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PURPOSE: The aim of this study was to compare intrathecal 1% chloroprocaine with 2% hyperbaric prilocaine in the setting of ambulatory knee arthroscopy. We hypothesized that complete resolution of the sensory block was faster with chloroprocaine. METHODS: Eighty patients scheduled for knee arthroscopy were included in this prospective randomized double-blind study. Spinal anesthesia was performed with either chloroprocaine (50 mg) or hyperbaric prilocaine (50 mg). Characteristics of sensory and motor blocks and side effects were recorded. RESULTS: Mean time to full sensory block recovery was shorter with chloroprocaine (169 (56.1) min vs 248 (59.4)). The characteristics of the sensory blocks were similar at the T12 dermatome level between the two groups. Differences appeared at T10: the percentage of patients with a sensory block was higher, onset quicker and duration longer with hyperbaric prilocaine. The number of patients with a sensory block at T4 dermatome level in both groups was minimal. Times to full motor recovery were identical in both groups (85 (70-99) vs 86 (76-111) min). Time to spontaneous voiding was shorter with chloroprocaine (203 (57.6) min vs 287.3 (47.2) min). Incidence of side effects was low in both groups. CONCLUSIONS: When considering the characteristics of the sensory block, the use of chloroprocaine may allow an earlier discharge of patients. Cephalic extension was to a higher dermatomal level and the sensory block at T10 level was of prolonged duration with hyperbaric prilocaine, suggesting that the choice between the two drugs should also be performed based on the level of the sensory block requested by the surgery. This study is registered in the US National Clinical Trials Registry, registration number: NCT030389 , the first of February 2017, Retrospectively registered.
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Rivers are known to be major contributors to eutrophication in marine coastal waters, but little is known on the short-term impact of freshwater surges on the structure and functioning of the marine plankton community. The effect of adding river water, reducing the salinity by 15 and 30%, on an autumn plankton community in a Mediterranean coastal lagoon (Thau Lagoon, France) was determined during a 6-day mesocosm experiment. Adding river water brought not only nutrients but also chlorophyceans that did not survive in the brackish mesocosm waters. The addition of water led to initial increases (days 1-2) in bacterial production as well as increases in the abundances of bacterioplankton and picoeukaryotes. After day 3, the increases were more significant for diatoms and dinoflagellates that were already present in the Thau Lagoon water (mainly Pseudo-nitzschia spp. group delicatissima and Prorocentrum triestinum) and other larger organisms (tintinnids, rotifers). At the same time, the abundances of bacterioplankton, cyanobacteria, and picoeukaryote fell, some nutrients (NH4+, SiO43-) returned to pre-input levels, and the plankton structure moved from a trophic food web based on secondary production to the accumulation of primary producers in the mesocosms with added river water. Our results also show that, after freshwater inputs, there is rapid emergence of plankton species that are potentially harmful to living organisms. This suggests that flash flood events may lead to sanitary issues, other than pathogens, in exploited marine areas.
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Carbono/química , Plancton , Ríos/química , Animales , Bacterias , Cadena Alimentaria , Francia , Agua Dulce , Rotíferos , SalinidadRESUMEN
Alpha-hemoglobin stabilizing protein (AHSP), described as a chaperone of alpha-hemoglobin (α-Hb), is synthesized at a high concentration in the erythroid precursors. AHSP specifically recognizes the G and H helices of α-Hb and forms a stable complex with free α-Hb until its association with the partner ß-subunits. Unlike the free ß-Hb which are soluble and form homologous tetramers, freshly synthesized α-Hb chains are highly unstable molecular species which precipitate and generate reactive oxygen species within the erythrocyte precursors of the bone marrow leading to apoptosis and ineffective erythropoiesis. AHSP protects the free α-Hb chains in maintaining it in the soluble state. In this review, we report data from the literature and our laboratory concerning the key role of AHSP in the biosynthesis of Hb and its possible involvement in some disorders of the red blood cell as well as the hemoglobinopathies and we discuss its use as a prognostic tool in thalassemia syndromes.
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Hemoglobinopatías/etiología , Hemoglobinas/biosíntesis , Chaperonas Moleculares/fisiología , Fragmentos de Péptidos/fisiología , Hemoglobinas/fisiología , HumanosRESUMEN
Ovarian hyperstimulation syndrome (OHSS) is usually a complication of assisted reproductive techniques, more rarely an affection complicating a spontaneous gestation. The cause of hyper responsiveness of ovaries to the gonadotropins used in the controlled stimulation is still largely unknown. In contrast, a few cases of spontaneous hyperstimulation syndrome have been elucidated by the identification of mutations of the follicle-stimulating hormone (FSH) receptor, broadening its specificity and making it hypersensitive to human chorionic gonadotropin (hCG). Surprisingly, the mutations were located in the transmembrane domain of the receptor rather than in the extracellular hormone-binding site. No such mutation has been found in iatrogenic cases. However, allelic variants of the FSH receptors have been associated with the response to FSH in stimulation procedures, as well as with the severity of OHSS when present.
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Mutación , Síndrome de Hiperestimulación Ovárica/genética , Receptores de HFE/genética , Gonadotropina Coriónica/fisiología , AMP Cíclico/fisiología , Femenino , Hormona Folículo Estimulante/fisiología , Variación Genética , HumanosRESUMEN
A host may be physically isolated in space and then may correspond to a geographical island, but it may also be separated from its local neighbours by hundreds of millions of years of evolutionary history, and may form in this case an evolutionarily distinct island. We test how this affects the assembly processes of the host's colonizers, this question being until now only invoked at the scale of physically distinct islands or patches. We studied the assembly of true bugs in crowns of oaks surrounded by phylogenetically more or less closely related trees. Despite the short distances (less than 150 m) between phylogenetically isolated and non-isolated trees, we found major differences between their Heteroptera faunas. We show that phylogenetically isolated trees support smaller numbers and fewer species of Heteroptera, an increasing proportion of phytophages and a decreasing proportion of omnivores, and proportionally more non-host-specialists. These differences were not due to changes in the nutritional quality of the trees, i.e. species sorting, which we accounted for. Comparison with predictions from meta-community theories suggests that the assembly of local Heteroptera communities may be strongly driven by independent metapopulation processes at the level of the individual species. We conclude that the assembly of communities on hosts separated from their neighbours by long periods of evolutionary history is qualitatively and quantitatively different from that on hosts established surrounded by closely related trees. Potentially, the biotic selection pressure on a host might thus change with the evolutionary proximity of the surrounding hosts.
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Biodiversidad , Evolución Biológica , Heterópteros/fisiología , Interacciones Huésped-Parásitos/fisiología , Filogenia , Quercus/parasitología , Animales , Cadena Alimentaria , Francia , Heterópteros/genética , Especificidad de la EspecieRESUMEN
Manipulations of mouse genome have helped to elucidate gonadotrophin function but important differences subsist between rodent and human reproduction. Studies of patients with mutations of gonadotrophins or gonadotrophin receptors genes allow understanding their physiological effects in humans. The correlation of the clinical phenotypes of patients with in vitro studies of the mutated receptor residual function and histological and immunohistological studies of the ovarian biopsies permits to understand which stages of follicular development are under FSH control. Total FSH receptor (FSHR) inactivation causes infertility with an early block of follicular maturation remarkably associated with abundant small follicles as in prepubertal ovaries and demonstrates the absolute requirement of FSH for follicular development starting from the primary stage. Partial FSHR inactivation, characterized by normal-sized ovaries, can sustain follicular development up to the early antral stages but incremental levels of FSH stimulation seem to be required for antral follicular growth before selection. These findings contrast with the traditional view of an initial gonadotrophin-independent follicular growth prior to the preantral-early antral stages. The presence of numerous reserve follicles in the ovaries of these patients may permit a future treatment of their infertility. The study of reduced FSHbeta or FSHR activity in genetically modified male mice models and in men suggests a minor impact of the FSHR on masculine fertility. Further studies on patients with a demonstrated total FSHbeta or FSHR inactivation are required to elucidate reported differences in spermatogenesis impairment. Finally, the studies of mutations of gonadotrophins and their receptors demonstrate differences in gonadotrophin function between genetically modified rodents and humans which suggest prudence in extrapolating observations in rodents to human reproduction. Ovarian hyperstimulation syndrome (OHSS) can infrequently arise spontaneously during pregnancy, but most often it is an iatrogenic complication of ovarian stimulation treatments with ovulation drugs for in vitro fertilization. The first genetic cause of familial recurrent spontaneous OHSS was identified as a broadening specificity of the FSHR for hCG due to naturally occurring heterozygous mutations located unexpectedly in the transmembrane domain of the FSHR. Broadening specificity of a G protein-coupled receptor is extremely rare. These observations led to the identification of the etiology of this previously unexplained syndrome and permitted to conceive novel models of FSHR activation. Susceptibility to iatrogenic OHSS or its clinical severity may be associated with FSHR polymorphisms with slightly different activities in vivo as suggested by several studies. The study of larger cohorts is needed to evaluate the clinical impact of these observations in the management of patients undergoing IVF protocols.
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Mutación/genética , Receptores de HFE/genética , Receptores de HFE/fisiología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Infertilidad Femenina/genética , Infertilidad Masculina/genética , Masculino , Ratones , Síndrome de Hiperestimulación Ovárica/genética , LinajeRESUMEN
A new improving method to compute Spearman rank correlation test has been developed. This method is based on the use of a response to stimulation delay referred by many authors. Visual results tend to prove the method efficiency which is confirmed by obtained overlap rates; moreover this method can easily be adapted in a clinical context.
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Mapeo Encefálico/métodos , Interpretación Estadística de Datos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Estadísticas no Paramétricas , Técnica de Sustracción , Adulto , Algoritmos , Simulación por Computador , Femenino , Humanos , Masculino , Modelos Neurológicos , Modelos Estadísticos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
PURPOSE OF THE STUDY: The purpose of this study was to analyse the advantages, disadvantages and results of bilateral breast reconstruction by autologous latissimus dorsi flap. MATERIAL AND METHOD: Thirty-one two-stage consecutive bilateral breast reconstructions were performed by the same operator between 1993 and 2001. All the reconstructions, in immediate or delayed manner, were indicated after radical or skin sparing mastectomy for breast cancer. We used the autologous latissimus dorsi flap for all cases. The reconstruction of the second breast was always delayed of a few months to avoid back's complications. We reviewed the charts of these patients retrospectively. Preoperative data, postoperative complications, dorsal seroma occurrence, morphological results and patient's satisfaction were evaluated. Median follow-up was 22 months. RESULTS: The results confirm the procedure's reliability. Comparative rates of postoperative complications are not significantly different between first and contralateral breast reconstruction. Functional after-effects of bilateral latissimus dorsi harvesting are moderate. The aesthetics results have been judged as very good in 84% of cases and good in 16%. The satisfaction rate of the patients is high: 90,3% are pleased, 6,5% are satisfied and 3,2% are moderately satisfied. CONCLUSION: The autologous latissimus dorsi flap allows a two-stage bilateral breast reconstruction. This procedure is not indicated for simultaneous bilateral breast reconstruction; it is the main drawback of this technique. So we believe that this procedure is an excellent alternative in all the indications of sequential bilateral breast reconstructions.
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Mamoplastia/métodos , Mastectomía Radical , Músculo Esquelético/trasplante , Colgajos Quirúrgicos , Adulto , Neoplasias de la Mama/cirugía , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
A new approach to compute z-score and Student's test in functional MRI has been developed. This approach tends to involve standard z-score and Student's test computation. This approach is based on the delay of the response compared to the stimulation introduced by many authors. The results obtained prove the methods efficiency; moreover these methods can be easily adapted in a clinical context. This paper presents the new computation and the validation.
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Mapeo Encefálico/métodos , Encéfalo/fisiología , Interpretación Estadística de Datos , Potenciales Evocados/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Tiempo de Reacción/fisiología , Algoritmos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
AIM: To measure ketonemia in a control population of pregnant women and in a population of women with gestational diabetes (GDM). To define a normal ketonemia threshold for the controls and to determine whether or not this value could play a role in the clinical management of women with GDM. METHOD: Fifty-six women with a normal OGTT and 49 women with GDM were included and monitored from the 25th to the 37th week of pregnancy. Control subjects agreed to perform glycaemia and ketonemia self-monitoring 3 times a day. In addition, women with GDM were asked to measure their postprandial glycaemia. Glycaemia and ketonemia measurements were performed using Optium meters. Subjects kept a 24-hour food record twice a week. RESULTS: The mean ketonemia was lower in the control group than in the GDM group (0.01+/-0.10 vs. 0.04+/-0.009 mmol/l; P<0.001). Ketonemia values measured before the midday meal and prior to the evening meal were lower for control subjects than for GDM patients (P=0.002 and P=0.005). Fasting ketonemia was unrelated to ketonuria in the GDM group, whereas there was a correlation in the control group (P=0.006). At least one chronic increase in ketonemia levels was observed in 47% of the women with GDM, compared with only 12% of controls. The lowest levels of evening glycaemia correlated with the highest levels of ketonemia; women with GDM reported lower food and carbohydrate intakes than controls (P<0.001). CONCLUSION: This work has enabled the establishment of ketonemia reference standards in non-diabetic pregnant women. If ketonemia does indeed indicate overly restrictive dietary behavior, this parameter could be employed for monitoring adherence to the nutritional recommendations for GDM.
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Diabetes Gestacional/sangre , Cuerpos Cetónicos/sangre , Embarazo/sangre , Adulto , Índice de Masa Corporal , Ingestión de Energía , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Monitoreo Fisiológico , Valores de ReferenciaRESUMEN
BACKGROUND: Mitochondrial biogenesis and bioenergetics play an important role in oocyte maturation and embryo development. We have investigated the relationship between defective mitochondrial biogenesis and the lack of oocyte maturity observed during IVF procedures with patients suffering from ovarian dystrophy and ovarian insufficiency. METHODS: We used real-time quantitative PCR to quantify mitochondrial DNA (mtDNA) in 116 oocytes obtained from 47 women undergoing the ICSI procedure. We compared the mtDNA content of oocytes from women with a normal ovarian profile with that of oocytes from women with ovarian dystrophy and ovarian insufficiency. RESULTS: We found an average of 256,000 +/- 213,000 mitochondrial genomes per cell. The mean mtDNA copy number was not significantly different in ovarian dystrophy compared with controls, but it was significantly lower in oocytes from women with ovarian insufficiency (100,000 +/- 99,000, P < 0.0001). CONCLUSIONS: Our results suggest that low mtDNA content is associated with the impaired oocyte quality observed in ovarian insufficiency.
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ADN Mitocondrial/metabolismo , Oocitos/metabolismo , Insuficiencia Ovárica Primaria/metabolismo , Estudios de Casos y Controles , Sistemas de Computación , Femenino , Dosificación de Gen , Genoma Humano , Humanos , Enfermedades del Ovario/metabolismo , Reacción en Cadena de la Polimerasa , Insuficiencia Ovárica Primaria/fisiopatología , Inyecciones de Esperma IntracitoplasmáticasRESUMEN
Healthcare monitoring applications requires the measurement and the analysis of multiple physiological data. In the field of biomedical research, these data are issued from different devices involving data centralization and synchronization difficulties. On the other hand, the analysis of the acquired data requires high level digital signal processing tools. In this paper we describe a real time toolkit for biomedical data acquisition, centralization, processing and visualization. This toolkit, composed of both hardware and software modules, allows users to model, test and perform all kind of digital signal processing algorithms for all kind of biomedical signals. These highly efficient hardware and software modules have been developed and tested especially for biomedical studies and used in a large number of clinical investigations. So, for developers, using such a toolkit will reduce the development time while increasing the application performances.
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A new approach of registration in multimodal imaging has been developed. Modalities involved are Digital Subtracted Angiography (DSA, 2D) and Magnetic Resonance Angiography (MRA, 3D). Our approach is an hybrid one, mixing feature and intensity based approaches. This approach is based on the extraction of a anatomical referential common to both MRA and DSA. The results obtained prove the methods efficiency in a clinical context. This paper present the validation methodology to make it possible the replacement of the localization DSA examination by the diagnosis one, thus avoiding supplementary costs, lost time and medical hazards for the patient and for the medical staff.
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Liposuction is a simple and elegant way to treat fatty excess; it has been even used for the treatment of lipomas and some gynecomasties. The goal of this article is to present 2 patients with an unusual complication of this use: the liposuction of a malignant tumor. The first patient consulted following the liposuction of a "gynecomasty", which was in fact a breast cancer. The second was treated by liposuction for an ankle "lipoma"; it proved to be a liposarcoma. In order to avoid liposuction and dissemination of a malignant tumor, the pre-operative investigations have to search clinical peculiarities evoking the diagnosis: an unilateral "gynecomasty", irregular, hard or painless, in a 50-years-old patient, must incite the surgeon to perform a classical excision, just as a recurrent "lipoma", deeply located, voluminous or quickly extensive, situated on the limbs or in the humeroscapular area. Paraclinic investigations may be indicated; doubtful cases must be right away rejected for liposuction, and treated by a surgical excision with strict safety margins and complete anatomopathologic examination of the lesion. Liposuction has become a very useful technique for the plastic surgeon; however, we must not forget, despite of its many advantages the risk for dissemination of an unknown malignant tumor. Every surgeon must keep it in mind and prefer a surgical removal in atypical cases.
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Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Ginecomastia/cirugía , Lipectomía/efectos adversos , Lipoma/cirugía , Músculo Esquelético/trasplante , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Diagnóstico Diferencial , Femenino , Humanos , Pierna , Masculino , Persona de Mediana Edad , Factores de RiesgoRESUMEN
BACKGROUND: There is increasing evidence that mitochondrial DNA (mtDNA) anomalies in sperm may lead to infertility. Point mutations, deletions and the presence of a specific mtDNA haplogroup have been associated with poor sperm quality, but little attention has been paid to the role of mtDNA content. METHODS: Using density gradient separation and swim-up methods, we selected motile sperm from 32 normal and 35 abnormal sperm samples. The mtDNA/beta-globin gene ratio was determined by real-time quantitative PCR. RESULTS: The average mtDNA/beta-globin ratio of sperm collected from 100% density layers was 1.4 for normal sperm, 6.1 for sperm samples presenting at least one abnormal criterion [among the three criteria established by World Health Organization (1999), i.e. sperm count, motility and morphology], and 9.1 for sperm samples presenting two or more of these abnormal criteria. These differences are very highly significant (P < 0.0001). The mtDNA numbers were also much greater in sperm collected from the 40% density gradient layers (mean: 17.1, P < 0.001), known to contain the most abnormal sperm of the sperm samples, than in those collected from the 100% layers known to contain sperm with the best fertilizing ability. CONCLUSION: Our results showed significant mtDNA amplification in sperm collected from abnormal sperm samples.
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ADN Mitocondrial/metabolismo , Infertilidad Masculina/genética , Espermatozoides/metabolismo , Sistemas de Computación , ADN Mitocondrial/fisiología , Globinas/metabolismo , Humanos , Infertilidad Masculina/metabolismo , Infertilidad Masculina/patología , Infertilidad Masculina/fisiopatología , Masculino , Reacción en Cadena de la Polimerasa , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Espermatozoides/citologíaRESUMEN
The most serious hazard of gestational diabetes is shoulder dystocia, which sometimes is complicated by Erb's palsy and maternal lacerations. This risk is linked to fetal weight, and is more frequent in cases of diabetes. So, a caesarean section performed when macrosomia is present is required and an induction of labor before severe macrosomia is proposed. Unfortunately, estimation of fetal weight is imprecise in spite of formulas from fetal parameters. Abdomen circumference (AC) alone is as effective as complex formulas. So, it is proposed to perform an elective section when AC is equal or above 38 cm, and to induce labor, after 38 weeks of gestation, for limiting the risk of macrosomia when AC is between 35 and 38 cm. Induction is also proposed when pregnancy is complicated by hypertension or when fetal heart septal hypertrophy occurs. The management of gestational diabetes means a strict control of glycemia, which can reduce macrosomia and the need for cesarean section or induction of labor.
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Diabetes Gestacional , Trabajo de Parto Inducido , Traumatismos del Nacimiento/etiología , Traumatismos del Nacimiento/prevención & control , Diabetes Gestacional/complicaciones , Distocia/etiología , Distocia/prevención & control , Femenino , Macrosomía Fetal/complicaciones , Edad Gestacional , Humanos , Embarazo , HombroRESUMEN
This study highlighted combinations of chemical stresses that could decrease or eliminate Listeria monocytogenes and Pseudomonas spp. surviving in food processing plants. Strains of L. monocytogenes, Pseudomonas fragi, and Pseudomonas fluorescens isolated from processing environments (meat and milk) were grown at 20 degrees C up to the early stationary phase. The strains were then subjected to 30 min of physicochemical treatments. These treatments included individual or combined acid (acetic acid), alkaline (NaOH), osmotic (NaCl), and biocides (fatty acids) challenges. Survival of the strains was studied after individual or combined acid (acetic acid), alkaline (NaOH), osmotic (NaCl), and biocides (monolaurin, lauric acid) challenges. Individual pH shocks had lower efficiencies than those used in combinations with other parameters. The treatment pH 5.4 followed by pH 10.5 had a low efficiency against L. monocytogenes. The opposite combination, pH 10.5 followed by pH 5.4, led to a 3-log reduction of the L. monocytogenes population. Pseudomonas spp. strains were much more sensitive than L. monocytogenes, and population reductions of 5 and 8 log (total destruction), respectively, were observed after the same treatments. As for L. monocytogenes, the combination pH 10.5 followed by pH 5.4 is more deleterious than the opposite. Whatever the bacterial species, the most efficient treatments were combinations of alkaline, osmotic, and biocide shocks. For instance, the combination pH 10.5 and 10% NaCl plus biocides showed reductions of 5 to 8 log for both bacteria. The origins of the observed lethal effects are discussed.
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Manipulación de Alimentos/métodos , Listeria monocytogenes/efectos de los fármacos , Pseudomonas/efectos de los fármacos , Cloruro de Sodio/farmacología , Hidróxido de Sodio/farmacología , Cáusticos , Sinergismo Farmacológico , Microbiología de Alimentos , Concentración de Iones de Hidrógeno , Listeria monocytogenes/crecimiento & desarrollo , Pseudomonas/crecimiento & desarrolloRESUMEN
PURPOSE: Treatment planning for radiosurgery depends on the precise definition of radiation target volumes. For vascular pathologies such as arteriovenous malformations (AVM), the most usual technique remains standard X-ray projection imaging, most often carried out under stereotactic conditions. To further benefit from the advantages of two-dimensional digital subtraction angiography (DSA), the authors have developed a method for determining the three-dimensional shape of arteriovenous malformations from two views. METHODS AND MATERIALS: After correction of image intensifier distortion and calibration of both views, the 3D shape of the AVM was determined from two DSA projections using epipolarity geometry. The AVM-encapsulating contour was modeled by triangulation of a stack of almost parallel ellipses. The method was technically validated using artificial targets in a skull phantom. Clinical validation was carried out on 10 patients who were examined using both conventional angiography under stereotactic conditions (SX-ray) and DSA. RESULTS: There was excellent agreement between the artificial target volumes measured with SX-ray and with DSA. The correspondence between AVM volumes found for patients was not as good as with the phantom. CONCLUSIONS: The different image characteristics of the two modalities lead to some differences in AVM estimations. However, the results were sufficiently satisfactory to justify routine use of this AVM modeling technique for radiosurgery planning.
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Angiografía de Substracción Digital/métodos , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/cirugía , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Humanos , Malformaciones Arteriovenosas Intracraneales/patología , Modelos Biológicos , Fantasmas de Imagen , Radiocirugia/instrumentación , Planificación de la Radioterapia Asistida por Computador/instrumentación , Reproducibilidad de los ResultadosRESUMEN
Techniques of three-dimensional (3-D) volume delineation from tomographic medical imaging are usually based on 2-D contour definition. For a given structure, several different contours can be obtained depending on the segmentation method used or the user's choice. The goal of this work is to develop a new method that reduces the inaccuracies generally observed. A minimum volume that is certain to be included in the volume concerned (membership degree mu = 1), and a maximum volume outside which no part of the volume is expected to be found (membership degree mu = 0), are defined semi-automatically. The intermediate fuzziness region (0 < mu < 1) is processed using the theory of possibility. The resulting fuzzy volume is obtained after data fusion from multiplanar slices. The influence of the contrast-to-noise ratio was tested on simulated images. The influence of slice thickness as well as the accuracy of the method were studied on phantoms. The absolute volume error was less than 2% for phantom volumes of 2-8 cm3, whereas the values obtained with conventional methods were much larger than the actual volumes. Clinical experiments were conducted, and the fuzzy logic method gave a volume lower than that obtained with the conventional method. Our fuzzy logic method allows volumes to be determined with better accuracy and reproducibility.