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1.
Br J Neurosurg ; : 1-6, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431732

RESUMO

PURPOSE: Lynch Syndrome (LS) is a cancer-predisposing condition resulting from hereditary mutation of DNA mismatch repair genes. Gastrointestinal, urogenital, and endometrial carcinomas are well-known to predominantly occur in LS patients. In contrast, there are only few reports on brain tumours in the context of LS and to date intracranial tumour manifestation appear to be rather coincidental. METHODS: We present the case of a 56-year-old female developing aggressive lactotroph pituitary adenoma following a history of multiple Lynch-associated malignomas and having a confirmed MSH2 mutation. Furthermore, we performed a literature review via PubMed using the search terms 'Lynch Syndrome', 'HNPCC', 'MMR mutation' combined with 'intracranial tumour', 'sellar tumour', 'pituitary adenoma', or 'pituitary carcinoma', focusing on other reported cases and treatment regimens. RESULTS: A handful of studies have indicated an increased frequency of brain tumours in the context of LS, predominantly glioblastoma and less frequently low-grade glioma or other brain tumours. Based on our literature review, we summarized the known instances of pituitary adenoma in LS patients, including the present case. Furthermore, we reviewed the common recommendation of using temozolomide (TMZ) for treatment of aggressive pituitary adenoma or carcinoma and found strong indication that it might be insufficient in LS patients, while PD-1 blockade could be a promising treatment option. CONCLUSIONS: Combined with our case, there is a growing body of evidence that intracranial tumours and in particular those of the sellar region might be more prevalent in LS patients than previously assumed, due to their genetic profile substantially affecting viability and efficacy of treatment options. Clinical signs of aggressive tumour growth in combination with irresponsiveness to standard treatment in case of recurrence should lead to further diagnostic measures, because revelation of germline MMR mutations would call for an extended screening for other neoplastic manifestations and would markedly influence further treatment.

2.
J Neuropathol Exp Neurol ; 77(11): 993-996, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299484

RESUMO

We report a case of a rapidly progressing, relapsing-remitting, steroid-responsive granulocytic encephalitis without any signs of peripheral nervous system or other organ involvement. It apparently had an immune-mediated etiology that could not be attributed to any known disease entity. A 22-year-old man presented with rapidly progressive severe neurological symptoms caused by encephalitis. Examination of the cerebrospinal fluid as well as brain biopsy showed extensive accumulation of neutrophilic granulocytes with no hints of an infectious agent. Magnetic resonance imaging revealed multiple T2/FLAIR demarcated lesions. Subsequent to a steroid pulse therapy, the clinical symptoms and imaging abnormalities improved rapidly. Ten months later, the patient experienced a disease relapse, which again responded well to steroids. Forty months after the relapse, he is currently doing well on azathioprine. This case highlights that an immunosuppressive treatment should be considered in patients with extensive neutrophilic encephalitis when no infectious agent is detected. A new immune-mediated relapsing-remitting CNS disease entity might need to be considered.


Assuntos
Encefalite/tratamento farmacológico , Imunossupressores/uso terapêutico , Esteroides/uso terapêutico , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Encefalite/complicações , Encefalite/diagnóstico por imagem , Encefalite/patologia , Hemorragia/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Infiltração de Neutrófilos/fisiologia , Recidiva , Adulto Jovem
4.
J Neurol ; 264(2): 341-349, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27909801

RESUMO

Diagnostic imaging criteria of multiple sclerosis (MS) include the spatial and temporal dissemination of cerebral and/or spinal cord lesions. Magnetic resonance imaging (MRI) is the method of choice for initial diagnosis and follow-up disease monitoring. Current guidelines for spinal MRI recommend sagittal imaging of the spinal cord and lesion confirmation on axial planes if lesions are detected. Sagittal imaging is, however, hampered by technical (e.g. partial volume effects, motion artifacts) and anatomical (e.g. scoliosis) limitations. We hypothesized that long coverage of the spinal cord by axial image acquisition has superior diagnostic performance compared to sagittal imaging and can identify otherwise undetected lesions. Our prospective clinical study included 119 MS patients. Axial MRI revealed ~2.5-fold more lesions than the sagittal angulation (axial lesion load: 4.0 ± 2.4 vs. 1.6 ± 1.2 lesions on sagittal planes, p < 0.001). Importantly, 20 patients (17%) with normal sagittal MRI scans had unequivocal lesions only visible on axial planes (mean lesion number on axial planes in these patients: 2.0 ± 1.3). Moreover, 45 patients (38%) showed a discrepancy of ≥3 lesions that were found additionally on axial scans (mean difference 4.4 ± 1.7). Additionally identified lesions were on average smaller in size and located more laterally within the spinal cord. No lesion on sagittal images was missed on the axial angulation. Our study demonstrates that imaging of small axial segments for lesion confirmation is insufficient in spinal imaging. We recommend implementing a long coverage axial MRI sequence for spinal imaging of MS patients.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Medula Espinal/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Avaliação da Deficiência , Feminino , Gadolínio , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
5.
Neuroradiology ; 58(9): 911-20, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27230917

RESUMO

INTRODUCTION: Professional boxing can lead to chronic traumatic encephalopathy, a variant of traumatic brain injury (TBI). Its occurrence in amateur boxers is a matter of debate since amateur boxing is considered to be less harmful due to more strict regulations. However, several studies using different methodological approaches have revealed subtle signs of TBI even in amateurs. Diffusion tensor imaging (DTI) is sensitive to microscopic white matter changes and has been proven useful in TBI when routine MR imaging often is unrevealing. METHODS: DTI, with tract-based spatial statistics (TBSS) together with neuropsychological examination of executive functions and memory, was used to investigate a collective of 31 male amateur boxers and 31 age-matched controls as well as a subgroup of 19 individuals, respectively, who were additionally matched for intellectual performance (IQ). RESULTS: All participants had normal findings in neurological examination and conventional MR. Amateur boxers did not show deficits in neuropsychological tests when their IQ was taken into account. Fractional anisotropy was significantly reduced, while diffusivity measures were increased along central white matter tracts in the boxers group. These changes were in part associated with the number of fights. CONCLUSIONS: TBSS revealed widespread white matter disturbance partially related to the individual fighting history in amateur boxers. These findings closely resemble those in patients with accidental TBI and indicate similar histological changes in amateur boxers.


Assuntos
Boxe/lesões , Encéfalo/patologia , Encefalopatia Traumática Crônica/patologia , Imagem de Tensor de Difusão/métodos , Leucoencefalopatias/patologia , Substância Branca/patologia , Adulto , Encéfalo/diagnóstico por imagem , Encefalopatia Traumática Crônica/diagnóstico por imagem , Humanos , Leucoencefalopatias/diagnóstico por imagem , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Substância Branca/diagnóstico por imagem
7.
J Neuroradiol ; 41(4): 259-68, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24411522

RESUMO

BACKGROUND AND PURPOSE: CT angiography (CTA) is an increasingly used method for evaluation of stented vessel segments. Our aim was to compare the appearance of different carotid artery stents in vitro on CTA using different CT scanners. Of particular interest was the measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether CTA can be used to detect in-stent restenosis. MATERIAL AND METHODS: CTA appearances of 16 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. CTA was performed using 16-, 64- and 320-row CT scanners. For each stent, artificial lumen narrowing (ALN) was calculated. RESULTS: ALN ranged from 18.77% to 59.86%. ALN in different stents differed significantly. In most stents, ALN decreased with increasing stent diameter. In all but one stents, ALN using sharp image kernels was significantly lower than ALN using medium image kernels. Considering all stents, ALN did not significantly differ using different CT scanners or imaging protocols. CONCLUSION: CTA evaluation of vessel patency after stent placement is possible, but is considerably impaired by ALN. Investigators should be informed about the method of choice for every stent and stent manufacturers should be aware of potential artifacts caused by their stents during noninvasive diagnostic methods such as CTA.


Assuntos
Angiografia/instrumentação , Prótese Vascular/efeitos adversos , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Oclusão de Enxerto Vascular/diagnóstico por imagem , Stents/efeitos adversos , Tomografia Computadorizada por Raios X/instrumentação , Angiografia/métodos , Artérias Carótidas/cirurgia , Doenças das Artérias Carótidas/etiologia , Desenho de Equipamento , Análise de Falha de Equipamento , Oclusão de Enxerto Vascular/etiologia , Técnicas In Vitro , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
8.
J Neuroradiol ; 40(5): 348-54, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23660542

RESUMO

BACKGROUND AND PURPOSE: Our aim was to evaluate the in vitro visualization of different carotid artery stents on Angiographic CT (ACT). Of particular interest was the measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether ACT can be used to detect restenosis within the stent. MATERIAL AND METHODS: ACT appearances of 17 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. All stents were imaged on two different angiography systems. For each stent, artificial lumen narrowing (ALN) was calculated. RESULTS: The ALN on the two different angiography systems did not significantly differ. With standard algorithm image reconstruction, ALN ranged from 19.1 to 46.6%. With stent-optimized algorithm image reconstruction, ALN was significantly lower and ranged from 7.6 to 17.2%. Different stents showed significantly different degree of ALN. Stent struts could be visualized in all stents. CONCLUSION: In our in vitro model, ACT evaluation of vessel patency after stent placement is possible but is impaired by ALN. Stent-optimized algorithm image reconstruction decreases ALN but further research is required to define the visibility of in-stent stenosis depending on image reconstruction.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Angiografia Cerebral/instrumentação , Stents/efeitos adversos , Tomografia Computadorizada por Raios X/instrumentação , Estenose das Carótidas/complicações , Desenho de Equipamento , Análise de Falha de Equipamento , Oclusão de Enxerto Vascular , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Neuroradiology ; 55(6): 675-82, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23411716

RESUMO

INTRODUCTION: Our aim was to evaluate the in vitro visualization of different carotid artery stents on angiographic CT (ACT). Of particular interest was the influence of stent orientation to the angiography system by measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether ACT can be used to detect restenosis within the stent. METHODS: ACT appearances of 17 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. Stents were placed in different orientations to the angiography system. Standard algorithm image reconstruction and stent-optimized algorithm image reconstruction was performed. For each stent, ALN was calculated. RESULTS: With standard algorithm image reconstruction, ALN ranged from 19.0 to 43.6 %. With stent-optimized algorithm image reconstruction, ALN was significantly lower and ranged from 8.2 to 18.7 %. Stent struts could be visualized in all stents. Differences in ALN between the different stent orientations to the angiography system were not significant. CONCLUSION: ACT evaluation of vessel patency after stent placement is possible but is impaired by ALN. Stent orientation of the stents to the angiography system did not significantly influence ALN. Stent-optimized algorithm image reconstruction decreases ALN but further research is required to define the visibility of in-stent stenosis depending on image reconstruction.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Intensificação de Imagem Radiográfica/métodos , Stents/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Angiografia/instrumentação , Angiografia/métodos , Estenose das Carótidas/complicações , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Imagens de Fantasmas , Implantação de Prótese/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/instrumentação , Resultado do Tratamento
10.
Int J Stroke ; 7(4): 282-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22151607

RESUMO

AIMS: We analyzed early diffusion-weighted magnetic resonance imaging of patients with acute basilar artery occlusion by applying different lesion scoring systems and determined their predictive value for favorable outcome. METHODS: Between 1998 and 2010, patients with confirmed basilar artery occlusion were entered in a local database. magnetic resonance imaging angiography was performed for diagnosis of basilar artery occlusion and/or during initiated recanalization therapy. We analyzed the patients' clinical and radiological baseline data, recanalization, and favorable outcome modified Rankin Scale 0-2 after three-months. Diffusion weighted imaging findings were categorized into lesions in vascular territories as well as by two previously published scores for ischemic damage in the posterior circulation, the Renard score and posterior circulation Acute Stroke Prognosis Early computed tomography Score. RESULTS: Fifty patients with basilar artery occlusion received an early MRI, and in 30 of those, a follow-up MRI was performed. Median time to baseline MRI was 5·5 h (one-hour to 24 h). Median baseline Renard score and posterior circulation Acute Stroke Prognosis Early CT Score were 2·75 (0-10) and 7 (0-10), respectively. Of the patients, 82% received an acute recanalization therapy and in 78% of those, the basilar artery recanalized. Median time to therapy was five-hours (1·25-20 h). 24% of all patients had a favorable outcome (mRS 0-2). Patients with a favorable outcome had a lower Renard score and higher pcASPECTS, a lower rate of complete basilar artery occlusion, a higher Glasgow coma scale on admission, and a higher rate of successful recanalization (all P < 0·05). After logistic regression, the only independent predictor for favorable outcome was a posterior circulation Acute Stroke Prognosis Early CT Score of 8 or more points (odds ratio 3·9, 95% confidence interval 1·4-11·7, P < 0·05). CONCLUSION: In patients with acute basilar artery occlusion, posterior circulation Acute Stroke Prognosis Early CT Score of 8 or more points on early diffusion weighted imaging is an independent predictor for favorable outcome.


Assuntos
Arteriopatias Oclusivas/patologia , Artéria Basilar/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/terapia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reperfusão , Índice de Gravidade de Doença , Terapia Trombolítica/métodos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
11.
Br J Neurosurg ; 25(1): 117-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20707682

RESUMO

This study presents a case of bifrontal intracerebral haemorrhage in a patient with heparin-induced thrombocytopenia type II (HIT II). HIT II was induced by treatment with low-molecular-weight heparin for recurrent deep vein thrombosis caused by essential thrombocytosis and accompanied by hepatic thromboembolism. This patient was treated with platelet substitution and neurosurgical haematoma evacuation. Anticoagulation with 2500 units danaparoid per day was sufficient for therapy of thrombosis and no rebleeding occurred.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Hemorragia Cerebral/tratamento farmacológico , Sulfatos de Condroitina/administração & dosagem , Dermatan Sulfato/administração & dosagem , Heparina de Baixo Peso Molecular/efeitos adversos , Heparitina Sulfato/administração & dosagem , Idoso , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , Quebra Cromossômica , Transtornos Cromossômicos/induzido quimicamente , Transtornos Cromossômicos/tratamento farmacológico , Humanos , Masculino , Trombocitopenia/induzido quimicamente , Trombocitopenia/congênito , Trombocitopenia/tratamento farmacológico , Resultado do Tratamento
12.
Neuroradiology ; 52(3): 231-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19844699

RESUMO

The endovascular treatment of wide-necked aneurysms remains challenging. The "Y"-stenting technique has been used for stent-assisted coil embolization of wide-necked bifurcation aneurysms. So far, this technique has been described for aneurysms of the basilar apex or the middle cerebral artery bifurcation and only for open stent systems using the Neuroform stent. We report a 52-year-old woman with recurrence of a wide-necked aneurysm of the anterior cerebral artery that was successfully retreated by stent-assisted coiling using the "Y"-stenting technique with the Enterprise stent system.


Assuntos
Artéria Cerebral Anterior , Doenças Arteriais Cerebrais/terapia , Embolização Terapêutica/instrumentação , Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Stents , Artéria Cerebral Anterior/patologia , Angiografia Cerebral , Doenças Arteriais Cerebrais/patologia , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/patologia , Angiografia por Ressonância Magnética , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Neuroradiology ; 52(9): 823-30, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19924409

RESUMO

INTRODUCTION: CT angiography (CTA) and MR angiography (MRA) are increasingly used methods for evaluation of stented vessel segments. The purpose of this study was to compare CTA, contrast-enhanced MRA (CEMRA) at 1.5 T, and CEMRA at 3 T for the visualization of carotid artery stents and to define the best noninvasive imaging technique for each stent. METHODS: CTA and CEMRA appearances of 18 carotid artery stents of different designs and sizes (4.0 to 10.0 mm) were investigated in vitro. The profile of the contrast-to-noise ratio (CNR) of the lumen of each stent was calculated semiautomatically by a pixel-by-pixel analysis using the medical imaging software OSIRIS. For each stent, artificial lumen narrowing (ALN) was calculated. RESULTS: In all but one stents, ALN was lower on CEMRA at 3 T than at 1.5 T. With CEMRA at 3 T and at 1.5 T, ALN in most nitinol stents was lower than in the groups of stainless steel and cobalt alloy stents. In most nitinol stents, ALN on CEMRA at 3 T was lower than on CTA. In all stainless steel stents and cobalt alloy stents, ALN was lower on CTA than on CEMRA. With CTA and CEMRA, in most stents ALN decreased with increasing stent diameter. CONCLUSION: CTA and CEMRA evaluation of vessel patency after stent placement is possible, but considerably impaired by ALN. Investigators should be informed about the method of choice for every stent.


Assuntos
Prótese Vascular , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Artérias Carótidas/cirurgia , Meios de Contraste , Análise de Falha de Equipamento/métodos , Humanos
14.
Z Med Phys ; 19(4): 278-87, 2009.
Artigo em Alemão | MEDLINE | ID: mdl-19995528

RESUMO

PURPOSE: The aim of this study was to qualitatively and quantitatively study MR artifacts of various stents on the basis of in vitro experiments. We were particularly interested whether sequence type and orientation of the stent with respect to the static magnetic field influences the artifact. MATERIAL AND METHODS: We examined 18 stents of different material (nitinol, stainless steel, cobalt alloy), different design of the stent meshes (AccuLink, OmniLink, DynaLink, Xact, Protoge, Wallstent Monorail), different diameter (5-10mm) and different length (18-58 mm) with a turbo spin echo (TSE), a 2D-fast low angle shot (FLASH) and a 3D-FLASH sequence. The MR images were examined qualitatively with respect to possible artifacts. Furthermore we examined the MR data quantitatively: The contrast-noise-ratio (CNR) was determined both within the stent and outside (within the tube); based on these values we calculated the transparency factor P, furthermore we calculated the apparent vascular lumen within the tube and within the stent. RESULTS: The stents made of stainless steel and cobalt alloy displayed severe susceptibility artifacts. Therefore the vessel lumen within the stent could not be assessed. The nitinol stents showed different artifact patterns: The AccuLink and DynaLink stents showed less artifacts compared to the Xact and Protoge stents. Besides the susceptibility artifacts we found artifacts due to RF shielding by the stent mesh, particularly in TSE sequences. CONCLUSION: A MR control of patients after stenting is possible and may yield diagnostic information when using the AccuLink or DynaLink stents. However, it is important to make sure that the stent is MR safe for the field strength used for the examination.


Assuntos
Artefatos , Imageamento por Ressonância Magnética/métodos , Stents , Desenho de Equipamento , Humanos , Stents/normas , Stents/estatística & dados numéricos
17.
Plast Reconstr Surg ; 119(3): 985-91, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17312505

RESUMO

BACKGROUND: Anterior craniofacial duplication (diprosopus) is an extremely rare form of conjoined twins. The children share a single trunk with normal extremities and varying degrees of facial malformation. Duplication of specific structures, such as the nose (diprosopus dirrhinus), eyes (diprosopus tetraophthalmus), and ears, is possible. The authors present a case of partial facial duplication (diprosopus dirrhinus) in a male infant. METHODS: The clinical and radiographic findings and the surgical correction and follow-up are described. RESULTS: In a single surgical session, the authors were able to achieve not only a functionally but also an aesthetically acceptable result. In the postoperative course, the child showed nearly normal growth and satisfactory psychosocial and motor development. However, 40 months postoperatively, we noticed a tendency of the orbitae to diverge (i.e., toward hypertelorism). CONCLUSIONS: The surgical management of complex craniofacial malformations such as diprosopus needs a precise morphologic analysis of the patient's deformity followed by a clear treatment plan. A staged reconstructive approach is carried out to coincide with facial growth patterns and brain and eye function. If the interorbital distance in our patient increases progressively, a second operation for reduction of the interorbital distance may be necessary.


Assuntos
Anormalidades Craniofaciais/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Ossos Faciais/anormalidades , Ossos Faciais/cirurgia , Humanos , Lactente , Masculino , Nariz/anormalidades , Nariz/cirurgia , Osteotomia
18.
Artigo em Inglês | MEDLINE | ID: mdl-17178507

RESUMO

OBJECTIVE: To determine if it is possible to measure age-related pulp cavity signal intensity changes by using magnetic resonance imaging (MRI). STUDY DESIGN: Dental pulp cavity signal intensities were assessed in 92 test subjects on the basis of MRI signal intensity measurements at freely defined regions of interest by using T1 gradient echo sequences before and after contrast-agent administration. Relative signal intensity differences were calculated and provided the basis for age- and tooth-related comparisons. RESULTS: Significant signal intensity differences were noted between the oldest (born between 1930 and 1959) and the youngest (born after 1980) test subjects and the other groups (P < .05). In addition, the first molars showed significantly lower signal intensity differences than the second molars (P < .05). CONCLUSION: Magnetic resonance imaging can be used to determine pulp cavity signal-intensity changes with age.


Assuntos
Dente Pré-Molar/fisiologia , Cavidade Pulpar/fisiologia , Teste da Polpa Dentária/métodos , Imageamento por Ressonância Magnética , Dente Molar/fisiologia , Fatores Etários , Humanos , Estudos Retrospectivos , Estatísticas não Paramétricas
19.
Pediatr Radiol ; 36(10): 1075-81, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16896692

RESUMO

BACKGROUND: MRI at 3.0 T enables high-spatial resolution for renal MR angiography. OBJECTIVE: Evaluation of an arterial tree model in animal kidney specimens with comparison of digital subtraction angiography (DSA) and high-field MRI to find out the maximum spatial resolution of intrarenal vessels. It was considered that objective quantitation of angiogram quality could be achieved. MATERIALS AND METHODS: A total of 27 pig kidney specimens were examined by MR angiography (flash 3D) using a 3.0-T scanner (TRIO; Siemens, Erlangen, Germany) with an eight-channel head coil and a voxel size of 0.9x0.9x1.1 mm in the early arterial phase after implantation of a 4F catheter in the renal artery. DSA (Integris, Philips, Best, The Netherlands) was performed immediately after the MRI. With the help of semiautomated segmentation, all vessels were marked for comparison of the vessel trees. The Wilcoxon rank test was used for statistical evaluation of vessel numbers and branching depths. RESULTS: Objective comparison between DSA and MR angiography was achieved. High-field MR angiography had the ability to depict vessels up to the seventh branching on average. Significant differences in vessel delineation and counts were found from the fifth level of intrarenal branching onwards with DSA showing an advantage. CONCLUSION: High-field MRI has great potential in the detection of intrarenal arteries and is comparable to DSA in visualization of the central intrarenal vessel tree.


Assuntos
Angiografia Digital , Rim/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Animais , Meios de Contraste , Gadolínio DTPA , Iohexol/análogos & derivados , Estatísticas não Paramétricas , Suínos
20.
Neuroradiology ; 48(7): 479-85, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16721557

RESUMO

INTRODUCTION: We assessed the technical feasibility of balloon-assisted angioplasty with consecutive stenting using a flexible, self-expanding neurovascular stent for the treatment of intracranial arteriosclerotic vascular stenoses. METHODS: Five consecutive patients with symptomatic drug-resistant stenoses of the intracranial internal carotid artery (ICA) or the main stem of the middle cerebral artery (MCA) were treated by balloon-assisted angioplasty with consecutive stenting using the Neuroform stent system. RESULTS: Balloon dilatation of the stenoses and consecutive stent placement with complete coverage of the stenoses was feasible in all patients. One patient suffered acute thrombosis distally to the stented vessel segment which was successfully treated by fibrinolysis, and one patient suffered acute subarachnoid and parenchymal hemorrhage probably due to vessel perforation. In the other three patients, no complications occurred during or immediately after angioplasty. All patients were free of further ischemic events up to the 6-month follow-up. CONCLUSION: Our findings demonstrate that the Neuroform stent system can used successfully for the treatment of intracranial stenoses of the ICA and the main stem of the MCA. Although immediate angiographic results are promising, long-term angiographic and clinical follow-up is essential to demonstrate long-term outcome.


Assuntos
Angioplastia com Balão/instrumentação , Artéria Carótida Interna , Estenose das Carótidas/terapia , Infarto da Artéria Cerebral Média/terapia , Stents , Idoso , Estenose das Carótidas/diagnóstico por imagem , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento
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