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1.
Dentomaxillofac Radiol ; 43(1): 20130289, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24170803

RESUMO

The purpose of this study was to assess the feasibility of dental ultrasound with conventional sonographic equipment. The teeth of three adult volunteers who had cone beam CT examinations performed previously with clinical indications and one extracted tooth were examined using linear and compact (hockey stick) sonographic probes. The sonographic images were compared with cone beam CT images reconstructed accordingly. Dental pulp spaces were demonstrated in all teeth not covered with prosthetic crowns. The dentin and pulp were best visualized at the level of the neck of the teeth. The dentin was hypoechoic, and the superficial layer comprising the cementum and the pulp spaces were hyperechoic. Dental ultrasound is feasible with general purpose sonographic machines. The buccal surfaces of all teeth are accessible with a compact (hockey stick) probe. Visualization and differentiation of dental pulp spaces, dentin and the superficial layer comprising cementum is possible in the portions of teeth not covered by the alveolar bone or prosthetic crowns. The dental pulp spaces are best seen at the level of the tooth neck. Pulp and endodontic fillings can be distinguished on ultrasound.


Assuntos
Polpa Dentária/diagnóstico por imagem , Adulto , Tomografia Computadorizada de Feixe Cônico/métodos , Cemento Dentário/diagnóstico por imagem , Cavidade Pulpar/diagnóstico por imagem , Dentina/diagnóstico por imagem , Estudos de Viabilidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Colo do Dente/diagnóstico por imagem , Coroa do Dente/diagnóstico por imagem , Transdutores , Ultrassonografia
2.
J Ultrasound ; 10(3): 128-34, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23396624

RESUMO

PURPOSE: To identify the vascular patterns found in superficial lymph nodes with histologically confirmed lymphomatous involvement and to determine their value in the sonographic diagnosis of lymphadenopathy. METHODS AND MATERIALS: The study involved the prospective classification of vascular patterns observed during power Doppler and/or color Doppler studies of superficial lymph nodes scheduled for resection. Forty patients (27 men and 13 women, aged 22-84 years; mean age: 58 years) with pathologically proven lymphoma were selected for this study (26 cervical, 13 axillary and 1 inguinal). RESULTS: A longitudinal vessel with or without branches (pattern I) was found in 14 lymphomatous nodes. Six contained short vessel segments distributed in the hilum area or centrally (pattern II), five had multiple vessels, partially branching, entering the node in a few rows from its longitudinal side (pattern III), seven presented multiple vessels that branched irregularly or chaotically with avascular areas (pattern IV), and eight had a peripheral vessel distribution (pattern V). Therefore, 50% of the lymphomatous nodes had vascular patterns regarded as characteristic of reactive lymph nodes (patterns I and II), and 37.5% had patterns normally described in lymph nodes with metastatic involvement (patterns IV and V); other lymphomatous lymph nodes had ambiguous vascular patterns that have not been previously classified (pattern III). CONCLUSION: The angioarchitecture of superficial lymphomatous lymph nodes varies widely and is difficult to classify. It may resemble that reported in normal or reactive lymph nodes or patterns that are associated with metastases. The finding of a normal or benign vascular pattern in a lymph node with suspected lymphomatous involvement does not eliminate the need for a diagnostic biopsy.

3.
Radiology ; 219(2): 541-4, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11323485

RESUMO

PURPOSE: To determine the safety and reliability of the mechanical detachment system of a platinum coil (Detach-18) when used for neurovascular embolization. MATERIALS AND METHODS: Sixty patients (21 men, 39 women; age range, 26-75 years; mean age, 56.2 years) were treated in seven centers. Ease of introduction of the coil to the microcatheter, effect of coil passage on the microcatheter shape and stability during its delivery, retrievability of the coil before and after the transition zone passed beyond the microcatheter, detachment of the coil, and effect of coil rotation on the microcatheter stability were evaluated. The detachment system itself was evaluated for premature detachment, failure of the coil to detach, detachment time, number of turns, visibility of radiopaque markers, number of coils deployed per patient, and percentage of vessel occlusion obtained. A 0.015-inch-diameter regular coil and a 0.014-inch-diameter soft coil were used. RESULTS: A total of 1,061 coils were used; 1,009 were detached. The number of coils deployed ranged from four to 104 (mean, 17 coils). The coils passed easily through the microcatheter. The detachment maneuver occurred within 5-25 seconds, with five to 60 turns of the introducing wire. One premature coil detachment occurred without clinical sequela; 100% occlusion of the vessel lumen was achieved in 53 patients; 80%-90%, in four; and 70%-80%, in two. There were no device-related complications. CONCLUSION: The detachment system was safe and reliable. This is a useful system for coil embolization in neurovascular diseases.


Assuntos
Malformações Arteriovenosas/terapia , Malformações Vasculares do Sistema Nervoso Central/terapia , Embolização Terapêutica/instrumentação , Aneurisma Intracraniano/terapia , Adulto , Idoso , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pescoço/irrigação sanguínea , Platina , Radiografia , Segurança
4.
AJNR Am J Neuroradiol ; 22(2): 341-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11156780

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to determine the safety and reliability of the mechanical detachment system of a new platinum coil, Detach-18, when used as a vascular occlusive device for neurovascular disease. METHODS: Forty-one patients (nine male and 32 female patients; age range, 26-75 years; mean age, 54.4 years) underwent treatment at seven centers. Twenty-two patients had dural arteriovenous fistulae of the transverse sinus treated by a transvenous route. Fourteen patients underwent internal carotid artery occlusion in the treatment of aneurysms, meningioma, facial tumor, or carotid injury. One patient underwent occlusion of the basilar artery and one patient underwent occlusion of the vertebral artery for treatment of aneurysms. In two patients, coils were used as part of the treatment of their arteriovenous malformations. In all cases, the Detach-18 coils were delivered through a microcatheter with two distal markers. Two types of coils, a 0.015-inch-diameter "regular" coil and a 0.014-inch-diameter "soft" coil, were used. RESULTS: A total of 569 coils were used, 541 of which were detached. The number of coils in ranged from four to 53 (average number of coils, 14). The coils passed easily through the microcatheter. The detachment maneuver occurred within 10 to 25 s with 20 turns of the introducing wire. No premature coil detachment occurred. Complete occlusion of the vessel lumen was achieved in 35 cases. In three cases, 80% to 90% occlusion was achieved. In two cases, 70% to 80% occlusion was achieved. There were no device-related complications. CONCLUSION: The detachment system was safe, reliable, consistent, and fast. This is a useful system for coil embolization in neurovascular applications.


Assuntos
Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Platina , Adulto , Idoso , Artéria Carótida Interna , Angiografia Cerebral , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/terapia , Embolização Terapêutica/efeitos adversos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia
5.
AJNR Am J Neuroradiol ; 21(2): 386-90, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10696028

RESUMO

BACKGROUND AND PURPOSE: Several recent studies have shown that sonographic contrast agents may affect transcranial Doppler evaluation of the arterial peak systolic velocity (PSV). Some investigators reported an increase in PSV, and others reported no change in PSV compared with baseline values. This study was conducted to determine the effect of sonographic contrast agent on PSV measured in normal middle cerebral arteries. METHODS: Continuous spectral Doppler sonography was performed on the right middle cerebral artery of 20 participants with angiographically proven normal intracranial vasculature. Videotaping was performed in each case from the initiation of the administration of contrast medium until the effect of the contrast agent on the PSV subsided. The PSV values were normalized for each participant, were pooled, and were plotted as a function of time. RESULTS: PSV increased in all participants after the administration of contrast material; the mean maximum increase was 24+/-7.4% (mean +/- standard deviation) (range, 15-36%). The mean duration of PSV increase was 320+/-97 s (range, 165-465 s). CONCLUSION: The middle cerebral artery PSV increased substantially after the administration of contrast material. This effect needs to be considered if velocity thresholds developed for disease detection without the use of contrast materials are used when contrast agents are administered.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Meios de Contraste , Aumento da Imagem , Artéria Cerebral Média/diagnóstico por imagem , Polissacarídeos , Sístole/fisiologia , Ultrassonografia Doppler Transcraniana , Adolescente , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Meios de Contraste/farmacologia , Feminino , Análise de Fourier , Humanos , Masculino , Pessoa de Meia-Idade , Polissacarídeos/farmacologia , Sístole/efeitos dos fármacos
7.
Acad Radiol ; 6(11): 656-64, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10894068

RESUMO

RATIONALE AND OBJECTIVES: The authors attempted to determine the frequency and severity of adverse reactions to gadolinium-based magnetic resonance (MR) contrast agents and to identify strategies for management of patients at increased risk. MATERIALS AND METHODS: American Society of Neuroradiology program directors were surveyed about adverse reactions at their institutions to gadolinium-based contrast agents, the contrast agents responsible, and the management of patients with allergy-like reactions to iodinated or gadolinium-based agents who required MR contrast agent administration. RESULTS: Fifty-three (50.5%) surveys were received from 105 centers. Of 687,255 gadopentetate dimeglumine injections, 314 (0.046%) nonallergic reactions and 107 (0.016%) mild, 28 (0.004%) moderate, and five (0.001%) severe allergy-like reactions occurred. Of 74,275 gadodiamide injections, 11 (0.015%) nonallergic and 12 (0.016%) mild allergy-like reactions occurred. Of 64,005 gadoteridol administrations, 171 (0.267%) nonallergic reactions and 49 (0.077%) mild, 29 (0.047%) moderate, and 11 (0.017%) severe allergy-like reactions occurred. Twenty-six departments took no precautions for patients with previous allergy-like reactions to iodinated contrast material. Nineteen did not premedicate patients who previously had reactions to gadolinium-based agents before repeat administration of MR contrast agents. CONCLUSION: Although MR contrast agents are safe, adverse reactions occur. Many centers have not adopted policies for the OFF


Assuntos
Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Imageamento por Ressonância Magnética , Coleta de Dados , Hipersensibilidade a Drogas/etiologia , Hipersensibilidade a Drogas/prevenção & controle , Hipersensibilidade a Drogas/terapia , Gadolínio DTPA/efeitos adversos , Compostos Heterocíclicos/efeitos adversos , Humanos , Compostos Organometálicos/efeitos adversos , Fatores de Risco
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