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1.
Neurosurg Rev ; 38(1): 89-98; discussion 98-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25323095

RESUMEN

Chordomas are rare, locally aggressive malignancies that often exhibit an insidious natural history and are difficult to eradicate. Surgery and radiotherapy are the treatment mainstays of chordoma, but the chance of local recurrence remains high. Reports of receptor tyrosine kinase (RTK) expression in chordoma suggest that these tumors may respond to kinase inhibitor therapy. Currently, there are no effective chemotherapeutic protocols for chordoma. A tissue microarray containing 74 tumor specimens from primary chordoma patients and 71 from their recurrent tumors for a total of 145 tumor specimens was immunohistochemically analyzed for expression of a number of proteins involved in signal transduction from RTKs. Platelet-derived growth factor receptor-α (PDGFR-α), epidermal growth factor receptor (EGFR), c-Met, and CD-34 were detected in 100, 92, 100, and 59% of cases, respectively. PDGFR-α and c-Met staining was of moderate to strong intensity in all cases. In contrast, total EGFR staining was variable; weak staining was detected in 10 cases. Our results contribute to the understanding of the expression of RTKs in skull base chordomas and support the development of targeted therapies that inhibit RTKs, which may have a synergistic effect for chemotherapy in patients. There were statistically significant correlations between the expression of PDGFR-α, c-Met, and EGFR and disease-free survival. The results nonetheless suggest that chordomas may respond to RTK inhibitors or modulators of other downstream signaling.


Asunto(s)
Cordoma/metabolismo , Receptores ErbB/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Neoplasias de la Base del Cráneo/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Cordoma/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica/métodos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/metabolismo , Adulto Joven
2.
Neurosurg Rev ; 37(1): 79-88, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23999886

RESUMEN

Chordomas are locally invasive tumors that have a tendency to relapse despite optimal treatment. Specific biological markers might be used to describe their behavior. There is currently no agreement regarding the best way to manage intracranial chordomas. We studied the expression of vascular endothelial growth factor receptor 2 (VEGFR-2), inducible nitric oxide synthase (iNOS), and Ki-M1P in 145 paraffin-embedded tumors. The purpose of our study was to determine: (a) the role of potent angiogenic factors VEGFR-2 and iNOS and their relationship to each other in skull base chordoma and (b) the role of monocytes/macrophages as a potential iNOS source in the angiogenic process. A series of 74 chordoma patients for a total of 145 lesions (including 71 recurrent lesions) and 10 specimens from embryonic notochord were investigated for the expression of iNOS, VEGFR-2, Ki-M1P, and CD-34 using immunohistochemistry. In the majority of the chordomas, correlations were found between iNOS and the immunoreactivity of Ki-M1P (r = 0.5303, P < 0.0001). Furthermore, the expressions of Ki-M1P was correlated with VEGFR-2 (r = 0.4181, P < 0.0001). Our results indicate that chordomas may respond to receptor tyrosine kinase inhibitors such as VEGFR-2 or modulators of other downstream signaling molecules. The future of VEGFR-2 and iNOS inhibitors as therapeutic agents in the treatment of chordoma will be clearer over the next years as results of the current clinical trials become available and as the factors regulating angiogenesis and the interactions between these factors are elucidated. However, appropriate functional experiments remain to be conducted to prove such a hypothesis.


Asunto(s)
Anticuerpos Monoclonales/biosíntesis , Cordoma/metabolismo , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Neoplasias de la Base del Cráneo/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/biosíntesis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD34/inmunología , Biomarcadores de Tumor/análisis , Cordoma/patología , Estudios de Cohortes , Femenino , Humanos , Inmunohistoquímica , Macrófagos/metabolismo , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Monocitos/metabolismo , Recurrencia Local de Neoplasia , Neovascularización Patológica/patología , Infiltración Neutrófila , Neoplasias de la Base del Cráneo/patología , Adulto Joven
3.
Minim Invasive Neurosurg ; 53(4): 159-63, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21132606

RESUMEN

BACKGROUND: The purpose of this study was to analyze the value of endoscopic third ventriculostomy (ETV) in patients with shunt malfunction or infection. METHODS: ETV was performed in 263 patients in Greifswald between 1993 and 2008. We reviewed the data of all patients with previous shunts who underwent ETV instead of shunt revision. The procedure was successful when subsequent shunt implantation was avoided. RESULTS: Neuroendoscopy was performed in 30/31 previously shunted patients. The average age of the patients was 26.4 years ranging from 6 months to 69 years (male/female ratio: 18/12). The primary cause of hydrocephalus was aqueductal stenosis in 11, myelomeningocele in 5, posthemorrhagic in 5, postmeningitic in 3, tumor-related obstruction in 2, supracerebellar arachnoid cyst in 2, posttraumatic in 1 and a complex congenital hydrocephalus in 1. ETV was successful in 18 patients (60%) with a mean follow-up period of 51 months. 12 patients (40%) did not benefit from ETV and required a permanent shunt. 11 of them received the shunt within 3 months after failed ETV. ETV failed in all children <2 years of age. A benefit of ETV without subsequent shunt procedures was recognized in 18/27 (66.7%) with an obstructive and 0/3 (0%) patients with a communicating cause of the hydrocephalus. Complications occurred in 2 patients (6.7%). CONCLUSIONS: ETV is a potential treatment option when shunts fail in patients with obstructive hydrocephalus. If MR imaging shows no obstruction, a shunt revision is recommended. Patients with a posthemorrhagic and postmeningitic hydrocephalus are poor candidates for ETV.


Asunto(s)
Hidrocefalia/cirugía , Tercer Ventrículo/cirugía , Derivación Ventriculoperitoneal/instrumentación , Ventriculostomía/efectos adversos , Adolescente , Adulto , Anciano , Niño , Preescolar , Falla de Equipo , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neuroendoscopía/efectos adversos , Neuroendoscopía/métodos , Reoperación/efectos adversos , Resultado del Tratamiento , Derivación Ventriculoperitoneal/efectos adversos , Ventriculostomía/métodos
4.
Minim Invasive Neurosurg ; 52(5-6): 242-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20077366

RESUMEN

A 38-year-old man with a right frontal lobe cyst was treated by endoscopic cystoventriculostomy in 1998. Cyst capsule histology revealed surprisingly an endodermal cyst. The patient was reoperated for cyst expansion by endoscopic re-cystoventriculostomy in 2005. In 2007, the patient suffered from brain abscess formation within the cyst which was punctured. The history was positive for a dental infection. In 2008, a recurrent brain abscess in the cyst occurred. The cyst was completely resected. There was no history of trauma or sinusitis. In all, endodermal cysts may mimic a paraxial arachnoid cyst. It may predispose for recurrent brain abscess formation - especially due to bacteraemia. This report confirms earlier presentations that endodermal cysts should be resected, and endoscopic cyst opening is not sufficient.


Asunto(s)
Absceso Encefálico/diagnóstico , Absceso Encefálico/cirugía , Quistes del Sistema Nervioso Central/diagnóstico , Quistes del Sistema Nervioso Central/cirugía , Infecciones por Enterobacteriaceae/complicaciones , Lóbulo Frontal/microbiología , Adulto , Quistes Aracnoideos/diagnóstico , Absceso Encefálico/microbiología , Quistes del Sistema Nervioso Central/microbiología , Quiste Coloide/diagnóstico , Diagnóstico Diferencial , Enterobacter cloacae/aislamiento & purificación , Quiste Epidérmico/diagnóstico , Humanos , Imagen por Resonancia Magnética , Masculino , Microcirugia , Procedimientos Neuroquirúrgicos , Recurrencia , Tomografía Computarizada por Rayos X
5.
Crit Rev Biomed Eng ; 11(3): 189-250, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6391813

RESUMEN

Within the last two decades, the measurement of intracranial pressure (ICP) advanced from basic research to a useful method in clinical practice. The recording of ICP in clinical diagnosis and therapy requires the knowledge of physical, anatomical and pathophysiological fundamentals, of the different measurement principles and of typical, pathognomonic intracranial pressure patterns. This data will be described in this article. The ICP, and its effects, are based on the anatomy of the almost closed rigid skull which is divided into three "compartments" by pressure-resistent septa (falx, tentorium), and which opens into the spinal dura cavity as a 4th compartment. The pressure is distributed by the CSF, whereby hydrostatic laws must be considered. The brain itself is visco-elastic, and its physical characteristics change in pathological conditions. The pathophysiological effects of intracranial hypertension must be divided into generalized pressure effects and directed pressure actions. The generalized pressure effects are caused by the disturbance of the cerebral blood flow (CBF); their understanding requires the knowledge of the characteristic Pressure-Volume (P/V)-Diagram of the craniospinal space, which can be described by mathematical approximations. The directed actions of an elevated ICP are based on pressure gradients (unequal pressure distribution), which are produced by more rapidly growing local intracranial lesions. These pressure differences cause cerebral mass movements with brain stem incarceration, whereby the "pressure = force per area" - rule must be considered. These anatomical and functional basics are of great importance for the measurement technique; for reliability and safety of ICP registration, the elastic forces of the dura and the brain, the pressure distribution as well as the operative procedure and invasivity of the measurement technique have to be regarded. For clinical routine, less invasive methods using miniaturized transducers for epi- or subdural implantation are favorized above the registration of ventricular pressure, which, however, has its special indications. These problems will be described. Besides a registration of the spontaneous ICP fluctuations, a quantitative determination of the P/V-diagram (compliance, elastance, PVI) and of parameters of the CSF dynamics (resistance, CSF production, Pss) may be useful in clinical practice. In diagnosis, invasive methods with artificial volume load may be used, the techniques will be explained.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Presión Intracraneal , Monitoreo Fisiológico/métodos , Adulto , Edema Encefálico/líquido cefalorraquídeo , Líquido Cefalorraquídeo/fisiología , Circulación Cerebrovascular , Niño , Homeostasis , Humanos , Lactante , Monitoreo Fisiológico/instrumentación , Seudotumor Cerebral/líquido cefalorraquídeo
6.
Neurosurgery ; 25(6): 986-90, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2601833

RESUMEN

A 43-year-old woman presented with progressing signs of a space-occupying brain stem lesion. A computed tomographic scan revealed a hyperdense process located in the pons. Magnetic resonance imaging confirmed the lesion, which had a reticulated core of increased and decreased signal intensity. Vertebral angiography did not show any vascular supply of the process. The patient was operated upon in the lateral park bench position. The lesion, being located close to the exit zone of the trigeminal nerve, could be removed totally with incision of the brain stem and atraumatic vaporization of the tumor tissue with the CO2 laser. Despite the fact that the histopathological examination revealed a cavernous angioma the application of laser energy was judged to be extremely valuable for the surgical procedure. It was concluded that with proper selection of application mode and wattage the CO2 laser may be used for extirpation of vascularized lesions also especially when situated in or close to deep lying vital structures of the brain.


Asunto(s)
Neoplasias Encefálicas/cirugía , Hemangioma Cavernoso/cirugía , Terapia por Láser/métodos , Adulto , Neoplasias Encefálicas/diagnóstico , Femenino , Hemangioma Cavernoso/diagnóstico , Humanos , Imagen por Resonancia Magnética
7.
Neurosurgery ; 40(1): 198-200, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8971844

RESUMEN

OBJECTIVE AND IMPORTANCE: There are several theories regarding the genesis of arachnoid cysts. However, controversy continues over what mechanisms are involved in the formation of the cysts. CLINICAL PRESENTATION: A 6-year-old female patient presented with precocious puberty. The results of a neurological examination were unremarkable. Magnetic resonance imaging revealed a large suprasellar prepontine arachnoid cyst. INTERVENTION: An endoscopic ventriculocystostomy via a right frontal burr hole was performed. During inspection of the cyst, we clearly observed a slit-valve mechanism that was obviously responsible for the formation and enlargement of the cyst. The valve was formed by an arachnoid membrane surrounding the basilar artery. Synchronous with pulsation, the valve opened and closed rapidly. CONCLUSION: A slit-valve mechanism seems to be at least one factor of the genesis of suprasellar prepontine arachnoid cysts.


Asunto(s)
Quistes Aracnoideos/fisiopatología , Endoscopios , Ventriculostomía/instrumentación , Aracnoides/fisiopatología , Quistes Aracnoideos/cirugía , Niño , Femenino , Humanos , Puente/fisiopatología , Puente/cirugía , Flujo Pulsátil/fisiología
8.
Neurosurgery ; 45(3): 508-15; discussion 515-8, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10493373

RESUMEN

OBJECTIVE: The purpose of this study was to determine the safety and efficacy of endoscopic aqueductoplasty in patients with hydrocephalus caused by aqueductal stenosis. The controversy of third ventriculostomy and aqueductoplasty is discussed. METHODS: A series of 17 patients who underwent endoscopic aqueductoplasty is reported. Rigid rod-lens scopes were used for inspecting the aqueductal entry and performing balloon aqueductoplasty. With the aid of a 2.5-mm flexible endoscope, the aqueduct and fourth ventricle were explored and aqueductal membranous obstructions were perforated. Third ventriculostomies were performed simultaneously in nine patients. One aqueductal stent was inserted. In six patients, frameless computerized neuronavigation was used for an accurate approach to the aqueduct. The average duration of the endoscopic procedures was 59 minutes (range, 25-100 min). RESULTS: There was no endoscopy-related mortality. Surgical complications included an asymptomatic fornix contusion and two injuries to the aqueductal roof, which resulted in permanent diplopia due to dysconjugate eye movement (one patient) and transient trochlear palsy (one patient). In addition, two patients developed transient dysconjugate eye movements, and one patient had an asymptomatic epidural hematoma. Eleven patients showed improvement in their symptoms. The conditions of five patients were unchanged. One patient died of stroke 1 month after the operation. No patient required shunting. The ventricles decreased in size in nine patients and were unchanged in the remaining eight patients. CONCLUSION: Endoscopic aqueductoplasty is an effective alternative to third ventriculostomy for the treatment of hydrocephalus caused by short aqueductal stenosis. However, longer follow-up periods are necessary to evaluate long-term aqueductal patency after aqueductoplasty.


Asunto(s)
Acueducto del Mesencéfalo/patología , Acueducto del Mesencéfalo/cirugía , Endoscopía/métodos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Adolescente , Adulto , Niño , Constricción Patológica/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
9.
Neurosurgery ; 30(6): 834-41, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1614583

RESUMEN

According to the hypothesis of Jannetta, an arterial compression of the left root entry zone (REZ) of cranial nerves IX and X by looping arteries could play an important role in the pathogenesis of essential hypertension. In an initial anatomical study, the positions of the left vagus and glossopharyngeal nerves in the skull were radiographically determined in 10 cadavers. By using a pattern of REZ topography developed from this information, the angiographic findings in 107 hypertensive and 100 normotensive patients were then compared retrospectively. In 80% of the angiograms of the hypertensive patients that could be evaluated, an artery crossed the left REZ of cranial nerves IX and X. Most frequently, this was the posterior inferior cerebellar artery (35.3% of cases), followed by the vertebral artery (29.4% of cases) and the anterior inferior artery (19.1% of cases). In 9 cases (13%), both the posterior inferior cerebellar artery and the vertebral artery appeared in the REZ. Frequently, a larger diameter of the left vertebral artery was found. The angiograms of normotensive patients that could be evaluated revealed an artery in the REZ in only 34.5% of cases. Our results support the hypothesis that essential hypertension may be associated with neurovascular compression of the left REZ of cranial nerves IX and X.


Asunto(s)
Angiografía Cerebral , Nervio Glosofaríngeo/diagnóstico por imagen , Hipertensión/diagnóstico por imagen , Síndromes de Compresión Nerviosa/diagnóstico por imagen , Raíces Nerviosas Espinales/diagnóstico por imagen , Nervio Vago/diagnóstico por imagen , Adulto , Anciano , Arteria Basilar/diagnóstico por imagen , Cerebelo/irrigación sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Arteria Vertebral/diagnóstico por imagen
10.
Neurosurgery ; 45(1): 147-51; discussion 151, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10414577

RESUMEN

OBJECTIVE: Trephination of the cranial vault is the oldest known surgical procedure and has often been reported in the literature. The present study was performed to study the incidence, the techniques used, and possible indications for trephinations in the region of Mecklenburg-Vorpommern, the most northeastern German state. METHODS: One hundred thirteen of a total of 115 Neolithic (c. 2000-3500 BC) skulls and eight smaller skull fragments found in the region of Mecklenburg-Vorpommern were examined. Defects and abrasions were detected in 31 of these skulls and underwent further examination (careful microscopic and/or endoscopic examination, three-dimensional computed tomography, and x-rays). RESULTS: Six skulls showed defects resulting from trephination, mainly located along the midline or in the left parieto-occipital region. There was good osteological evidence that at least five of these operations had been survived. Two different techniques for trephination (circular cuts and scraping) had been used. CONCLUSION: From the present study, we conclude that the incidence of trephination in Neolithic skulls in our region is at least 5% and that these operations had been survived in singular cases. There is increasing evidence that these procedures were intended to be curative.


Asunto(s)
Paleopatología , Trepanación/historia , Adolescente , Adulto , Femenino , Alemania , Historia Antigua , Humanos , Masculino
11.
Eur J Surg Oncol ; 29(4): 407-14, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12711300

RESUMEN

The waterjet technique enables precise tissue dissection without thermal damage and with preservation of vessels in general surgery. In neurosurgery, these qualities could help to avoid damage of intact brain parenchyma in tumour resections. The present study reports our first results with this technique in brain metastases. Ten patients with intracranial metastases underwent surgery with the aid of the waterjet. Resection was performed in combination with conventional neurosurgical methods. The follow-up consisted of neurological examination and MRI studies. Intraoperatively, the device was easy to handle. No complications due to the device were observed. Vessels were preserved at pressures below 20 bars. Six of the tumours consisted of soft tissue which was poorly demarcated from the surrounding brain. In these tumours, the waterjet was very helpful. It enabled tumour debulking by aspiration and - more important - precise separation of tumour and brain parenchyma. The remaining four cases were rather hard and well demarcated metastases. In these only separation of the tumour from the surrounding brain was achieved. In conclusion, the waterjet can be applied in surgery of brain metastases without complications. The device appears particularly suitable for soft, poorly demarcated metastases. Further clinical studies with this device are required.


Asunto(s)
Neoplasias Encefálicas/cirugía , Disección/métodos , Agua , Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/secundario , Humanos , Imagen por Resonancia Magnética
12.
J Neurosurg ; 88(3): 496-505, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9488304

RESUMEN

OBJECT: The purpose of this study was to determine the efficacy of endoscopic treatment in patients with intraventricular tumors. METHODS: A series of 30 patients with endoscopically treated intraventricular lesions is reported. The lesions included seven colloid cysts, six astrocytomas, three subependymomas, two ependymomas, and one each of the following: pineoblastoma, pineocytoma/pineoblastoma (intermediate type), epidermoid cyst, pineal cyst, medulloblastoma, arteriovenous hemangioma, cavernoma, choroid plexus papilloma, pituitary adenoma, craniopharyngioma, melanoma, and germinoma. Total tumor resections, partial resections, biopsies, stent implantations, septostomies, and third ventriculostomies were performed. In two cases (two subependymomas > 2 cm in diameter), piecemeal endoscopic resection was ineffective because of the very firm consistency of the tumors. Therefore the endoscopic procedure was discontinued and the tumors were removed microsurgically. In the remaining cases the procedures were completed as planned. Even in the presence of difficulties such as poor orientation or significant bleeding, there was no need to abandon the endoscopic procedure. A total of 28 strictly endoscopic interventions were performed, in which the average duration was 85 minutes (range 35-170 minutes). All colloid cysts and the epidermoid lesion were completely evacuated and the capsules were widely resected. Total extirpation of solid tumors was achieved in five cases, whereas most astrocytomas were partially resected. The hydrocephalus-related symptoms resolved in all of the 22 patients with cerebrospinal fluid pathway obstruction. There were no endoscopy-related deaths. In two cases, major bleeding occurred and was controlled endoscopically. The authors observed one case of meningitis, one of mutism, two of memory loss attributed to forniceal injury, one of transient trochlear palsy after a biopsy specimen of an aqueductal tumor was obtained, and one of transient confusion after a biopsy specimen of a germinoma was obtained. CONCLUSIONS: In the authors' preliminary experience, the endoscopic approach was found to be safe and effective. In this series, it was possible to achieve relief of noncommunicating hydrocephalus, tumor resections, and even complete tumor removals by using endoscopic techniques. Based on the results, the authors believe that endoscopic techniques should be considered in the treatment of selected intraventricular lesions.


Asunto(s)
Neoplasias del Ventrículo Cerebral/cirugía , Endoscopía , Adenoma/cirugía , Adolescente , Adulto , Astrocitoma/cirugía , Biopsia , Encefalopatías/cirugía , Ventrículos Cerebrales/cirugía , Niño , Preescolar , Craneofaringioma/cirugía , Quistes/cirugía , Endoscopía/efectos adversos , Endoscopía/métodos , Ependimoma/cirugía , Quiste Epidérmico/cirugía , Femenino , Germinoma/cirugía , Glioma/cirugía , Glioma Subependimario/cirugía , Hemangioma/cirugía , Hemangioma Cavernoso/cirugía , Humanos , Masculino , Meduloblastoma/cirugía , Melanoma/cirugía , Microcirugia , Persona de Mediana Edad , Glándula Pineal/cirugía , Pinealoma/cirugía , Neoplasias Hipofisarias/cirugía , Estudios Prospectivos , Stents , Factores de Tiempo , Ventriculostomía
13.
J Neurosurg ; 77(1): 103-12, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1307855

RESUMEN

Intraoperative observations and animal experiments suggest that neurovascular compression at the left ventrolateral medulla is a possible etiological factor in essential hypertension. In pursuing this hypothesis, the authors examined the neurovascular relations in the posterior cranial fossa of 24 patients with essential hypertension, of 10 with renal hypertension, and of 21 normotensive control patients. Artificial perfusion of the vessels and microsurgical investigations during autopsy identified the vascular relations at the brain stem and at the root entry zone of the caudal cranial nerves. There was no evidence of neurovascular compression at the ventrolateral medulla on the left side in any patient from the control group or among those with renal hypertension. Two normotensive patients had neurovascular compression at the right ventrolateral medulla by the posterior inferior cerebellar artery. In contrast, all patients with essential hypertension had definite neurovascular compression at the left ventrolateral medulla. Additional compression of the right side was seen in three of these patients. Based on the anatomical appearance, it was possible to define three distinct types of neurovascular compression at the ventrolateral medulla. Common to all three types is the compression of the medulla oblongata at its rostral part just caudal to the pontomedullary junction and lateral to the olive in the retro-olivary sulcus. Comparative histopathological study of the microsurgically examined brain-stem specimens revealed no differences between patients with essential hypertension, those with renal hypertension, and normal controls. There was a structural integrity at the site of neurovascular compression at the ventrolateral medulla. The microanatomical findings of this study show that neurovascular relations at the ventrolateral medulla in essential hypertension give rise to pulsatile compression on the left. This supports Jannetta's hypothesis of neurovascular compression at the left ventrolateral medulla as an etiology of essential hypertension.


Asunto(s)
Hipertensión/etiología , Bulbo Raquídeo/patología , Síndromes de Compresión Nerviosa/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Arterias/patología , Encéfalo/irrigación sanguínea , Constricción Patológica , Nervios Craneales/patología , Femenino , Humanos , Hipertensión/patología , Hipertensión/fisiopatología , Masculino , Bulbo Raquídeo/fisiopatología , Bulbo Raquídeo/ultraestructura , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/patología , Síndromes de Compresión Nerviosa/fisiopatología
14.
J Neurosurg ; 69(6): 919-22, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3193197

RESUMEN

Twenty anesthetized rats were randomly assigned to a nimodipine-treated group or a control group of 10 rats each. Local cerebral blood flow (lCBF) was measured by means of a surface electrode using the hydrogen clearance technique. Systemic arterial pressure (SAP) was varied with administration of norfenefrine or by hemorrhage in order to obtain SAP/cerebral blood flow (CBF) curves under different conditions. In the control group, a typical autoregulation curve was obtained with an lCBF plateau between 70 and 120 mm Hg SAP. The nimodipine-treated animals, however, showed only a slight diminution in the slope of the curve but no real plateau, indicating impairment of CBF autoregulation. In another series, 20 anesthetized rats were randomly assigned to a treatment group or a control group of 10 animals each. Intravenous Evans blue dye was used as a tracer for blood-brain barrier (BBB) function. In both groups, SAP was raised to a level of 180 mm Hg with administration of norfenefrine for 6 minutes. Extravasation of significantly more Evans blue dye was observed in the nimodipine group than in the control group, indicating impairment of the BBB. It is concluded that nimodipine may impair CBF autoregulation, allowing damage to the BBB under hypertensive conditions.


Asunto(s)
Barrera Hematoencefálica/efectos de los fármacos , Circulación Cerebrovascular/efectos de los fármacos , Homeostasis/efectos de los fármacos , Nimodipina/farmacología , Animales , Presión Sanguínea , Electrodos , Azul de Evans , Hipertensión/fisiopatología , Microscopía Fluorescente , Ratas , Ratas Endogámicas , Reología/instrumentación
15.
J Neurosurg ; 94(1): 72-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11147902

RESUMEN

OBJECT: Frameless computerized neuronavigation has been increasingly used in intracranial endoscopic neurosurgery. However, clear indications for the application of neuronavigation in neuroendoscopy have not yet been defined. The purpose of this study was to determine in which intracranial neuroendoscopic procedures frameless neuronavigation is necessary and really beneficial compared with a free-hand endoscopic approach. METHODS: A frameless infrared-based computerized neuronavigation system was used in 44 patients who underwent intracranial endoscopic procedures, including 13 third ventriculostomies, nine aqueductoplasties, eight intraventricular tumor biopsy procedures or resections, six cystocistemostomies in arachnoid cysts, five colloid cyst removals, four septostomies in multiloculated hydrocephalus, four cystoventriculostomies in intraparenchymal cysts, two aqueductal stent placements, and fenestration of one pineal cyst and one cavum veli interpositi. All interventions were successfully accomplished. In all procedures, the navigational system guided the surgeons precisely to the target. Navigational tracking was helpful in entering small ventricles, in approaching the posterior third ventricle when the foramen of Monro was narrow, and in selecting the best approach to colloid cysts. Neuronavigation was essential in some cystic lesions lacking clear landmarks, such as intraparenchymal cysts or multiloculated hydrocephalus. Neuronavigation was not necessary in standard third ventriculostomies, tumor biopsy procedures, and large sylvian arachnoid cysts, or for approaching the posterior third ventricle when the foramen of Monro was enlarged. CONCLUSIONS: Frameless neuronavigation has proven to be accurate, reliable, and extremely useful in selected intracranial neuroendoscopic procedures. Image-guided neuroendoscopy improved the accuracy of the endoscopic approach and minimized brain trauma.


Asunto(s)
Encéfalo/cirugía , Endoscopía , Procedimientos Neuroquirúrgicos , Terapia Asistida por Computador , Adolescente , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Niño , Preescolar , Diseño de Equipo , Estudios de Factibilidad , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/instrumentación , Equipo Quirúrgico , Tomografía Computarizada por Rayos X
16.
J Neurosurg ; 93(2): 237-44, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10930009

RESUMEN

OBJECT: The purpose of this prospective study was to evaluate aqueductal cerebrospinal fluid (CSF) flow after endoscopic aqueductoplasty. In all patients, preoperative magnetic resonance (MR) imaging revealed hydrocephalus caused by aqueductal stenosis and lack of aqueductal CSF flow. METHODS: In 14 healthy volunteers and in eight patients with aqueductal stenosis who had undergone endoscopic aqueductoplasty, aqueductal CSF flow was investigated using cine cardiac-gated phase-contrast MR imaging. For qualitative evaluation of CSF flow, the authors used an in-plane phase-contrast sequence in the midsagittal plane. The MR images were displayed in a closed-loop cine format. Quantitative through-plane measurements were performed in the axial plane perpendicular to the aqueduct. Evaluation revealed no significant difference in aqueductal CSF flow between healthy volunteers and patients with regard to temporal parameters, CSF peak and mean velocities, mean flow, and stroke volume. All restored aqueducts have remained patent 7 to 31 months after surgery. CONCLUSIONS: Aqueductal CSF flow after endoscopic aqueductoplasty is similar to aqueductal CSF flow in healthy volunteers. The data indicate that endoscopic aqueductoplasty seems to restore physiological aqueductal CSF flow.


Asunto(s)
Acueducto del Mesencéfalo/cirugía , Líquido Cefalorraquídeo/fisiología , Endoscopía , Imagen por Resonancia Cinemagnética/métodos , Adolescente , Adulto , Anciano , Acueducto del Mesencéfalo/patología , Femenino , Humanos , Hidrocefalia , Masculino , Persona de Mediana Edad , Estudios Prospectivos
17.
J Neurosurg ; 85(2): 293-8, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8755759

RESUMEN

A prospective study of seven consecutive patients with congenital arachnoid cysts treated endoscopically is reported. The ages of the patients at the time of diagnosis ranged from 6 to 47 years with three patients under 15 years. Two cysts were located in the posterior cranial fossa, four in the middle cranial fossa, and one in the suprasellar-prepontine area. The patients' symptoms included headache, seizures, vomiting, nausea, dizziness, balance problems, and precocious puberty. The authors performed cystocisternostomies and ventriculocystostomies via burr holes with the aid of a universal neuroendoscopic system. Minor bleeding was easily controlled by rinsing. In one case, the endoscopic procedure had to be abandoned because of significant bleeding, which obscured a clear operative view, and an open microsurgical cyst fenestration was performed. The follow-up review periods in this group of patients ranged from 15 to 30 months. There was no mortality or morbidity. Symptoms were relieved in five patients and improved in one. Precocious puberty in one case continued. In six cases, follow-up magnetic resonance images or computerized tomography scans revealed a decrease in the size of the cysts. Although the follow-up period is too short to make statements on long-term outcome, the authors recommend the minimally invasive endoscopic approach for treatment of arachnoid cysts as the first therapy of choice. Should the endoscopic procedure fail, established treatment options such as microsurgical fenestration or cystoperitoneal shunting can subsequently be performed without causing additional risk to the patient.


Asunto(s)
Quistes Aracnoideos/cirugía , Encéfalo/cirugía , Endoscopía , Adolescente , Adulto , Quistes Aracnoideos/diagnóstico , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tomografía Computarizada por Rayos X
18.
J Neurosurg ; 89(5): 861-4, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9817429

RESUMEN

Control of bleeding during dissection is a problem that is still not completely resolved in neurosurgical procedures. To overcome this problem in some settings, the authors, in close collaboration with their institution, developed a new device for blunt dissection of brain tumors that is based on a waterjet technique. This report describes their first experimental and clinical experience with this new method. Numerous cutting experiments were performed in porcine cadaver brains. The best results were obtained using pressures from 4 to 6 bars with a 100-microm tip, which produced very small, precise cuts. Histological evaluation showed no disruption or vacuolization of the surrounding tissue. The authors have used the new device in nine patients (seven with gliomas and two undergoing temporal lobe resections for epilepsy), and no complications have been observed. The waterjet device allowed dissection of the brain tissue while even small exposed vessels were spared injury. The instrument was found to be easy to use. Future investigations will concentrate on adapting this new method to endoscopic surgery and evaluating fluids with low surface tension to avoid foaming and bubbling during open surgery.


Asunto(s)
Encéfalo/cirugía , Disección/métodos , Agua/administración & dosificación , Animales , Encéfalo/patología , Neoplasias Encefálicas/cirugía , Cadáver , Epilepsia/cirugía , Glioma/cirugía , Humanos , Inyecciones a Chorro , Porcinos , Lóbulo Temporal/cirugía
19.
J Neurosurg ; 90(1): 153-5, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10413171

RESUMEN

In recent years, endoscopic third ventriculostomy has become a well-established procedure for the treatment of various forms of noncommunicating hydrocephalus. Endoscopic third ventriculostomy is considered to be an easy and safe procedure. Complications have rarely been reported in the literature. The authors present a case in which the patient suffered a fatal subarachnoid hemorrhage (SAH) after endoscopic third ventriculostomy. This 63-year-old man presented with confusion and drowsiness and was admitted in to the hospital in poor general condition. Computerized tomography scanning revealed an obstructive hydrocephalus caused by a tumor located in the cerebellopontine angle. An endoscopic third ventriculostomy was performed with the aid of a Fogarty balloon catheter. Some hours postoperatively, the patient became comatose. Computerized tomography scanning revealed a severe perimesencephalic-peripontine SAH and progressive hydrocephalus. Despite emergency external ventricular drainage, the patient died a few hours later. Although endoscopic third ventriculostomy is considered to be a simple and safe procedure, one should be aware that severe and sometimes fatal complications may occur. To avoid vascular injury, perforation of the floor of the third ventricle should be performed in the midline, halfway between the infundibular recess and the mammillary bodies, just behind the dorsum sellae.


Asunto(s)
Endoscopía/efectos adversos , Hemorragia Subaracnoidea/etiología , Ventriculostomía/efectos adversos , Cateterismo , Neoplasias Cerebelosas/complicaciones , Ángulo Pontocerebeloso/patología , Coma/etiología , Confusión/etiología , Resultado Fatal , Humanos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Masculino , Persona de Mediana Edad , Seguridad , Fases del Sueño , Tomografía Computarizada por Rayos X
20.
J Neurosurg ; 90(2): 187-96, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9950487

RESUMEN

OBJECT: Decompressive craniectomy has been performed since 1977 in patients with traumatic brain injury. The authors assess the efficacy of this treatment and the indications for its use. METHODS: The clinical status of the 57 patients, their computerized tomography (CT) scans, and intracranial pressure (ICP) levels were documented prospectively in a standard protocol. At the beginning of the study, all patients older than 30 years were excluded. As of 1989 patients older than 40 years were excluded until 1991; since that time patients older than 50 years have been excluded. Primary brain or brainstem injury with fully developed bulbar brain syndrome, loss of auditory evoked potentials (AEPs), and/or oscillation flow in a transcranial Doppler ultrasound examination were contraindications to decompressive craniectomy. A positive indication for decompression was given in the case of progressive therapy-resistant intracranial hypertension in correlation with clinical (Glasgow Coma Scale [GCS] score, decerebrate posturing, dilating of pupils) and electrophysiological (electroencephalography, somatosensory evoked potentials, and AEPs) parameters and with findings on CT scans. Unilateral decompressive craniectomy was performed in 31 patients and bilateral craniectomy in 26 patients. In all cases, a wide frontotemporoparietal craniectomy was followed by a dura enlargement covered with temporal muscle fascia. The outcomes of the treatment were surprisingly good. Only 11 patients (19%) died, three of whom died of acute respiratory disease syndrome. Five patients (9%) survived, but remained in a persistent vegetative state; six patients (11%) survived with a severe permanent neurological deficit, and 33 patients (58%) attained social rehabilitation. Two patients (3.5%) did not have a follow-up examination. The GCS score on the 1st day posttrauma and the mean ICP turned out to be the best predictors for a good prognosis. The results demonstrate the importance of decompressive craniectomy in the treatment of traumatic brain swelling. CONCLUSIONS: Surgical decompression should be routinely performed when indicated before irreversible ischemic brain damage occurs.


Asunto(s)
Edema Encefálico/etiología , Edema Encefálico/cirugía , Lesiones Encefálicas/complicaciones , Adolescente , Adulto , Edema Encefálico/diagnóstico por imagen , Niño , Preescolar , Craneotomía , Femenino , Humanos , Lactante , Recién Nacido , Presión Intracraneal/fisiología , Masculino , Persona de Mediana Edad , Sistema Nervioso/fisiopatología , Complicaciones Posoperatorias , Periodo Posoperatorio , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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