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1.
Am J Otolaryngol ; 36(4): 547-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25749259

RESUMO

PURPOSE: Esthesioneuroblastoma is an uncommon malignancy of the head and neck for which there is no defined treatment protocol. The purpose of this study is to report our experience with the treatment and patterns of failure of this disease. METHODS AND MATERIALS: From 1994 to 2012, 37 previously unreported patients with esthesioneuroblastoma were evaluated, and 32 eventually treated for cure at 2 academic medical centers. All patients were staged with Kadish criteria. The mean and median follow-ups were 96.1 and 76.5 months respectively (range 6-240 months). RESULTS: The Kadish stage was A in 6 patients, B in 13 patients, and C in 13 patients. Four patients were initially treated with concurrent chemo-radiation therapy. Twenty-eight patients were treated with primary surgery. Two (2) underwent open medial maxillectomy and 26 underwent craniofacial resection (open - 17, endoscopic - 9). Three patients received curative surgical resection only. Seven patients failed either within the cranial axis or distantly, 6 of the 7 are dead of disease, 10-194 months following initial treatment. Six patients had isolated neck recurrences, 4/6 were salvaged with neck dissection and additional chemo-radiation and remain alive 30-194 months following initial treatment. Estimated overall survival rate at 10 years was 78% based on Kadish and T stages. CONCLUSION: In this retrospective analysis of 32 patients, Kadish stage C and stage T3/T4 tumors were associated with worse outcome. Total radiation dose of 60 Gy, margin status, patient age, were not found to have significant prognostic value.


Assuntos
Estesioneuroblastoma Olfatório/terapia , Cavidade Nasal , Recidiva Local de Neoplasia/terapia , Neoplasias Nasais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Intervalo Livre de Doença , Estesioneuroblastoma Olfatório/diagnóstico , Estesioneuroblastoma Olfatório/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/mortalidade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Falha de Tratamento , Estados Unidos/epidemiologia
2.
J Neurol Surg B Skull Base ; 73(2): 139-44, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23542642

RESUMO

The most prominent stigma of supratentorial skull base surgery is the defect caused by wasting of the temporalis muscle by denervation, devascularization, or rotation of the muscle. Any of the above may lead to a unilateral temporal deformity informally referred to patients as "the divot in my head." Abdominal free fat grafting has been used by surgeons for years to close posterior fossa defects with excellent results. We present our experience using abdominal free fat grafts to improve cosmetic results and to prevent cerebrospinal fluid leaks in supratentorial skull base surgery. The basic technique and its benefits are described.

3.
Neurosurgery ; 60(4 Suppl 2): 243-7; discussion 247-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17415159

RESUMO

OBJECTIVE: Accurate placement of ventricular catheters decreases the incidence of proximal catheter failure. The use of a frameless, interactive neuronavigational system can optimize catheter placement. METHODS: Thirty-four ventricular catheters were placed using a Medtronic electromagnetic frameless neuronavigational system (Medtronic Navigation, Inc., Louisville, CO) during a 12-month period. The patients ranged in age from 11 months to 79 years; the mean age was 40.8 years. Nineteen male and 12 female patients participated in the study. The indications for ventricular catheter placement included obstructive hydrocephalus, normal pressure hydrocephalus, pseudotumor cerebri, intrathecal therapy, and tumor cyst aspiration. RESULTS: No proximal failures have been reported to date. One infection necessitated shunt removal. Three postoperative deaths occurred because of non-catheter-related events. CONCLUSION: Frameless neuronavigation in the placement of ventricular catheters assures accurate catheter placement, thereby decreasing the incidence of proximal catheter failure. The absence of rigid head fixation allows additional cohorts to benefit from the apparatus. The use of the electromagnetic system provides a safe, simple, and easy adjunct to optimal catheter placement.


Assuntos
Encefalopatias/cirurgia , Cateterismo/instrumentação , Ventrículos Cerebrais/cirurgia , Hidrocefalia/cirurgia , Neuronavegação/instrumentação , Procedimentos Neurocirúrgicos/instrumentação , Adolescente , Adulto , Idoso , Encefalopatias/complicações , Cateterismo/efeitos adversos , Cateterismo/métodos , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/complicações , Lactente , Masculino , Pessoa de Meia-Idade , Neuronavegação/métodos , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/etiologia , Fatores de Tempo , Resultado do Tratamento , Derivação Ventriculoperitoneal/instrumentação , Derivação Ventriculoperitoneal/métodos
4.
Surg Neurol ; 62(5): 463-7; discussion 467, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15518860

RESUMO

BACKGROUND: Intracranial dural arteriovenous fistulas account for 10 to 15% of all intracranial arteriovenous malformations. Tentorial dural arteriovenous fistulas with spinal medullary venous drainage causing spinal cord myelopathy are very rare, but have been previously described. We describe a case using a cranio-orbito zygomatic approach with intraoperative angiography for the surgical treatment of a tentorial artery dural arteriovenous fistula causing spinal cord myelopathy. CASE PRESENTATION: A 42-year-old male presented complaining of a 1-year history of incoordination and dizziness and a 2-month history of progressive myelopathy with bowel and bladder incontinence. The patient had magnetic resonance imaging (MRI) performed along with cerebral and spinal angiography that revealed a right tentorial artery dural arteriovenous fistula with spinal medullary venous involvement down to T11. Angiographic embolization was attempted, but selective catheterization was unsuccessful. The patient underwent a cranio-orbito zygomatic approach with obliteration of the dural arteriovenous fistula. An intraoperative angiogram confirmed complete obliteration of the dural arteriovenous fistula. CONCLUSION: Intracranial dural arteriovenous fistulas are a rare cause of spinal cord myelopathy. When a patient presents with suspicion of spinal dural fistula and negative spinal angiography, an intracranial origin should be suspected and a cerebral angiogram performed. Skull base approaches along with intraoperative angiography provide an alternative modality for obliteration of the dural arteriovenous fistula nidus, thereby eliminating the venous congestion and hence the spinal cord ischemia.


Assuntos
Fístula Arteriovenosa/complicações , Fístula Arteriovenosa/cirurgia , Procedimentos Neurocirúrgicos/métodos , Doenças da Medula Espinal/etiologia , Adulto , Fístula Arteriovenosa/patologia , Angiografia Cerebral , Dura-Máter/patologia , Dura-Máter/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Monitorização Intraoperatória , Base do Crânio/cirurgia , Zigoma/cirurgia
7.
Skull Base ; 11(1): 13-23, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17167600

RESUMO

Transverse-sigmoid sinus dural arteriovenous malformations (DAVM) are uncommon vascular lesions for which complete cure may be difficult to obtain. A wide variety of treatments for these lesions include observation, arterial compression, surgical resection, and endovascular embolization. We propose that transverse-sigmoid sinus DAVM can be completely cured by occluding the ipsilateral dural sinus with detachable balloon and Guglielmi detachable coils (GDC) coils before arterial feeder embolization with histoacryl. Three patients who presented with pulsatile tinnitus and normal magnetic resonance imaging (MRI) studies underwent angiography, which demonstrated transverse-sigmoid sinus DAVM. All three patients wer treated with retrograde transvenous sinus embolization with complete occlusion of the transverse-sigmoid sinus with detachable balloons and GDC coils with preservation of the vein of Labbé. Subsequently, the various feeders from the external carotid artery were embolized. The tentorial arteries arising from the ipsilateral internal carotid arteries were not embolized in any of the cases, which were still contributing to the DAVM. Complete cure with thrombosis of the tentorial branch of the internal carotid artery (ICA) was seen on follow-up angiogram 1 day after embolization in one patient and on 4-week and 6-week follow-up angiograms in the other two patients. Complete occlusion of the transverse sinus proximal to the vein of Labbé, in spite of incomplete arterial feeder embolization, can result in complete cure of the transversesinus dural AVF if adequate time is given for the remaining feeders to occlude, once the fistula is obliterated.

8.
Skull Base ; 11(3): 207-18, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17167622

RESUMO

The etiology, classification, clinical presentation, complications, and intravascular routes to image and treat carotid-cavernous fistulas percutaneously are described. Endoarterial and transvenous approaches (through the jugular, inferior petrosal, or cavernous veins) are discussed in relation to the etiology, size, and characteristics of the fistulas, as well as in relation to the planned therapeutic approach and its possible complications. Possible outcomes, with particular attention to the internal carotid circulation, side effects, and complications also are discussed in relation to etiology and type of fistula. Four exemplary cases are presented.

10.
Skull Base Surg ; 10(3): 125-30, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-17171136

RESUMO

Mastery of the three-dimensional anatomic relationships of the cranial base/paranasal sinuses is required to reduce the incidence of iatrogenic surgical complications, facilitate complete tumor extirpation, and enhance functional outcomes. Real-time intraoperative localization technology is one method available to assist the cranial base surgeon. We report our institutional experience with the StealthStationtrade mark treatment guidance platform. Eighty-eight consecutive patients with pathology of the cranial base/paranasal sinuses were operated on with the aid of real-time frameless stereotactic localization. Preoperative image data sets were acquired with either CT or MRI scans. Patient demographics, accuracy of the data sets, surgical approaches, pathology, complications, and further applications of this technology are presented. Procedures were performed on 47 women and 41 men ranging in age from 6 to 85 years. In these 88 procedures, 44 MRI and 44 CT scans with a mean accuracy of 1.57 and 1.23 mm, respectively, were used. Approaches to the cranial base included midface degloving (25), endoscopic (23), craniofacial (13), maxillectomy (12), rhinotomy without maxillectomy (5), transoral (5), pterional (2), transcondylar (1), and transcervical (2). Indications for surgery included severe inflammatory disease of the paranasal sinuses with epidural or subdoral abscess, or both (7), cerebrospinal fluid fistula or encephalocele, or both (11), and 40 benign and 30 malignant tumors. Complications occurred in 10 of 88 patients (11%). Real-time intraoperative localization can be applied to cranial base surgery in a variety of scenarios. The instantaneous transfer of imaging data to the surgical field is useful in localizing pathology, enhancing operative safety, and reducing morbidity, thereby improving outcomes. This technology will certainly play an integral role in minimizing complications and improving surgical outcomes as cranial base surgery moves into the next millennium.

11.
Am J Rhinol ; 13(1): 17-21, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10088024

RESUMO

Abnormalities of the clivus/skull base occur most commonly as a result of disease spread from adjacent structures, but can also occur from primary involvement of the clivus. Traditionally, definitive diagnosis was made by CT guided biopsy or craniotomy. However, lesions can occur in this area that are not amenable to CT guided biopsy or craniotomy. Endoscopic transsphenoidal surgery can provide a safe method for obtaining a clival biopsy, debulking of tumor tissue, or definitive treatment without the morbidity and mortality of a craniotomy. This study was designed to describe our experience with the endoscopic approach to the skull base and clivus via the sphenoid sinus. A series of seven patients underwent endoscopic transsphenoidal biopsy of a sphenoid clival lesion. All patients avoided anticipated craniotomy, and definitive pathology was obtained in five of six patients. In two cases, excisional biopsy proved to be therapeutic. There were no deaths, and major complications included one CSF leak and one intraoperative hemorrhage, both of which were controlled immediately. The experience gained with these patients demonstrates the feasibility and safety of this new application of endoscopic sinus surgery for the diagnosis and possible treatment of lesions of the sphenoid and clivus.


Assuntos
Endoscopia/métodos , Osso Esfenoide/patologia , Seio Esfenoidal/patologia , Adulto , Idoso , Biópsia/métodos , Criança , Contraindicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Neoplasias dos Seios Paranasais/patologia , Neoplasias dos Seios Paranasais/cirurgia , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/cirurgia , Seio Esfenoidal/diagnóstico por imagem , Seio Esfenoidal/cirurgia , Tomografia Computadorizada por Raios X
12.
Surg Neurol ; 51(2): 117-24; discussion 124-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10029414

RESUMO

BACKGROUND: The actual incidence of residual aneurysm after clipping is unknown. The natural history of residual aneurysm can be regrowth and hemorrhage. Intraoperative angiography offers a cost-effective, safe interdiction to the problem of residual aneurysm and parent vessel stenosis. METHODS/RESULTS: Forty consecutive patients harboring 54 aneurysms underwent 42 operative procedures to clip 52 aneurysms, during which 220 intraoperative angiographic runs were performed. Ninety-three percent of the procedures were performed on patients with acute subarachnoid hemorrhage. There were 4 giant (>2.5 cm, 4/52 = 8%, all anterior circulation), 21 large (1.0-2.5 cm, 21/52 = 40%, 16/ 21 = 76% anterior circulation, 6/21 = 28% posterior circulation), and 27 small (<1.0 cm, 27/52-52%, 22/27 = 81% anterior circulation, 5/27 = 18% posterior circulation) aneurysms. Intraoperative angiography led to clip adjustment in 18/52 = 34% of aneurysms (4/18 = 22% for parent artery stenosis, 8/18 = 44% for residual aneurysm and 6/18 = 33% for both). Of the 18 adjustments made, 16 = 88% were made on giant or large aneurysms and two were small (one was a complex anterior communicating and one was a vertebral junction aneurysm). Follow-up angiography was performed on 26/42 = 62% of operative cases. Postoperative angiography confirmed intraoperative angiography in all cases. Two complications occurred during 220 angiographic runs: one embolic stroke and one incident of equipment failure. CONCLUSION: A grading scale was applied to test the relationship between anatomical site and size as they relate to the necessity for clip adjustment for complete aneurysm obliteration and/or parent artery compromise. Significance was related to site (basilar bifurcation, anterior communicating, middle cerebral bifurcation, and ophthalmic) and size (>1.0 cm), both as independent and codependent variables. An analysis of the cost-effectiveness of intraoperative angiography was demonstrated.


Assuntos
Angiografia Cerebral , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Angiografia Cerebral/economia , Análise Custo-Benefício , Honorários Médicos , Feminino , Custos Hospitalares , Humanos , Illinois , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/economia , Ligadura/métodos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Hemorragia Subaracnóidea/etiologia , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/economia
13.
Exp Cell Res ; 244(1): 310-8, 1998 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-9770374

RESUMO

The objective of this study is to determine the role of arachidonic acid (AA) in cell proliferation by inhibiting AA synthetic enzyme phospholipase A2 (PLA2) and to determine its involvement in the role of the second messenger intracellular calcium (Ca2+). Methods used to determine the effects on proliferation of cell cultures of primary meningioma and astrocytoma U373-MG included treatment with micromolar concentrations of PLA2 inhibitors 4-bromophenacylbromide and quinacrine. Effects of these drugs on proliferation were further investigated by the application of concentrations that inhibit growth by 50% while antagonizing these agents with AA replacement. Free cytosolic Ca2+ was measured with the use of fluorescent dye Fura-2 during PLA2 agonist/antagonist studies. These Ca2+ measurements were performed in the absence of extracellular Ca2+ to identify the contribution of intracellular Ca2+ sources. PLA2 inhibition resulted in decreased growth of cultured astrocytoma and meningioma cells in a dose-dependent manner in the micromolar range. This inhibitory effect was antagonized by the addition of AA. PLA2 inhibition caused an elevation of basal-cytosolic-free [Ca2+] while depleting internal Ca2+ stores. These Ca2+ changes were also antagonized by the addition of AA. In conclusion, these results demonstrate that AA, a PLA2 enzyme product, is involved in regulating the growth rate of these cell types. The PLA2 pathway also regulates the maintenance of the internal Ca2+ stores. Ca2+ is known to be a growth-related intracellular second messenger. These results suggest that the growth regulatory functions of AA are mediated by Ca2+-dependent mechanisms.


Assuntos
Sinalização do Cálcio/fisiologia , Fosfolipases A/metabolismo , Fosfolipases A/fisiologia , Astrocitoma/enzimologia , Cálcio/agonistas , Cálcio/antagonistas & inibidores , Divisão Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Eicosanoides/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores do Crescimento/antagonistas & inibidores , Inibidores do Crescimento/metabolismo , Inibidores do Crescimento/fisiologia , Humanos , Masculino , Meningioma/enzimologia , Fosfolipases A/antagonistas & inibidores , Fosfolipases A2 , Células Tumorais Cultivadas
14.
J Neurosurg ; 89(1): 139-41, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9647185

RESUMO

Cervical spondylosis is a disease that is often attributed to aging and considered the result of degenerative changes in the spine. The idea that there is a genetic predisposition to develop diseases of the skeletal elements of the spine has been discussed previously, but has never been proven conclusively. The authors report three cases of severe cervical spondylosis in patients who are first-degree relatives: a mother and her two sons. All three individuals had cervical disc herniations and stenosis at C3-4, C4-5, C5-6, and C6-7, and all three required decompressive procedures. The location and degree of cervical spondylosis were as similar among these three patients as they have been in identical twins reported in other studies. Such familial inheritance of cervical spondylosis has been reported only once. The existence of familial cervical spondylosis is not an unrealistic proposal because other studies have shown that genetics determines the shape of one's spine and that similar spines tend to degenerate in similar ways. Therefore, genetic counseling for a family such as the one reported here may prove to be of great benefit to warn siblings that they are at high risk for cervical spine injury. However rare it might be, familial cervical spondylosis may be a phenomenon that any spine surgeon should suspect in a family with cervical spine abnormalities found in several members.


Assuntos
Vértebras Cervicais/patologia , Osteofitose Vertebral/genética , Adulto , Envelhecimento/patologia , Suscetibilidade a Doenças , Discotomia , Feminino , Aconselhamento Genético , Humanos , Deslocamento do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite/complicações , Fatores de Risco , Fusão Vertebral , Osteofitose Vertebral/etiologia , Osteofitose Vertebral/cirurgia , Estenose Espinal/genética , Estenose Espinal/cirurgia
15.
Neurosurgery ; 41(3): 615-9; discussion 619-20, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9310979

RESUMO

OBJECTIVE: Intimate to the application of lateral transtemporal approaches to the cranial base are the identification, manipulation, and/or the sacrifice of the venous anatomy of the inferolateral temporal lobe and the superior petrosal sinus and the transection of the tentorium. This study demonstrates the relationship and variability of the venous drainage of the lateral and inferior surfaces of the temporal lobe. METHODS: Twenty-one specially prepared, injected cadaver specimens yielded 40 temporal lobes for examination. The venous systems in these specimens were traced from their origins on the temporal lobe (venous drainage complexes) to the transverse/petrosal sinuses, and the geometry of these venous complexes (venous configuration) was noted. The measurements of each complex's entry to the sinuses were noted. RESULTS: Four distinct venous drainage complexes were identified: 1) the lateral complex, 2) the anteroinferior complex, 3) the medial-inferior complex, and 4) the posteroinferior complex. Three basic venous configurations were found: 1) the candelabra of veins uniting to form one large draining vein, 2) multiple independent draining veins, and 3) venous lakes running in the tentorium before entering the sinuses. The lateral complex, incorporating the classic "vein of Labbé," was present in 100% of the specimens. However, in the majority of cases, it did not represent the dominant venous drainage of the lateral and inferior surfaces of the temporal lobe. CONCLUSION: An understanding of the complexity and diversity of the venous drainage complexes and their configurations is necessary to avoid venous complications during lateral cranial base surgery.


Assuntos
Veias Cerebrais/anatomia & histologia , Craniotomia/métodos , Base do Crânio/irrigação sanguínea , Lobo Temporal/irrigação sanguínea , Cavidades Cranianas/anatomia & histologia , Humanos , Processamento de Imagem Assistida por Computador , Valores de Referência , Base do Crânio/cirurgia , Lobo Temporal/cirurgia
16.
Surg Neurol ; 46(5): 450-3; discussion 453-4, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8874544

RESUMO

BACKGROUND: The development of frameless stereotaxis allows for repetitive intraoperative localization with millimeter accuracy. High-resolution computed tomographic (CT) angiography provides multiplanar, three-dimensional imaging of cerebral vascular lesions. The image data set generated during CT angiography can be used for localization in frameless stereotaxis when performed with appropriate fiducials in place. METHODS: The feasibility of melding these two technologies was tested on a patient with a small (5 mm), distal ruptured posterior inferior cerebellar artery aneurysm, which was visualized by CT angiography and localized by frameless stereotaxis. RESULTS: Visualization by CT angiography and intraoperative localization by frameless stereotaxis were successful. CONCLUSIONS: The practical application of this technology meld is demonstrated in this sample case. Applications to distal anterior cerebral artery aneurysms, abnormal flow-related aneurysms associated with arteriovenous malformations, and mycotic aneurysms are discussed.


Assuntos
Cerebelo/irrigação sanguínea , Aneurisma Intracraniano/cirurgia , Radiocirurgia/métodos , Angiografia/métodos , Artérias/cirurgia , Craniotomia , Desenho de Equipamento , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiocirurgia/instrumentação , Tomografia Computadorizada por Raios X/métodos
17.
Neurosurgery ; 39(4): 743-6, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8880767

RESUMO

OBJECTIVE: The primary objective of this study is to present an alternative technique to closure of anterior cranial fossa cerebrospinal fluid (CSF) leaks. This study also serves to review our experience with our technique and presents some technical "tricks" we have learned through experience. METHODS: The design of this study is a clinical chart review. The setting is an academic medical center. RESULTS: Eight patients were referred for closure of postsurgical CSF leaks. Seven of eight patients underwent closure with one attempt and closure was achieved after a second attempt in one patient. Follow-up ranged from 1.5 to 4.0 years. There were no complications. No patient developed an acute or delayed episode of meningitis. CONCLUSION: The technique of endoscopic closure of a CSF leak is a safe and effective means for closure of a postsurgical anterior cranial fossa CSF fistula when performed by an experienced operator.


Assuntos
Rinorreia de Líquido Cefalorraquidiano/cirurgia , Craniotomia , Endoscopia , Complicações Pós-Operatórias/cirurgia , Adenoma/cirurgia , Adulto , Idoso , Neoplasias Encefálicas/cirurgia , Rinorreia de Líquido Cefalorraquidiano/diagnóstico , Cordoma/cirurgia , Craniofaringioma/cirurgia , Feminino , Humanos , Hipofisectomia , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Neoplasias Hipofisárias/cirurgia , Complicações Pós-Operatórias/diagnóstico , Reoperação , Tomografia Computadorizada por Raios X , Resultado do Tratamento
18.
Surg Neurol ; 46(2): 172-80, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8685828

RESUMO

The Decade of the Brain has brought recognition of the contributions neurological surgery has made to modern medicine, and neurological surgery training programs are a cornerstone of these achievements. While neurosurgeons are celebrating their achievements, however, a number of social, political, and administrative issues threaten to undermine the future of these programs. We discuss the ramifications of departmental status to the future of neurological surgery. These include the implications for operative experience-for example, carotid endarterectomy, spine instrumentation, acoustic tumors-the economic impact of a department versus a division, the ability to direct research, administrative input at the institutional level, and self-determination. We discuss the requirements for programmatic change and recommendations for national support.


Assuntos
Educação Médica/organização & administração , Neurocirurgia/educação , Humanos , Estados Unidos , Universidades , Recursos Humanos
19.
J Neurooncol ; 29(2): 143-8, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8858519

RESUMO

Lazaroids (or 21-aminosteroids) are potent lipid peroxidation inhibitors and are more potent antioxidants than steroids which have been shown to suppress tumor proliferation. The effects of two lazaroid compounds (U-75389G and U-83836E) were tested on the proliferation of a human brain astrocytoma cell line U-373MG. Both lazaroids had dose-dependent growth-inhibitory effects on the proliferation of U-373MG. For purposes of comparison, two steroids (methylprednisolone and dexamethasone) and a highly potent antioxidant (alpha-tocopherol) were tested under similar experimental conditions and were found to have antiproliferative effects as well, although at higher dose ranges. As cell growth-inhibitors, lazaroids are more effective than alpha-tocopherol while they are advantageous over glucocorticoids for their actions are devoid of the usual glucocorticoid side-effects.


Assuntos
Antineoplásicos/toxicidade , Antioxidantes/toxicidade , Divisão Celular/efeitos dos fármacos , Cromanos/toxicidade , Piperazinas/toxicidade , Esteroides/toxicidade , Astrocitoma , Neoplasias Encefálicas , Linhagem Celular , Relação Dose-Resposta a Droga , Glucocorticoides/toxicidade , Humanos , Cinética , Células Tumorais Cultivadas
20.
Neurosurgery ; 37(5): 937-46; discussion 946-7, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8559343

RESUMO

We have previously reported that calcium channel antagonists can block both the growth of meningiomas in culture and the potent growth stimulation of meningioma cells by epidermal growth factor (EGF) and platelet-derived growth factor (PDGF). This study further defines the nature of this growth inhibition. Primary meningioma cultures were established, and cells were characterized. Fibroblast growth factor or insulin-like growth factor-I growth stimulation in the presence of calcium channel antagonists was examined. In addition, the effects of ethylene glycol-bis-(aminoethylether) N,N,N',N"-tetraacetic acid and Bay K 8644, a calcium channel agonist, on the growth factors were analyzed. Growth factor receptor immunohistochemistry was performed on the original tumors and the in vitro meningioma cells. Twelve of 17 (71%) meningiomas in this study were positive for the EGF receptor, and 14 of 17 (82%) were positive for the PDGF receptor. Five of six (83%) of the culture cells were positive for the EGF receptor, and four of five (80%) were positive for the PDGF receptor. Intracellular calcium changes were quantified using the intracellular calcium-chelating, fluorescent dye, Fura-2. The growth stimulation of fibroblast growth factor and insulin-like growth factor-I on meningioma cells in culture was decreased in a dose-dependent manner by calcium channel antagonists. The growth stimulation of fibroblast growth factor and insulin-like growth factor-I was not affected by a reduction of extracellular calcium, whereas the growth stimulation of EGF and PDGF was. Interestingly, intracellular calcium was not increased after exposure to growth factors but was increased after serum stimulation. This increase could be blocked by preincubation with verapamil. Calcium channel antagonists can inhibit proliferation of meningioma cells in culture after stimulation with a number of growth factors. These drugs might disrupt intracellular calcium homeostasis or interfere with key elements of the growth factor signal transduction pathways. These mechanisms as well as the potential clinical relevance of these findings are discussed.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Divisão Celular/efeitos dos fármacos , Substâncias de Crescimento/farmacologia , Neoplasias Meníngeas/patologia , Meningioma/patologia , Receptores de Fatores de Crescimento/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos , Adulto , Idoso , Divisão Celular/fisiologia , Fator de Crescimento Epidérmico/farmacologia , Feminino , Fatores de Crescimento de Fibroblastos/farmacologia , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/fisiologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptores de Fatores de Crescimento/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas/patologia
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