J Montero

Hospital Universitari de Bellvitge, l'Hospitalet de Llobregat, Catalonia, Spain

Are you J Montero?

Claim your profile

Publications (32)55.51 Total impact

  • Clinical Neurophysiology. 02/2012; 123(2):e5.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Case reports in neurological medicine. 01/2012; 2012:278140.
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study we examined a family with electrophysiological findings of hereditary neuropathy with liability to pressure palsies (HNPP) and a mild clinical presentation. 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. The initial study of microsatellites did not detect any change, but MLPA demonstrated a small deletion of exon 5 in the PMP22 gene. Our findings demonstrate the important role of small deletions in the PMP22 gene in the etiology of HNPP with a normal microsatellite study.
    Muscle & Nerve 01/2012; 45(1):135-8. · 2.31 Impact Factor
  • Revue Du Rhumatisme - REV RHUM. 12/2011;
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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. 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. 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. Tuberculous meningitis is a rare cause of facial nerve hyperexcitability, which can have a peripheral, nuclear, or supranuclear origin.
    Acta neurologica Belgica 09/2011; 111(3):245-8. · 0.47 Impact Factor
  • Joint, bone, spine: revue du rhumatisme 06/2011; 78(5):536-7. · 2.25 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Journal of the Peripheral Nervous System 06/2011; 16(2):136-42. · 2.57 Impact Factor
  • Joint, bone, spine: revue du rhumatisme 05/2011; 78(4):427-8. · 2.25 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    Muscle & Nerve 08/2010; 42(2):184-8. · 2.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    BioMed Research International 01/2009; 2009:985415. · 2.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mutations in the Mitofusin 2 (MFN2) gene have been related to the axonal type of Charcot-Marie-Tooth type 2 (CMT 2A). We report the first two Spanish families with CMT 2 and mutations in MFN2 gene. Molecular studies of one family with late onset revealed the novel mutation Arg364Gln. The affected family members presented mild clinical and electrophysiological worsening after 14 years of follow-up. The other family presented an early onset and optic atrophy. Molecular studies revealed the Arg94Gln mutation. This is the first report of a family in which this mutation is related to optic atrophy. Molecular analysis aimed at detecting mutations of MFN2 could be extremely useful in mild axonal neuropathies with slow evolution and indispensable in cases of dominant inheritance or optic atrophy. Population studies of mutations in MFN2 should be undertaken to discover the real frequencies in the Mediterranean area.
    Neuromuscular Disorders 12/2008; 18(12):974-8. · 3.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Dropped head sign is characterized by the gradual forward sagging of the head due to weakness of neck extensor muscles. This may be a prominent sign of several neuromuscular disorders and may be an isolated feature of myasthenia gravis (MG). We describe a patient with isolated neck extensor weakness, eletrophysiological findings suggesting myasthenia gravis and positive MuSK antibodies. This case supports that finding anti-MuSK antibodies may be extremely helpful in dropped head patients and negative acetylcholine receptor antibodies especially if needle EMG does not reveal myopathic or neurogenic patterns.
    Neuromuscular Disorders 08/2007; 17(7):544-6. · 3.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Thermoalgesic sensory deficits in patients with syringomyelia may escape objective documentation with conventional electrophysiological techniques. We examined six patients with radiologically proven centrospinal cavities and patchy thermoalgesic sensory deficits by recording the evoked potentials and the sympathetic sudomotor skin responses (SSR) to laser stimuli. While electrical stimuli to the affected areas induced evoked potentials and SSRs of normal latency and amplitude, CO2 laser stimulation induced absent or abnormally reduced evoked potentials. Also, warmth and heat pain stimulation with a Peltier thermode induced absent or abnormal SSRs when applied over the affected areas but well defined SSRs when applied to the corresponding contralateral areas. Our results reveal the utility of recording the SSR to pain and temperature stimuli over specific body sites to demonstrate impairment of pain and temperature pathways in patients with syringomyelia. Comparison of electrical versus laser and temperature induced SSRs is an objective means to evaluate the selective thermoalgesic sensory deficit in these patients.
    Journal of Neurology 06/2007; 254(5):638-45. · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: One of the classic features of hemifacial spasm (HFS) is spread of the blink reflex responses to muscles other than the orbicularis oculi. The pathophysiological mechanisms underlying the generation of such abnormal responses include lateral spread of activity between neighboring fibers of the facial nerve and hyperexcitability of facial motoneurons. In this report we present evidence for another mechanism that can contribute to the generation of responses in lower facial muscles resembling the R1 response of the blink reflex. In 13 HFS patients, we studied the responses induced in orbicularis oris by electrical stimuli applied at various sites between the supraorbital and zygomatic areas. We identified responses with two different components: an early and very stable component, with an onset latency ranging from 10.5 to 14.8 ms, and a more irregular longer-latency component. Displacement of the stimulation site away from the supraorbital nerve and towards the extracranial origin of the facial nerve caused a progressive shortening of response latency. These features indicate that, in our patients, the shortest latency component of the orbicularis oris response was likely generated by antidromic conduction in facial nerve motor axons followed by axono-axonal activation of the fibers innervating the lower facial muscles. Our results suggest that motor axono-axonal responses are generated by stimulation of facial nerve terminals in HFS.
    Muscle & Nerve 03/2007; 35(2):184-8. · 2.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We performed single-fiber electromyography by axonal stimulation (stimulated SFEMG) of the frontalis and orbicularis oculi muscles of 20 patients with ocular myasthenia gravis (OM) and 46 controls. In controls, mean consecutive differences (MCD) ranged from 5 to 55 micros (average, 14.7 +/- 2.8 micros) in the frontalis and from 4 to 56 micros (average, 12.56 +/- 2.19 micros) in orbicularis oculi. The mean MCD of individual muscle potentials (MPs) was 14.6 +/- 6.8 micros in frontalis and 12.68 +/- 6.10 micros in orbicularis oculi. In the OM patients, the mean MCD was 43.85 +/- 25.18 micros in the frontalis and 69.85 +/- 29.55 micros in orbicularis oculi (P < 0.0001), and the number of MPs with altered MCD was 7.15 +/- 4.66 (range, 1-18) and 12.65 +/- 4.90 (range, 6-21), respectively (P < 0.0001). We conclude that stimulated SFEMG of the orbicularis oculi muscle is more sensitive for the diagnosis of OM than of the frontalis muscle.
    Muscle & Nerve 11/2003; 28(4):501-3. · 2.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Diabetic polyneuropathy is the most common subgroup of diabetic neuropathy, but its nature is controversial as it might be demyelinating and/or axonal. We have tried to determine whether diabetic polyneuropathy is electrophysiologically axonal, demyelinating, or both. We have studied the sural and peroneal nerves and the electromyographies of leg muscles in 50 healthy subjects (average age 67.2 years, range 45 to 84 years), in 50 diabetic patients (average age 66.34 years, range 44 to 82 years) showing no symptoms and/or signs of polyneuropathy (DP1), and in 50 diabetic patients (average age 67.10 years, range 49 to 87 years) showing symptoms and/or signs of polyneuropathy (DP2). The amplitude (AMP) of sural and peroneal nerves in healthy and DP1 subjects was similar. Conduction velocity (CV) of sural and peroneal nerves was slower in DP1 subjects than in healthy subjects. DP2 subjects showed AMP and CV values significantly lower than those in DP1 subjects, and signs of acute and chronic denervation/reinervation were found in the leg muscles. We believe that this result indicates that diabetic patients have two types of polyneuropathies: a demyelinating disease that could appear in diabetic patients with and without symptoms of polyneuropathy, and an axonal loss that is responsible for most of the symptoms.
    Electromyography and clinical neurophysiology 01/2002; 42(1):3-6.
  • J Valls-Canals, J Montero, J Pradas
    [Show abstract] [Hide abstract]
    ABSTRACT: We performed single fiber electromyography by axonal stimulation (SFEMG-AS) of the frontalis muscle of 16 patients with ocular myasthenia gravis (OM) and 33 controls. In the controls, values of mean consecutive differences (MCD) ranged from 5 to 55 micros (average, 14.7 +/- 2.8 micros) and mean MCD of individual MPs was 14. 6 +/- 6.8 micros. All the OM patients showed abnormal SFEMG-AS jitter before prostigmine was administered (mean MCD: 49.19 +/- 21. 82 micros, percentage of blocks: 20.97 +/- 18.53). Twenty or 30 min after prostigmine had been administered, we saw a significant improvement in jitter: mean MCD was 36.38 +/- 22.49 micros (P = 0. 005), and percentage of blocks was 10.16 +/- 18.87 (P = 0.008). The method was well tolerated. We conclude that SFEMG-AS of the frontalis muscle is a sensitive technique for the diagnosis of OM and is easy to carry out.
    Muscle & Nerve 06/2000; 23(5):779-83. · 2.31 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In order to establish the focal compression in the elbow, a study of 318 patients with clinical manifestations of ulnar neuropathy was carried out. We divided the patients in three groups: I) those who presented mechanical anomalies with background of fracture, elbow valgus...; II) those who did not present mechanical anomalies, but they have been in bed long time or they have been operated...; III) those who did not have evident cause for the compression. Antidromic sensory conduction and segmentary motor conduction of the ulnar nerve were studied, and segmental motor conduction along the elbow with interval of 2 centimetres (technique of Kanakamedala). 83.6% of the 318 ulnar neuropathy had the focal compression in the ulnar sulcus. 8.2% had the focal compression distal to the ulnar sulcus. 0.94% had double focal compression. In 7.2% was not possible to determinate the focal compression. In group I, the focal compression was in the ulnar sulcus in 93.8% of the cases. In group II, the focal compression was in the ulnar sulcus in 94.3% of the cases. In group III, the focal compression was in the ulnar sulcus in 55.8% of the cases, and distal to the ulnar sulcus in 29.1% of the cases. It is possible to localize the focal compression of the ulnar neuropathy in the elbow, with high level of probability, with the nerve conductions. This allows the surgeon to be orientated about therapeutical attitude.
    Neurologia (Barcelona, Spain) 10/1999; 14(8):389-92. · 1.32 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chronic inhalation of glues containing n-hexanes produces neurofilament (NF) accumulation which induces sensory-motor polyneuropathy. In vitro assays have shown this toxic substance causes intermediate filaments (IF) aggregation in non-neuronal cells. To describe intermediate filament changes in human pathology due to n-hexanes. Sural nerve and skin biopsy samples from 2 patients who suffered from a severe sensory-motor polyneuropathy after prolonged inhalation of glue containing n-hexane were examined with electron microscopy and vimentin and phosphorylated NF immunocytochemistry. Abnormal accumulations of NF and NF-immunoreactive products occurred in nerve fibers and increased numbers of fibrils were observed in endoneurial endothelial cells of the sural nerve. In addition, abnormal vimentin-immunoreactive deposition was seen in fibroblasts and capillaries of the skin. The present results suggest that high doses of n-hexane cause a diffuse IF disorder in a similar form as occurs in giant axonal neuropathy. IF aggregation can occur in non-neuronal cells in humans, as has been previously proved in in vitro experiments. The presence of IF accumulations in Schwann cells, as seen in the ultrastructural examination, together with the electrophysiological findings showing an early decrease of sensory and motor nerve conduction velocities, suggests the existence of a primary myelinic disorder associated with axonal damage.
    Neurologia (Barcelona, Spain) 12/1998; 13(9):417-21. · 1.32 Impact Factor
  • J Valls Canals, J Montero, J Pradas
    [Show abstract] [Hide abstract]
    ABSTRACT: A neurophysiological study of 921 hands with clinical manifestations of carpal tunnel syndrome (CTS), 88 of normal individuals and 588 of patients with disorders not related with median neuropathy was carried out to establish the diagnostic sensibility 130 non-operated on patients with slight CTS were controlled one year later. The same was achieved with 105 surgically treated patients in order to establish the electrophysiological changes related to therapeutic methods. Antidromic sensory conduction and segmentary motor conduction of the median nerve were studied along with the difference between median and ulnar sensory latencies. Only 84 of the 921 hands (5.2%) showed normal electrophysiological findings and 469 (50.9%) minimal changes. 343 hands (37.2%) showed signs suggestive of axonal degeneration in sensory fibers and 147 (16%) in motor ones. Of the 130 slight CTS not surgically treated, clinical manifestations persisted for one year in 118, 17 of which have normal electrophysiological parameters. Twenty six (20%) of these 130 hands got worse. Of the 105 CTS surgically treated hands, 58 continued with symptoms one year later in spite of the electrophysiological improvement in 88.6% of them. Among 588 patients hands without CTS symptoms, only 0.8% had electrophysiological signs suggesting CTS. A high yield of the electrophysiological diagnosis of the CTS is shown. Symptoms frequently persist in patients without definite nerve compression.
    Neurologia (Barcelona, Spain) 03/1998; 13(2):69-73. · 1.32 Impact Factor