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1.
J Appl Gerontol ; 41(5): 1336-1347, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35085043

RESUMO

The number of falls among older adults is rising due to an aging population worldwide. An integrated communication campaign utilizing mHealth (mobile health) encouraged older adults to perform strength, balance, and flexibility exercises to reduce their risk of falling. Campaign development was guided by a mixed-method approach which incorporated expert interviews (N = 3), qualitative interviews (N = 22), and a quantitative baseline pre-campaign survey (N = 274) with older adults. We evaluated the campaign impact with a pre-post survey analysis (post n = 141). Impact was measured by knowledge, attitudes, self-efficacy, and behaviors as key Social Cognitive Theory factors to exercise adoption. Results showed that respondents with campaign exposure had a significant increase in all factor scores from pre- to post-campaign survey, which was significantly higher in the group with campaign exposure. The impact evaluation illustrated how digital mobile channels effectively provide means to reach older adults to reduce their risk of falling.


Assuntos
Acidentes por Quedas , Telemedicina , Acidentes por Quedas/prevenção & controle , Idoso , Exercício Físico , Terapia por Exercício/métodos , Humanos , Inquéritos e Questionários
2.
AJNR Am J Neuroradiol ; 38(7): 1443-1448, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28522662

RESUMO

BACKGROUND AND PURPOSE: Cytomegalovirus is the leading intrauterine infection. Fetal MR imaging is an accepted tool for fetal brain evaluation, yet it still lacks the ability to accurately predict the extent of the neurodevelopmental impairment, especially in fetal MR imaging scans with unremarkable findings. Our hypothesis was that intrauterine cytomegalovirus infection causes diffusional changes in fetal brains and that those changes may correlate with the severity of neurodevelopmental deficiencies. MATERIALS AND METHODS: A retrospective analysis was performed on 90 fetal MR imaging scans of cytomegalovirus-infected fetuses with unremarkable results and compared with a matched gestational age control group of 68 fetal head MR imaging scans. ADC values were measured and averaged in the frontal, parietal, occipital, and temporal lobes; basal ganglia; thalamus; and pons. For neurocognitive assessment, the Vineland Adaptive Behavior Scales, Second Edition (VABS-II) was used on 58 children in the cytomegalovirus-infected group. RESULTS: ADC values were reduced for the cytomegalovirus-infected fetuses in most brain areas studied. The VABS-II showed no trend for the major domains or the composite score of the VABS-II for the cytomegalovirus-infected children compared with the healthy population distribution. Some subdomains showed an association between ADC values and VABS-II scores. CONCLUSIONS: Cytomegalovirus infection causes diffuse reduction in ADC values in the fetal brain even in unremarkable fetal MR imaging scans. Cytomegalovirus-infected children with unremarkable fetal MR imaging scans do not deviate from the healthy population in the VABS-II neurocognitive assessment. ADC values were not correlated with VABS-II scores. However, the lack of clinical findings, as seen in most cytomegalovirus-infected fetuses, does not eliminate the possibility of future neurodevelopmental pathology.


Assuntos
Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Adaptação Psicológica , Adulto , Encéfalo/diagnóstico por imagem , Criança , Comportamento Infantil , Pré-Escolar , Infecções por Citomegalovirus/psicologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Lactente , Recém-Nascido , Testes Neuropsicológicos , Gravidez , Estudos Retrospectivos
3.
AJNR Am J Neuroradiol ; 36(3): E12-23, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25655872

RESUMO

The past decade has seen impressive advances in the types of neuroimaging information that can be acquired in patients with traumatic brain injury. However, despite this increase in information, understanding of the contribution of this information to prognostic accuracy and treatment pathways for patients is limited. Available techniques often allow us to infer the presence of microscopic changes indicative of alterations in physiology and function in brain tissue. However, because histologic confirmation is typically lacking, conclusions reached by using these techniques remain solely inferential in almost all cases. Hence, a need exists for validation of these techniques by using data from large population samples that are obtained in a uniform manner, analyzed according to well-accepted procedures, and correlated with closely monitored clinical outcomes. At present, many of these approaches remain confined to population-based research rather than diagnosis at an individual level, particularly with regard to traumatic brain injury that is mild or moderate in degree. A need and a priority exist for patient-centered tools that will allow advanced neuroimaging tools to be brought into clinical settings. One barrier to developing these tools is a lack of an age-, sex-, and comorbidities-stratified, sequence-specific, reference imaging data base that could provide a clear understanding of normal variations across populations. Such a data base would provide researchers and clinicians with the information necessary to develop computational tools for the patient-based interpretation of advanced neuroimaging studies in the clinical setting. The recent "Joint ASNR-ACR HII-ASFNR TBI Workshop: Bringing Advanced Neuroimaging for Traumatic Brain Injury into the Clinic" on May 23, 2014, in Montreal, Quebec, Canada, brought together neuroradiologists, neurologists, psychiatrists, neuropsychologists, neuroimaging scientists, members of the National Institute of Neurologic Disorders and Stroke, industry representatives, and other traumatic brain injury stakeholders to attempt to reach consensus on issues related to and develop consensus recommendations in terms of creating both a well-characterized normative data base of comprehensive imaging and ancillary data to serve as a reference for tools that will allow interpretation of advanced neuroimaging tests at an individual level of a patient with traumatic brain injury. The workshop involved discussions concerning the following: 1) designation of the policies and infrastructure needed for a normative data base, 2) principles for characterizing normal control subjects, and 3) standardizing research neuroimaging protocols for traumatic brain injury. The present article summarizes these recommendations and examines practical steps to achieve them.


Assuntos
Lesões Encefálicas , Bases de Dados Factuais , Neuroimagem , Lesões Encefálicas/patologia , Feminino , Humanos , Masculino
4.
AJNR Am J Neuroradiol ; 35(11): 2029, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25339648
6.
AJNR Am J Neuroradiol ; 35(4): 632-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23988754

RESUMO

SUMMARY: With rapid advances in neuroimaging technology, there is growing concern over potential misuse of neuroradiologic imaging data in legal matters. On December 7 and 8, 2012, a multidisciplinary consensus conference, Use and Abuse of Neuroimaging in the Courtroom, was held at Emory University in Atlanta, Georgia. Through this interactive forum, a highly select group of experts-including neuroradiologists, neurologists, forensic psychiatrists, neuropsychologists, neuroscientists, legal scholars, imaging statisticians, judges, practicing attorneys, and neuroethicists-discussed the complex issues involved in the use of neuroimaging data entered into legal evidence and for associated expert testimony. The specific contexts of criminal cases, child abuse, and head trauma were especially considered. The purpose of the conference was to inform the development of guidelines on expert testimony for the American Society of Neuroradiology and to provide principles for courts on the ethical use of neuroimaging data as evidence. This report summarizes the conference and resulting recommendations.


Assuntos
Prova Pericial/ética , Psiquiatria Legal/ética , Neurorradiografia/ética , Guias de Prática Clínica como Assunto , American Medical Association , Humanos , Estados Unidos
7.
Exp Mol Pathol ; 71(2): 137-46, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11599920

RESUMO

Piecemeal necrosis, currently called interface hepatitis, is a feature of viral hepatitis as well as autoimmune hepatitis and steatohepatitis. The mechanism of liver cell loss and piecemeal necrosis needs to be determined. We hypothesize that piecemeal necrosis in hepatitis is due to a piecemeal removal of hepatocyte cytoplasm by lymphocytic ingestion. To test this hypothesis, 61 consecutive liver biopsies were examined by light microscopy, by immunohistochemistry and by electron microscopy, and the lymphocytic-hepatocytic interaction was morphologically assessed. In cases of hepatitis C, hepatitis B, autoimmune hepatitis, primary biliary cirrhosis, and steatohepatitis, piecemeal necrosis was found. Using cytokeratin stains, it was apparent that the lymphocyte-hepatocyte interaction and piecemeal necrosis leads first to binding of the lymphocyte to hepatocyte plasma membrane and then blebbing or indentation of the hepatocyte by the lymphocyte, followed by endocytosis of liver cell cellular components and digestion in the lymphocyte lysosomes. This process is repeated while the cytoplasm and the nucleus of the hepatocyte disappear bite by bite, and only nubbins of residual hepatocytic cytoplasm remain, either attached to intact hepatocytes or surrounded and sequestered within scar tissue and lymphocytes. We conclude that piecemeal necrosis is a gradual disappearance of hepatocytes as a result of lymphocyte-hepatocyte binding and ligand internalization of liver surface molecules by the lymphocyte. This gradual process leads to a slow reduction of hepatocyte size and eventual disappearance at the interface between the lobule and portal tracts. To term this new kind of necrosis, we propose the name troxis necrosis, after the Greek noun meaning "nibbling."


Assuntos
Hepatócitos/patologia , Cirrose Hepática/patologia , Linfócitos/patologia , Biópsia , Morte Celular , Hepatite/metabolismo , Hepatite/patologia , Hepatócitos/metabolismo , Humanos , Técnicas Imunoenzimáticas , Queratinas/metabolismo , Cirrose Hepática/classificação , Linfócitos/metabolismo , Microscopia Eletrônica , Mitocôndrias/patologia
8.
Neuroimaging Clin N Am ; 11(1): viii, 111-29, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11331230

RESUMO

Spinal vascular malformations (AVMs) are rare but important causes of treatable myelopathies. Recent advances in the interventional neuroradiology and neurosurgical techniques have improved the delineation and classification of these heterogeneous lesions. Because MR imaging usually is the first screening test for patients with myelopathy, the neuroradiologist must have a high level of knowledge of the common imaging characteristics of these lesions. This article reviews MR angiographic literature about spinal AVMs, Type I-IV AVMs and cervical Type I AVMs, describes their pathophysiology and common imaging characteristics, and elaborates on differences in cervical location from more typical positions.


Assuntos
Malformações Arteriovenosas/patologia , Imageamento por Ressonância Magnética , Medula Espinal/irrigação sanguínea , Artérias/patologia , Malformações Arteriovenosas/diagnóstico , Vértebras Cervicais/patologia , Diagnóstico Diferencial , Humanos , Angiografia por Ressonância Magnética , Medula Espinal/patologia
10.
AJNR Am J Neuroradiol ; 21(9): 1650-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11039344

RESUMO

BACKGROUND AND PURPOSE: Postoperative contrast-enhanced MR imaging of the brain is routinely used when evaluating for residual or recurrent brain tumor. It is imperative to be aware of morphologic changes and imaging features that typically occur in response to surgical manipulation at the postoperative site to avoid misinterpretation of imaging findings. Our purpose was to determine normal postoperative changes and alterations in the choroid plexus among patients who had undergone temporal lobectomy in order to distinguish this appearance from pathologic changes that may be seen in the presence of infection or recurrent tumors. METHODS: We reviewed 159 MR scans from 95 patients with hippocampal sclerosis or gliosis who underwent temporal lobectomy for treatment of intractable epilepsy. Choroid plexus location and size were assessed on contrast-enhanced T1-weighted images. RESULTS: After temporal lobectomy, the choroid plexus enlarged and sagged into the resection site. Increase in the size of the choroid plexus occurred in 58% of cases overall. The degree of enhancement also increased after surgery, sometimes resulting in a nodular pattern of enhancement. The changes were most marked during the 1st week after temporal lobectomy, and showed an enlarged, markedly enhancing choroid plexus on 86% of the scans. CONCLUSION: Postoperative changes of the choroid plexus after temporal lobectomy include sagging into the resection site, an increased size, and an increased degree of enhancement. Normal postoperative morphologic characteristics may mimic neoplastic enhancement pattern. Familiarity with this appearance is important to avoid a pitfall in diagnosis of recurrent postoperative temporal lobe neoplasms.


Assuntos
Plexo Corióideo/patologia , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias , Lobo Temporal/cirurgia , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Criança , Meios de Contraste , Diagnóstico Diferencial , Gadolínio DTPA , Hipocampo/patologia , Humanos , Pessoa de Meia-Idade , Esclerose
11.
Magn Reson Imaging Clin N Am ; 8(3): 581-96, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947928

RESUMO

Spinal vascular malformations (AVMs) are rare but important causes of treatable myelopathies. Recent advances in interventional neuroradiolgy and neurosurgical techniques have improved the delineation and classifcation of these heterogeneous lesions. Because MR imaging usually is the first screening test for patients with myelopathy, the neuroradiologist must have a high level of knowledge of the common imaging characteristics of these lesions. This article reviews MR angiographic literature about spinal AVMs, reviews Type I-IV AVMs and cervical Type I AVMs, and describes their pathophysiology and common imaging characteristics, and elaborates on differences in cervical location from more typical positions.


Assuntos
Malformações Arteriovenosas/diagnóstico , Vértebras Cervicais , Imageamento por Ressonância Magnética/métodos , Medula Espinal/irrigação sanguínea , Humanos
12.
Invest Radiol ; 35(7): 412-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10901102

RESUMO

RATIONALE AND OBJECTIVES: The objective of the two pivotal phase 3 studies was to evaluate the safety and efficacy of OptiMARK (Gd-DTPA-bis(methoxyethylamide) [Gd-DTPA-BMEA]) compared with Magnevist (Gd-DTPA) in magnetic resonance imaging of the central nervous system. METHODS: Two multicenter, randomized, double-blind, parallel group studies were conducted in 395 patients with known or suspected central nervous system pathology. Subjects were randomized to receive a single 0.1 mmol/kg intravenous injection of either Gd-DTPA-BMEA or Gd-DTPA. The safety of Gd-DTPA-BMEA and Gd-DTPA was monitored for up to 72 hours after study drug administration. Precontrast and postcontrast administration magnetic resonance scans were acquired using identical imaging planes and techniques. RESULTS: No deaths or unexpected adverse events were reported in either group. A comparison of adverse events by intensity and relation demonstrated no statistically significant differences between the two groups. Gd-DTPA-BMEA and Gd-DTPA were equivalent with respect to confidence in diagnosis, conspicuity, and border delineation. CONCLUSIONS: Gd-DTPA-BMEA and Gd-DTPA demonstrated comparable efficacy profiles, and the safety profiles were considered similar.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Meios de Contraste , Gadolínio DTPA , Compostos Organometálicos , Adulto , Idoso , Encéfalo/patologia , Meios de Contraste/efeitos adversos , Método Duplo-Cego , Feminino , Gadolínio , Gadolínio DTPA/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/efeitos adversos , Medula Espinal/patologia
13.
Epilepsia ; 41(2): 148-57, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10691111

RESUMO

PURPOSE: Vigabatrin (Sabril, Hoechst Marion Roussel) is an antiepilepsy drug (AED) presently marketed in 64 countries for the treatment of partial and secondarily generalized seizures. Vigabatrin (VGB) is marketed in a subset of these countries for the treatment of infantile spasms. Clinical experience in humans has shown that VGB provides effective seizure control with a wide margin of safety. However, animal toxicity studies raised concern when prolonged administration of VGB was shown to induce intramyelinic edema (IME) in some laboratory animal species. METHODS: Animal and human data were reviewed with respect to the potential for VGB-induced IME. Surveillance of patients receiving VGB in clinical trials or by prescription has been conducted for >15 years to identify patients developing clinical abnormalities that might be IME related. RESULTS: The histologic lesions of VGB-induced IME in animals are reliably reproduced and correlate with changes in multimodality evoked potentials (EPs) and magnetic resonance imaging (MRI). Numerous studies of the effects of VGB on EP and MRI in epilepsy patients have demonstrated no clear-cut IME-related changes in these modalities. Additionally, autopsy and surgical brain samples from VGB-treated patients have been scrutinized for potential IME histopathology. In an estimated 350,000 patient-years of VGB exposure (approximately 175,000 patients exposed for 2 years at an average dose of 2 g/day), no definite case of VGB-induced IME has been identified. CONCLUSIONS: Comprehensive review of a variety of sources of data failed to identify any definite case of IME in humans treated with VGB.


Assuntos
Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/toxicidade , Edema/induzido quimicamente , Bainha de Mielina/efeitos dos fármacos , Vigabatrina/efeitos adversos , Vigabatrina/toxicidade , Animais , Anticonvulsivantes/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encefalopatias/induzido quimicamente , Encefalopatias/diagnóstico , Encefalopatias/patologia , Ensaios Clínicos como Assunto , Cães , Edema/diagnóstico , Edema/patologia , Epilepsia/tratamento farmacológico , Potenciais Evocados , Humanos , Imageamento por Ressonância Magnética , Bainha de Mielina/patologia , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/patologia , Vigilância de Produtos Comercializados , Ratos , Espasmos Infantis/tratamento farmacológico , Vigabatrina/farmacologia
14.
Radiology ; 215(1): 229-33, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10751491

RESUMO

PURPOSE: To describe parenchymal perianeurysmal cystic changes in the brain. MATERIALS AND METHODS: Among 247 patients with cerebral aneurysms described in the medical or radiologic records in three institutions, five had perianeurysmal cystic changes. These were evaluated with computed tomography or magnetic resonance (MR) imaging and were categorized according to size, appearance, and the presence of hemosiderin deposit. Confirmation at stereotactic needle biopsy was available in one case. RESULTS: Perianeurysmal cysts comprised multiple clustered cysts in three cases and a unilocular cyst in two, and diameters were 1.5-3.5 cm. Hemosiderin was depicted at MR imaging in one unilocular cyst. Associated aneurysms had diameters of 0.7-4.0 cm, and prominent aneurysmal thrombosis and calcifications were seen in two cases. Findings at stereotactic needle biopsy were of mild reactive gliosis. At long-term follow-up in two patients, the cystic regions were stable. CONCLUSION: Parenchymal perianeurysmal cysts are rare and may display various morphologic characteristics from unilocular to multilocular. Since there may or may not be evidence of previous hemorrhage, other mechanisms such as abnormal angiogenesis factors may play a role.


Assuntos
Encefalopatias/diagnóstico , Encéfalo/patologia , Cistos/diagnóstico , Aneurisma Intracraniano/diagnóstico , Adulto , Biópsia , Encefalopatias/patologia , Calcinose/diagnóstico , Angiografia Cerebral , Hemorragia Cerebral/diagnóstico , Cistos/patologia , Feminino , Seguimentos , Gliose/diagnóstico , Hemossiderina/análise , Humanos , Aneurisma Intracraniano/patologia , Trombose Intracraniana/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/diagnóstico , Estudos Retrospectivos , Técnicas Estereotáxicas , Tomografia Computadorizada por Raios X
17.
Am Surg ; 64(10): 986-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9764708

RESUMO

Obstruction is the presenting symptom of colorectal cancer in up to 40 per cent of patients. Benign strictures and other neoplasms including lymphoma and gynecologic tumors occur as well. Emergent operative therapy is often suboptimal and associated with significant morbidity and mortality. Our objective was to review our experience with stent placement for colonic obstruction. Seven patients underwent stent placement for a total of eight procedures. There were three patients with unresectable colorectal cancer, two patients with metastatic gynecologic cancer, one patient with rectal lymphoma, and one patient with metastatic cancer of unknown primary. All colonic stents were Wallstents placed by the same endoscopist under fluoroscopic and endoscopic guidance. Stents were successfully placed in all patients without complication. One patient underwent placement of two stents in succession for a long stenosis. Six of seven patients (86%) had resolution of the obstruction and return of bowel function. Five of seven were tolerating a diet within 24 hours. One patient's mental status did not allow for oral intake. Four patients were discharged within 48 hours. Two patients died within the same hospitalization as a result of metastatic disease. One patient was found to have multilevel disease requiring stoma placement. There was no morbidity or mortality associated with stent placement, and 86 per cent of patients had palliation of the obstruction. We conclude that colonic stent placement is a safe and effective therapy for colorectal obstruction at this institution.


Assuntos
Neoplasias Colorretais/terapia , Obstrução Intestinal/terapia , Stents , Neoplasias Colorretais/secundário , Nutrição Enteral , Feminino , Neoplasias dos Genitais Femininos/terapia , Humanos , Obstrução Intestinal/etiologia , Linfoma/terapia , Masculino , Neoplasias Primárias Desconhecidas/terapia , Cuidados Paliativos , Resultado do Tratamento
18.
Radiology ; 208(1): 129-36, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9646803

RESUMO

PURPOSE: To determine the frequency and characteristics of small cerebral aneurysms with atypical appearances on magnetic resonance (MR) images. MATERIALS AND METHODS: MR imaging studies (n = 117) obtained at 1.5 T of small aneurysms (< 1 cm diameter) were prospectively and retrospectively analyzed. Signal intensity characteristics and gadolinium-enhancement patterns in 84 aneurysms (62 patients) were evaluated. The patency of all aneurysms was confirmed at angiography or at the time of surgery. RESULTS: A characteristic signal void was seen on 62 (53%) of 117 studies. On the remaining 55 (47%) studies, aneurysms had atypical signal intensity that was isointense, heterogeneous, or hyperintense. Contrast-enhanced aneurysms were seen on 27 (53%) of 51 gadolinium-enhanced studies. CONCLUSION: Atypical MR imaging characteristics were seen in roughly half of cases. These atypical-appearing aneurysms may erroneously be considered to be thrombosed or be mistaken for other common lesions such as small tumors and be dismissed as nonvascular.


Assuntos
Aneurisma Intracraniano/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/diagnóstico , Angiografia Cerebral , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio DTPA , Humanos , Aumento da Imagem/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/cirurgia , Embolia e Trombose Intracraniana/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Grau de Desobstrução Vascular
19.
AJNR Am J Neuroradiol ; 19(5): 821-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9613494

RESUMO

PURPOSE: Although studies obtained with triple-dose contrast administration can show more brain metastases than those obtained with single-dose contrast material in patients with multiple metastases, such studies are costly and of limited clinical benefit. Since most patients who undergo screening have negative findings or a single metastasis, this study was performed to compare the clinical utility of single-dose versus triple-dose contrast administration in this large group of patients who could benefit from the possible increased sensitivity in lesion detection. METHODS: Ninety-two consecutive patients with negative or equivocal findings or a solitary metastasis on single-dose contrast-enhanced MR images underwent triple-dose studies. Findings were compared with a standard of reference composed of panel review and long-term follow-up. Further analysis was performed by comparing results with those obtained by two blinded readers. RESULTS: In all 70 negative single-dose studies, the triple-dose studies depicted no additional metastases in terms of the standard of reference. No statistically significant difference was seen between the results of the single- and triple-dose studies. For 10 equivocal single-dose studies, the triple-dose study helped clarify the presence or absence of metastases in 50% of the cases. In 12 patients with a solitary metastasis seen on the single-dose study, the triple-dose study depicted additional metastases in 25% of the cases. In the results of one of the two blinded readers, use of triple-dose contrast led to a statistical difference by decreasing the number of equivocal readings but at the expense of increasing the number of false-positive readings. CONCLUSION: Routine triple-dose contrast administration in all cases of suspected brain metastasis is not helpful. On the basis of our investigation, we conclude that the use of triple-dose contrast material is beneficial in selected cases with equivocal findings or solitary metastasis, although with the disadvantage of increasing the number of false-positive results.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/secundário , Meios de Contraste/administração & dosagem , Imageamento por Ressonância Magnética , Encéfalo/patologia , Relação Dose-Resposta a Droga , Reações Falso-Positivas , Humanos , Estudos Prospectivos , Método Simples-Cego
20.
Pediatr Neurol ; 18(3): 262-4, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9568926

RESUMO

Activated protein C resistance is the most common hereditary coagulation abnormality and is caused by the factor V Leiden mutation. A newborn who developed seizures within hours after delivery and was found to have a bihemispheric stroke is described. This patient, determined to be heterozygous for factor V Leiden, is the first reported case of neonatal stroke associated with this common mutation.


Assuntos
Transtornos Cerebrovasculares/genética , Fator V/genética , Heterozigoto , Humanos , Recém-Nascido , Masculino , Mutação , Tomografia Computadorizada por Raios X
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