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71.
David C. Farlow M.B. B.S. F.R.A.C.P. Peter R. Chapman M.B. B.S. F.R.A.C.P. Simon M. Gruenewald M.B. Ch.B. M.R.C.P. M.Sc. F.R.A.C.P. Vincent F. Antico M.B. B.S. F.R.A.C.P. Geoffrey C. Farrell M.D. F.R.A.C.P. J. Miles Little M.D. M.S. F.R.A.C.S. F.A.C.S. 《World journal of surgery》1990,14(4):463-467
Noninvasive diagnosis of cavernous hemangioma of the liver is an important step in the investigation of patients with focal hepatic lesions since biopsy may result in life-threatening hemorrhage. To determine the diagnostic accuracy of 99m-technetium red blood cell (99mTc-RBC) imaging with tomography, 50 patients with various types of focal liver lesions were studied. Thirty-two patients had 45 hemangiomas and 7 other benign lesions while 18 patients had either primary (n=8) or secondary (n=10) hepatic malignancies. Tomographic imaging identified 12 more hemangiomas than planar imaging, improving sensitivity from 53% to 80%, and was found most useful for detection of smaller lesions (mean size, 2.1 cm). Specificity for hemangiomas was 100% with all lesions greater than 1.9 cm showing the characteristic scintigraphic pattern of blood-pooling on delayed images. There was excellent agreement between 2 independent observers concerning interpretation of tomographic images (89% for the hemangioma group and 100% for other patients). Therefore99mTc-RBC scintigraphy with tomography is an accurate diagnostic technique in the investigation of cavernous hemangiomas. Its major value resides in its ability to distinguish hemangiomas from other types of hepatic pathology.
Resumen El diagnóstico no invasivo del hemangioma cavernoso del hígado es un paso de importancia en el proceso de investigación de pacientes con lesiones hepáticas focales, puesto que la biopsia puede resultar en hemorragia de consecuencias potencialmente fatales. Con el objeto de determinar la certeza diagnóstica de la tomografía con glóbulos rojos marcados con tecnecio 99m, se estudiaron 50 pacientes con varios tipos de lesiones hepáticas focales. Treinta y dos pacientes presentaron 45 hemangiomas y 7 lesiones benignas, en tanto que 18 pacientes presentaron neoplasias malignas primarias (n=8) o secundarias (n=10). Las imágenes tomográficas obtenidas por este método lograron identificar 12 hemangiomas más, en comparación con imágenes convencionales, aumentando la sensibilidad de 53% a 80%, y demostró ser de máxima utilidad para la detección de las lesiones más peque¯nas (tamaño promedio, 2.1 cm). La especificidad para los hemangiomas fue 100%, con todas las lesiones mayores de 1.9 cm exhibiendo el patrón centelleográfico característico de estancamiento sanguíneo en las imágenes tardías. Se encontró excelente correlación entre 2 observadores independientes en la interpretación de las imágenes tomográficas (89% para el grupo de pacientes con hemangiomas y 100% para el resto de los pacientes). En consecuencia, la escintigrafía con glóbulos rojos marcados con99mTc aparece como una técnica certera en el diagnóstico de los hemangiomas cavernosos. Su mayor valor reside en su habilidad para diferenciar los hemangiomas de otra clase de patología.
Résumé Le diagnostic non invasif d'hémangiome caverneux du foie est une étape importante dans l'investigation des patients ayant des lésions hépatiques focales, puisque la biopsie risque de se résoudre par une hémorrhagie menaçant le pronostic vital. Pour définir la précision diagnostique de la tomoscintigraphie après marquage des hématies au technetium 99m (99mTc), on a étudié 50 patients ayant des types différents de lésions focales du foie. Trente-deux patients avaient 45 hémangiomes et 7 lésions bénignes tandis que 18 patients avaient des tumeurs hépatiques malignes soit primaires (n=8) soit secondaires (n=10). L'imagerie tomographique a identifié 12 hémangiomes de plus que l'imagerie planaire, améliorant la sensibilité de 53% à 80% et s'est avérée très utile pour détecter les lésions plus petites (taille moyenne, 2.1 cm). La spécificité pour les hémangiomes était de 100% pour toutes les lésions dépassant 1.9 cm montrant les caractères scintigraphiques typiques d'accumulation de sang sur les images retardées. Il y a eu concordance totale entre 2 observateurs indépendents sur l'interprétation des images tomographiques (89% pour le groupe des hémangiomes et 100% pour les autres patients). Voilà pourquoi la scintigraphie99mTc avec tomographie est une technique de diagnostic précis dans l'investigation des hémangiomes caverneux. Sa valeur essentielle est sa capacité de distinguer les hémangiomes des autres types de pathologie hépatique.相似文献
72.
Patrick Courtheoux M.D. Dominique Maiza Jean Mani Vincent Mercier Jacques Theron 《Cardiovascular and interventional radiology》1988,11(6):340-342
A case of postnephrectomy arteriovenous fistula of the right renal pedicle is reported here. The diagnosis was confirmed by
angiography, and successful treatment was achieved using detachable balloon. 相似文献
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Elevations of epidermal growth factor (EGF) and Ca2+ concentrations in the wound site are associated with reepithelialization during wound healing. In addition, Ca2+ and EGF can both induce increases in matrix metalloproteinase‐9 (MMP‐9) synthesis. However, little is known about the interplay of these events in regulating the migration properties of primary keratinocytes on collagen I, the most abundant extracellular matrix component in the skin. We found that EGF stimulated both chemokinetic and chemotactic migration of primary keratinocytes on collagen I; however, MMP‐9 was required for EGF‐stimulated chemotaxis but not EGF‐stimulated chemokinesis. Calcium at 0.5 mM stimulated chemokinetic migration of keratinocytes. Together, Ca2+ and EGF stimulated higher levels of chemokinesis than either stimulus alone. Furthermore, Ca2+ could restore the ability of keratinocytes from MMP‐9 null mice to undergo EGF‐stimulated chemotaxis. The phosphatidylinositol‐3 kinase inhibitor LY294002 inhibited both EGF‐ and Ca2+‐stimulated chemokinetic migration. In contrast, the MEK inhibitor PD98059 blocked Ca2+‐ but not EGF‐stimulated chemokinetic migration of keratinocytes. A combination of PD98059 and LY294002 was required to inhibit Ca2+ enhancement of EGF‐stimulated migration completely. Calcium‐stimulated chemokinesis was completely blocked by either the protein kinase C‐α inhibitor Gö6976 or the src/fyn inhibitor PP2. Using primary keratinocytes, our results showed how the combined action of Ca2+, EGF, and MMP‐9 regulated the contributions of extracellular‐regulated kinase and phosphatidylinositol‐3 kinase toward chemokinetic and chemotactic migration of keratinocytes. 相似文献
77.
Albertine Dubois Julien Dauguet Anne-Sophie Herard Laurent Besret Edouard Duchesnay Vincent Frouin Philippe Hantraye Gilles Bonvento Thierry Delzescaux 《Journal of cerebral blood flow and metabolism》2007,27(10):1742-1755
Besides the newly developed positron emission tomography scanners (microPET) dedicated to the in vivo functional study of small animals, autoradiography remains the reference technique widely used for functional brain imaging and the gold standard for the validation of in vivo results. The analysis of autoradiographic data is classically achieved in two dimensions (2D) using a section-by-section approach, is often limited to few sections and the delineation of the regions of interest to be analysed is directly performed on autoradiographic sections. In addition, such approach of analysis does not accommodate the possible anatomical shifts linked to dissymmetry associated with the sectioning process. This classic analysis is time-consuming, operator-dependent and can therefore lead to non-objective and non-reproducible results. In this paper, we have developed an automated and generic toolbox for processing of autoradiographic and corresponding histological rat brain sections based on a three-step approach, which involves: (1) an optimized digitization dealing with hundreds of autoradiographic and histological sections; (2) a robust reconstruction of the volumes based on a reliable registration method; and (3) an original 3D-geometry-based approach to analysis of anatomical and functional post-mortem data. The integration of the toolbox under a unified environment (in-house software BrainVISA, http://brainvisa.info) with a graphic interface enabled a robust and operator-independent exploitation of the overall anatomical and functional information. We illustrated the substantial qualitative and quantitative benefits obtained by applying our methodology to an activation study (rats, n=5, under unilateral visual stimulation). 相似文献
78.
79.
Parish P Sedghizadeh Derek Wong Charles F Shuler Vincent Linz John R Kalmar Carl M Allen 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e30-e34
The calcifying epithelial odontogenic tumor (CEOT), or Pindborg tumor, is a rare and benign odontogenic neoplasm that affects the jaw. The most common manifestation of CEOT is a unifocal or localized lesion of the involved jaw, which may appear clinically as a hard tissue swelling and radiographically as a mixed radiolucent-radiopaque mass. In this article, we present a unique case of CEOT affecting multiple sites in the maxilla and mandible of a 51-year-old white man. Though biopsy samples from all involved sites revealed similar histopathologic features consistent with CEOT, the fact that there was a multifocal presentation is an unusual phenomenon for CEOT and has never been reported. Multifocal odontogenic lesions are not typical but have been observed in conditions associated with known genetic mutations. For example, multiple odontogenic keratocysts are the most common feature of the inherited condition known as nevoid basal cell carcinoma syndrome. This case, however, is the first one to demonstrate that there may be a multifocal variant of CEOT that has not been previously recognized. 相似文献
80.
William T Mahle Robert N Vincent Alexandria M Berg Kirk R Kanter 《The Journal of heart and lung transplantation》2005,24(1):63-66
BACKGROUND: Hydroxymethylglutaryl CoA reductase inhibitors (statins) have been demonstrated to reduce the risk of developing coronary allograft vasculopathy (CAV) following heart transplantation in adults and are used routinely in many centers. CAV and lipid abnormalities have been reported to be less prevalent in pediatric heart transplant recipients. It is not known whether statins reduce the risk of CAV in this population METHODS: A retrospective review was performed to analyze the risk factors for developing CAV following pediatric heart transplantation with particular attention to the impact of pravastatin therapy. The study population was comprised of 129 pediatric patients who underwent 142 heart transplants at our institution from 1988 to 2003. The outcome variable was freedom from CAV, CAV being determined by coronary angiography or autopsy. RESULTS: CAV was identified in 25 recipients at a median of 3.7 years after transplantation. There were 331 patient-years of pravastatin therapy. Pravastatin therapy resulted in a reduction in total cholesterol levels, 162 +/- 29 to 137 +/- 20 mg/dl, p = 0.01. In multivariate analysis the use of pravastatin was associated with a lower incidence of CAV (p = 0.03), whereas an increased frequency of late rejection (p = 0.003) and earlier year of transplantation (p = 0.04) were associated with increased risk of CAV. CONCLUSIONS: The routine use of pravastatin was associated with a lower risk following pediatric heart transplantation. Further studies into the relationship between lipid abnormalities, inflammation and rejection, and the development of CAV in children are warranted. 相似文献