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1.
Neurosurg Rev ; 43(3): 977-986, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31098790

RESUMO

Traumatic bifrontal contusions (TBC) form a recognised clinical entity among patients with traumatic brain injury (TBI). This study aims to systematically review current literature on demographics, management, and predictors of outcomes of patients with TBC. A multi-database literature search (PubMed, Cochrane, OVID Medline/Embase) was performed using PRISMA as a search strategy. Studies were selected by predefined selection criteria (PROSPERO: CRD42018055390), and risk of bias was assessed using an adapted form of ROBINS-I tool. Of the 275 studies yielded by the literature search, seven articles met the criteria for inclusion, all of which were level III evidence. Total cohort consisted of 468 patients; predominantly male (n = 5; 303/417 patients) with average age 44.3 years (range, 7-81). Falls (44.9%) and road traffic accidents (46.6%) were the commonest mechanisms of injury with an average presentation GCS of 9.2 (n = 3, 119 patients). GCS on admission of ≤ 13.1 and contusion volume at day 2 post-injury of ≥ 62.9cm3 were associated with increased risk of deterioration needing surgical interventions (n = 1, 7 patients). The majority of patients underwent surgery; the average GOS was 4, at an average follow-up duration of 11.7 months (n = 6, 356 patients). The currently available evidence on the management of TBC is scarce. Larger multicentre well-designed studies are needed to further delineate the factors behind acute deterioration, the effectiveness of management options. Once in place, this can be used to develop and test an algorithmic approach to management of TBC resulting in consistently improved outcomes.


Assuntos
Lesões Encefálicas Traumáticas/complicações , Contusões/epidemiologia , Contusões/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/cirurgia , Criança , Demografia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Acta Neurochir (Wien) ; 160(4): 793-800, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29188366

RESUMO

INTRODUCTION: The neutrophil-lymphocyte count ratio (NLCR) is an established prognostic marker for renal, lung and colorectal carcinomas and has been suggested to be predictive of histological grade and outcome in adult intracranial tumours. The purpose of this study was to determine whether a correlation of the pre-operative neutrophil count (NC) and NLCR with the final histological grade exists in paediatric intracranial tumours. METHODS: A retrospective analysis was undertaken at a single centre. Patients less than 18 years old at the time of surgery who underwent tumour-related procedures from 2006 to 2015 were included. Patients with recurrent tumours, previous bone marrow transplant and metastases were excluded. Pre-operative full blood counts (FBC), collected before the diagnosis of intracranial pathology and before administration of steroids, were matched with histological diagnosis for each patient. Post-operative FBC was also recorded, together with survival data where applicable. RESULTS: A total of 116 patients (74 male, 42 female; mean age, 8 ± 0.9 years) with a diagnosis of primary intracranial tumours had pre-operative FBC that could be matched to final histological grade. Pre-operative NC and NLCR were higher with increasing grade of tumour: grade 1 (NC 4.29 109/l, NLCR 2.26), grade 2 (NC 4.59 109/l, NLCR 2.38), grade 3 (NC 5.67 109/l, NLCR 2.72) and grade 4 (NC 6.59 109/l, NLCR 3.31). Patients with WHO grade 1 and 2 tumours pooled together had a lower NC (4.37 95% CI ± 0.67 109/l) compared to WHO grade 3 and 4 patients (6.41 95% CI ± 0.99 109/l, p = 0.0013). The NLCR was lower in grade 1 and 2 tumours (2.29 ± 0.59) (compared to grade 3 and 4 tumours; 3.20 ± 0.76) but this did not reach significance (p = 0.069). The subgroup of patients with pilocytic astrocytoma had a significantly lower NC when compared to patients with high-grade tumours (p = 0.005). Medulloblastoma and supratentorial PNET subgroups had significantly higher NC compared to the low-grade group (p = 0.033, p = 0.002). Post-operative NC was significantly higher in the high-grade tumours (p = 0.034), but no difference was observed for NLCR (p = 0.28). CONCLUSIONS: No evidence exists to support the correlation of pre-operative NC or NLCR to histological diagnosis in paediatric intracranial tumours. Our results indicate that a higher pre-operative NC/NLCR correlates with a higher histological grade of tumour. This suggests that immunological mechanisms may be involved in the pathogenesis of paediatric brain tumours, and a further prospective study is required to substantiate and expand these findings.


Assuntos
Astrocitoma/sangue , Neoplasias Encefálicas/sangue , Neoplasias Cerebelares/sangue , Meduloblastoma/sangue , Recidiva Local de Neoplasia/sangue , Adolescente , Astrocitoma/epidemiologia , Astrocitoma/patologia , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/patologia , Neoplasias Cerebelares/epidemiologia , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Feminino , Humanos , Contagem de Leucócitos , Masculino , Meduloblastoma/epidemiologia , Meduloblastoma/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia
4.
Br J Neurosurg ; 16(4): 370-2, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12389890

RESUMO

A case report of a patient who developed cauda equina syndrome following pelvic traction for acute sciatica is presented. A good outcome was obtained with prompt surgical decompression. This case illustrates the potential dangers of traction, which is frequently employed in the management of acute back pain.


Assuntos
Polirradiculopatia/etiologia , Ciática/terapia , Tração/efeitos adversos , Doença Aguda , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Polirradiculopatia/diagnóstico
5.
Cancer Genet Cytogenet ; 131(1): 1-12, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11734311

RESUMO

We describe the cytogenetic results of 58 pediatric central nervous system (CNS) tumors of variable histology, investigated between 1992 and 2000. Successful cytogenetics were obtained for 53 patients, with clonal chromosome abnormalities demonstrated in 25. Notable findings included (1) 2p abnormality in four primitive neuroectodermal tumors (PNET); (2) 1p loss in four low-grade gliomas and two PNET; (3) telomeric associations in one pilocytic astrocytoma; (4) chromosome 7 gain in four astrocytomas and two PNET; (5) 17p loss in four PNET; (6) double minutes in one PNET and three glioblastomas; and (7) chromosome 10 loss in four PNET. Higher grade tumors demonstrated greater karyotype complexity. Low-grade tumors showed either minimal simple chromosome changes or a normal karyotype. Chromosome abnormalities were more frequent in supratentorial tumors than their infratentorial counterparts. Our results add weight to the limited existing body of cytogenetic documentation for pediatric CNS tumors and provide further evidence that 2p loss is a consistent region of chromosome involvement in PNET. We advocate further studies of CNS tumors, in particular, to evaluate the importance of 2p changes and to compare cytogenetic results for supratentorial tumors and their infratentorial counterparts.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Criança , Cromossomos Humanos Par 2/genética , Feminino , Predisposição Genética para Doença , Humanos , Cariotipagem , Masculino , Metáfase/genética
6.
J Neurosurg ; 95(5): 791-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702869

RESUMO

OBJECT: The authors undertook a study to evaluate the effectiveness of endoscopic third ventriculostomy in the management of hydrocephalus before and after surgical intervention for posterior fossa tumors in children. METHODS: Between October 1, 1993, and December 31, 1997, a total of 206 consecutive children with posterior fossa tumors underwent surgery at Hjpital Necker-Enfants Malades in Paris. Excluded were 10 patients in whom shunts had been placed at the referring hospital. The medical records and neuroimaging studies of the remaining 196 patients were reviewed and categorized into three groups: Group A, 67 patients with hydrocephalus present on admission in whom endoscopic third ventriculostomy was performed prior to tumor removal; Group B, 82 patients with hydrocephalus who did not undergo preliminary third ventriculostomy but instead received conventional treatment; and Group C, 47 patients in whom no ventricular dilation was present on admission. There were no significant differences between patients in Group A or B with respect to the following variables: age at presentation, evidence of metastatic disease, extent of tumor resection, or follow-up duration. In patients in Group A, however, more severe hydrocephalus was demonstrated (p < 0.01): the patients in Group C were in this respect different from those in the other two groups. Ultimately, there were only four patients (6%) in Group A compared with 22 patients (26.8%) in Group B (p = 0.001) in whom progressive hydrocephalus required treatment following removal of the posterior fossa tumor. Sixteen patients (20%) in Group B underwent insertion of a ventriculoperitoneal shunt, which is similar to the incidence reported in the literature and significantly different from that demonstrated in Group A (p < 0.016). The other six patients (7.3%) were treated by endoscopic third ventriculostomy after tumor resection. In Group C, two patients (4.3%) with postoperative hydrocephalus underwent endoscopic third ventriculostomy. In three patients who required placement of CSF shunts several episodes of shunt malfunction occurred that were ultimately managed by endoscopic third ventriculostomy and definitive removal of the shunt. There were no deaths; however, there were four cases of transient morbidity associated with third ventriculostomy. CONCLUSIONS: Third ventriculostomy is feasible even in the presence of posterior fossa tumors (including brainstem tumors). When performed prior to posterior fossa surgery, it significantly reduces the incidence of postoperative hydrocephalus. The procedure provides a valid alternative to placement of a permanent shunt in cases in which hydrocephalus develops following posterior fossa surgery, and it may negate the need for the shunt in cases in which the shunt malfunctions. Furthermore, in patients in whom CSF has caused spread of the tumor at presentation, third ventriculostomy allows chemotherapy to be undertaken prior to tumor excision by controlling hydrocephalus. Although the authors acknowledge that the routine application of third ventriculostomy in selected patients results in a proportion of patients undergoing an "unnecessary" procedure, they believe that because patients' postoperative courses are less complicated and because the incidence of morbidity is low and the success rate is high in those patients with severe hydrocephalus that further investigation of this protocol is warranted.


Assuntos
Neoplasias Encefálicas/complicações , Endoscopia , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Terceiro Ventrículo/cirurgia , Ventriculostomia , Adolescente , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Fossa Craniana Posterior , Humanos , Hidrocefalia/prevenção & controle , Lactente , Complicações Pós-Operatórias
9.
Childs Nerv Syst ; 16(8): 493-5, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11007499

RESUMO

We describe the case of a child in whom proximal migration of the peritoneal catheter and extrusion of the ventricular catheter resulted in the entire ventriculo-peritoneal shunt along with the shunt chamber (Orbis Sigma II valve) lying in a sub-galeal pocket in the occipital region in a tightly coiled fashion. This coiling was very similar in appearance to that of the pre-insertion shunt in the packaging when it is supplied; hence it is postulated that the migration was secondary to retained 'memory' of the shunt tubing. This is a rare complication of ventriculo-peritoneal shunt, which has not been described before.


Assuntos
Migração de Corpo Estranho/diagnóstico , Hidrocefalia/cirurgia , Complicações Pós-Operatórias/diagnóstico , Derivação Ventriculoperitoneal/efeitos adversos , Humanos , Recém-Nascido , Masculino , Lobo Occipital/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Derivação Ventriculoperitoneal/métodos
10.
Can J Neurol Sci ; 26(1): 40-3, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10068806

RESUMO

OBJECTIVE: One of the difficulties with lumboperitoneal (LP) shunts has been non-invasively ascertaining shunt function. It has been previously reported that in the presence of a functioning LP shunt the perimesencephalic cisterns become obliterated--the "absent cistern sign". In order to more rigorously test this association we performed a retrospective analysis of LP shunt patients at the Hospital for Sick Children, Toronto. METHODS: The CT scans of all patients undergoing LP shunting over a 17 year period were reviewed. The "absent cistern sign" and ventricular size were compared against the results of either an isotope shunt study or surgical findings performed within 2 days of the CT. RESULTS: There were 38 CT scans (27 patients) performed within 2 days of an isotope shunt study and 15 CT scans (14 patients) performed within 2 days of a surgical intervention. These results give the absent cistern sign a sensitivity of 75% and a specificity of 57% when compared to the shunt isotope findings and a sensitivity of 100% and a specificity of 50% when compared to the surgical findings. Over 30% of the CT scans showed ventriculomegaly in the presence of a functioning shunt and, conversely, nearly 45% of the CT scans had normal or small lateral ventricles in the presence of a malfunctioning shunt. CONCLUSIONS: The "absent cistern sign" appears to reliably rule out a completely blocked shunt, but is less reliable in detecting a normal or partially obstructed shunt. Ventricular size correlates poorly with LP shunt function.


Assuntos
Derivações do Líquido Cefalorraquidiano , Mesencéfalo/diagnóstico por imagem , Adolescente , Ventriculografia Cerebral , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Cavidade Peritoneal/fisiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
J Neurosurg ; 86(2): 177-81, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9010415

RESUMO

Cases of craniosynostosis usually fall into well-demarcated categories: those related to a syndrome or those identified by a combination of suture involvement and morphological appearance. Between 1976 and 1995, 53 (3.6%) of 1474 cases in the craniofacial databank were assessed and designated as nonsyndromic but unclassifiable. The records and radiological studies obtained in these patients were retrospectively analyzed and comparisons were made with patients classified in the databank as having simple craniosynostoses. It proved possible to divide the formerly unclassifiable cases into two groups: those with "two-suture disease" (Group A) and a "complex" group (Group B) in which more than two sutures were affected. Group A consisted of 36 cases (68%) of patients presenting with clear evidence of simultaneous involvement of two sutures but with no progression over time to suggest a more diffuse pansynostosis. Suture involvement was as follows: 17 of 36 sagittal plus one coronal; seven of 36 sagittal and metopic; six of 36 sagittal plus one lambdoid; and six of 36 metopic plus one coronal. The only significant difference between the Group A cases and the cases of simple craniosynostoses was in the percentage requiring a second operation (24% vs. 5%, p < 0.0001). Group B consisted of 17 cases in which the patients presented at a slightly earlier age (mean 1 year) with severe morphological changes and multiple suture involvement. At the time of surgery, six of 17 patients showed large areas of lacunae within the cranial vault, making craniectomy the only option. In Group B, 10 of 17 patients displayed bilateral lambdoid plus sagittal suture involvement resulting in marked occipital recession posteriorly, whereas anteriorly in six of these 10 patients there was a massive frontal bone associated with posteriorly located coronal sutures. In contrast, there were also four patients in Group B with bilateral coronal plus metopic involvement resulting in a small frontal bone. There was a trend toward a lower intelligence quotient and a worse morphological outcome in the patients in Group B, but again the only result attaining statistical significance when compared to the databank was the rate of second operation (37.5 vs. 5%, p < 0.0001). "Two-suture synostosis" is a relatively straightforward condition and is treatable with standard craniosynostosis techniques. However, possibly as a result of surgical compromise when two sutures are involved, the rate of reoperation is far higher than in simple suture cases. In contrast, patients in the "complex" group presenting with severe multisuture involvement require a more tailor-made approach to their management that often entails a second procedure.


Assuntos
Craniossinostoses/classificação , Análise de Variância , Criança , Pré-Escolar , Craniossinostoses/fisiopatologia , Craniossinostoses/cirurgia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Testes de Inteligência , Pressão Intracraniana , Masculino , Monitorização Fisiológica , Reoperação
12.
Cerebrovasc Brain Metab Rev ; 8(2): 159-93, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8727185

RESUMO

Brain damage due to an episode of cerebral hypoxia/ischemia remains a major problem in the human infant, providing impetus for the testing of potential neuroprotective agents in animal models. Although these animal models do not mirror the human pathology exactly (e.g., with respect to regions vulnerable to damage), they usually have the histological characteristics of gray matter hypoxic/ischemic injury in the human. An important factor in comparing models directly is the stage of development of the brain at birth, which varies widely between species. Approaches to prevent or treat cerebral hypoxic/ischemic damage in neonates have paralleled those in adults. However, most of these results should be interpreted cautiously, since neonatal rat models with little concurrent physiological monitoring are often used. As in adults, moderate hypothermia during the insult or a preconditioning stress prior to the insult has prevented hypoxic/ ischemic brain damage. Different from adults is the demonstration that pretreatment with moderate doses of glucocorticoids or hyperglycemia during the hypoxic/ ischemic insult protects the brain against infarction. Partial protection, primarily in neonatal rats, has also been produced by pretreatment with voltage-sensitive calcium channel antagonists, free radical scavengers, growth factors, gangliosides, anticonvulsants, antiinflammatory agents, and nitric oxide synthase inhibitors. Posttreatment has been effective with a few agents. The most consistent has been the protective effect observed with glutamate receptor antagonists administered before but also up to 4 h after the insult. The effects of most of these therapies on blood glucose, body temperature, and/or the systemic circulation should be measured and the protective effects confirmed in larger species prior to considering clinical applications.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Hipóxia Encefálica/tratamento farmacológico , Hipóxia Encefálica/patologia , Adulto , Animais , Humanos , Recém-Nascido , Ratos
13.
J Cereb Blood Flow Metab ; 15(6): 1057-65, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7593338

RESUMO

The extent to which the reduction in CBF occurring in hydrocephalus is a primary or secondary event in the pathogenesis of the brain injury that ensues has not been clearly established. This is particularly true in neonatal hydrocephalus, where the disorder is most common, and where timing of the treatment of the developing nervous system is so important. We investigated the changes in local CBF (lCBF) in an animal model of severe progressive neonatal hydrocephalus before and after CSF shunting. Hydrocephalus was induced in 27 1-week-old kittens by percutaneous injection of 0.05 ml of 25% kaolin into the cisterna magna. Fourteen littermates acted as controls. The lCBF was measured by 14C-iodoantipyrine quantitative autoradiography after 1 week in 15 animals (8 hydrocephalic, 7 controls) and after 3 weeks in 26 animals (19 hydrocephalic, 7 controls) following induction of hydrocephalus. Twelve of the 3-week hydrocephalic group received a ventriculoperitoneal shunt 10 days following kaolin injection. At 1 week following induction of hydrocephalus, lCBF was globally reduced in cortical gray matter and white matter as well as deep subcortical structures. The maximum reduction was in the parietal white matter, to 37% of control levels. At 3 weeks a significant reduction in lCBF persisted only in the white matter (parietal, occipital, and corpus callosum; average, 42% of control levels), whereas cortical gray and deep subcortical structures had returned to normal levels spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ventrículos Cerebrais/irrigação sanguínea , Derivações do Líquido Cefalorraquidiano , Circulação Cerebrovascular , Hidrocefalia/fisiopatologia , Animais , Animais Recém-Nascidos , Autorradiografia , Gatos
14.
Exp Neurol ; 132(1): 116-22, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7720820

RESUMO

Pretreatment with the synthetic glucocorticoid dexamethasone prevents hypoxic-ischemic brain damage in 7-day-old neonatal rats. We presently characterize the response further by examining the effect of varying the age, the glucocorticoid, and the time of injection and by examining whether fasting can influence the response. Rats (n = 193) were randomized to one of 16 different treatment groups and subjected to hypoxia-ischemia (right carotid artery occlusion +8% O2 which was 3 h in duration for 7-day, 1 h for 2-week, and 30 min for 1-month-old animals). The brains were subsequently perfusion fixed and the area of infarction was measured from hematoxylin- and eosin-stained sections. Time dependence studies demonstrated that treatment with 0.1 mg/kg intraperitoneal dexamethasone 4 h prior to hypoxia reduced infarct size compared to vehicle-treated animals whereas pretreatment at either 48 h or 4 days was ineffective. Dexamethasone pretreatment (4 h) also provided neuroprotection against 4 h of hypoxia-ischemia. Fasted animals which received dexamethasone had reduced blood glucose levels yet markedly less damage than controls. Another glucocorticoid, methylprednisolone (0.7 mg/kg), also reduced infarction. In 2-week-old animals the area of infarction was reduced by pretreatment with dexamethasone, whereas in 1-month-old animals dexamethasone was ineffective. The results suggest that a glucocorticoid-mediated response intervenes in events leading to neuronal death in young animals but not older animals once myelination and synaptogenesis are complete.


Assuntos
Envelhecimento , Encefalopatias/prevenção & controle , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Dexametasona/uso terapêutico , Jejum , Hipóxia Encefálica/fisiopatologia , Hipóxia Encefálica/terapia , Fármacos Neuroprotetores/uso terapêutico , Animais , Encefalopatias/fisiopatologia , Isquemia Encefálica/patologia , Hipóxia Encefálica/patologia , Ratos , Fatores de Tempo
15.
J Neurosurg ; 80(3): 491-501, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8113862

RESUMO

The metabolic changes in neonatal hydrocephalus that lead to permanent brain injury are not clearly defined, nor is the extent to which these changes can be prevented by a cerebrospinal fluid shunt. To clarify these processes, cerebral glucose utilization was examined using [14C]2-deoxyglucose autoradiography in 1-month-old kittens, kaolin-induced hydrocephalic littermates, and hydrocephalic kittens in which a ventriculoperitoneal shunt had been inserted 10 days after kaolin injection. The hydrocephalic kittens showed thinning of the cerebral mantle and an anterior-to-posterior gradient of enlargement of the ventricular system, with a ventricle:brain ratio of 24% for the frontal and 35% for the occipital horns compared with control (< 0.5%) and shunted (< 5%) animals. White matter in hydrocephalic animals was edematous. Myelination was delayed in the periventricular region and in the cores of the cerebral gyri. Glucose utilization in hydrocephalic and shunted animals was unchanged from control animals in all gray-matter regions examined. However, in hydrocephalic animals, the frontal white matter exhibited a significant increase in glucose utilization (25 mumol.100 gm-1.min-1) in the cores of gyri compared with normal surrounding white-matter values (14.8 mumol.100 gm-1.min-1). Very low values (mean 4 mumol.100 gm-1.min-1) were found in areas corresponding to severe white-matter edema, and these areas were surrounded by a halo of increased activity (24 mumol.100 gm-1.min-1). In contrast, cytochrome oxidase activity in white matter was homogeneous. Shunting resulted in restoration of the cerebral mantle thickness, a return to normal levels of glucose utilization in the white matter, and an improvement in myelination. It is suggested that the areas of increased glucose utilization seen in the white matter represent anaerobic glycolysis which, if untreated, progresses to infarction. The pattern of this increased glucose utilization matches that of expected myelination and, during this period of high energy demand, white matter may be susceptible to the hypoperfusion associated with hydrocephalus.


Assuntos
Encéfalo/metabolismo , Glicólise , Hidrocefalia/metabolismo , Anaerobiose , Animais , Animais Recém-Nascidos , Gatos , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hidrocefalia/patologia
16.
J Neurosurg ; 79(3): 414-20, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8360739

RESUMO

It has recently been reported that pretreatment with a single dose of dexamethasone (0.1 mg/kg) 24 hours before hypoxia in 7-day-old rat pups is protective against an hypoxic-ischemic insult (unilateral carotid artery occlusion followed by 3 hours of hypoxia in 8% O2). The authors now examine whether pretreatment 6 hours before insult is equally effective and compare other agents potentially suitable for prophylaxis in neonatal hypoxia-ischemia, including the calcium antagonists flunarizine (30 mg/kg pretreatment), nimodipine (0.5 mg/kg pretreatment), and the 21-aminosteroid U-74389F (10 mg/kg pre- and posttreatment). For each active agent, there was also a vehicle-treated control group. Comparison of the mean area of ipsilateral infarction on brain coronal sections showed that there was no statistically significant difference between the various control groups (mean area of infarction 66% +/- 4%). Pretreatment with dexamethasone 6 hours prior to hypoxia offered complete protection with no infarction. A beneficial effect was seen following pretreatment with flunarizine (mean area of infarction 33.6% +/- 7.8%), although this degree of damage was still significantly different from that seen with dexamethasone pretreatment. Pretreatment with nimodipine or U-74389F offered no protection (mean area of infarction 77.5% +/- 4% and 59% +/- 10%, respectively). Unlike findings in adult animals and clinical studies, the current studies show that dexamethasone may have a role in the treatment of neonatal hypoxia-ischemia and deserves reappraisal.


Assuntos
Isquemia Encefálica/patologia , Bloqueadores dos Canais de Cálcio/farmacologia , Dexametasona/farmacologia , Hipóxia/patologia , Pregnatrienos/farmacologia , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Ratos , Ratos Sprague-Dawley
17.
J Neurosurg ; 78(4): 568-73, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8450330

RESUMO

Although the development of tonsillar herniation (acquired Chiari malformation) in association with lumboperitoneal (LP) shunting is well recognized, it has previously been considered rare. In order to ascertain the incidence of this complication after LP shunting, the authors undertook a retrospective study of all patients in whom this form of shunt had been inserted between 1974 and 1991 at The Hospital for Sick Children, Toronto. In the 143 patients, the mean age at insertion was 3.3 years and the indications for shunt placement were hydrocephalus (81%), pseudotumor cerebri (7%), cerebrospinal fluid fistula (6%), and posterior fossa pseudomeningocele (6%). The mean follow-up period was 5.7 years, during which time there was one shunt-related death due to unsuspected tonsillar herniation. Five other patients developed symptomatic tonsillar herniation treated by suboccipital decompression. Review of all computerized tomography (CT) scans not degraded by artifact showed evidence of excess soft tissue at the level of the foramen magnum in 38 (70%) of 54 patients so studied. In order to confirm that this CT finding represented hindbrain herniation, sagittal and axial magnetic resonance (MR) images were obtained for 17 asymptomatic patients and revealed tonsillar herniation (range 2 to 21 mm) in 12 (70.6%). In addition, some of these asymptomatic patients had evidence of uncal herniation and mesencephalic distortion. Similarities and distinctions are drawn between the morphological changes occurring after LP shunting and those seen in association with the Chiari I and II malformations. Although less than 5% of this study population required treatment for tonsillar herniation, the incidence of this complication was high in asymptomatic patients; MR imaging surveillance for patients with LP shunts is therefore recommended.


Assuntos
Doenças Cerebelares/etiologia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Adolescente , Malformação de Arnold-Chiari/diagnóstico , Doenças Cerebelares/diagnóstico , Derivações do Líquido Cefalorraquidiano/métodos , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Hérnia/diagnóstico , Hérnia/etiologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Cavidade Peritoneal , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
18.
Neurosurgery ; 32(3): 376-83; discussion 383, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8455762

RESUMO

There is a shortage of data concerning the long-term follow-up of patients with lumboperitoneal (LP) shunts, especially in the pediatric population. A retrospective study of 143 patients who underwent LP shunting between 1974 and 1991 was therefore performed. The mean age at the time of shunt insertion was 3.3 years (range, 18 d to 17.8 yr), and the indication for shunting was: hydrocephalus (81%), cerebrospinal fluid fistula (12%), and pseudotumor cerebri (7%). The mean follow-up time was 5.7 years (range, 5 d to 17.5 yr), and during this period, there were five deaths of which one was shunt related (2.5 yr post-shunt insertion). Of the types of LP shunt used during the study period, the T-tube shunt (101 patients) fared significantly better (P = 0.003) than the percutaneous type (42 patients), and the overall survival characteristics for the T-tube shunt approximated those seen for ventriculoperitoneal shunts, with a 50% probability of remaining free of malfunctions for 5 years. A high rate of migration (19%) was partially responsible for the poor performance of the percutaneous-type shunts. By the end of the study, 40 patients (28%) had been converted to ventricular shunts, and this rate of conversion was similar for both shunt types. LP shunts have certain advantages over other forms of cerebrospinal fluid diversion and were successfully used for various clinical conditions during this study.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Derivações do Líquido Cefalorraquidiano/instrumentação , Líquido Cefalorraquidiano , Fístula/cirurgia , Hidrocefalia/cirurgia , Pseudotumor Cerebral/cirurgia , Análise Atuarial , Adolescente , Criança , Pré-Escolar , Falha de Equipamento , Feminino , Fístula/etiologia , Seguimentos , Humanos , Hidrocefalia/etiologia , Lactente , Recém-Nascido , Masculino , Peritônio , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Pseudotumor Cerebral/etiologia , Reoperação , Estudos Retrospectivos , Derivação Ventriculoperitoneal/instrumentação
19.
Br J Neurosurg ; 6(6): 595-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1472327

RESUMO

A 2.5-year-old girl with Crouzon's disease, hydrocephalus, and a lumboperitoneal shunt died as a result of chronic tonsillar herniation (acquired Chiari 'malformation'). The possible synergistic role of the cranial dysmorphism and the lumboperitoneal shunt in the development of this anomaly is discussed. The literature is reviewed and it is argued that if hydrocephalus occurs in infants in whom cephalocranial disproportion is likely to develop, then it is inadvisable to insert a lumboperitoneal shunt.


Assuntos
Doenças Cerebelares/complicações , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Disostose Craniofacial/complicações , Hidrocefalia/complicações , Feminino , Hérnia/complicações , Humanos , Hidrocefalia/cirurgia , Recém-Nascido , Peritônio , Reoperação , Punção Espinal/efeitos adversos
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