RESUMO
BACKGROUND: Noncommunicable diseases (NCDs) lead to drastic metabolic alterations with associated energy balance and body weight changes, two related physiological processes regulated by the brain. Polyphenol-based treatments for NCDs have emerged as a promising therapy, which seems to involve the energy balance modulation. However, it remains unclear what the most effective polyphenols-based treatment is to attenuate adverse effects in the energy balance of NCDs. OBJECTIVES: This systematic review aimed to evaluate the literature on the metabolic and neurological effects of polyphenols-based treatment in rodent models of NCDs. METHODS: Literature search was carried out in the following databases: CINAHL, Medline/PubMed, SCOPUS, and Web of Science. For title and abstract screening, original papers with polyphenols exposure in rodents were selected. For full-text screening, studies with models of NCDs that reported metabolic and neurological outcomes when treated with polyphenols were selected for inclusion in this review. RESULTS: 23 articles, using individual compound (11 articles) or polyphenols extracts (12 articles), were included in this review: 5 articles using tea polyphenols, 12 articles using grape-derived polyphenols, 3 articles using the polyphenol quercetin, and 3 articles using other polyphenol sources. Most results agree on the beneficial effect of polyphenols in attenuating alterations in energy balance and body weight. Such effects were associated with neuroprotective responses in different brain areas including hippocampus and hypothalamus. CONCLUSION: In conclusion, this review shows that the treatment with polyphenols, especially resveratrol or quercetin, attenuates the adverse effects of NCDs on energy balance and are associated with neuroprotective effects.
Assuntos
Doenças não Transmissíveis , Polifenóis , Animais , Peso Corporal , Polifenóis/farmacologia , Quercetina , RoedoresRESUMO
PURPOSE: State-of-the-art imaging of the normal and pathologic vestibule. METHODS AND MATERIAL: This study is based on the experience of three French imaging centers (Val de Grâce, Bégin, and Saint-Antoine hospitals) working with 1- and 1.5-tesla magnetic resonance units and high-resolution computed tomography, and it includes a review of the literature. Computed tomography is performed with a high-resolution program, matrix 512 x 512, field of view 9.6 cm, joined 1-mm section, overlapped sections every 0.5 mm, axial and coronal sections, or reformatted images. High-resolution magnetic resonance imaging (matrix 512 x 384), field of view 18 cm, is used with fast T2-weighted sequences (sections 3 or 2 mm thick, constructive interference in steady state, T2-weighted gradient echo sequence three-dimensional Fourier transformation). A joined section of 0.7 mm in any direction is obtained if necessary. Superimposition of computed tomography and magnetic resonance imaging with a stereotactic technique by identification of identical anatomic points is sometimes used. RESULTS: We review the interest and place of computed tomography and magnetic resonance imaging in the diseases of the labyrinth and internal auditory canal related to abnormal vestibular functions: inflammatory labyrinthitis, vestibular hemorrhages, sclerosing and ossifying labyrinthitis, traumatism, malformations, perilymphatic fistulas, otosclerosis, tumors, cochleovestibular neuritis, and hydrops of the endolymphatic system.
Assuntos
Doenças Vestibulares/diagnóstico , Vestíbulo do Labirinto/diagnóstico por imagem , Vestíbulo do Labirinto/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Doenças Vestibulares/diagnóstico por imagemRESUMO
Several kinds of images, each giving a different information, are now available to radiologists. The MRI images have excellent contrast resolution and enable soft tissues to be differentiated, but they do not distinguish structures with low water content, notably air and bone, whereas these are easily recognized by CT. The aim of this study is to present a simple, entirely radiologist-supervised method to examine the radiological data of any patient, obtained from several kinds of images. MRI is performed using a GEMS Signa, 1.5 Tesla, 4.9 version magnet. Acquisitions are T1- or T2-weighted spin-echo or gradient sequences, with a 256 or 512 matrix, on axial sections, with of without contrast injection. CT is performed using a GEMS Hi Speed scanner. Acquisitions are obtained on a 512 matrix and with a "Soft" or "Bone" filter, without contrast injection. The two series of sections are transmitted, through an Etherne network, to a Sun console where the two corresponding volumes are reconstructed on a GEMS Voxtol by means of a 3-dimensional soft ware for image treatment. At least 3 couples define the rotation and translation required for one of the two volumes to reset it in the guide mark of the other. The soft ware then looks for the best transformation, in terms of least square, between the two 3-dimensional volumes. The calculation demands only a few seconds. One of the two objects is then recalculated in the guide mark of the other. The cursor positioned by the user on any point of the object is linked to a second cursor which will automatically position itself on the corresponding point of the other object. The accuracy obtained (about one millimeter) is specified by the soft ware which indicates how to improve resetting. In addition to its teaching value, this superimposition image can help in the diagnosis and can be used for surgical stimulation because it is possible to mix the images. This mixing gives access to a new type of imaging, since the images spared can be reconstructed in volume, and treated in all planes, as a CT or MRI examination. The term "Anatomical Reconstruction Images" may be suggested for this new type of examination. Beside intermodal comparison, one may also imagine that the soft ware can be used to follow up the patient over time (repeat MRI) or to make comparisons between several objects, although the elastic resetting method is more often appropriate in the second case.
Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Meios de Contraste , Filtração/instrumentação , Seguimentos , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador/métodos , Análise dos Mínimos Quadrados , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Planejamento de Assistência ao Paciente , Intensificação de Imagem Radiográfica , Radiologia/educação , Sistemas de Informação em Radiologia , Rotação , Software , Procedimentos Cirúrgicos Operatórios , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/métodosRESUMO
The authors have reviewed 12 cases of severe cranial trauma examined by MRI and determine the position of this method in exploration in the acute phase. Since the 1970's, computerized tomography (CT) has completely modified the emergency diagnosis. Intra- and extracerebral blood effusions are readily recognized, but the patient is often in a dangerous situation and little help is obtained from CT which does not detect shearing lesions located in the white matter, the corpus callosum or the brain stem. Early MRI examination performed with gradient-echo sequences provides a better anatomico-clinical correlation, a better prognostic approach and even a new therapeutic approach.
Assuntos
Lesões Encefálicas/diagnóstico , Imageamento por Ressonância Magnética , Reação de Fase Aguda/diagnóstico , Reação de Fase Aguda/diagnóstico por imagem , Adulto , Concussão Encefálica/diagnóstico , Concussão Encefálica/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Retrospectivos , Fraturas Cranianas/diagnóstico , Fraturas Cranianas/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
The authors report their experience of cerebral stereotaxis for biopsy purposes. Since January 1990, they have been using MRI which provides vascular images and makes it possible to simulate surgical procedures beforehand. The authors have developed a specific program on an independent console. MRI sections are acquired with a 1.5 Tesla Sigma (G.E.) apparatus in 3DFT volume and T1-weighted SPRG sequence, after gadolinium injection. The sections are memorized and reconstructed by a SUN computer. After automatic recognition of the referential of a Leksell G plane, the target and the puncture vector are chosen by a radiologist and a neurosurgeon. The X, Y, Z co-ordinates of the point of puncture and the angles of penetration into the cerebral volume are delivered automatically. Provided the entire measurement chain is constantly tested and corrected if necessary, the precision of the system is of the order of one millimetre.
Assuntos
Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética , Técnicas Estereotáxicas , Mapeamento Encefálico/instrumentação , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Técnicas Estereotáxicas/instrumentaçãoRESUMO
Progressive Multifocal Leukoencephalopathy is a demyelinating disease. MRI shows high signal intensity areas on T2w sequence and low intensity aeras on T1w sequence, without enhancement after intravenous contrast injection. The involvement of arcuate fiber (U fibers) creates a sharp border with the cortex. There is no mass effect. Involvement of parieto-occipital areas is frequent. The lesions may be uni or bilateral, single or multiple; bilateral lesions are asymmetric. This typical appearance on MR images occurs in 90% of the patients with PML. Some atypical patterns may occur: focal hemorrhage, atrophy, faint peripheral enhancement and involvement of deep gray matter (basal ganglia). In most cases, the clinical and MR features provide the diagnosis. The main differential diagnosis, in MRI, is HIV-leukoencephalitis, but lesions are diffuse, less intense on T2w sequence and not visible on T1, without involvement of the arcuate fibers. Stereotactic biopsy should be performed only for atypical lesions, particularly in case of predominant involvement of deep gray structures.
Assuntos
Leucoencefalopatia Multifocal Progressiva/diagnóstico , Imageamento por Ressonância Magnética , Complexo AIDS Demência/diagnóstico , Núcleo Arqueado do Hipotálamo/patologia , Atrofia , Biópsia , Córtex Cerebral/patologia , Hemorragia Cerebral/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Humanos , Técnicas EstereotáxicasRESUMO
To assess the value of MRI for meningioma of the posterior cerebral fossa, in correlation with surgical and pathological findings, we retrospectively reviewed 31 cases. The patients (24 females and 6 males ranging in age from 25 to 79 years) were preoperatively studies on a 1,5 T MR imager (GEMS Signa) between july 1989 and november 1993. The protocol included: 1. MR scan with axial sections in T2-weighted spin-echo sequence (3 mm thickness), T1-weighted spin-echo sequence before and after gadolinium injection (3-5 mm thickness), coronal and sagittal T1-weighted sections performed after injection. 2. Surgery reports. 3. Histopathological reports; the predominant histological subtype of each tumor was graded according to the classification scheme of Russel and Rubinstein. We focused on five items: 1. The site of the dural attachment of the meningioma. 2. Tumoral extensions (to the tentorium, to the jugular foramen, to the internal auditory canal). 3. The meningioma signal in T1- and T2-weighted sequence using the same visual scoring system for grading signal intensities as Elster and al. 4. Secondary features (necrosis, cysts, calcifications) within the tumor. 5. Interface between meningioma and encephalic structures. Meningiomas arose from the posterior surface of the petrous bone in 74% of the cases and from the clivus in 9.6%. Meningiomas were bulky at the time of diagnosis as since tumoral arrow overtook 2 cm in 64.5% of the cases. Surgical approach was guided by an anatomo-radiologic classification based on the exact site of tumoral dural attachment. This determination relied on: 1. Osseous reaction noted in 58% of the cases (enostosic spur in 19%, localized osseous thickening in 16%). 2. The trigeminal nerve displacement by the tumor; in case of clival meningioma extended to the petrous apex, this nerve is displaced outside; otherwise, meningioma of the petrous bone extended to the clivus displaced the trigeminal nerve inside. 3. Radiate structure within tumor converging to vascular basal pole of the meningioma noted in 42% of the cases. Tentorial involvement remained a difficult diagnosis on MR images. It was affirmed when the tumor extended on the opposing surface of the tentorium and when focal hypersignal existed through the usual tentorial hyposignal on T2-weighted images and T1-weighted images after gadolinium. On the other hand, tentorial linear dural enhancement adjacent to the tumor was not a reliable sign (error in 15.8% of the predicted cases). The meningothelial (syncitial) type was noted in 67.7% of the cases. (ABSTRACT TRUNCATED AT 450 WORDS)
Assuntos
Imageamento por Ressonância Magnética , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Adulto , Idoso , Calcinose/diagnóstico , Calcinose/patologia , Meios de Contraste , Fossa Craniana Posterior/patologia , Fossa Craniana Posterior/cirurgia , Cistos/diagnóstico , Cistos/patologia , Técnicas de Diagnóstico por Cirurgia , Dura-Máter/patologia , Feminino , Gadolínio , Humanos , Aumento da Imagem , Masculino , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Necrose , Invasividade Neoplásica , Osso Petroso/patologia , Estudos Retrospectivos , Nervo Trigêmeo/patologiaRESUMO
OBJECTIVE: In 1988, the neurosurgeons and neuroradiologists at the Val-de-Grâce hospital decided to create a stereotaxis site using advanced medical imaging date (CT-scan or MRI). METHODS: Two MRI machines and on CT unit were linked to a network (ETHERNET) available for radiologists in 1989. Neurosurgeons adapted stereotaxis sites using Leksell, Fisher and CRW software for MRI. A data processing program recognizing these sites was developed for stereotaxic biopsies based on MRI data. The network was extended in 1992 to the radiotherapy unit for multiple beam stereotaxic irradiations. Finally from 1994, when a computer-guided microscope (Zeiss MKM) was installed, nearly all neurosurgical procedures were conducted under stereotaxic conditions. RESULTS: Since 1989, approximately 900 computer-guided stereotaxic biopsies have been performed with precision in the millimeter range. Since 1994, the Zeiss MKM microscope has been used for 120 computer-guided procedures with the frameless stereotaxic technique guided from landmarks on the outer cranium or attached to the scalp. Mean precision obtained with landmarks was 1.2 mm and 2.8 mm with scalp markers. CONCLUSION: These techniques of computer-assisted neurosurgery based on advanced medical imaging techniques has been revolutionary for surgical approach to intracranial and intracerebral diseases. Smaller assess routes and precise pathways allow an approach to formerly inoperable lesions with minimal risk.
Assuntos
Encéfalo/cirurgia , Redes de Comunicação de Computadores , Simulação por Computador , Terapia Assistida por Computador , Biópsia , Encefalopatias/radioterapia , Encefalopatias/cirurgia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Processamento Eletrônico de Dados , Glioma/radioterapia , Glioma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Meningioma/radioterapia , Meningioma/cirurgia , Microscopia , Neurocirurgia , Sistemas de Informação em Radiologia , Radiologia Intervencionista , Radioterapia Assistida por Computador , Software , Técnicas Estereotáxicas , Tomografia Computadorizada por Raios XRESUMO
Based on a series of about a hundred CT-guided stereotactic biopsies, the basic principles of stereotaxic approach of the brain are reviewed. The authors also report their preliminary experience of stereotaxic aspiration in the management of brain abscesses and hypertensive intracerebral hematomas. CT-guided stereotaxic aspiration is useful in the management of brain abscesses and is a viable treatment modality of hypertensive hematomas.
Assuntos
Biópsia por Agulha , Abscesso Encefálico/terapia , Hemorragia Cerebral/terapia , Hematoma/terapia , Técnicas Estereotáxicas , Adulto , Idoso , Emergências , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Arteriography failed to detect a pancreatic pseudocyst complicated by hemorrhage, a positive diagnosis being established only after CT scanning. Identification of this rare lesion by angioscan imaging illustrates. The value of this technique, which provides data on vascular dynamics, rapidly, in the selected plane of the section. Results in this case demonstrate the very close correlation between Ct scan images and pathological findings.
Assuntos
Hemorragia/diagnóstico por imagem , Cisto Pancreático/diagnóstico por imagem , Pseudocisto Pancreático/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Hemorragia/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Pseudocisto Pancreático/diagnósticoRESUMO
The MRI technology may be the starting-point of geometric distorsion. The mathematical preciseness of a spatial location may be disturbed and alter the guidance of an MRI interventionnal act, especially in stereotactic brain biopsy. A review of the literature shows errors of 1 to 1.5 mm. Our results show an error of 0.16 +/- 0.66 mm. The control of quality: homogeneity and calibration of magnetic-field gradients, permit an improve of the balistic preciseness and give permission to realize the guidance of a stereotactic brain biopsy with the alone MRI.
Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Técnicas Estereotáxicas , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodosRESUMO
Recent works show the possibility of MRI to study brain functionalities. Today, treatment relies essentially on addition and subtraction of images accumulated during rest and activity periods. But this technic is not discriminating and we have developed a software to see and treat images with filtering algorithm and statistical analysis of signal. The first results are given. Perfections are possible and are being realized.
Assuntos
Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Encéfalo/fisiologia , HumanosRESUMO
After 150 stereotactic biopsy with CT, the team of Val-de-Grâce has made these ones with MRI and simulation of the complete procedure with an independent computer. The result of 85 biopsies is reported. This one imply the acquisition of 3DFT millimetrics slices, the transfer by Ethernet network on a computer where a specific software treat the data and allow to establish the better course for the needle biopsy. The constraints of quality are very important and some test must be executed. The diagnosis are established, avoiding an unless trepanation.
Assuntos
Neoplasias Encefálicas/patologia , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Tumores Neuroectodérmicos Primitivos Periféricos/patologia , Técnicas Estereotáxicas , Adulto , Biópsia , Neoplasias Encefálicas/diagnóstico , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroectodérmicos Primitivos Periféricos/diagnósticoRESUMO
Fifty percent of intracranial epidermoid cysts are located in the cerebral posterior fossa. Clinical presenting features are not specific and vary according to cyst topography and mass effect on neighbouring structures. In CT, the lesion is hypodense as related to the cerebral tissue, but with no specificity. In MRI, the typical form shows quasi-pathognomonic morphologic characters with polyedric contours, a marble aspect, a reduced mass effect as compared to the tumor volume and an evolution signal close to that of cerebrospinal fluid, with no increase after contrast agent injection. Some primary cholesteatomas have a different radiological aspect. They can be hyperdense in CT and have a spontaneous hyperintense signal in T1-weighted MRI sequence. They correspond to complicated epidermoid cysts associated with hemorrhages and granulomatous meningeal reaction whose constitution is very very close to that of cholesterine granulomas.
Assuntos
Encefalopatias/diagnóstico por imagem , Colesteatoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Encefalopatias/diagnóstico , Colesteatoma/diagnóstico , Fossa Craniana Posterior , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
A CT scan allowed simple diagnosis of the affection in three patients with the blue tympanic membrane syndrome. Lesions included prolapse of the internal jugular vein sinus into the tympanic cavity, an aberrant trajectory of the internal carotid artery in the middle ear and a tympano-jugular glomus tumor. Angiographic investigation of the latter lesion was performed more as a pre-treatment procedure rather than for diagnostic purposes, since it served as a guide to surgery, consisting usually of embolization.
Assuntos
Artéria Carótida Interna/anormalidades , Neoplasias da Orelha/diagnóstico por imagem , Tumor do Glomo Jugular/diagnóstico por imagem , Veias Jugulares/diagnóstico por imagem , Paraganglioma Extrassuprarrenal/diagnóstico por imagem , Membrana Timpânica , Adulto , Cor , Orelha Média/irrigação sanguínea , Feminino , Humanos , Masculino , Prolapso , Tomografia Computadorizada por Raios X , Membrana Timpânica/diagnóstico por imagemRESUMO
AIM: Determining which semiological criteria might help to suggest lymphoma when an intracerebral mass in observed in a patient with AIDS. The use of these criteria might shorten the duration of the anti-toxoplasmic test treatment and to perform puncture earlier. The fast growth of the lymphomas may account for the rapid death of these patients if untreated, but as a corollary, its increase in size can be objectively measured over a short period, about ten days. MEANS: Retrospective study of 17 lymphomas diagnosed with stereotaxic puncture. RESULTS: The most discriminating criteria are ventricular encasement or an original site in the white matter, as well as the moderate character of the edema and of the mass effect relative to the volume of the tumor. Other arguments also help: simple lesion, large size, sinuous contour, no signs of hemorrhage. CONCLUSION: The diagnosis of lymphoma can often be proposed at once. A control must then be performed very soon, with stereotaxic puncture if the volume of the lesion has increased in the meantime.
Assuntos
Neoplasias Encefálicas/diagnóstico , Linfoma Relacionado a AIDS/diagnóstico , Imageamento por Ressonância Magnética , Técnicas Estereotáxicas , Adulto , Biópsia por Agulha , Neoplasias Encefálicas/patologia , Feminino , Humanos , Linfoma Relacionado a AIDS/patologia , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
110 cases of neurinomas of the VIIIth with APC extension (104 patients) were studied using MRI or CT. Classically, it is said that the tumoral mass is centered on the IAC. In our study, among 110 cases of neurinomas, only 9 were centered along the axis of IAC on axial slices and only 23 on coronal slices. The anterior development of the tumor is never more than 1 cm, except in 3 cases of large and multicystic neurinoma. We suggest that the anterior development of large tumors is limited by the VIIth nerve.
Assuntos
Neuroma Acústico/patologia , Osso Temporal , Adolescente , Adulto , Idoso , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Invasividade Neoplásica , Neuroma Acústico/diagnóstico , Neuroma Acústico/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
OBJECT: To compare prospectively high resolution fast spin echo T2 weighted (FSE-T2W) images and gadolinium-enhanced spin echo T1 weighted images for diagnosis of pathology of the internal auditory meatus (IAM). PATIENTS AND METHODS: 114 patients underwent MR imaging at 1.5 T with the following protocol: axial images; whole brain FSE-T2W sequence (256 matrix); 2 sequences focused on IAM with high resolution FSE-T2W acquisitions (512 matrix, 3 mm sections with 1.5 mm overlapping); pre and postcontrast T1 weighted sequences focused on IAM. Examinations were viewed by senior neuroradiologists. RESULTS: 31 lesions were detected in the IAM by high resolution FSE-T2W images; 25 lesions were found in the IAM by postcontrast T1 weighted images, i.e. 6 false-positive results and none false-negative. On the basis of 228 studied IAMs the sensitivity, specificity and negative predictive value of this high resolution FSE-T2W sequence were 100%, 97% and 100% respectively. CONCLUSION: Gadolinium enhanced sequence is not indispensable if high resolution FSE-T2W images are normal. Gadolinium-enhanced sequence remains essential in others equivocal cases (difficult diagnosis or abnormal IAM).
Assuntos
Orelha Interna/patologia , Gadolínio , Doenças do Labirinto/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Transtornos da Audição/diagnóstico , Transtornos da Audição/etiologia , Humanos , Doenças do Labirinto/complicações , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/diagnóstico , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Vertigem/diagnóstico , Vertigem/etiologiaRESUMO
Involvement of the deep grey matter is unusual in Progressive Multifocal Leukoencephalopathy (PML), which is disease of the white matter. Basal ganglia involvement is usually secondary to extension from lesions of adjacent white matter and easy to recognize. We report a biopsy-proven case of PML in which lesions were mainly thalamic.
Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Leucoencefalopatia Multifocal Progressiva/etiologia , Doenças Talâmicas/etiologia , Adulto , Humanos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/patologia , Imageamento por Ressonância Magnética , Masculino , Doenças Talâmicas/diagnóstico , Doenças Talâmicas/patologia , Fatores de TempoRESUMO
Three cases of renal ischemia diagnosed by Computed Tomography (CT) are presented. The pathophysiology of renal ischemia which accounts for the CT findings observer in these cases are reviewed. In the appropriate climate setting a diagnosis of renal ischemia may be made by CT, when a zone or zones of low attenuation after injection and enhancement of these same zones 6 to 72 hours later are observed in the kidney.