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1.
Spinal Cord ; 53(4): 265-77, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25665542

RESUMO

OBJECTIVES: To develop a comprehensive set of common data elements (CDEs), data definitions, case report forms and guidelines for use in spinal cord injury (SCI) clinical research, as part of the CDE project at the National Institute of Neurological Disorders and Stroke (NINDS) of the US National Institutes of Health. SETTING: International Working Groups. METHODS: Nine working groups composed of international experts reviewed existing CDEs and instruments, created new elements when needed and provided recommendations for SCI clinical research. The project was carried out in collaboration with and cross-referenced to development of the International Spinal Cord Society (ISCoS) International SCI Data Sets. The recommendations were compiled, subjected to internal review and posted online for external public comment. The final version was reviewed by all working groups and the NINDS CDE team before release. RESULTS: The NINDS SCI CDEs and supporting documents are publically available on the NINDS CDE website and the ISCoS website. The CDEs span the continuum of SCI care and the full range of domains of the International Classification of Functioning, Disability and Health. CONCLUSION: Widespread use of CDEs can facilitate SCI clinical research and trial design, data sharing and retrospective analyses. Continued international collaboration will enable consistent data collection and reporting, and will help ensure that the data elements are updated, reviewed and broadcast as additional evidence is obtained.


Assuntos
Estudos Clínicos como Assunto , Elementos de Dados Comuns , Projetos de Pesquisa , Traumatismos da Medula Espinal , Acesso à Informação , Consenso , Humanos , Internet , National Institute of Neurological Disorders and Stroke (USA) , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Estados Unidos
2.
AJNR Am J Neuroradiol ; 44(11): 1242-1248, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37652578

RESUMO

In this review, concepts of algorithmic bias and fairness are defined qualitatively and mathematically. Illustrative examples are given of what can go wrong when unintended bias or unfairness in algorithmic development occurs. The importance of explainability, accountability, and transparency with respect to artificial intelligence algorithm development and clinical deployment is discussed. These are grounded in the concept of "primum no nocere" (first, do no harm). Steps to mitigate unfairness and bias in task definition, data collection, model definition, training, testing, deployment, and feedback are provided. Discussions on the implementation of fairness criteria that maximize benefit and minimize unfairness and harm to neuroradiology patients will be provided, including suggestions for neuroradiologists to consider as artificial intelligence algorithms gain acceptance into neuroradiology practice and become incorporated into routine clinical workflow.


Assuntos
Algoritmos , Inteligência Artificial , Humanos , Radiologistas , Fluxo de Trabalho
3.
AJNR Am J Neuroradiol ; 42(1): 206-210, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33184070

RESUMO

BACKGROUND AND PURPOSE: Prior research has shown substantial shifts in procedure shares between specialty groups providing lumbar punctures. Our aim was to analyze national trends in lumbar punctures among the Medicare population from 2010 to 2018. MATERIALS AND METHODS: Medicare Part B Physician/Supplier Procedure Summary Master Files from 2010 to 2018 were analyzed for all Current Procedural Terminology, Version 4 codes related to lumbar punctures (62270 and 62272). Lumbar puncture procedure volume and utilization rates were assessed and stratified by place of service and specialty background of the providers. RESULTS: From 2010 to 2018, the overall number of lumbar puncture procedures essentially has not changed (92,579 versus 92,533). Radiologists hold the largest and an increasing procedure share of diagnostic and overall lumbar punctures (overall share, 45.7% in 2010 [n = 42,296] versus 52.3% in 2018 [n = 48,414]). Advanced practice providers have increased their procedure share (3.7% in 2010 [n = 3388] versus 8.4% in 2018 [n = 7785], + 129.8% procedure volume). Emergency medicine physicians and neurologists have a decreasing procedure share (21.8% versus 15.3% and 12.5% versus 8.8%, respectively). The inpatient hospital setting remains the largest place of service for lumbar punctures, recording a 5.3% increase in procedure share. The emergency department lumbar puncture volume has declined, with a 7.4% decrease in the overall procedure share. Similarly, the hospital outpatient department procedure volume has increased (+4%), while the private office volume has decreased (-1.7%). CONCLUSIONS: During the past decade, lumbar puncture procedures among the Medicare population have remained stable, with a shift in procedure volume from the emergency department and private offices to the hospital setting, which has mainly affected radiologists and advanced practice providers.


Assuntos
Radiologistas , Punção Espinal/tendências , Serviço Hospitalar de Emergência/estatística & dados numéricos , Serviço Hospitalar de Emergência/tendências , Feminino , Hospitais/estatística & dados numéricos , Hospitais/tendências , Humanos , Masculino , Medicare , Radiologistas/estatística & dados numéricos , Estados Unidos
4.
AJNR Am J Neuroradiol ; 42(9): 1727-1734, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34326104

RESUMO

BACKGROUND AND PURPOSE: Multi-parametric MRI, provides a variety of biomarkers sensitive to white matter integrity, However, spinal cord MRI data in pediatrics is rare compared to adults. The purpose of this work was 3-fold: 1) to develop a processing pipeline for atlas-based generation of the typically developing pediatric spinal cord WM tracts, 2) to derive atlas-based normative values of the DTI indices for various WM pathways, and 3) to investigate age-related changes in the obtained normative DTI indices along the extracted tracts. MATERIALS AND METHODS: DTI scans of 30 typically developing subjects (age range, 6-16 years) were acquired on a 3T MR imaging scanner. The data were registered to the PAM50 template in the Spinal Cord Toolbox. Next, the DTI indices for various WM regions were extracted at a single section centered at the C3 vertebral body in all the 30 subjects. Finally, an ANOVA test was performed to examine the effects of the following: 1) laterality, 2) functionality, and 3) age, with DTI-derived indices in 34 extracted WM regions. RESULTS: A postprocessing pipeline was developed and validated to delineate pediatric spinal cord WM tracts. The results of ANOVA on fractional anisotropy values showed no effect for laterality (P = .72) but an effect for functionality (P < .001) when comparing the 30 primary WM labels. There was a significant (P < .05) effect of age and maturity of the left spinothalamic tract on mean diffusivity, radial diffusivity, and axial diffusivity values. CONCLUSIONS: The proposed automated pipeline in this study incorporates unique postprocessing steps followed by template registration and quantification of DTI metrics using atlas-based regions. This method eliminates the need for manual ROI analysis of WM tracts and, therefore, increases the accuracy and speed of the measurements.


Assuntos
Pediatria , Substância Branca , Adolescente , Adulto , Anisotropia , Criança , Imagem de Tensor de Difusão , Humanos , Medula Espinal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
5.
AJNR Am J Neuroradiol ; 42(4): 787-793, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33574102

RESUMO

BACKGROUND AND PURPOSE: The National Institute of Neurological Disorders and Stroke common data elements initiative was created to provide a consistent method for recording and reporting observations related to neurologic diseases in clinical trials. The purpose of this study is to validate the subset of common data elements related to MR imaging evaluation of acute spinal cord injury. MATERIALS AND METHODS: Thirty-five cervical and thoracic MR imaging studies of patients with acute spinal cord injury were evaluated independently in 2 rounds by 5 expert reviewers. Intra- and interrater agreement were calculated for 17 distinct MR imaging observations related to spinal cord injury. These included ordinal, categoric, and continuous measures related to the length and location of spinal cord hemorrhage and edema as well as spinal canal and cord measurements. Level of agreement was calculated using the interclass correlation coefficient and kappa. RESULTS: The ordinal common data elements spinal cord injury elements for lesion center and rostral or caudal extent of edema or hemorrhage demonstrated agreement ranging from interclass correlation coefficient 0.68 to 0.99. Reproducibility ranged from 0.95 to 1.00. Moderate agreement was observed for absolute length of hemorrhage and edema (0.54 to 0.60) with good reproducibility (0.78 to 0.83). Agreement for the Brain and Spinal Injury Center score showed the lowest interrater agreement with an overall kappa of 0.27 (0.20, 0.34). For 7 of the 8 variables related to spinal cord injury, agreement improved between the first and second evaluation. Continuous diameter measures of the spinal cord and spinal canal using interclass correlation coefficient varied substantially (0.23 to 0.83). CONCLUSIONS: Agreement was more consistent for the ordinal measures of spinal cord injury than continuous measures. Good to excellent agreement on length and location of spinal cord hemorrhage and edema can be achieved with ordinal measures alone.


Assuntos
Elementos de Dados Comuns , Traumatismos da Medula Espinal , Vértebras Cervicais , Humanos , Imageamento por Ressonância Magnética , National Institute of Neurological Disorders and Stroke (USA) , Reprodutibilidade dos Testes , Medula Espinal , Traumatismos da Medula Espinal/diagnóstico por imagem , Estados Unidos/epidemiologia
6.
AJNR Am J Neuroradiol ; 41(7): 1149-1155, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32616575

RESUMO

The appropriate imaging of patients with headache presents a number of important and vexing challenges for clinicians. Despite a number of guidelines and studies demonstrating a lack of cost-effectiveness, clinicians continue to image patients with chronic nonfocal headaches, and the trend toward imaging is increasing. The reasons are complex and include the fear of missing a clinically significant lesion and litigation, habitual and standard of care practices, lack of tort reform, regulatory penalties and potential impact on one's professional reputation, patient pressures, and financial motivation. Regulatory and legislative reforms are needed to encourage best practices without fear of professional sanctions when following the guidelines. The value of negative findings on imaging tests requires better understanding because they appear to provide some measure of societal value. Clinical decision support tools and machine intelligence may offer additional guidance and improve quality and cost-efficient management of this challenging patient population.


Assuntos
Cefaleia/diagnóstico por imagem , Neuroimagem , Análise Custo-Benefício , Humanos , Neuroimagem/economia , Neuroimagem/métodos
7.
AJNR Am J Neuroradiol ; 41(8): E52-E59, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32732276

RESUMO

Fueled by new techniques, computational tools, and broader availability of imaging data, artificial intelligence has the potential to transform the practice of neuroradiology. The recent exponential increase in publications related to artificial intelligence and the central focus on artificial intelligence at recent professional and scientific radiology meetings underscores the importance. There is growing momentum behind leveraging artificial intelligence techniques to improve workflow and diagnosis and treatment and to enhance the value of quantitative imaging techniques. This article explores the reasons why neuroradiologists should care about the investments in new artificial intelligence applications, highlights current activities and the roles neuroradiologists are playing, and renders a few predictions regarding the near future of artificial intelligence in neuroradiology.


Assuntos
Inteligência Artificial/tendências , Neurologia/métodos , Neurologia/tendências , Radiologia/métodos , Radiologia/tendências , Humanos
8.
AJNR Am J Neuroradiol ; 40(1): 14-18, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30237302

RESUMO

The American Society of Neuroradiology has teamed up with the American College of Radiology and the Radiological Society of North America to create a catalog of neuroradiology common data elements that addresses specific clinical use cases. Fundamentally, a common data element is a question, concept, measurement, or feature with a set of controlled responses. This could be a measurement, subjective assessment, or ordinal value. Common data elements can be both machine- and human-generated. Rather than redesigning neuroradiology reporting, the goal is to establish the minimum number of "essential" concepts that should be in a report to address a clinical question. As medicine shifts toward value-based service compensation methodologies, there will be an even greater need to benchmark quality care and allow peer-to-peer comparisons in all specialties. Many government programs are now focusing on these measures, the most recent being the Merit-Based Incentive Payment System and the Medicare Access Children's Health Insurance Program Reauthorization Act of 2015. Standardized or structured reporting is advocated as one method of assessing radiology report quality, and common data elements are a means for expressing these concepts. Incorporating common data elements into clinical practice fosters a number of very useful downstream processes including establishing benchmarks for quality-assurance programs, ensuring more accurate billing, improving communication to providers and patients, participating in public health initiatives, creating comparative effectiveness research, and providing classifiers for machine learning. Generalized adoption of the recommended common data elements in clinical practice will provide the means to collect and compare imaging report data from multiple institutions locally, regionally, and even nationally, to establish quality benchmarks.


Assuntos
Elementos de Dados Comuns/normas , Neurologia/métodos , Neurologia/normas , Radiologia/métodos , Radiologia/normas , Humanos , América do Norte , Estados Unidos
9.
AJNR Am J Neuroradiol ; 39(8): 1555-1561, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29903926

RESUMO

BACKGROUND AND PURPOSE: The zonally magnified oblique multislice EPI (ZOOM-EPI) diffusion-weighted sequence has been visually shown to provide superior MR diffusion image quality compared with the full-FOV single-shot EPI sequence (non-ZOOM-EPI) in the adult cervical spinal cord. The purpose of this study was to examine the diffusion tensor imaging indices in the normal human cervical spinal cord between ZOOMED and non-ZOOMED DTI acquisitions and determine whether DTI values are comparable between direct and indirect age-matched groups. MATERIALS AND METHODS: Fifty-four subjects 23-58 years of age (9 direct age-matched and 45 indirect age-matched) were scanned using a 1.5T scanner. Diffusion tensor indices including fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity were generated from the DTI dataset. These DTI values were calculated for both ZOOM and non-ZOOM acquisitions and compared at each intervertebral disc level. The variability of the DTI values for ZOOM and non-ZOOM sequences was measured using a coefficient of variation within direct and indirect age-matched controls. RESULTS: The mean diffusivity, axial diffusivity, and radial diffusivity values obtained along the cervical spinal cord in the age-matched controls showed a significant decrease using the ZOOM sequence (P = .05, P = .002, and P < .001). Mean fractional anisotropy showed a significant increase (P = .04) using the ZOOM sequence. The indirect age-matched controls showed a statistically significant increase in fractional anisotropy (P = .03) and a decrease in mean diffusivity (P = .002), axial diffusivity (P < .001), and radial diffusivity (P = .002) using the ZOOM sequence. Less variability has been shown in DTI using the ZOOM sequence compared with the non-ZOOM sequence in both direct and indirect age groups. The ZOOM sequence exhibited higher SNR (SNRZOOM = 22.84 ± 7.59) compared with the non-ZOOM sequence (SNRnon-ZOOM = 19.7 ± 7.05). However, when we used a 2-tailed t test assuming unequal variances, the ZOOM sequence did not demonstrate a statistically significant increase. CONCLUSIONS: ZOOM DTI acquisition methods provide superior image quality and precision over non-ZOOM techniques and are recommended over conventional full-FOV single-shot EPI DTI for clinical applications in cervical spinal cord imaging.


Assuntos
Medula Cervical/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Neuroimagem/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
AJNR Am J Neuroradiol ; 38(6): 1252-1256, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28385883

RESUMO

BACKGROUND AND PURPOSE: More than 75 million Americans have less than adequate health literacy skills according to the National Center for Education Statistics. Readability scores are used as a measure of how well populations read and understand patient education materials. The purpose of this study was to assess the readability of Web sites dedicated to patient education for radiologic spine imaging and interventions. MATERIALS AND METHODS: Eleven search terms relevant to radiologic spine imaging were searched on the public Internet, and the top 10 links for each term were collected and analyzed to determine readability scores by using 10 well-validated quantitative readability assessments from patient-centered education Web sites. The search terms included the following: x-ray spine, CT spine, MR imaging spine, lumbar puncture, kyphoplasty, vertebroplasty, discogram, myelogram, cervical spine, thoracic spine, and lumbar spine. RESULTS: Collectively, the 110 articles were written at an 11.3 grade level (grade range, 7.1-16.9). None of the articles were written at the American Medical Association and National Institutes of Health recommended 3rd-to-7th grade reading levels. The vertebroplasty articles were written at a statistically significant (P < .05) more advanced level than the articles for x-ray spine, CT spine, and MR imaging spine. CONCLUSIONS: Increasing use of the Internet to obtain health information has made it imperative that on-line patient education be written for easy comprehension by the average American. However, given the discordance between readability scores of the articles and the American Medical Association and National Institutes of Health recommended guidelines, it is likely that many patients do not fully benefit from these resources.


Assuntos
Relações Médico-Paciente , Radiologistas , Coluna Vertebral/diagnóstico por imagem , Comunicação , Compreensão , Escolaridade , Educação em Saúde , Letramento em Saúde , Humanos , Internet , Imageamento por Ressonância Magnética , Neurocirurgia , Pacientes , Leitura , Coluna Vertebral/cirurgia , Tomografia Computadorizada por Raios X
11.
AJNR Am J Neuroradiol ; 27(5): 1016-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16687535

RESUMO

BK virus infection is most often associated with urologic disease in patients who have undergone renal or bone marrow transplantation. We report a rare case of biopsy-confirmed BK virus encephalitis in an immunocompromised patient with hemorrhagic cystitis, in whom dramatic imaging findings were present despite relatively mild clinical symptoms. MR imaging demonstrated widespread increased signal intensity on T2- and fluid-attenuated inversion recovery-weighted images, with restricted diffusion, in the cerebellum, cerebral white matter, and deep gray matter structures. The simultaneous presence of urologic abnormalities and neurologic deficits in certain immunocompromised patients should prompt consideration of BK virus encephalitis.


Assuntos
Vírus BK , Encefalite Viral/diagnóstico , Imageamento por Ressonância Magnética , Infecções por Polyomavirus/diagnóstico , Infecções Tumorais por Vírus/diagnóstico , Adulto , Feminino , Humanos
12.
J Clin Oncol ; 19(8): 2189-200, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11304771

RESUMO

PURPOSE: Preclinical animal experiments support the use of an antisense oligodeoxynucleotide directed against the insulin-like growth factor type I receptor (IGF-IR/AS ODN) as an effective potential antitumor agent. We performed a human pilot safety and feasibility study using an IGF-IR/AS ODN strategy in patients with malignant astrocytoma. PATIENTS AND METHODS: Autologous glioma cells collected at surgery were treated ex vivo with an IGF-IR/AS ODN, encapsulated in diffusion chambers, reimplanted in the rectus sheath within 24 hours of craniotomy, and retrieved after a 24-hour in situ incubation. Serial posttreatment assessments included clinical examination, laboratory studies, and magnetic resonance imaging scans. RESULTS: Other than deep venous thrombosis noted in some patients, no other treatment-related side effects were observed. IGF-IR/AS ODN-treated cells, when retrieved and assessed, were < or = 2% intact by trypan blue exclusion, and none of the intact cells were viable in culture thereafter. Parallel Western blots disclosed IGF-IR downregulation to < or = 10% after ex vivo antisense treatment. At follow-up, clinical and radiographic improvements were observed in eight of 12 patients, including three cases of distal recurrence with unexpected spontaneous or postsurgical regression at either the primary or the distant intracranial site. CONCLUSION: Ex vivo IGF-IR/AS ODN treatment of autologous glioma cells induces apoptosis and a host response in vivo without unusual side effects. Subsequent transient and sustained radiographic and clinical improvements warrant further clinical investigations.


Assuntos
Apoptose , Astrocitoma/terapia , Neoplasias Encefálicas/terapia , Terapia Genética , Fator de Crescimento Insulin-Like I/farmacologia , Oligodesoxirribonucleotídeos Antissenso/uso terapêutico , Receptores de Somatomedina/fisiologia , Adulto , Feminino , Humanos , Fator de Crescimento Insulin-Like I/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Receptores de Somatomedina/genética , Resultado do Tratamento , Células Tumorais Cultivadas , Trombose Venosa/etiologia
13.
Arch Ophthalmol ; 112(3): 340-8, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8129659

RESUMO

OBJECTIVE: Recent studies have shown that contrast (gadopentetate dimeglumine)-enhanced magnetic resonance imaging is useful in evaluating intraocular tumors and differentiating uveal melanoma from other simulating lesions. The purpose of this study was to study prospectively the role of fat-suppression technique and gadopentetate dimeglumine-enhanced magnetic resonance imaging in the evaluation of intraocular neoplasia. PATIENTS: Forty-three uveal melanomas and 20 other simulating intraocular lesions from 63 patients were prospectively evaluated on non-contrast-enhanced and post-contrast-enhanced T1-weighted images with and without fat-suppression technique and on T2-weighted images. RESULTS: Forty-one uveal melanomas (95%) were detected with standard pulse sequences and showed the characteristic hyperintense signal on non-contrast-enhanced T1-weighted images and hypointense signal with respect to the vitreous on T2-weighted images. All 33 uveal melanomas evaluated on non-contrast-enhanced T1-weighted images with fat-suppression technique were detected on non-contrast-enhanced images with fat-suppression technique. The intensity of the signal was statistically associated with the degree of pigmentation of the tumor on T1-weighted images with fat-suppression technique (P = .03). On post-contrast-enhanced T1-weighted images with or without fat-suppression technique, the 43 uveal melanomas showed enhancement. The degree of tumor enhancement was not statistically related to the degree of tumor pigmentation or the location of the tumor. Among the other simulating intraocular lesions, choroidal metastasis, retinoblastoma, choroidal leiomyoma, and medulloepithelioma demonstrated the same features on magnetic resonance imaging studies as uveal melanoma demonstrated on non-contrast-enhanced and post-contrast-enhanced T1-weighted images with or without fat-suppression technique. In our series, choroidal hemangioma, choroidal osteoma, posterior scleritis, retinal hemangioma, and Coats' disease can be differentiated from other amelanotic intraocular tumors by their characteristics on magnetic resonance imaging studies. CONCLUSIONS: We concluded that pre-and post-contrast-enhanced T1-weighted images with fat-suppression technique are most helpful in detecting small intraocular tumors with a thickness of more than 1.8 mm and in evaluating intraocular neoplasms and simulating lesions, particularly when T2-weighted images are not available. Moreover, in juxtapapillary choroidal or retinal tumor, fat-suppression technique may help in the detection of possible optic nerve or orbital extension by improving the conspicuousness of the tumor.


Assuntos
Tecido Adiposo/anatomia & histologia , Neoplasias Oculares/diagnóstico , Gadolínio , Imageamento por Ressonância Magnética/métodos , Meglumina , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Meios de Contraste , Combinação de Medicamentos , Estudos de Avaliação como Assunto , Feminino , Gadolínio DTPA , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Retinoblastoma/diagnóstico , Neoplasias Uveais/diagnóstico
14.
AJNR Am J Neuroradiol ; 13(1): 283-6, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1595460

RESUMO

We report three cases that reveal an array of etiologic and radiologic findings associated with dissection of the proximal segment of the vertebral arteries. Regardless of etiology, the proximal segment may be the principal site of dissection in these vessels.


Assuntos
Dissecção Aórtica/etiologia , Quiroprática , Síndrome Medular Lateral/complicações , Artéria Vertebral , Adulto , Dissecção Aórtica/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
15.
AJNR Am J Neuroradiol ; 15(6): 1181-3, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8073992

RESUMO

MR appearance of two patients with large, orbital conjunctival epithelium-lined inclusion cysts are presented. Both were complications of ophthalmic surgical procedures that necessitated conjunctival incision.


Assuntos
Doenças da Túnica Conjuntiva/etiologia , Cisto Epidérmico/etiologia , Enucleação Ocular , Recurvamento da Esclera , Adolescente , Idoso , Doenças da Túnica Conjuntiva/diagnóstico , Cisto Epidérmico/diagnóstico , Neoplasias Oculares/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/diagnóstico , Retinoblastoma/cirurgia
17.
AJNR Am J Neuroradiol ; 12(5): 819-26; discussion 827-8, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1950904

RESUMO

We retrospectively reviewed the routine spin-echo MR studies of the brain in 12 patients with 13 angiographically demonstrated occlusions and in 14 patients with 16 high-grade stenoses of the carotid arteries. Intraluminal signal that was isointense with adjacent brain on long TR/short TE and long TR/long TE images was 100% specific for atherosclerotic occlusion. Of the 13 proved occlusions, six (46%) had significant degrees of hyperintense intraluminal signal indistinguishable from that observed consequent to slow flow distal to high-grade stenoses. MR detected only five (31%) of the 16 proved high-grade stenoses. Normal flow void does not exclude significant extracranial carotid stenosis. Occlusion cannot always be distinguished from high-grade stenosis when hyperintense intraluminal signal is encountered. However, a reliable diagnosis of atherosclerotic occlusion can be made when isointense intraluminal signal is observed.


Assuntos
Encéfalo/patologia , Artérias Carótidas/patologia , Imageamento por Ressonância Magnética , Grau de Desobstrução Vascular , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Angiografia Cerebral , Transtornos Cerebrovasculares/diagnóstico , Constrição Patológica , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Valores de Referência
18.
AJNR Am J Neuroradiol ; 20(5): 926-34, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10369368

RESUMO

BACKGROUND AND PURPOSE: The appearance of the damaged spinal cord after injury correlates with initial neurologic deficit, as determined by the American Spinal Injury Association grade and manual muscle test score, as well as with recovery, as assessed by manual muscle test scores. The purpose of this study was to determine whether the presence of spinal cord hemorrhage and the size and location of spinal cord edema on MR images is predictive of functional recovery in survivors of cervical spinal cord injury (SCI). METHODS: The degree of damage to the cervical spinal cord was measured on the MR images of 49 patients who underwent imaging within 72 hours of sustaining SCI. The effects of hemorrhage and length/location of edema on changes in the value of the motor scale of the functional independence measure (FIM) were assessed on admission to and discharge from rehabilitation. RESULTS: Patients without spinal cord hemorrhage had significant improvement in self-care and mobility scores compared with patients with hemorrhage. There was no significant effect of spinal cord hemorrhage on changes in locomotion and sphincter control scores. The rostral limit of edema positively correlated with admission and discharge self-care scores and with admission mobility and locomotion scores. Edema length had a negative correlation with all FIM scales at admission and discharge. CONCLUSION: The imaging characteristics of cervical SCI (hemorrhage and edema) are related to levels of physical recovery as determined by the FIM scale. Imaging factors that correlate with poor functional recovery are hemorrhage, long segments of edema, and high cervical locations.


Assuntos
Atividades Cotidianas , Imageamento por Ressonância Magnética , Traumatismos da Medula Espinal/diagnóstico , Medula Espinal/patologia , Adolescente , Adulto , Idoso , Cognição , Edema/diagnóstico , Feminino , Hemorragia/diagnóstico , Humanos , Locomoção , Masculino , Pessoa de Meia-Idade , Prognóstico , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia
19.
AJNR Am J Neuroradiol ; 22(9): 1768-74, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11673177

RESUMO

BACKGROUND AND PURPOSE: Although research with functional MR imaging of the brain has proliferated over the past 5 years, technical limitations, such as motion, chemical shift, and susceptibility artifacts, have impeded such research in the human spinal cord. The purpose of this investigation was to determine whether a reliable functional MR imaging signal can be elicited from the cervical spinal cord during simple motor activity. METHODS: Subjects performed three different motor tasks that activate different segments of the spinal cord. Gradient-echo-planar imaging on a 1.5-T clinical unit was used to image cervical spinal cords of human subjects. Another group of subjects was imaged while performing isometric exercise to study the relationship between the blood oxygenation level-dependent (BOLD) signal and applied force. RESULTS: Task-dependent BOLD activity was detected in all subjects. Signal amplitude varied between 0.5% and 7%. Moreover, a linear relationship was found between the applied force and the signal amplitude during isometric exercise. While regions of activation were distributed throughout the spinal cord, concentrated activity was found in the anatomic locations of expected motor innervation. CONCLUSION: The functional MR imaging signal can be reliably detected with motor activity in the human cervical spinal cord on a 1.5-T clinical unit. The location of neural activation has an anatomic correspondence to the myotome in use. The strength of the BOLD signal is directly proportional to the level of muscular activity.


Assuntos
Imageamento por Ressonância Magnética , Medula Espinal/anatomia & histologia , Medula Espinal/fisiologia , Vértebras Cervicais , Humanos
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