Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Pediatr Endocrinol Metab ; 19 Suppl 1: 381-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16700314

RESUMO

The transsphenoidal approach has specific indications in the management of craniopharyngiomas. Usually, it is best reserved for patients with preferably cystic extra-arachnoid-infradiaphragmatic tumors with small suprasellar extension. Moreover, it is definitely less traumatic than transcranial approaches and it has been proven to be feasible also in paediatric patients. When possible, radical removal of these tumours must be the goal of surgery, but this attitude, which reduces but not eliminates the risk of relapse, has to be counterbalanced by heavy morbidity and even mortality, especially in children. In this view, many neurosurgeons favour a more 'conservative' approach with subtotal removal followed by radiotherapy whose dramatic efficacy on craniopharyngiomas is well known. With these premises, a transsphenoidal approach is realistically applicable to a greater number of large cystic craniopharyngiomas if the aim is not radical removal, but is to drain them into the sphenoid sinus to relieve mass effect symptoms (cystosphenoidostomy), and delay radiotherapy and its detrimental effects on visual and pituitary function, especially in younger patients, to a more suitable time after surgery.


Assuntos
Craniofaringioma/cirurgia , Procedimentos Neurocirúrgicos , Neoplasias Hipofisárias/cirurgia , Osso Esfenoide , Atividades Cotidianas , Adolescente , Criança , Feminino , Humanos , Masculino , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/mortalidade , Seio Esfenoidal/fisiologia , Resultado do Tratamento
2.
Med Biol Eng Comput ; 41(4): 481-5, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12892373

RESUMO

Ciliary beating and metachronal waves are fundamental to effective mucociliary transport. The ciliary beat frequencies (CBFs) and metachronal wave directions of multiple cilia beating in culture media were measured simultaneously using digital microscopic images. The degree of synchronisation between ciliary beats was determined by the correlation between ciliary signals at two different locations. The wave propagation directions of cilia were determined from a two-dimensional correlation map by a principal axis method. The standard deviation of measured wave directions in a region of interest was defined as a measure of metachronal wave disorder (MWD). Considerable variation was found in the beat frequencies and metachronal wave directions of cilia beating on epithelium. The pooled mean of MWDs was 23.4 +/- 8.8 degrees, and the pooled mean of CBFs was 10.1 +/- 1.9 Hz on 120 cells from five healthy subjects. The means of the MWD and the CBF from subjects were highly correlated (correlation = -0.83). The higher the CBF, the lower the level of the MWD.


Assuntos
Processamento de Imagem Assistida por Computador , Depuração Mucociliar , Seio Esfenoidal/fisiologia , Humanos , Microscopia de Vídeo , Mucosa/fisiologia
3.
Eur Arch Otorhinolaryngol ; 255(3): 135-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9561860

RESUMO

In vitro studies of human ciliary activity require relatively large quantities of specimens of healthy ciliated epithelium. For this reason we investigated whether cryopreserved healthy mucosa taken from the sphenoid sinus during pituitary surgery would meet the demands of this type of study. The sinus mucosa from ten patients was immersed in two different cryopreservatives. One solution contained 10% dimethylsulfoxide (DMSO) as cryoprotector. The other contained glycerol as a part of human sperm preservation medium (HSPM). The ciliary beat frequency (CBF) was measured sequentially by a photoelectrical method: when specimens were fresh and then at intervals of 1 week, 1 month and 3 months after cryopreservation in liquid nitrogen and thawing. Mean CBF values recorded after thawing did not differ significantly from the values measured before cryopreservation. Prior to cryopreservation and after thawing, CBF did not change during a period of 4 h. Epithelia preserved in DMSO demonstrated that the low mean CBF (5.4 Hz) found was caused by a reversible ciliostatic effect of the medium. After thawing and rinsing with a neutral medium, CBF showed normal values. We conclude that sphenoid sinus mucosa is an appropriate source of ciliated mucosa for in vitro experiments. Since non-pathological ciliated epithelium can be maintained in a "mucosa bank," our finding makes further studies of CBF of normal human respiratory epithelium in vitro a realistic goal.


Assuntos
Cílios/fisiologia , Criopreservação , Seio Esfenoidal/fisiologia , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Glicerol/farmacologia , Humanos , Técnicas In Vitro , Mucosa/fisiologia
4.
An Otorrinolaringol Ibero Am ; 24(2): 169-86, 1997.
Artigo em Espanhol | MEDLINE | ID: mdl-9199113

RESUMO

Thanks to the help of anatomical dissections and imaging techniques we way present this paper in which are described the morphologic characteristics of the sinus, its pneumatization types more frequently encountered, the traits more noteworthy related to the intersinusal partition and bone crests inside the sinus as well the distances detaching the sinus from the anterior wall of the sella turcica and clivus, through which wall the sinus cavity keeps in touch with noble cranial structures as the hypophysis and the brain stem. Ultimately our outcomes are compared with those given by other researchers.


Assuntos
Seio Esfenoidal/anatomia & histologia , Seio Esfenoidal/fisiologia , Humanos
5.
An Otorrinolaringol Ibero Am ; 24(2): 187-95, 1997.
Artigo em Espanhol | MEDLINE | ID: mdl-9199114

RESUMO

In this paper are exposed the main characteristics of the sphenoidal sinus rise, through a follow-up of its growth during the life-span of the first 20 years of life. For so doing the AA. studied the antero-posterior diameters, the vertical greatest diameter and the several distances detaching this sinus from other important anatomical references, as well the various degrees of pneumatization that the cavity may reach according as the years go over.


Assuntos
Seio Esfenoidal/anatomia & histologia , Seio Esfenoidal/fisiologia , Adolescente , Adulto , Pré-Escolar , Seguimentos , Humanos , Lactente
7.
Laryngoscope ; 102(4): 451-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1556898

RESUMO

This investigation's aim was to study a noninvasive method for determining the ventilation of the nasal sinuses. For this purpose, different insufflation techniques using xenon 133 were tried, along with different scintillation camera techniques. Xenon 133 gas was used for insufflation in the nose and sinuses, and the half-time of the washout curves was determined with the aid of digital scintillation cameras, one of which was capable of dynamic tomography. The tomographic procedure was superior because it made it possible to study the washout from the ethmoidal/sphenoidal sinuses as well. The washout was followed for up to 150 minutes. Great variations in washout were found between different sinuses and also in the same sinus over time. The single photon emission computed tomography (SPECT) technique, which is easy to perform and gives a limited absorbed dose to the patient, seems promising for the future evaluation of sinus ventilation and ostial function.


Assuntos
Seios Paranasais/diagnóstico por imagem , Seios Paranasais/fisiologia , Respiração/fisiologia , Tomografia Computadorizada de Emissão de Fóton Único , Absorção , Adulto , Seio Etmoidal/diagnóstico por imagem , Seio Etmoidal/fisiologia , Feminino , Seio Frontal/diagnóstico por imagem , Seio Frontal/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Insuflação , Masculino , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/fisiologia , Pessoa de Meia-Idade , Cavidade Nasal , Postura , Doses de Radiação , Seio Esfenoidal/diagnóstico por imagem , Seio Esfenoidal/fisiologia , Decúbito Dorsal , Radioisótopos de Xenônio
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...