RESUMO
The right ventricular ejection fraction is rarely measured, as conventional diagnostic methods (radiology, echocardiography) are confronted with the problem of representing the right ventricle as a simple tridimensional geometrical model. This is not necessary with the radio-isotopic techniques. However, all those used for the measurement of right ventricular ejection fraction lead to important methodological problems. We have therefore developed a technique of measuring this parameter with an infusion of 81 m Kr. This radioactive gas is pure gamma-ray emitter with a 13 second period. Dissolved and infused intravenously, it is eliminated during the first passage through the lung. The continuous separation of the generator of 81 m Kr is performed with isotonic dextrose solution which is then infused for a period of 7 minutes. During this time, the activity detected by the scintillation camera inclined in the 30 degrees RAO projection is stored, together with the electrocardiogram in a computer. The precordial radioactivity of the retrocardiac lung tissue is subtracted after injection of 74 MBq of 99 mTc microspheres. A graph of right ventricular activity can then be reconstructed and the right ventricular ejection fraction calculated. The left ventricular ejection fraction is then measured with 99 mTc--labelled RBCs. This method allows the right ventricular ejection fraction to be measured in the RAO projection, the best incidence for the separation of the right atrial from the right ventricular activity without interference from left ventricular activity because of the pulmonary elimination of the Krypton radioactivity. The measurement performed on a large number of cardiac cycles allows a continuous study of the right ventricular ejection fraction. At the end of the infusion there is no circulating radioactivity so that the measurement can be repeated. This technique was used in 17 patients with acute myocardial infarction. In the 7 patients with anterior infarcts reduction of the left ventricular ejection fraction was the predominant finding (21,6 +/- 6,8%). The right ventricular ejection fraction was 34,2 +/- 6,4%. On the other hand, patients with a postero-inferior infarction had little change in left ventricular ejection fraction (59,2 +/- 12%) but those with right ventricular extension of their infarcts had very reduced right ventricular ejection fractions (less than 23%). The measurement of right ventricular ejection fraction with 81 m Kr is a reliable atraumatic method for diagnosing right ventricular infarction by the quantification of its functional impairment.
Assuntos
Débito Cardíaco , Criptônio , Infarto do Miocárdio/diagnóstico por imagem , Radioisótopos , Volume Sistólico , Adulto , Idoso , Eletrocardiografia , Feminino , Hemodinâmica , Humanos , Infusões Parenterais , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , CintilografiaRESUMO
Three patients presented with pulsatile tinnitus due to post-traumatic vascular lesions of the preauricular region. Lesions of this type should be investigated routinely by auscultation since the injury may have left no cutaneous traces.
Assuntos
Fístula Arteriovenosa/diagnóstico , Traumatismos Faciais/complicações , Artérias Temporais/lesões , Zumbido/etiologia , Adulto , Idoso , Aneurisma/patologia , Fístula Arteriovenosa/etiologia , Fístula Arteriovenosa/cirurgia , Auscultação , Artéria Carótida Externa/diagnóstico por imagem , Contusões/complicações , Diagnóstico Diferencial , Orelha Externa , Feminino , Humanos , Masculino , Radiografia , Artérias Temporais/diagnóstico por imagemRESUMO
The posterior manubrial ligament is part of the suspensory ligamentous system of the ossicles, and extends backwards from the posterosuperior spine of the tympanic notch to the postero-internal portion of the manubrium just below the neck of the malleus. It lies in relation to structures in the posterosuperior region of the tympanic barrier to downwards extension of epitympanic recess lesions during chronic otitis.
Assuntos
Orelha Média/anatomia & histologia , Ligamentos/anatomia & histologia , MasculinoRESUMO
Among the many procedures proposed for re-establishing bone continuity in cases with a mobile foot of the stapes, an effective solution has been found to be the employ of a malleus-foot of the stapes prosthesis. Austins prosthesis is surtable in such cases, but must be modified to adapt to different situations and to avoid complications. Surtably adapted in this way, good results can be obtained in the sequelae of chronic otitis and injuries.
Assuntos
Orelha Média/cirurgia , Implantes Cocleares , Humanos , Martelo/cirurgiaRESUMO
Dermatologic epithelioma of the nose is usually a basocellular and more rarely a spinocellular epithelioma. Small tumors less than 5 mm in diameter can be treated by electrocoagulation, whereas those over 1 cm should be treated by surgery or physical methods. Of a total of 144 cases of epithelioma operated upon, 10% were reconstructed by a flap. Increasing use is being made of local anesthesia with subsequent reduced hospital stay. The quality of the carcinologic results, similar to that of physical methods, and the excellent healing obtained, particularly in elderly patients, are arguments in favor of extensive surgery for epitheliomas in this region. The quality of the resection is difficult to evaluate, unless results of a fresh specimen examination are available. When not possible then it is preferable to await results of histology to show limits of excision before performing an autoplasty with flaps.
Assuntos
Carcinoma Basocelular/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Cutâneas/cirurgia , Retalhos Cirúrgicos , Humanos , Nariz , Cirurgia PlásticaRESUMO
A mild head injury could have played a role in the development of post-myringotomy cerebrospinal fluid rhinorrhea and otorrhea in an 18-month-old child with Mondini's syndrome. This notion of trauma may prevent exploration of the site of the fistula when these labyrinthic dysplasias are poorly understood. Once suspected, full radiological examination should precede closure of the gap using an otological approach.
Assuntos
Otorreia de Líquido Cefalorraquidiano/etiologia , Rinorreia de Líquido Cefalorraquidiano/etiologia , Traumatismos Craniocerebrais/complicações , Orelha Interna/anormalidades , Traumatismos Craniocerebrais/diagnóstico por imagem , Orelha Interna/diagnóstico por imagem , Humanos , Lactente , Radiografia , SíndromeRESUMO
Mesencephalic tractotomy employing the stereotaxic method was conducted 12 times in 11 patients with pain due to cervicofacial cancer only partially relieved by high doses of opiates. Immediate results were spectacular in 10 cases and partial on the other 2 occasions. However, relief was not permanent even in patients in whom the greatest improvement was obtained, and the usual analgesics had to be prescribed after 3 months. The operation, which requires only a short period of anesthesia, was always well supported, complications being anesthesia of one side of the body in 2 patients and convergence paralysis in two cases, one of which was transient. Mesencephalic tractotomy constitutes a new weapon for the treatment of diffuse cervicofacial cancer pain not responding to major medical treatment. Elective thermocoagulation of the Vth and IXth nerves was also successfully employed for systematized pains.
Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Mesencéfalo/cirurgia , Dor/cirurgia , Adulto , Denervação/efeitos adversos , Denervação/métodos , Eletrocoagulação , Seguimentos , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Técnicas EstereotáxicasRESUMO
Early and accurate detection of tumors, like the development of targeted treatments, is a major field of research in oncology. The generation of specific vectors, capable of transporting a drug or a contrast agent to the primary tumor site as well as to the remote (micro-) metastasis would be an asset for early diagnosis and cancer therapy. Our goal was to develop new treatments based on the use of tumor-targeted delivery of large biomolecules (DNA, siRNA, peptides, or nanoparticles), able to induce apoptosis while dodging the specific mechanisms developed by tumor cells to resist this programmed cell death. Nonetheless, the insufficient effectiveness of the vectorization systems is still a crucial issue. In this context, we generated new targeting vectors for drug and biomolecules delivery and developed several optical imaging systems for the follow-up and evaluation of these vectorization systems in live mice. Based on our recent work, we present a brief overview of how noninvasive optical imaging in small animals can accelerate the development of targeted therapeutics in oncology.
Assuntos
Diagnóstico por Imagem/métodos , Descoberta de Drogas/métodos , Neoplasias/diagnóstico , Dispositivos Ópticos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Linhagem Celular , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Camundongos , Camundongos Nus , Microscopia de Fluorescência/métodos , Neoplasias/tratamento farmacológico , Radioterapia (Especialidade)/métodosRESUMO
We describe a novel method for localizing a fluorescent inclusion in a homogeneous turbid medium through the use of time-resolved techniques. Based on the calculation of the mean time of the fluorescence curves, the method does not require a priori knowledge of either the fluorescence lifetime or the mean time of the instrument response function since it adopts a differential processing approach. Theoretical expressions were validated and experiments for assessing the accuracy of localization were carried out on liquid optical phantoms with a small fluorescent inclusion. The illumination and detection optical fibers were immersed in the medium to achieve infinite medium geometry as required by the model used. The experimental setup consisted of a time-correlated single-photon counting system. Submillimeter accuracy was achieved for the localization of the inclusion.
Assuntos
Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/instrumentação , Nanopartículas/ultraestrutura , Nefelometria e Turbidimetria/instrumentação , Microscopia de Fluorescência/métodos , Nefelometria e Turbidimetria/métodos , Tamanho da Partícula , Imagens de FantasmasRESUMO
This paper presents a new fluorescence diffuse optical tomographic (fDOT) system and its associated reconstruction method. It is able to reconstruct the fluorescence yield even in heterogeneous and highly attenuating regions. Furthermore our reconstruction method makes mouse inspection without immersion in optical index matching liquid (Intralipid and ink) possible. Some phantom experiments have been carried out to characterize this new fDOT system and to validate its use for heterogeneous media. A mice study consisting in the follow up of the lungs at different stages of tumor development is then related. These results validate the use of our system for biological studies of small animals.
Assuntos
Fluorescência , Tomografia Óptica/métodos , Animais , Feminino , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Nus , Óptica e Fotônica , Tomografia Óptica/instrumentaçãoRESUMO
Fluorescence-enhanced diffuse optical tomography is expected to be useful to the collection of functional information from small animal models. This technique is currently limited by the extent of tissue heterogeneity and management of the shape of the animals. We propose an approach based on the reconstruction of object heterogeneity, which provides an original solution to the two problems. Three evaluation campaigns are described: the first two were performed on phantoms designed to test the reconstructions in highly heterogeneous media and noncontact geometries; the third was conducted on mice with lung tumors to test fluorescence yield reconstruction feasibility in vivo.