readily accepted by the patients. Two main parameters are measured, namely the central motor conduction time (CMCT) and the size of the MEP. The CMCT provides information on the conduction velocity along the corticospinal pathway, it is particularly prolonged in myelin disorders. The size of MEPs correlates with the proportion of functioning motor neurons. A particular technique allows a precise quantification of conduction defects due to conduction blocks or neuronal lesions that are responsible for the paresis. Clinical applications of the method are numerous; mainly, to detect, measure and localize a dysfunction of central motor conduction of any origin. The method serves the diagnosis and on some occasions the prognosis; it allows the follow up of central motor paresis and the effect of treatments.
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April 2003
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