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1.
Cent Eur Neurosurg ; 70(1): 21-6, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19197831

RESUMEN

BACKGROUND: To date, little is known about self-help activities including the acquisition and distribution of information among brain tumour patients and their relatives. The aim of our study was to elucidate patient characteristics, methods of networking and the impact on further treatment. METHODS: A German questionnaire was distributed at nationwide patient meetings and via internet forums. It was returned electronically or by regular mail. RESULTS: Mean age of the 129 patients was 43.2 years. Mean age of the 140 relatives (94% family members) answering the questionnaire was 42.6 years. 51% of the patients and 60% of the relatives had a university degree. 61% of the patients suffered from high-grade tumours, and 80% of the relatives were caring for high-grade tumour patients. The higher the grade of the tumour, the earlier self-help was begun after diagnosis. The majority of the patients (36%) and their relatives (54%) spent between 1-4 h per week on self-help activities. More than 80% used the internet, but more than 85% used print products for the acquisition of information. More than 50% felt that they were not given enough information by their treating physician. Motives for self-help were the acquisition of "independent" information and psychological relief from an exchange with other tumour patients. The vast majority was satisfied with the results obtained, and more than four out of five who responded to the questionnaire exchanged information with other patients. The current therapy was influenced by self-help in more than 50% of cases. CONCLUSION: Physicians treating patients with brain tumours face a subgroup of well-educated people aiming to independently verify and possibly supplement and/or modify their prescribed care. With the steadily increasing use of internet resources, this approach can be expected to expand. Physicians should be prepared to deal appropriately with this subgroup of patients and their relatives to ensure that self-help activities support but do not endanger optimal care.


Asunto(s)
Neoplasias Encefálicas/rehabilitación , Autocuidado/estadística & datos numéricos , Adulto , Neoplasias Encefálicas/epidemiología , Recolección de Datos , Educación , Familia , Femenino , Alemania/epidemiología , Humanos , Internet , Masculino , Persona de Mediana Edad , Motivación , Educación del Paciente como Asunto , Grupos de Autoayuda , Encuestas y Cuestionarios
2.
Acta Neurochir (Wien) ; 150(1): 63-5; discussion 66, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18026707

RESUMEN

The retention of a foreign body during a surgical procedure or the inadvertent migration of an implant are rare but potentially harmful complications. Especially in the case of the former, the legal situation is unequivocal. Nevertheless, the uncomplicated removal and limitation of the operative trauma may be in the interest of the surgeon. We report and illustrate 2 patients in whom the use of intra-operative ultrasound resulted in the safe and elective removal of an intracranial drill tip in one patient and a contraceptive implant located in the ulnar nerve sheath in the other. The characteristic acoustic shadowing artefact could be demonstrated in both examples. In the first patient, intra-operative magnetic resonance tomography could not be used because of the magnetic artefact, and in the second patient, ultrasound was preferred for reasons of simplicity. Intra-operative ultrasound is an appropriate and easily available tool for detection of small foreign bodies beneath the nervous system. The neurosurgeon should be familiar with the typical characteristics of foreign bodies, which is different from other structures.


Asunto(s)
Ecoencefalografía/métodos , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/cirugía , Monitoreo Intraoperatorio/métodos , Nervio Cubital/diagnóstico por imagen , Adulto , Encéfalo/diagnóstico por imagen , Dispositivos Anticonceptivos/efectos adversos , Femenino , Cuerpos Extraños/etiología , Humanos , Masculino , Persona de Mediana Edad , Vaina de Mielina/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Prótesis e Implantes/efectos adversos , Tomografía Computarizada por Rayos X
3.
Acta Neurochir (Wien) ; 149(1): 91-3; discussion 93, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17131069

RESUMEN

Haemorrhagic complications occurring after burr-hole procedures are diagnosed only in symptomatic patients or when postoperative imaging is performed routinely. We report the development of an intracerebral haematoma which occurred during ultrasound-guided burr-hole biopsy. Real-time ultrasound through the same burr-hole enabled us to determine the dynamics of the bleeding and its terminal volume. The operation was finished without further complications and the patient did not experience an impairment of her neurological state. Intra-operative ultrasound is capable of detecting "invisible" complications during burr-hole procedures.


Asunto(s)
Biopsia con Aguja/efectos adversos , Ecoencefalografía , Hemostasis Quirúrgica/métodos , Hemorragia Intracraneal Traumática/diagnóstico por imagen , Hemorragia Intracraneal Traumática/cirugía , Cirugía Asistida por Computador , Femenino , Humanos , Hemorragia Intracraneal Traumática/etiología , Persona de Mediana Edad
4.
Minim Invasive Neurosurg ; 48(4): 213-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16172966

RESUMEN

BACKGROUND AND PURPOSE: We evaluated an advanced concept for patient-based navigation during minimally invasive neurosurgical procedures. METHODS: An infrared-based, off-line neuro-navigation system (LOCALITE, Bonn, Germany) was applied during operations within a 0.5 T intraoperative MRI scanner (iMRI) (Signa SF, GE Medical Systems, Milwaukee, WI, USA) in addition to the conventional real-time system. The three-dimensional (3D) data set was acquired intraoperatively and up-dated when brain-shift was suspected. Twenty-three patients with subcortical lesions were operated upon with the aim to minimise the operative trauma. RESULTS: Small craniotomies (median diameter 30 mm, mean diameter 27 mm) could be placed exactly. In all cases, the primary goal of the operation (total resection or biopsy) was achieved in a straightforward procedure without permanent morbidity. The navigation system could be easily used without technical problems. In contrast to the real-time navigation mode of the MR system, the higher quality as well as the real-time display of the MR images reconstructed from the 3D reference data provided sufficient visual-manual coordination. CONCLUSION: The system combines the advantages of conventional neuro-navigation with the ability to adapt intraoperatively to the continuously changing anatomy. Thus, small and/or deep lesions can be operated upon in straightforward minimally invasive operations.


Asunto(s)
Neoplasias Encefálicas/cirugía , Cuidados Intraoperatorios , Imagen por Resonancia Magnética , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Procedimientos Neuroquirúrgicos/métodos , Cirugía Asistida por Computador , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/patología , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Br J Neurosurg ; 19(2): 128-36, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16120515

RESUMEN

Intrinsic brainstem tumours in adults have a poor prognosis and surgical resection is rarely performed. Encouraged by successful operations on children performed in our department, we began a more aggressive strategy of open operations. Between 1986 and 1997, we operated upon 16 consecutive patients over 16 years of age (five female, 11 male, mean age 36.9 years) who were suffering from intrinsic tumours located in the pons and/or medulla oblongata. The extent of first open resection was 80 - 100% in two of the cases and more than 50% in nine cases. The mean survival time after the first occurrence of symptoms was 88.1 (median 34.5) months, and 39.9 (median 11) months after the first open operation. The rate of 5-year survival from the first occurrence of symptoms was 37.5% (25% after the first open surgical procedure). Thirteen out of 16 patients died within the follow-up period of at least 6.3 years, two of them within the immediate postoperative period. Eleven patients experienced a postoperative deterioration of symptoms from which only four recovered. Eight patients had from WHO grade II astrocytoma and a similar course as patients with higher-grade gliomas (n = 4). Our results indicate that open microneurosurgery for intrinsic brainstem tumours is of questionable benefit for the patient. Although surgery offers the advantages of reliable confirmation of histopathology and may be associated with prolonged survival, neurological deterioration was common and, unlike in paediatric patients, often irreversible.


Asunto(s)
Neoplasias del Tronco Encefálico/cirugía , Glioma/cirugía , Microcirugia/métodos , Adolescente , Adulto , Anciano , Astrocitoma/diagnóstico , Astrocitoma/mortalidad , Astrocitoma/cirugía , Neoplasias del Tronco Encefálico/diagnóstico , Neoplasias del Tronco Encefálico/mortalidad , Niño , Femenino , Glioma/diagnóstico , Glioma/mortalidad , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento
6.
Zentralbl Neurochir ; 64(2): 71-5, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12838475

RESUMEN

Patients and their care providers are increasingly turning to the internet for information. Being faced with this information of very heterogeneous quality, the physician would do well to be informed about the common internet information sources. We investigated the e-mails of a mailing list (or "support group") serving about 380 brain tumour patients and their care providers. The mails were obtained from an archive and grouped according to their topic. Within 6 months, 3,272 e-mails were distributed to every group member. Alternative treatments were the most frequently discussed topics (15 %). These discussions dealt with serious new strategies as well as dubious drugs and methods. A critical attitude towards "quacks" was common, but not the rule. More than 10 % of the mails dealt with debates about therapeutic strategy and about symptoms. The individual course of the participants' illness was often reported very frankly. Emotional support between members played another great role in the support group. Criticism of physicians was rare compared to recommendations of specific therapists (3 % vs. 4 %) and included lack of empathy or sensibility and poor communication between physicians. The brain tumour mailing list is a communication medium for brain tumour patients and their care providers, which distributes and reproduces information of heterogeneous quality. The physician faced with this information should be unbiased but cautious.


Asunto(s)
Neoplasias Encefálicas , Internet , Educación del Paciente como Asunto , Neoplasias Encefálicas/psicología , Neoplasias Encefálicas/terapia , Comunicación , Terapias Complementarias , Progresión de la Enfermedad , Correo Electrónico , Humanos , Relaciones Médico-Paciente , Grupos de Autoayuda
7.
Acta Neurochir (Wien) ; 143(8): 793-9; discussion 799-800, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11678400

RESUMEN

BACKGROUND: Early recognition of emerging delayed neurological deficits (DND) in patients after subarachnoid haemorrhage (SAH) is not always possible by transcranial Doppler sonography. Aim of this study was to investigate a) whether determination of blood flow velocities in deep cerebral basal veins can predict DND in these patients b) the correlation of venous flow velocity to cerebral blood flow (CBF). METHODS: a) We prospectively investigated the mean flow velocity in the basal vein (VBVR), in the middle cerebral artery (VMCA) and in the extracranial internal carotid artery (VICA) in 66 patients after spontaneous SAH. Examinations were performed daily during the first 10 days, using transcranial duplex sonography. Thirty-seven patients had VMCA exceeding 120 cm/s. They were categorised in three groups: 1: no delayed neurological deficit; II: transient DND; III: permanent DND or death associated with vasospasm. b) In another group of 14 patients, interdiane variations in global cerebral blood flow (CBF) measured by the Kety-Schmidt-method were correlated with variations in VBVR, VMCA, and VICA. FINDINGS: a) In patients without deficit, VBVR was significantly elevated above normal values the first day (p < 0.05), and days 5 and 6 (p < 0.1) after VMCA exceeding 120 cm/s. In group III (permanent deficit), flow velocities in the BVR were significantly below normal on day 5 (p < 0.05) and 9 (p < 0.1). b) The correlation between changes in VBVR to changes in CBF (r = 0.78, p < 0.001) was closer than between changes in VMCA to the changes in CBF (r = 0.54, p < 0.05). INTERPRETATION: In case of elevated VMCA, patients with higher VBVR seem to have a better outcome. Changes in CBF correlate better with VBVR than with arterial flow velocities.


Asunto(s)
Venas Cerebrales/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Arteria Carótida Interna/diagnóstico por imagen , Femenino , Humanos , Ataque Isquémico Transitorio/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Arteria Cerebral Media/diagnóstico por imagen , Pronóstico , Estudios Prospectivos , Valores de Referencia , Vasoespasmo Intracraneal/diagnóstico por imagen
9.
Microsc Res Tech ; 52(6): 689-99, 2001 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11276121

RESUMEN

A differential morphological response of mature oligodendrocytes (OL) isolated from human and pig brains to the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and to the nerve growth factor (NGF) was observed. In both cases, OL regenerate their processes; however, the rate and the extension of the process formation of human OL were behind that of pig OL. Presumably, the advanced age of the human tissue in these experiments might have contributed to this decrease in process formation, an effect that was already observed for rat OL [Yong et al. (1991) J Neurosci Res 29:87-99]. The less effectivity of NGF via TrkA, which was immunocytochemically shown in human OL, and of TPA via the protein kinase C (PKC) pathway, may have its common focus on the mitogen-activated protein kinase (MAPK) cascade. In this context, it was noted that only a few studies on aging of mature OL are available. It is conceivable that age-related changes in the properties of OL could be an important factor for their cellular responsiveness during longer lasting demyelinating diseases such as multiple sclerosis. Hence, this review would like to provide a basis for future investigations on the aging of mature OL. The data presently available suggest a preliminary classification of mature OL into three categories.


Asunto(s)
Envejecimiento/fisiología , Oligodendroglía/fisiología , Receptor de Factor de Crecimiento Nervioso/metabolismo , Receptor trkA/metabolismo , Animales , Senescencia Celular/fisiología , Humanos , Factor de Crecimiento Nervioso/metabolismo , Ratas , Porcinos
10.
Neuropsychologia ; 39(3): 231-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11163602

RESUMEN

To investigate the role of unilateral amygdala lesions on processing emotions, 22 drug-resistant temporal lobe epilepsy (TLE) subjects (12 with left-sided and ten with right-sided focus) were tested, after anterior temporal lobectomy or selective amygdalo-hippocampectomy on two associative learning tasks containing emotional and neutral facial expressions, respectively. Volumetric lesion analysis was performed on the basis of 3-D MR images. No effects of lesion side were found in TLE subjects. Taken the extent of amygdala damage into account, an interaction effect could be shown between task (learning of neutral facial expressions versus emotional facial expressions) and group (subjects with little versus considerable amygdala damage), indicating worse performance of subjects with considerable amygdala damage in learning emotional facial expressions. Subjects with considerable amygdala damage were also significantly impaired in learning emotional facial expressions when compared with control subjects.


Asunto(s)
Amígdala del Cerebelo/patología , Emociones , Expresión Facial , Hipocampo/patología , Adulto , Amígdala del Cerebelo/cirugía , Aprendizaje por Asociación , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Hipocampo/cirugía , Humanos , Masculino , Persona de Mediana Edad
11.
J Neuroimaging ; 10(3): 157-61, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10918742

RESUMEN

In a prospective study, 55 patients were examined by transcranial duplex sonography (TCCS) after subarachnoid hemorrhage (SAH) to determine whether additional transcranial duplex examination on the middle cerebral artery M2 segments would aid in the examination of the MCA stem segment. The mean blood flow velocities and pulsatility index were correlated to the occurrence of delayed ischemic neurologic deficits (DIND). Out of 47 patients included, 21 did not experience any delayed deficit (group I), 15 did (group II), and in 11 the extent to which vasospasm contributed to a neurologic deficit was unclear (group III). The highest blood flow velocity and the greatest increase of mean blood flow velocity on 1 day were significantly higher in groups II and III both in M1 and in M2. In 10 patients in group II, where the onset day of DIND was known exactly, Doppler data indicating ischemia before or at the time of DIND were observed in nine. In eight patients, Doppler of the MCA stem alone would have provided enough information to recognize the risk of symptomatic vasospasm; in one patient, only the M2 Doppler gave an indication of ischemic complication. Transcranial duplex sonography may provide additional information to TCD by accurate delineation of M1/M2 vasospasm and therefore may help plan cerebral angiography and neurointerventional treatment.


Asunto(s)
Arteria Cerebral Media/diagnóstico por imagen , Hemorragia Subaracnoidea/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Isquemia Encefálica/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Flujo Pulsátil/fisiología , Vasoespasmo Intracraneal/diagnóstico por imagen
12.
Br J Anaesth ; 84(3): 354-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10793596

RESUMEN

The use of the sitting position in neurosurgery is often associated with decreased arterial pressure (MAP) and stroke volume index (SVI). A shift in blood from the intra- to the extrathoracic compartment may be responsible for this cardiovascular response. However, little is known of the amount of shift in blood volume after transfer from the supine to the sitting position. Therefore, we measured simultaneously changes in intrathoracic blood volume (ITBV) caused by a change in body position in anaesthetized patients. Measurements of cardiac index (CI), ITBV, pulmonary (PBV) and total circulating (TBVcirc) blood volumes were performed in the supine and sitting position. CI, ITBV, PBV and TBVcirc were measured using a thermodye dilution technique. Fluid input was restricted to 14 ml kg-1 before induction of anaesthesia. Change in body position caused a significant decrease in ITBV and was accompanied by a significant decrease in CI, SVI and MAP. Changes in ITBV correlated (r = 0.78) with changes in SVI. Thus a change in blood volume distribution between the intra- and extrathoracic compartment occurred after a change from the supine to the sitting position. Indicator dilution enables quantification of this shift and may be helpful in guiding fluid therapy in selected patients.


Asunto(s)
Volumen Sanguíneo/fisiología , Transferencias de Fluidos Corporales/fisiología , Procedimientos Neuroquirúrgicos/métodos , Postura/fisiología , Adulto , Anciano , Presión Sanguínea/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Volumen Sistólico/fisiología , Posición Supina/fisiología
13.
Acta Anaesthesiol Scand ; 44(4): 378-82, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10757568

RESUMEN

BACKGROUND: In neurosurgical procedures within brainstem structures, corticosteroids are routinely administered to prevent oedema and to reduce intraoperative trauma. After replacing the routine administration of dexamethasone (DX) by high-dose methylprednisolone (MP) during surgery for tumours within brainstem structures, a decreased incidence of intraoperative haemodynamic instability events was observed. To test this hypothesis, a retrospective analysis was performed. METHODS: Peroperative data of 62 surgical procedures of brainstem tumours were retrospectively analysed with respect to haemodynamic instability requiring changes in surgical strategy and/or emergence medication with vasoactive drugs. Severe changes in haemodynamic parameters were defined as a significant increase or decrease in heart rate and/or mean arterial blood pressure greater than 30% compared to baseline values. From 1988 to 1994, intravenous dexamethasone was given peroperatively in 33 patients. After a bolus of 1 mg kg(-1) body weight (BW) 30 min preoperatively, 0.2 mg kg(-1) were given every 4 h. From 1994 until now, methylprednisolone was administered instead of dexamethasone in 29 patients. After an initial bolus of 30 mg kg(-1) BW immediately before surgery, 5.4 mg kg(-1) h(-1) were given 23 h postoperatively. RESULTS: The results of this retrospective analysis suggest that the number of operations with episodes of bradycardia, arterial hypotension (P<0.05), tachycardia and arterial hypertension (P<0.005) was significantly decreased in the group of patients treated with high-dose methylprednisolone. CONCLUSION: The retrospective analysis of the clinical data showed that the routine use of high-dose methylprednisolone was associated with a decreased incidence of haemodynamic instability in a selected group of patients undergoing brainstem surgery. This finding has to be proven in prospective double-blind controlled studies.


Asunto(s)
Tronco Encefálico/cirugía , Dexametasona/administración & dosificación , Glucocorticoides/administración & dosificación , Hemodinámica/efectos de los fármacos , Complicaciones Intraoperatorias/prevención & control , Metilprednisolona/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Adolescente , Arritmias Cardíacas/etiología , Arritmias Cardíacas/prevención & control , Edema Encefálico/etiología , Edema Encefálico/prevención & control , Neoplasias del Tronco Encefálico/cirugía , Niño , Femenino , Humanos , Hipertensión/etiología , Hipertensión/prevención & control , Hipotensión/etiología , Hipotensión/prevención & control , Masculino , Cuidados Preoperatorios , Estudios Retrospectivos
14.
Artículo en Inglés | MEDLINE | ID: mdl-10768051

RESUMEN

OBJECTIVE: Due to the exponential shape of the intracranial volume-pressure relation, simple measurement of epidural, parenchymal or intraventricular intracranial pressure (ICP) in traumatic brain injury (TBI) often fails to early recognize patients with a fulminant development of intracranial hypertension even during recently available methods of tissue PO2 and microdialysis measurements. One approach to this problem could be repetitive intracranial volume provocations to evaluate a trend of the intracranial elastance. Several previously published methods use invasive volume challenge through access to the cerebrospinal fluid (CSF). This pilot study describes changes in intracranial pressure due to variations of airway pressure with BIPAP ventilation maneuvers. PATIENTS AND METHODS: Ten patients with severe TBI were enrolled and completed the study. The inclusion was based on radiologic signs due to TBI in the first CT-scan and the clinical indication for insertion of an ICP monitoring device. Patients with elevated ICP above 20 mm Hg were excluded. The epidural ICP response together with haemodynamic parameters in relation to defined airway pressure changes (delta PAW) was detected. The influence of the duration of delta PAW was evaluated additionally. Data of central venous pressure (CVP), ICP, mean arterial pressure (MAP), cerebral perfusion pressure (CPP), airway pressure (PAW) and blood flow velocity of the middle cerebral artery (VMCA) were analyzed on the basis of differences between the maximum (inspiration) and minimum PAW values (expiration). RESULTS: Elevations of PAW in the range of 20 to 35 cm H2O resulted in changes of the ICPmean from 4.1 to 6.0 mm Hg (r = 0.9, p < 0.05). A correlation was estimated for the changes of systolic arterial pressure (Part) and CPPmean due to PAW variations which ranged between 4.5 and 11.6 mm Hg (r = 0.99, p < 0.05). Concerning the transcranial doppler measurements the data of changes of the blood flow velocity of the middle cerebral artery (VMCA) revealed a positive correlation to PAW with a r = 0.99, p < 0.05. CONCLUSIONS: Elevation of the venous outflow resistance and a transient increase in cardiac output have to be considered as mechanisms for transduction of transthoracic pressure changes to intracranial pressure variations. We conclude, that trends of changes in elastance can be derived from intermittent airway pressure variations. This can be useful in easy and on line dynamic monitoring of ICP in traumatic brain injury.


Asunto(s)
Presión del Aire , Lesiones Encefálicas/fisiopatología , Circulación Cerebrovascular/fisiología , Presión Intracraneal/fisiología , Arteria Cerebral Media/fisiopatología , Presión Sanguínea/fisiología , Presión Venosa Central/fisiología , Hemodinámica/fisiología , Humanos , Hipertensión Intracraneal/diagnóstico , Hipertensión Intracraneal/fisiopatología , Proyectos Piloto , Respiración Artificial
15.
Peptides ; 21(1): 91-9, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10704724

RESUMEN

The presence of functional endothelin converting enzyme (ECE) activity in basilar artery ring segments was investigated by measuring the contractile and relaxant effects of big endothelin (ET)-1. Under resting tension conditions cumulative application of big ET1-1 elicited a concentration-related contraction with the concentration-effect curve (CEC) shifted to the right against ET-1 by a factor of 31 and 29 in segments with the endothelium intact or mechanically removed, respectively. Preincubation with the ET(A) receptor antagonist, BQ123, induced an apparently parallel rightwards shift without affecting the maximum contraction. This shift was more pronounced for ET-1 than for big ET-1. With the putative ECE inhibitor phosphoramidon (10(-3) M) in the bath a small rightwards shift of the CEC for big ET-1 was observed in control segments and a more marked one in de-endothelialized segments. In segments precontracted with prostaglandin (PG) F(2alpha) big ET-1 induced a significant although transient relaxation whereas ET-1 did not. However, in the presence of BQ123 both ET-1 and big ET-1 elicited concentration-related relaxation with a significantly higher maximum effect obtained with big ET-1. The potency was 13 fold higher for ET-1, which is markedly less than that found for contraction. The results, therefore, suggest 1) the presence of functional ECE-activity in the rat basilar artery wall, and 2) differences in the functional ECE activity located in the endothelium and media.


Asunto(s)
Arteria Basilar/efectos de los fármacos , Arteria Basilar/fisiología , Endotelinas/farmacología , Precursores de Proteínas/farmacología , Vasoconstricción/efectos de los fármacos , Animales , Ácido Aspártico Endopeptidasas/antagonistas & inhibidores , Ácido Aspártico Endopeptidasas/metabolismo , Arteria Basilar/ultraestructura , Antagonistas de los Receptores de Endotelina , Endotelina-1/farmacología , Enzimas Convertidoras de Endotelina , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiología , Endotelio Vascular/ultraestructura , Inhibidores Enzimáticos/farmacología , Glicopéptidos/farmacología , Técnicas In Vitro , Masculino , Metaloendopeptidasas , Microscopía Electrónica , Péptidos Cíclicos/farmacología , Ratas , Ratas Sprague-Dawley , Receptor de Endotelina A , Vasodilatación/efectos de los fármacos
16.
Epilepsy Res ; 36(1): 75-82, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10463853

RESUMEN

In the brain, S100 protein and neuron-specific enolase (NSE) are mainly found in glial cells and neurons, respectively. We investigated concentrations of S100 protein and NSE in cisternal cerebrospinal fluid obtained during implantation of foramen ovale electrodes in eight patients with temporal lobe epilepsy (TLE). In addition, the meningeal markers cystatin-C and beta-trace as well as total protein were measured. Patients with trigeminal neuralgia (TN) undergoing glycerol rhizotomy served as controls. S100 protein and NSE levels ipsilateral to the site of seizure onset were significantly higher than in TN. Contralateral TLE values were also markedly but not significantly elevated. The meningeal markers cystatin-C and beta-trace protein as well as total protein did not differ in TLE and TN. We conclude that interictal temporal lobe dysfunction corresponds with neuronal and glial marker elevations in the extracellular space and that site-specific elevations may predict the site of seizure origin biochemically.


Asunto(s)
Cisterna Magna/metabolismo , Epilepsia del Lóbulo Temporal/líquido cefalorraquídeo , Fosfopiruvato Hidratasa/líquido cefalorraquídeo , Proteínas S100/líquido cefalorraquídeo , Adulto , Biomarcadores/análisis , Electroencefalografía , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Childs Nerv Syst ; 15(2-3): 110-6; discussion 117-8, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10230667

RESUMEN

To evaluate intracranial venous haemodynamics in craniosynostosis noninvasively, we measured the blood flow velocities and pulsatility indices in the superior sagittal sinus (SSS) and the middle and the anterior cerebral artery during the perioperative course in 21 children undergoing repair of craniosynostosis involving the midline sutures, using transcranial colour-coded duplex sonography (TCCS). An age-matched group of 12 healthy children was examined in like manner for comparison. In the healthy group, the mean pulsatility index (PI) in the SSS was 0.22 and the mean resistance index (RI) 0.20. The mean preoperative PI and RI in the synostosis group were significantly higher [0.41 and 0.34, respectively (P<0.01)], but fell to 0.19 and 0.17 (P<0.01) in the postoperative course. Our results indicate that in craniosynostosis there is an altered venous haemodynamics in the SSS, which can be observed noninvasively by TCCS.


Asunto(s)
Venas Cerebrales/diagnóstico por imagen , Senos Craneales/diagnóstico por imagen , Craneosinostosis/complicaciones , Craneosinostosis/cirugía , Hipertensión Intracraneal/diagnóstico por imagen , Ultrasonografía Doppler Dúplex/métodos , Velocidad del Flujo Sanguíneo , Venas Cerebrales/fisiopatología , Femenino , Hemodinámica/fisiología , Humanos , Lactante , Hipertensión Intracraneal/etiología , Masculino , Estudios Prospectivos , Flujo Pulsátil , Resultado del Tratamiento
19.
Surg Neurol ; 52(6): 630-7, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10660033

RESUMEN

BACKGROUND: Space-occupying subdural hygromas are a late complication of severe traumatic brain injury (TBI) and may delay the patient's recovery. To evaluate the risk factors involved, we performed a semiretrospective, -prospective analysis of three groups of patients, which differed with regard to the techniques used in the management of their cerebral perfusion pressure (CPP) and colloid osmotic pressure (COP) to determine the occurrence of space-occupying subdural hygromas. PATIENTS AND METHODS: Between 1989 and 1997 we examined 696 patients after a severe TBI: Group 1. 1989-1994 mean CPP: 67 (elevated for therapeutic reasons by catecholamines, if necessary), mean COP: 19. Group 2. January 1995-October 1996, mean CPP: 77, mean COP: 20. Group 3. November 1996-December 1997, mean CPP: 79, mean COP: 23 (elevated for therapeutic reasons by infusions of colloids). The groups were comparable for other criteria. RESULTS: Compared to Group 1, Group 2, with a high CPP but lower COP, showed a significantly higher (p < 0.01; chi2-test with correction of Yates) percentage of posttraumatic subdural hygromas with space-occupying aspects, clinical signs of bradycardia, hypertension and impaired consciousness requiring surgery (Group 1: 1.75%; Group 2: 10.46%; Group 3: 0%). In Group 3 we saw no patient with a space-occupying hygroma. CONCLUSION: We conclude that iatrogenic elevated CPP, which has been reported to be helpful in preventing secondary ischemic damage after a severe TBI, may be harmful to a patient if the COP is not maintained within physiological ranges.


Asunto(s)
Presión Sanguínea/fisiología , Lesiones Encefálicas/complicaciones , Encéfalo/irrigación sanguínea , Efusión Subdural/etiología , Equilibrio Hidroelectrolítico/fisiología , Adulto , Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/fisiopatología , Femenino , Humanos , Presión Intracraneal/fisiología , Masculino , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Efusión Subdural/diagnóstico por imagen , Efusión Subdural/fisiopatología , Efusión Subdural/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
Eur J Ultrasound ; 7(2): 83-91, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9614276

RESUMEN

OBJECTIVE: We intended to evaluate the value of transcranial color-coded duplex sonography (TCCS) in the management of patients after clipping of an aneurysm of the middle cerebral artery. Question was whether this method was able to predict poor clinical outcome by detection of local circulation disorders in the postoperative course. METHODS: A series of 15 consecutive patients was examined daily by TCCS. Special attention was paid to the branches of the middle cerebral artery distal from the clip (M2 branches). We correlated the TCCS results to the clinical outcome and occurrence of infarction on CCT. RESULTS: In six patients, one or more M2 branches could not be found in the immediate postoperative course, but reappeared after a period of 1-12 days in five patients. The three patients with a missing signal for more than 4 days suffered from infarction of the dependent territory and permanent neurological deficit not due to vasospasm of the middle cerebral artery. In the nine patients with constant TCCS signals, there was only one infarction due to pre-hospital systemical hypotension. CONCLUSION: TCCS cannot give exact postoperative information about incidental vessel occlusion during surgery for MCA aneurysms because M2 branches can remain invisible for some days without being occluded, but this invisibility seems to be coupled with ischemic complications.


Asunto(s)
Aneurisma Intracraneal/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía Doppler Dúplex , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/etiología , Circulación Cerebrovascular , Estudios de Evaluación como Asunto , Femenino , Hemodinámica , Humanos , Aneurisma Intracraneal/complicaciones , Masculino , Persona de Mediana Edad
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