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INTRODUCTION: Cisternal and ventricular blood predisposes to hydrocephalus and cerebral ischemia after high-grade aneurysmal subarachnoid hemorrhage (HGSAH). We studied the role of lamina terminalis fenestration combined with cisternal blood evacuation in HGSAH. PATIENTS/MATERIALS AND METHODS: A clinical, prospective, non-randomized study of a series of HGSAH patients (Modified Fisher>or=3) treated in the acute phase was carried out. The microsurgical treatment included aneurysm clipping, cisternal blood evacuation, and fenestration of the lamina terminalis. A comparable, non-blood-cleansed, endovascular-treated group, was included as a control. Clinical results were evaluated by the Glasgow Outcome Scale (GOS). RESULTS: During a period of 30 months, 95 patients who met the selection criteria were treated by microsurgical procedures and 28 by endovascular procedures. The distribution of GOS scores was superior for the microsurgical group: good results (GOS 4-5) were obtained in 85.3%, with a mortality rate of 5.9%. By contrast, 60.3% of patients in the endovascular group achieved GOS 4-5 scores, and 15.8% died. Good results for the endovascular group correlated inversely with delay of treatment. A permanent ventriculo-peritoneal shunt was necessary in 3.2% and 7.1% of the microsurgical and endovascular groups, respectively. The incidence of cerebral infarct was 3.1% and 14.3% for the microsurgical and endovascular groups, respectively. DISCUSSION: Microsurgical management reduces the usually poor outcome of patients with HGSAH. Lamina terminalis fenestration diminishes the incidence of shunt-dependent hydrocephalus and, combined with extensive cisternal blood cleansing, can lower the incidence of stroke. A procedure for cleansing blood and clots from the cisterns in HGSAH, based on the pathophysiology of vasospasm, is proposed.
Assuntos
Hipotálamo/cirurgia , Trombose Intracraniana/cirurgia , Microcirurgia/métodos , Hemorragia Subaracnóidea/cirurgia , Espaço Subaracnóideo/cirurgia , Ventriculostomia/métodos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/patologia , Artérias Cerebrais/fisiopatologia , Feminino , Humanos , Hidrocefalia/etiologia , Hipotálamo/anatomia & histologia , Hipotálamo/fisiologia , Trombose Intracraniana/etiologia , Trombose Intracraniana/fisiopatologia , Masculino , Estudos Prospectivos , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/fisiopatologia , Espaço Subaracnóideo/diagnóstico por imagem , Espaço Subaracnóideo/fisiopatologia , Terceiro Ventrículo/anatomia & histologia , Terceiro Ventrículo/fisiologia , Terceiro Ventrículo/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/prevenção & controle , Vasoespasmo Intracraniano/cirurgiaRESUMO
PURPOSE: To determine the predictability of different intraocular lens (IOL) power calculation formulas (SRK-II, Binkhorst-II, Hoffer Q, Holladay y SRK/T) according to the axial length (AL). METHOD: The residual refractive error for each formula was determined in 212 cases of phacoemulsification with IOL implantation and it was compared to the <
Assuntos
Implante de Lente Intraocular/estatística & dados numéricos , Facoemulsificação/métodos , Erros de Refração , Humanos , Implante de Lente Intraocular/métodosRESUMO
We study limit cycles of nonlinear oscillators described by the equation x + nuF(x) + x = 0 with F an odd function. Depending on the nonlinearity, this equation may exhibit one or more limit cycles. We show that limit cycles correspond to relative extrema of a certain functional. Analytical results in the limits nu-->0 and nu-->infinity are in agreement with previously known criteria. For intermediate nu, numerical determination of the limit cycles can be obtained.
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OBJECTIVE: Persistent primitive carotid-basilar artery anastomoses are uncommon, and are usually seen on an angiogram or discovered at autopsy. The most frequent type of anastomosis is the persistent trigeminal artery. METHODS: A single case of a medial variation of the persistent trigeminal artery, as seen in a well-preserved human adult anatomic specimen injected with red latex, is presented, and the anatomy of this uncommon anastomosis is discussed. RESULTS: This specimen is unique in its clear preservation of the artery, which arises from the medial portion of the right intracavernous carotid artery and gives rise to two branches, the inferior hypophyseal artery and the dorsal meningeal artery to the clivus. CONCLUSION: A new variation of the persistent trigeminal artery is described, which is important to support the possibility that more than one variety of carotid-basilar anastomosis exists in this region.
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Artérias Cerebrais/anormalidades , Gânglio Trigeminal/irrigação sanguínea , Artéria Basilar/anormalidades , Artérias Carótidas/anormalidades , Anormalidades Congênitas/patologia , Dissecação , HumanosRESUMO
Tympanoctomys barrerae, a desert specialist member of the family Octodontidae, until now thought to be conservative, and ancestral to South American hystricognath rodents, presents the highest diploid chromosome number (2n = 102) known in a mammal. Unexpectedly, its karyotype was found to be composed mainly of metacentric to sub-metacentric chromosomes. Mechanisms by which such a karyotype may have been derived are discussed.