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PubMed1998

Pontine tegmentum hematoma. Report of a case with pure hemiplegia.

The authors report the case of a 50 year-old hypertensive male patient with a pontine hematoma. The clinical presentation was characterized by pure pyramidal deficit signs (no other signs or symptoms were present). A pure hemiplegia syndrome, although common in supratentorial lesions, is considered to be a rare event in pontine vascular lesions. The pathophysiologic mechanisms of these neurological findings are unclear. The exclusive involvement of the pyramidal tract in this case is likely due to a variation in the vascular anatomy of the pons but, in some cases, a vascular malformation may be the cause.

Cerebral Hemorrhage↗
PubMed2003

Organophosphate-induced delayed neuropathy: case report.

Organophosphate induced delayed neuropathy (OPIDN) is an uncommon clinical condition. It occurs in association with the ingestion of great amounts of organophosphate after the stimulation of cholinergic receptor. The clinical picture is characterized by a distal paresis in lower limbs associated with sensitive symptoms. Electrodiagnostic studies show a motor axonal neuropathy. Involvement of the central nervous system may occur. We describe a 39 years-old female patient who developed hyperesthesia associated with lower limbs paresis, fourteen days after she had ingested a Dichlorvos-based insecticide. Electrophysiological study was characterized by an axonal polyneuropathy pattern. Pyramidal tract dysfunction was observed later in upper limbs. Considering that both peripheral and central nervous systems are involved we believe that the more appropriated term would be organophosphate induced delayed neuropathy (OPIDN) instead of organophosphate induced delayed polyneuropathy (OPIDP).

Adult↗
PubMed2003

Pharmacological, morphological and behavioral analysis of motor impairment in experimentally vitamin C deficient guinea pigs.

The scurvy shows an inflammatory disease and gingival bleeding. Nevertheless, in an animal model for guinea pigs, described by Den Hartog Jager in 1985, scurvy was associated with a motor neuron disease with demyelinization of the pyramidal tract, provoking neurogenic atrophy of muscles. Aiming at searching the protective role of vitamin C in nervous system, a pharmacological, morphological and behavioral study was conducted. Three experimental groups were used: A100, animals receiving 100 mg/ vitamin C/ day; A5.0, animals receiving 5.0 mg/vitamin C/ day; and A0, animals without vitamin C. We analyzed the weight gain, muscular diameter and behavioral tests. In all tests examined, we found significant differences between the supplemented groups in comparison with scorbutic group (p<0.05). Thereafter, the animals were killed for histopathology of gastrocnemius muscle, spinal cord and tooth tissues. In addition, a morphometric study of periodontal thickness and alpha-motor neuron cell body diameter were done. The vitamin C-diet free regimen seemed to induce a disruption in spinal cord morphology, involving the lower motor neuron, as confirmed by a significant reduction in neuron perycaria diameter and muscular atrophy, complicated by increased nutritional deficit.

Animals↗
PubMed1983

Effect of passive movements on reaction time of the rectus femoris in normal subjects and patients with paraparesis.

Electromyographic reaction times (EMG-RTs) of the right knee extension were examined in eight normal subjects and eight patients with paraparesis under three conditions; during passive knee flexion (PFLX), passive extension (PEXT) and no passive movements (STAT). EMG-RTs of the three conditions were not significantly different between the normal and the patient group. A two-way analysis of variance (condition x group) showed that the main effect of condition was significant, but that of group and the interaction were not. Both in the normal and the patient group the shortest EMG-RTs of all was obtained in PEXT, followed by that of STAT and PFLX. Effect of passive movements on EMG-RTs in the patients whose position sense of the knee and muscle strength of the knee extension were within normal range did not vary with the abnormality of tactile sense and/or myotatic reflexes. The results indicated that activities of the pyramidal tract neurons in carrying out a movement were directly influenced by kinesthetic information of the moving limb.

Adult↗
PubMed1994

Clinico-radiological findings of neuro-Behçet's syndrome.

We examined 21 cases of Neuro-Behçet's syndrome in detail, and present here their clinicoradiological characteristics. Clinically, signs of pyramidal tract and meningeal irritation were frequently observed. In contrast to previous reports, our study demonstrated a near equal frequency in the occurrence of focal cerebral lesions and that of focal brain stem lesions. Notably, our results showed that the atrophy of both the cerebrum and the brain stem was often observed, indicating the presence of continuous disease activity in the central nervous system (CNS). In accordance with the high frequency of meningeal irritation signs, all of our cases exhibited pleocytosis in the cerebrospinal fluid (CSF). These results indicated the possibility that chemical mediators secreted from infiltrating cells in the CSF may somehow inflict damage to the CNS in Neuro-Behçet's syndrome.

Adult↗
PubMed1998

Isolated partial growth hormone deficient short stature with syringomyelia not associated with birth injury.

A 59-year-old female with 20-year history of slowly progressing muscle atrophy and sensory disturbance of upper extremities showed short stature, scoliosis, hunger type of sensory dissociation of the upper extremities and pyramidal tract sign of the lower extremities. Magnetic resonance imaging (MRI) clarified hypoplasia of the anterior pituitary lobe, Arnold-Chiari malformation and cervical syringomyelia. Insulin and arginine stimulating tests revealed partial type of isolated growth hormone (GH) deficiency but GH gene analysis detected no defects of GH genes. It was considered to be a rare case of non-hereditary hypopituitarism with Chiari malformation and syringomyelia not associated with perinatal injury, namely a midline anomaly syndrome.

Arnold-Chiari Malformation↗
PubMed2006

Subacute combined degeneration of the spinal cord concomitant with gastric cancer.

We report a rare case of subacute combined degeneration of the spinal cord concomitant with gastric cancer. A 67-year-old man was admitted because of posterior column symptoms, pyramidal tract sign and peripheral neuropathy with severe hyperchromic anemia. He was treated with mecobalamin 1 mg IM, after which his anemia and neurological signs recovered. He was diagnosed as having subacute combined degeneration with pernicious anemia. Subsequent stomach biopsy revealed gastric cancer, and the patient underwent gastrectomy. It is a well known association that chronic atrophic gastritis is associated with gastric cancer or subacute combined degeneration. Our findings suggest that in this case subacute combined degeneration and gastric cancer are independent of each other; rather, both resulted from chronic atrophic gastritis.

Aged↗
PubMed1985

Vertical spread of neuronal activity within the cat motor cortex investigated with epicortical stimulation and intracellular recording.

In the encéphale isolé cat preparation the surface of precruciate cortex was electrically stimulated. Intracellular responses underneath the stimulated site were recorded to assess the vertical spread of activities across the cortical layers. To the epicortical stimulation (EPICS) with intensity adjusted to evoke a pure negative wave in the direct cortical response (DCR), only some neurons in relatively superficial layers responded with excitatory postsynaptic potentials (EPSPs). Stimuli intensified to evoke both the negative and subsequent positive waves in DCR produced in all tested cells either EPSPs, inhibitory postsynaptic potentials (IPSPs), or both. Direct or axonal antidromic excitation of the cell was observed only infrequently. Cells with EPSPs distributed through all the layers with two peak populations in laminae II and V-VI. Those with IPSPs were located mainly in the upper half of lamina III with a few in more superficial as well as in deeper layers. Both EPSPs and IPSPs showed mono- or oligosynaptic latencies (0.6-10 msec) that tended to become longer in deep than in superficial layers. Some deep layer cells including fast and slow pyramidal tract cells showed slowly rising monosynaptic EPSPs of dendritic origin. Further late responses consisted of EPSPs, IPSPs, disfacilitation (DF), and disinhibition (DI). DF or DI occurred in some deep layer cells. Two modes of vertical spread of activities were postulated: one the cascade transmissions which increased response repertoire toward the depths, and the other the electrotonic spread of EPSPs along dendrites.

Animals↗
PubMed1994

Germinoma of the medulla oblongata--case report.

A 32-year-old female presented with medulla oblongata germinoma manifesting as numbness in the extremities. Computed tomography demonstrated a mass in the medulla oblongata expanding into the fourth ventricle. The tumor was partially removed. Immunohistochemical staining of the tumor specimen demonstrated large epithelioid cells positive for placental alkaline phosphatase, and syncytiotrophoblastic cells positive for beta subunit of human chorionic gonadotropin. Some epithelioid cells were also positive for cytokeratin. She received 44 Gy of irradiation to the posterior fossa and 20 Gy whole spinal irradiation. No signs of recurrence have occurred for 9 years. Patients with medulla oblongata germ cell tumor are comparatively older than those with other intracranial germ cell tumors and have two X chromosomes. All tumors were diagnosed as germinoma, and caused symptoms of involvement of the lower cranial nerves and the lower brain stem without pyramidal tract signs.

Adult↗
PubMed1995

Resection of deep-seated gliomas using neuroimaging for stereotactic placement of guidance catheters.

A simple computed tomography- (CT) or magnetic resonance (MR) imaging-guided stereotactic method for guided microsurgical resection of either deep-seated gliomas or tumors adjacent to an eloquent area is described. The technique employs the Brown-Roberts-Wells stereotactic system and twist drills, 2.7 mm in diameter, for the stereotactic placement of 2.4 mm diameter scaled guidance catheters through the calvaria. In a patient with a deep-seated small glioma, less than 2 cm diameter, one catheter was implanted into the center of the enhanced mass through the cerebral cortex. In the other 14 patients, three to six catheters were used which made the tumor border clearer. After implantation of the guidance catheters, the stereotactic frame was removed and a standard open craniotomy performed. Target localization is not affected by brain movement, which is inevitable during open surgery. The tumor involved the frontal lobe in eight patients, the parietal lobe in two, and the thalamus in five. In all cases the lesion was quickly localized and radical removal was achieved. Neurological complications occurred in only one patient who suffered transient hemiparesis after the resection of a lesion in the pyramidal tract. The results demonstrate that microsurgery combined with CT- or MR imaging-guided stereotactic placement of guidance catheters is a new option for surgery of deep-seated gliomas or tumors adjacent to an eloquent area.

Adult↗
PubMed1999

Diffusion-weighted echo planar imaging of acute brain infarction: a preliminary report.

The clinical usefulness of diffusion-weighted echo planar imaging (DW-EPI) was studied in 55 patients with acute brain ischemia. Ischemic lesions were identified on DW-EPI as hyperintense regions in all patients before changes were detected by conventional magnetic resonance imaging techniques in 12 cases studied earlier than 6 hours after onset. The earliest case was verified on DW-EPI at 50 minutes after onset. The ultra-fast imaging technique took less than 2 minutes to perform even for restless patients. Three patients had cardioembolic middle cerebral artery occlusion, and emergent percutaneous transluminal recanalization was carried out. Chronological changes in the signal of brain ischemia on DW-EPI depended on the site and size of the lesion, lacunar infarct of basal ganglia, and/or massive infarct due to major vessel occlusion, and were affected by associated hemorrhagic events. Coronal DW-EPI could more easily demarcate ischemia in the brainstem and/or cerebellum than axial scans when susceptibility artifacts were present. Coronal scans also demonstrated the site and direction of the pyramidal tract and its anatomical correlation with the lesions. DW-EPI has potential for the diagnostic and therapeutic planning of patients with acute brain ischemia.

Aged↗
PubMed2005

Biopsy of brain stem glioma using motor-evoked potential mapping by direct peduncular stimulation and individual adjuvant therapy. Case report.

A 23-year-old man presented with a brain stem glioma manifesting as a 6-month history of right hemiparesis and diplopia. Serial magnetic resonance imaging showed an intrinsic diffuse brain stem glioma that gradually localized to the left cerebral peduncle after initial adjuvant therapy. Surgery was performed through a left subtemporal transtentorial approach under motor-evoked potential (MEP) mapping by direct peduncular stimulation. The lateral aspect of the midbrain was exposed, a train of five bipolar 25 mA pulses was applied, and MEPs recorded from the extremities. MEPs were only recorded from the left extremities even with left cerebral peduncular stimulation. Partial resection of the tumor was safely performed, with slight temporary neurological worsening. The histological diagnosis was anaplastic astrocytoma. Individual adjuvant therapy based on the results of real-time reverse transcription-polymerase chain reaction of O6-methylguanine-deoxyribonucleic acid methyltransferase achieved an almost complete tumor response. Surgery under pyramidal tract mapping and intensive postoperative adjuvant therapy resulted in a good outcome despite the presence of a generally intractable intrinsic brain stem glioma.

Adult↗
PubMedDate not supplied

[Multiple sclerosis and fatigue].

Fatigue is a frequent symptom in multiple sclerosis, known since the first descriptions of the disease, and it has been the object of special interest in recent years due to the great influence it has on the quality of life of those suffering from the disease. The fatigue of multiple sclerosis has clinical characteristics that differentiate it from the fatigue of other systemic diseases. At the same time, it is highly variable between patients and a clear distinction can be made between three types: astenia, fatigability and the worsening of symptoms with exercise. The physiopathological bases are not fully established, but there is data indicating that astenia is related to immunoactivation and evidence of the relation of fatigability to alterations of the pyramidal tract. Another point of interest in the study of fatigue is how to objectivise and quantify it, as well as the neurophysiological techniques for its evaluation and the measurement scales most frequently employed. The paper also sets out the principal therapeutic tests and considers the relative efficacy of aminopyridine and amantadine in alleviating it.

English Abstract↗
PubMed2005

Intelligent operating theater using intraoperative open-MRI.

Malignant brain tumors vary among patients and are characterized by their irregular shapes and infiltration. Localization of functional areas in the brain also differs among patients, and excess removal of tumor near eloquent areas may increase the risk of damage of function, such as motor paresis and speech disturbance. Recent progress in magnetic resonance (MR) imaging technology has enabled acquisition of intraoperative images and totally changed the neurosurgery of malignant brain tumors. Before, surgeons could merely speculate about the results of surgical manipulation and have no certainty about procedure outcomes until postoperative examination. Because intraoperative MR images allow visualization of the size of residual tumor(s) and the positional relationship between the tumor(s) and eloquent areas, surgeons are now able to achieve safe and reliable surgery. As an example, positional error on preoperative MR images caused by shifting of the brain (brain shift), a long-standing annoyance for surgeons, has been resolved using intraoperative MR images for surgical navigation, allowing precise resection. Two types of open-MR imaging scanner, a 0.2- or 0.3-tesla hamburger-type scanner with a horizontal gap and a 0.12- or 0.5-tesla double doughnut-type scanner with a vertical gap, are now available in the operating theater, and 1.5-tesla bore-type scanners are available. A 3.0-tesla bore-type scanner is planned. Intraoperative MR imaging includes diffusion-tensor and diffusion-weighted imaging, which allows visualization of nerve fibers in the white matter, especially the pyramidal tract. Such images are valuable aids in the precise resection of residual lesions of malignant brain tumors near eloquent areas without injuring motor function.

Brain Neoplasms↗
PubMed1991

Three-dimensional trajectory analysis of congenital mirror movements in a single subject.

Mirror movements are involuntary movements executed by one side of the body that occur with voluntary activation of homologous muscles of the other side. Although such movements have been described qualitatively and with surface EMG recordings, the spatial and temporal characteristics of these movements remain relatively unexplored. We studied selected simple and complex upper limb movements in a 20-yr.-old woman with congenital mirror movements and no other neurological disorder. Movements were digitized in three-dimensional space, reconstructed computergraphically, and analyzed numerically and graphically. Mirror movements had smaller amplitudes than did the corresponding voluntary movements, and there was, in general, temporal coupling between mirror and voluntary movements. Nonetheless, mirror movements were not always a perfect mirror image of the corresponding voluntary movements and sometimes differed in timing and trajectory shape from the original movement. Substantially larger mirror movements were elicited by distal than by proximal movements, and mirror movements were enhanced when loads were applied to the hand executing the voluntary movement. These data support the proposal that congenital mirror movements are produced by a partial failure of decussation of the pyramidal tract. We suggest that the variability in the extent to which mirror movements correspond to the voluntary movements is due to propriospinal and descending extrapyramidal input.

Adult↗
PubMed1996

Treatment with electromagnetic field alters the clinical course of chronic progressive multiple sclerosis--a case report.

It is estimated that 10-20% of patients with multiple sclerosis (MS) have a chronic progressive (CP) course characterized by an insidious of neurological deficits followed by steady progression of disability in the absence of symptomatic remission. No therapeutic modality has shown specific efficacy in the treatment of patients with CP MS and there are no data to indicate that any pharmacologic or other modality alters the clinical course of CP MS. Treatment with picotesla electromagnetic fields (EMFs) is a highly effective modality for the symptomatic management of MS including the chronic progressive form. In addition, this treatment also appears to alter the natural course of the disease in CP patients. A 36 year-old man experienced, at the age of 31, insidious weakness in the legs and several months later developed difficulties with balance with ataxia of gait. His gait abnormality progressed slowly over the following years and at the age of 35 he was severely disabled with spastic paraparesis and ataxia using a rolling walker for ambulation and a scooter for longer distances. In particular, his disability had progressed rapidly over the six months preceding the initiation of treatment with EMFs. He as classified have CP MS and his prognosis was considered extremely unfavorable due to the degree of cerebellar and pyramidal tract involvement and the rapid course of deterioration. In July 1995 the patient began experimental treatment with EMFs. While receiving three treatment sessions a week over 12 months he experienced improvement in cerebellar functions such as gait, balance and tremor as well as bowel and bladder functions, mood, sleep and cognitive function and resolution of diplopia, blurring of vision, dysarthria, paresthesias in the hands, and fatigue. Most remarkably, there was no further progression of the disease during the course of magnetic therapy. This case illustrated that treatment with EMFs, in addition to producing symptomatic improvement, also reverses the clinical course of CP MS.

Adult↗
PubMed1990

[Ageing and central motor conduction time].

The corticomotoneuronal pathway in the aged was studied using the technique of percutaneous electrical stimulation of the brain and the spinal cord. Central motor conduction time (CMCT) from the cerebral motor cortex to the cervical segment of the spinal cord (C-CMCT) was measured in 26 intact volunteers (20-85 years old) by substracting the latency to onset of EMG activity of the thenar muscle after cervical stimulation from the latency to onset of EMG activity of the same muscle after cortical stimulation. The latencies to onset of action potential of the anterior tibial muscle after cortical stimulation and the onset of action potential of the same muscle after lumbar stimulation were also measured in 11 volunteers (aged 46-67 years), and the difference between the two latencies was evaluated as the central motor conduction time from the cortex to the lumbar segment of the spinal cord (L-CMCT). Mean C-CMCT was 5.1 ms. and mean L-CMCT was 12.8 ms. Neither was related to the patient's height or age. There was no difference in either C-CMCT or L-CMCT between males and females. The results suggested that the conduction of the pyramidal tract is not affected by age, and this must be recognised when motor functions in the aged are studied.

Adult↗