Effects of Bihemispheric Transcranial Direct Current Stimulation Combined With Repetitive Peripheral Nerve Stimulation in Acute Stroke Patients.

PURPOSE: Transcranial direct current stimulation (tDCS) can change the excitability of the central nervous system and contribute to motor recovery of stroke patients. The aim of our study was to examine the short- and long-term effects of real versus sham bihemispheric tDCS combined with repetitive peripheral nerve stimulation in patients with acute stroke and a severe motor impairment. METHODS: The study was prospective, randomized, double blind, and placebo controlled. Nineteen acute stroke patients (ischemic and hemorrhagic) with upper limb Fugl-Meyer mean score of <19 were randomized in two groups: one group received five consecutive daily sessions of anodal tDCS over the affected hemisphere and cathodal over unaffected hemisphere combined with repetitive peripheral nerve stimulation and the other received sham tDCS associated to repetitive peripheral nerve stimulation. Clinical and neurophysiological assessment was applied before tDCS, 5 days after tDCS, and 3, 6, and 12 months after tDCS. RESULTS: There were significant time-related changes in both groups of patients in motor evoked potentials, somatosensory evoked potentials, Hmax:Mmax ratio, upper limb Fugl-Meyer scores, and Modified Ashworth scales scores ( P < 0.05). However, no significant differences between groups were present at any time ( P > 0.05). CONCLUSIONS: Bihemispheric tDCS and repetitive peripheral nerve stimulation with the parameters of our study did not add significant short- or long-term clinical improvement or change in neurophysiological data in severe acute stroke patients in comparison to sham stimulation. The severity of motor impairment in stroke patients may influence a possible response to an interventional tDCS treatment.

Neuralgia del nervio pudendo posparto / Pudendal nerve entrapment syndrome after delivery

Describimos 2 casos clínicos de dolor neuropático en la región perineal tras un parto vaginal. Después del examen físico y las pruebas de imagen, ambos casos se diagnosticaron de síndrome de atrapamiento del nervio pudendo. El primer caso se resolvió tras el desbridamiento de un hematoma en el canal de Alcock. El segundo caso se resolvió mediante fisioterapia. Es importante conocer el síndrome para ofrecer un tratamiento lo menos invasivo posible (AU)

We describe two patients with post-vaginal birth neuropathic-type pain in the perineal region. Pudendal nerve entrapment syndrome was diagnosed on the basis of a physical examination and imaging tests. The first case was resolved by debridement of a hematoma in Alcock's canal. The second case was resolved by physical therapy. Familiarity with this syndrome is important to be able to offer the least invasive treatment possible (AU)

Plasticity in the sensorimotor cortex induced by Music-supported therapy in stroke patients: a TMS study.

Playing a musical instrument demands the engagement of different neural systems. Recent studies about the musician's brain and musical training highlight that this activity requires the close interaction between motor and somatosensory systems. Moreover, neuroplastic changes have been reported in motor-related areas after short and long-term musical training. Because of its capacity to promote neuroplastic changes, music has been used in the context of stroke neurorehabilitation. The majority of patients suffering from a stroke have motor impairments, preventing them to live independently. Thus, there is an increasing demand for effective restorative interventions for neurological deficits. Music-supported Therapy (MST) has been recently developed to restore motor deficits. We report data of a selected sample of stroke patients who have been enrolled in a MST program (1 month intense music learning). Prior to and after the therapy, patients were evaluated with different behavioral motor tests. Transcranial Magnetic Stimulation (TMS) was applied to evaluate changes in the sensorimotor representations underlying the motor gains observed. Several parameters of excitability of the motor cortex were assessed as well as the cortical somatotopic representation of a muscle in the affected hand. Our results revealed that participants obtained significant motor improvements in the paretic hand and those changes were accompanied by changes in the excitability of the motor cortex. Thus, MST leads to neuroplastic changes in the motor cortex of stroke patients which may explain its efficacy.

Sensorimotor plasticity after music-supported therapy in chronic stroke patients revealed by transcranial magnetic stimulation.

BACKGROUND: Several recently developed therapies targeting motor disabilities in stroke sufferers have shown to be more effective than standard neurorehabilitation approaches. In this context, several basic studies demonstrated that music training produces rapid neuroplastic changes in motor-related brain areas. Music-supported therapy has been recently developed as a new motor rehabilitation intervention. METHODS AND RESULTS: In order to explore the plasticity effects of music-supported therapy, this therapeutic intervention was applied to twenty chronic stroke patients. Before and after the music-supported therapy, transcranial magnetic stimulation was applied for the assessment of excitability changes in the motor cortex and a 3D movement analyzer was used for the assessment of motor performance parameters such as velocity, acceleration and smoothness in a set of diadochokinetic movement tasks. Our results suggest that the music-supported therapy produces changes in cortical plasticity leading the improvement of the subjects' motor performance. CONCLUSION: Our findings represent the first evidence of the neurophysiological changes induced by this therapy in chronic stroke patients, and their link with the amelioration of motor performance. Further studies are needed to confirm our observations.

Immunogenicity and safety of a live attenuated shingles (herpes zoster) vaccine (Zostavax®) in individuals aged ≥ 70 years: a randomized study of a single dose vs. two different two-dose schedules.

Disease protection provided by herpes zoster (HZ) vaccination tends to reduce as age increases. This study was designed to ascertain whether a second dose of the HZ vaccine, Zostavax(®), would increase varicella zoster virus (VZV)-specific immune response among individuals aged ≥ 70 y. Individuals aged ≥ 70 y were randomized to receive HZ vaccine in one of three schedules: a single dose (0.65 mL), two doses at 0 and 1 mo, or two doses at 0 and 3 mo. VZV antibody titers were measured at baseline, 4 weeks after each vaccine dose, and 12 mo after the last dose. In total, 759 participants (mean age 76.1 y) were randomized to receive vaccination. Antibody responses were similar after a single dose or two doses of HZ vaccine [post-dose 2/post-dose 1 geometric mean titer (GMT) ratios for the 1-mo or 3-mo schedules were 1.11, 95% confidence interval (CI) 1.02-1.22 and 0.78, 95% CI 0.73-0.85], respectively). The 12-mo post-dose 2/12-mo post-dose 1 GMT ratio was similar for the 1-mo schedule and for the 3-mo schedule (1.06, 95% CI 0.96-1.17 and 1.08, 95% CI 0.98-1.19, respectively). Similar immune responses were observed in participants aged 70-79 y and those aged ≥ 80 y. HZ vaccine was generally well tolerated, with no evidence of increased adverse event incidence after the second dose with either schedule. Compared with a single-dose regimen, two-dose vaccination did not increase VZV antibody responses among individuals aged ≥ 70 y. Antibody persistence after 12 mo was similar with all three schedules.

Unusual forehead tremor in four patients with essential tremor.

Forehead tremor has only been reported in two patients with essential tremor, one with rhythmic tremor and the other with dystonic tremor. We report 4 new patients with essential tremor who present a 4-6 Hz frontal tremor registered by electromyography and unusual features like frontal tremor preceding limb tremor or unilateral involvement. Frontal tremor is present in some patients with essential tremor, sometimes preceding limb tremor. Treatment with botulinum toxin may be useful.

Prognostic value of cortically induced motor evoked activity by TMS in chronic stroke: caveats from a revealing single clinical case.

BACKGROUND: We report the case of a chronic stroke patient (62 months after injury) showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS) of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand. CASE PRESENTATION: Multimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP), and Cortical Silent period (CSP) as well as functional magnetic resonance imaging (fMRI) of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI) Tractography of corticospinal tract (CST). Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG) activity (indexed by CSP) demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations. CONCLUSIONS: The potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.

A novel small deletion in PMP22 causes a mild hereditary neuropathy with liability to pressure palsies phenotype.

INTRODUCTION: In this study we examined a family with electrophysiological findings of hereditary neuropathy with liability to pressure palsies (HNPP) and a mild clinical presentation. METHODS: Four members of a family were referred for diagnosis of HNPP. Electrophysiological studies included motor and sensory nerve conduction studies in the upper and lower extremities. Investigations of microsatellites, using polymorphic repeat markers flanking the gene, and multiplex ligation-dependent probe amplification (MLPA) were performed for molecular studies. RESULTS: The initial study of microsatellites did not detect any change, but MLPA demonstrated a small deletion of exon 5 in the PMP22 gene. CONCLUSION: Our findings demonstrate the important role of small deletions in the PMP22 gene in the etiology of HNPP with a normal microsatellite study.

Hyperexcitability of the facial nerve in tuberculous meningitis.

INTRODUCTION: Facial myokymias (FM) are continuous, involuntary, undulating movements of the facial muscles associated with spontaneous electromyographic activity, such as fasciculations and myokymic discharges. They may occur in healthy individuals, or be secondary to multiple sclerosis, posterior fossa tumors, or an inflammatory process. PATIENT AND RESULTS: We describe the case of a 31-year-old man who presented with headache, vomiting, low fever, and disorientation. Cerebrospinal fluid findings included low glucose and high protein content and lymphocyte pleocytosis, with positive culture for Myobacterium tuberculosis. The patient was diagnosed with tuberculous meningitis. Magnetic resonance imaging showed high contrast enhancement in the basal meninges and a left frontal tuberculoma. Over the course of the disease, he experienced FM and persistent, involuntary contraction of the facial muscles. The electromyogram recorded myokymic discharges. DISCUSSION: Tuberculous meningitis is a rare cause of FM. The presence of myokymic discharges on electromyography verified the peripheral origin of facial nerve hyperexcitability in this case, in contrast to persistent contraction of the facial muscles, which has a central origin. The phenomena were transitory and only positive symptoms were observed, with no facial nerve injury. CONCLUSION: Tuberculous meningitis is a rare cause of facial nerve hyperexcitability, which can have a peripheral, nuclear, or supranuclear origin.

Very early electrodiagnostic findings in Guillain-Barré syndrome.

Electrodiagnostic studies play a key role in the evaluation of patients with Guillain-Barré syndrome (GBS). However, at early stages patients may not meet current neurophysiologic criteria. We report electrodiagnostic findings for 18 patients with suspected GBS within 4 days of clinical onset. Fifteen patients (83%) showed abnormality in the motor nerve conduction study. Prolonged distal motor latency (DML) was the most frequent demyelinating parameter (seen in 55% of patients). Abnormal late responses were noted in 14 patients (77%). Electrodiagnostic study of cranial nerves was abnormal in eight (44%), and motor nerve conduction velocity was abnormal in only six patients (23%). The study shows a predominant motor neuropathy pattern followed by a sural-sparing pattern; no patients showed a strictly normal electrodiagnostic study. Reduced distal compound muscle action potential and prolonged DML in the demyelinating range were associated with severity of GBS on admission. After the electrodiagnostic study, 5 patients (27%) already fulfilled electrodiagnostic criteria for acute inflammatory demyelinating polyneuropathy (AIDP), 1 (5%) for the axonal variant of GBS, and 13 (72%) were classified as equivocal. We conclude that exhaustive electrodiagnostic studies of patients with suspected GBS in very early stages are useful in the diagnosis and management of the condition.

Music-supported therapy induces plasticity in the sensorimotor cortex in chronic stroke: a single-case study using multimodal imaging (fMRI-TMS).

PRIMARY OBJECTIVE: Music-Supported Therapy (MST) has been developed recently in order to improve the use of the affected upper extremity after stroke. This study investigated the neuroplastic mechanisms underlying effectiveness in a patient with chronic stroke. METHODS: MST uses musical instruments, a midi piano and an electronic drum set emitting piano sounds, to retrain fine and gross movements of the paretic upper extremity. Data are presented from a patient with a chronic stroke (20 months post-stroke) with residual right-sided hemiparesis who took part in 20 MST sessions over the course of 4 weeks. RESULTS: Post-therapy, a marked improvement of movement quality, assessed by 3D movement analysis, was observed. Moreover, functional magnetic resonance imaging (fMRI) of a sequential hand movement revealed distinct therapy-related changes in the form of a reduction of excess contralateral and ipsilateral activations. This was accompanied by changes in cortical excitability evidenced by transcranial magnetic stimulation (TMS). Functional MRI in a music listening task suggests that one of the effects of MST is the task-dependent coupling of auditory and motor cortical areas. CONCLUSIONS: The MST appears to be a useful neurorehabilitation tool in patients with chronic stroke and leads to neural reorganization in the sensorimotor cortex.

Charcot-Marie-Tooth disease with intermediate conduction velocities caused by a novel mutation in the MPZ gene.

Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of inherited sensory and motor neuropathies. Mutations in the gene that encodes for myelin protein zero (MPZ) can produce different phenotypes: CMT1 (with low conduction velocities), CMT2 (less frequent and with unaffected conduction velocities), and CMTID (with intermediate conduction velocities). We report a study of seven patients from a four-generation family. All the affected members of the family had a typical CMT phenotype, but three of them had calf hypertrophy. The nerve conduction velocities (NCV) in all of them were between 35 and 43 m/s. Molecular study revealed the novel mutation Lys214Met in the MPZ gene. Molecular study of the MPZ gene would be useful in cases of CMT in families with intermediate NCV, especially if no mutations in the GJB-1 gene are found or there is male-to-male transmission.

Diagnosis of Charcot-Marie-Tooth disease.

Charcot-Marie-Tooth (CMT) disease or hereditary motor and sensory neuropathy (HMSN) is a genetically heterogeneous group of conditions that affect the peripheral nervous system. The disease is characterized by degeneration or abnormal development of peripheral nerves and exhibits a range of patterns of genetic transmission. In the majority of cases, CMT first appears in infancy, and its manifestations include clumsiness of gait, predominantly distal muscular atrophy of the limbs, and deformity of the feet in the form of foot drop. It can be classified according to the pattern of transmission (autosomal dominant, autosomal recessive, or X linked), according to electrophysiological findings (demyelinating or axonal), or according to the causative mutant gene. The classification of CMT is complex and undergoes constant revision as new genes and mutations are discovered. In this paper, we review the most efficient diagnostic algorithms for the molecular diagnosis of CMT, which are based on clinical and electrophysiological data.

Exploración neurológica y neurofisiológica del suelo pelviano / Neurological and neurophysiological exploration of the pelvic floor

Las alteraciones funcionales de la micción y de la defecación son muy frecuentes en la población general y mucho más entre los pacientes neurológicos. Conocer la fisiopatología de estos trastornos es esencial en la práctica clínica. El control neurológico de estas funciones se realiza a partir de automatismos regulados en los núcleos del tronco cerebral mediante estructuras periféricas somáticas y vegetativas que actúan simultáneamente. La continencia depende de la integridad de las estructuras anatómicas y de los sistemas mecánicos, presivos y sensoriales que permiten el desarrollo de los automatismos. El examen neurológico debe insertarse en los estudios que realizan otros especialistas, especialmente la ecografía y la manometría, lo que permite valorar de forma objetiva la localización y la gravedad del daño neuromuscular. El objetivo de este estudio es triple: describir los mecanismos neurológicos que rigen la defecación y la micción; revisar los métodos clínicos y los tests electromiográficos de exploración neurológica del suelo de la pelvis, y por último, presentar nuestro protocolo de actuación exploratoria en las disfunciones del suelo pelviano (AU)

Incontinencia fecal: neurofisiología y neuromodulación / Fecal incontinence: neurophysiology and neuromodulation

La incontinencia fecal puede causar un déficit importante en la calidad de vida de los pacientes y originar sociopatías graves. Numerosos pacientes afectados de incontinencia fecal adoptan hábitos sociales y conductas que evitan las relaciones personales. Las claves diagnósticas de estos trastornos y las opciones terapéuticas, todavía en desarrollo, están escasamente sistematizadas. La neurofisiología de la defecación está todavía por aclarar y depende de la integridad de las estructuras anatómicas y neuronales, así como de la correcta coordinación de muchos sistemas mecánicos y presivos que permiten el desarrollo de este automatismo, que se aprende en los primeros años de vida. La exploración estructural del canal anal debe combinarse con un estudio neurofisiológico que nos permita ahondar en el conocimiento de estos trastornos, catalogar mejor a los pacientes e indicar diferentes alternativas terapéuticas con mayor eficacia. La aparición de la estimulación de raíces sacras, que basa su efecto terapéutico en la neuromodulación, debe implicar a los cirujanos en el conocimiento de las bases neurológicas de la defecación y las exploraciones que deberían realizarse en todos los pacientes con incontinencia fecal (AU)

Role of EMG evaluation in muscle hyperactivity syndromes.

Muscle hyperactivity can be a clinical feature on its own or, more commonly, an observation on electromyography (EMG) examinations. Whatever manifestation it takes, muscle hyperactivity always means enhanced excitability of muscle, axons or neurons. Clinical findings may be variable, ranging from fasciculations to muscle cramps. Even though clinical examination may lead in most instances to suggest the diagnosis of the underlying disease, EMG studies are necessary to identify the type of abnormal discharges and suggest the site of their suspected origin. Although in clinical studies, the action potential showing abnormal muscle hyperactivity is practically always recorded from muscle fibers, the site in which the impulse has arisen will determine its shape and firing patterns. In this review, we describe the EMG characteristics observed in syndromes featuring muscle hyperactivity and the pathophysiology underlying the abnormal firing of muscle fibers.

Movement disorders in patients with peripheral facial palsy.

Acute unilateral facial paralysis is usually a benign neurological condition that resolves in a few weeks. However, it can also be the source of a transient or long-lasting severe motor dysfunction, featuring disorders of automatic and voluntary movement. This review is organized according to the two most easily recognizable phases in the evolution of facial paralysis: (1). Just after presentation of facial palsy, patients may exhibit an increase in their spontaneous blinking rate as well as a sustained low-level contraction of the muscles of the nonparalyzed side, occasionally leading to blepharospasm-like muscle activity. This finding may be due to an increase in the excitability of facial motoneurons and brainstem interneurons mediating trigeminofacial reflexes. (2). If axonal damage has occurred, axonal regeneration beginning at approximately 3 months after the lesion leads inevitably to clinically evident or subclinical hyperactivity of the previously paralyzed hemifacial muscles. The full-blown postparalytic facial syndrome consists of synkinesis, myokymia, and unwanted hemifacial mass contractions accompanying normal facial movements. The syndrome has probably multiple pathophysiological mechanisms, including abnormal axonal branching after aberrant axonal regeneration and enhanced facial motoneuronal excitability. Although the syndrome is relieved with local injections of botulinum toxin, fear of such uncomfortable contractions may lead the patients to avoid certain facial movements, with the implications that this behavior might have on their emotional expressions.