Craniocervical decompression with duraplasty and cerebellar tonsillectomy as treatment for Chiari malformation-I complicated with syringomyelia.

This study aimed to investigate the therapeutic effects of craniocervical decompression with duraplasty and cerebellar tonsillectomy for the treatment of Chiari malformation-I with syringomyelia (CM I-SM). From January 2005 to December 2011, 127 patients with CM I-SM underwent craniocervical decompression with duraplasty and cerebellar tonsillectomy and the therapeutic effects of these surgeries were evaluated using Tator scores. No patient in this study died or showed disease deterioration after the surgery. Re-examination by magnetic resonance imaging (MRI) showed that the cisterna magna was obviously larger after the operation in all but one patient. Moreover, syringomyelia (SM) was reduced in 76 patients. CM I-SM symptoms disappeared or decreased in 112 patients after following discharge. Follow-up was conducted in 84 of the patients and 79 of these patients exhibited improved symptoms. A second MRI re-examination showed that the cisterna magna was successfully constructed in 44 patients; 42 of these patients showed further eliminated or obviously reduced SM. Craniocervical decompression with duraplasty and cerebellar tonsillectomy achieved favorable therapeutic effects. Thus, craniocervical decompression with duraplasty and cerebellar tonsillectomy is a rational surgical approach with beneficial clinical effects. The proposed approach may have useful applications in the treatment of CM I-SM.

Pseudoathetosis: report of three patients.

We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.

International survey on the management of Chiari I malformation and syringomyelia.

INTRODUCTION: The availability of magnetic resonance imaging (MRI) has resulted in an increasing number of asymptomatic, minimally symptomatic, and doubtfully symptomatic patients being diagnosed with a Chiari I malformation with or without syringomyelia. In an attempt to clarify how neurosurgeons manage these clinical problems, an international survey on the Chiari I malformation and related syringomyelia was undertaken. METHOD: A questionnaire on the expected natural course of the disease and on aspects of the surgical technique for a number of hypothetical cases relating to Chiari I malformation with and without syringomyelia was used to survey Pediatric Neurosurgeons worldwide. RESULTS: Of 246 questionnaires distributed, 76 (30.8%) were completed and returned. There was a consensus that no operation should be carried out in asymptomatic patients with a Chiari I malformation, unless there is associated syringomyelia. There was a consensus that decompression of the Chiari malformation should be performed in patients with scoliosis when syringomyelia is present, and the majority decompressed the Chiari malformation in scoliotic patients even in the absence of syringomyelia. Suboccipital decompression was the standard surgical procedure for Chiari I malformations. The majority of respondents favored routine dural opening at surgery and closure with a pericranial or synthetic patch graft. In the case of a persistent or progressive syrinx after suboccipital decompression, the majority recommended shunting of the syrinx to the subarachnoid space or to the pleural cavity. CONCLUSION: There continues to be much variation in the management of the Chiari I malformation.

Postural tachycardia syndrome in syringomyelia: response to fludrocortisone and beta-blockers.

Orthostatic intolerance is occasionally reported by patients with syringomyelia and is usually attributed to vestibular symptoms or neurogenic orthostatic hypotension. Postural tachycardia syndrome has not been previously described in syringomyelia. A patient with long-standing syringomyelia and a Chiari type I anomaly developed disabling "panic-like" attacks associated to orthostatic intolerance five years after posterior fossa decompression and shunting of the syrinx. A head-up tilt test showed an early phase of postural orthostatic tachycardia followed by progressive arterial hypotension and bradycardia as seen in neurally mediated syncope. A magnetic resonance imaging scan showed a collapsed syrinx from the 3rd cervical to the 12th thoracic vertebra without syringobulbia. Fludrocortisone and beta-blockers led to resolution of symptoms. Partial sympathetic denervation of the legs in syringomyelia might explain the occasional occurrence of postural tachycardia syndrome. Postural tachycardia syndrome may be included as a possible cause of orthostatic symptoms in syringomyelia patients.

Periodic limb movements in syringomyelia and syringobulbia.

Twenty-six patients with syringomyelia were studied with polysomnography to determine the frequency of periodic limb movements (PLM) and its relationship to the presence of a Chiari anomaly, the severity of corticospinal tract involvement, and localization of the syrinx. Sixteen patients showed PLM in stages I and II of non-REM sleep and three PLM also while awake. There were no statistically significant differences in overall disability, corticospinal signs, presence of an associated Chiari anomaly, and disease duration between patients with and without PLM, although there was a trend for patients with PLM to have more severe disease. There was preservation of the lumbosacral enlargement of the spinal cord by the syrinx in all patients with PLM. The latency delay between lower and upper limb muscles was suggestive of conduction along propriospinal pathways. Syringomyelia may lead to an abnormal state of spinal hyperexcitability favoring the appearance of PLM. Detailed magnetic resonance image studies of patients with different localizations of the syrinx cavities may help to determine which tracts are involved in the production of PLM.

Electrodiagnostic findings in syringomyelia.

Electrodiagnostic abnormalities are well known to occur in syringomyelia although the findings are nonspecific. The objective of this work was to describe different types of spontaneous electromyographic (EMG) activity and reflex responses, which may be useful and more specific than conventional findings for the electrodiagnosis of syringomyelia. We studied 43 patients with syringomyelia by four-channel surface EMG and by recording the long-latency responses to distal stimulation of the median and tibial nerves. Continuous motor unit activity (CMUA) was found in 18 patients, synchronous motor unit potentials (SMUP) in 10, respiratory synkinesis (RS) in 5, and myokymic discharges in 4. Long-latency responses (LLR) with latencies ranging from 55 to 150 ms were found in 14 patients. Patients with syringomyelia thus show a wide variation of spontaneous EMG activity. An increase in excitability of spinal motor neurons is probably the basic underlying mechanism.

Respiratory disturbances during sleep in syringomyelia and syringobulbia.

OBJECTIVE: To determine the frequency and types of abnormalities of respiratory control during sleep in syringomyelia and syringobulbia and to provide a basis to predict patients at risk of sudden death. METHODS: Thirty patients (15 male and 15 female; mean age 39.0 +/- 12.6 years) with communicating syringomyelia were divided into two groups: those with evidence of syringobulbia (17 patients) and those without compromise of the medulla or syringomyelia (13 patients). Patients were studied with pulmonary function studies and polysomnography. Respiratory center sensitivity to CO2 (rebreathing technique) was measured in 9 patients. RESULTS: Severely affected patients had mild-to-moderate restriction and individual patients had bilateral diaphragmatic or vocal cord palsy, abnormal respiratory rhythm, prolonged inspiratory time, or an abnormal respiratory response to CO2. Very prolonged central, obstructive, and mixed sleep apneas with low O2 saturation values and a fixed heart rate were recorded in most patients with syringobulbia. Five patients developed severe respiratory complications and died during a follow-up period of 10 years. Respiratory abnormalities failed to correlate with syrinx size. CONCLUSIONS: Severe abnormalities in respiratory rhythm generation during sleep occur in patients with syringobulbia. The respiratory disturbances are not due to muscle weakness and they are not correlated with the size of the cavity. The combination of dysphagia and dysphonia in patients with longstanding syringomyelia and syringobulbia predicted likelihood of respiratory disturbances during sleep.

H-reflex recovery curve in syringomyelia.

H-reflex recovery curves were obtained from 13 patients with cervical syringomyelia to assess motor neurone excitability, and results were compared with control subjects and patients with spasticity due to stroke. The median nerve was stimulated at the elbow and the H-reflex was recorded from the flexor carpi radialis muscle. Double pulses with interstimulus intervals ranging from 75 to 900 ms were delivered. The H-reflex was unobtainable from either limb in two patients with advanced disease and loss of all sensory modalities. H-reflex recovery curves from syrinx patients showed marked facilitation with interstimulus intervals ranging from 150 to 300 ms. Facilitation was higher than in patients with spasticity due to stroke. Results are indicative of an increased motor neurone excitability in patients with cervical syringomyelia.

Involuntary movements and abnormal spontaneous EMG activity in syringomyelia and syringobulbia.

OBJECTIVE: To describe different types of involuntary movements and abnormal spontaneous electromyographic (EMG) activity in patients with syringomyelia. BACKGROUND: A comprehensive study on involuntary movements in patients with syringomyelia has not yet been undertaken, to these authors' knowledge. METHODS: One hundred adult patients with syringomyelia were examined over the last 15 years. Involuntary movements were videotaped and evaluated by two independent observers. Electromyographic recordings were made using bipolar surface electrodes. The H-reflex recovery curve was obtained after stimulation of the median nerve at the elbow and recording from the flexor carpi radialis. RESULTS: Involuntary movements or abnormal postures were observed in 22 patients. Three patients showed segmental spinal myoclonus, nine minipolymyoclonus, and four propriospinal myoclonus. Five patients had unilateral or bilateral hand postural tremor (8-10 Hz). Focal or segmental dystonia was observed in three patients. Electromyography showed spontaneous bursts of grouped action potentials synchronous in muscles innervated by the same spinal segment, synchronous firing of neurogenic motor unit potentials, or continuous motor unit activity. Increased H-reflex responses to conditioning stimuli were found in patients with spinal myoclonus. Long latency responses were obtained during peripheral nerve stimulation in four patients. Four patients had rigidity and abnormal upper limb posture. Respiratory synkinesis was observed in three patients. One patient developed inverse masticatory muscle activity. CONCLUSIONS: Patients with syringomyelia showed a wide spectrum of involuntary movements. An increased excitability of spinal motor neurons was probably the basic underlying mechanism.

Actualizacion de la malformación de Chiari / Up to date on Chiari malformation

Luego del advenimiento de la resonancia magnética como recurso diagnóstico, la malformación de Chiari ha merecido una revisión conceptual y se han implementado nuevas directivas terapéuticas. Se analizan estos nuevos conceptos y los resultados beneficiosos obtenidos en el tratamiento quirúrgico de cinco casos de distintas edades, cuatro de ellos correspondientes a Chiari tipo I y uno a Chiari tipo II. En particular se destaca la mejoría de la clínica y la imagenología determinadas por la hidrosiringomielia asociada, luego de la decompresión de fosa posterior, sin necesidad de actuar sobre las cavidades siringomiélicas(AU)

Actualizacion de la malformación de Chiari / Up to date on Chiari malformation

Luego del advenimiento de la resonancia magnética como recurso diagnóstico, la malformación de Chiari ha merecido una revisión conceptual y se han implementado nuevas directivas terapéuticas. Se analizan estos nuevos conceptos y los resultados beneficiosos obtenidos en el tratamiento quirúrgico de cinco casos de distintas edades, cuatro de ellos correspondientes a Chiari tipo I y uno a Chiari tipo II. En particular se destaca la mejoría de la clínica y la imagenología determinadas por la hidrosiringomielia asociada, luego de la decompresión de fosa posterior, sin necesidad de actuar sobre las cavidades siringomiélicas

Anestesia para cesárea en unapaciente con siringomielia. Reporte de un caso / Anesthesia for cesarean section in a patient with syringomiella. a case report

Paciente femenina de 39 años de edad con diagnóstico de Siringomielia a la que se le realiza cesárea. Se presenta el manejo anestésico y se discute el caso

Siringomielia total asociada a Tumor / Tumor associated total syringomyelia

Se reporta el caso de una mujer de 36 años de edad, con antecedentes de nacimiento por parto distócico y traumatismos vertebrales 25 y 27 años antes del comienzo de su sintomatología, en julio de 1992. Inicia con compromiso motor asimétrico y posterior transtorno de la sensibilidad, alcanzando postración total dos años antes de su ingreso a esta institución. El exámen clínico reveló paraplejia flácida en miembros inferiores, retención urinaria y una clásica disociación siringomiélica con nivel en C7. Se revisa la clasificación, mecanismo patogénico de la siringomielia, su asociación con tumores medulares, y los hallazgos relacionados con esta entidad en la institución. Basados en la revisión de la literatura nacional, latinoamericana y mundial, y a partir de los datos clínicos y la sensibilidad de la Resonancia Magnética nuclear (RMN), se establece el diagnóstico de tumor cérvico-dorsal asociado a siringobulbia y siringomielia

Inverse masticatory muscle activity due to syringobulbia.

The clinical, radiological, and electrophysiological data of a 25-year-old woman with "inverse masticatory muscle activity" due to syringobulbia is presented. This uncommon brain stem syndrome may be due to a disturbance in central programming of mastication.

SEPs and CNS magnetic stimulation in syringomyelia.

Somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) to transcranial and spinal stimulation from upper and lower limb muscles were elicited in 13 patients with syringomyelia. Seven had an associated Chiari type I anomaly. Diagnosis was confirmed by MRI. In 5 cases, SEPs and MEPs were performed before and after surgical treatment. Prolonged central motor conduction times or absent motor responses in upper or lower limbs were found in most patients. The greatest number of abnormalities was disclosed by measurement of CMCT followed by SEPs after tibial nerve stimulation. Two of 5 cases undergoing surgery improved clinically and showed reduction in CMCT after surgical treatment. Our study shows that MEPs were useful in the evaluation of neurophysiological status in syringomyelia patients, helping to estimate anterolateral spinal cord function.

Risk of sudden death during sleep in syringomyelia and syringobulbia.

Clinical, respiratory, and polysomnographic findings in three patients with syringomyelia and syringobulbia who developed severe respiratory complications are described. Neurological examination showed evidence of IXth and Xth cranial nerve involvement with dysphagia and dysphonia, but there were no complaints of serious sleep difficulties. Two patients died during sleep and the other was resuscitated during a nap. All patients showed moderate restrictive ventilatory defects with reduced maximal buccal pressures and one also showed a low ventilatory response to CO2 rebreathing. Protracted central, obstructive, and mixed apnoeas and hypopnoeas were commonly observed during sleep. There were no changes in heart rate during these events. A combination of respiratory and cardiovascular mechanisms might have been responsible for the severe complications described.