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1.
Nursing ; 50(2): 24-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31904617

RESUMO

Historically, MRI was contraindicated in patients with cardiovascular implantable electronic devices because the devices' metallic components made this imaging study unsafe. Advances over the last decade have now made MRI safe for many of these patients. This article examines the risks of MRI technology for this patient population and reviews recent guidelines from the Heart Rhythm Society.


Assuntos
Desfibriladores Implantáveis , Imagem por Ressonância Magnética/normas , Marca-Passo Artificial , Segurança do Paciente/normas , Desfibriladores Implantáveis/efeitos adversos , Humanos , Imagem por Ressonância Magnética/efeitos adversos , Imagem por Ressonância Magnética/enfermagem , Marca-Passo Artificial/efeitos adversos
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 42-48, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31950788

RESUMO

Objective: To explore the value of a radiomics approach based on MRI texture analysis (TA) in identifying intraductal carcinoma of the prostate gland (IDCP). Methods: MRI images of 56 patients with pathological proven prostate cancer were analyzed retrospectively, including 31 patients with pure prostate adenocarcinoma and 25 patients with IDCP component in the prostate adenocarcinoma lesions. After imaging features of lesions were analyzed, then enhanced arterial and venous phase images were imported into Omni-Kinetics software for the extraction the TA features of region of interests' lesion according to the T2-weighted imaging. In order to set up a regression prediction model which based on texture parameters and morphological features. Furthermore, the comparison of diagnostic accuracy of each TA regression models were assessed by operating characteristic curves (ROC). Results: Among the imaging features of peripheral lesions, the incidence of surgical capsule invasion, prostatic capsule involvement, and seminal vesicle invasion in patients with IDCP was higher than that in patients with adenocarcinoma alone ( P<0.05). Among the imaging features of transitional zone lesions, patients with adenocarcinoma containing IDCP had a higher incience of imaging features as benign prostatic hyperplasia, extracapsular invasion of the prostate, seminal vesicles invasion, and vascular nerve bundles than that in pure adenocarcinoma group ( P<0.05). In order to differential diagnosis of simple adenocarcinoma and adenocarcinoma containing IDCP, 4 arterial phase texture features were used to build the regression model in the peripheral zone group, and the area under the curve ( AUC) of the TA model and combined model with or without seminal vesicles invasion were 0.890 and 0.938, respectively. In the transitional zone group, 2 arterial phase texture features and 2 venous phase features were used in TA regression model, and the AUC of texture model and the combined model with or without vascular nerve bundles were 0.844 and 0.901, respectively. Conclusion: The incidence of adenocarcinoma with IDCP is higher in high-grade invasive prostate cancer. It is wonderful that when compared with T2WI, enhanced sequential texture analysis is more valuable when using the radiomics approach based on MRI texture analysis in identifying IDCP in prostate cancer.


Assuntos
Carcinoma Intraductal não Infiltrante , Imagem por Ressonância Magnética , Neoplasias da Próstata , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/normas , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
3.
Radiol Med ; 125(1): 15-23, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31587182

RESUMO

OBJECTIVES: To evaluate the performance of the LI-RADS v.2018 scale by comparing it with the Likert scale, in the characterization of liver lesions. METHODS: A total of 39 patients with chronic liver disease underwent MR examination for characterization of 44 liver lesions. Images were independently analyzed by two radiologists using the LI-RADS scale and by another two radiologists using the Likert scale. The reference standard used was either histopathological evaluation or a 4-year MRI follow-up. Receiver operating characteristic analysis was performed. RESULTS: The LI-RADS scale obtained an accuracy of 80%, a sensitivity of 72%, a specificity of 93%, a positive predictive value (PPV) of 93% and a negative predictive value (NPV) of 70%, while the Likert scale achieved an accuracy of 79%, a sensitivity of 73%, a specificity of 87%, a PPV of 89% and a NPV of 70%. The area under the curve (AUC) was 85% for the LI-RADS scale and 83% for the Likert scale. The inter-observer agreement was strong (k = 0.89) between the LI-RADS evaluators and moderate (k = 0.69) between the Likert evaluators. CONCLUSIONS: There was no statistically significant difference between the performances of the two scales; nevertheless, we suggest that the LI-RADS scale be used, as it appeared more objective and consistent.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Lesões Pré-Cancerosas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Fígado/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Curva ROC , Padrões de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(4): 627-632, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31441264

RESUMO

The quality inspection of magnetic resonance imaging (MRI) performance parameters is an important means to ensure the image quality and the reliability of diagnosis results. There are some problems in the manual calculation and eye recognition of the quality inspection parameters, such as strong subjectivity and low efficiency. In view of these facts, an automatic analysis system for MRI quality detection based on QT is proposed and implemented in C++ language. The image processing algorithm is introduced to automatically measure and calculate the quality inspection parameters. The software with comprehensive functions is designed to systematically manage the quality inspection information of MRI. The experimental results show that the automatically calculated parameters are consistent with the manually calculated ones. Accordingly, the accuracy and reliability of the algorithm is verified. The whole system is efficient, convenient and easy to operate, and it can meet the actual needs of MRI quality inspection.


Assuntos
Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética/normas , Algoritmos , Reprodutibilidade dos Testes
5.
Br J Radiol ; 92(1103): 20190443, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31433668

RESUMO

MRI of articular cartilage (AC) integrity has potential to become a biomarker for osteoarthritis progression. Traditional MRI sequences evaluate AC morphology, allowing for the measurement of thickness and its change over time. In the last two decades, more advanced, dedicated MRI cartilage sequences have been developed aiming to assess AC matrix composition non-invasively and detect early changes in cartilage not captured on morphological sequences. T2-mapping and T1ρ sequences can be used to estimate the relaxation times of water inside the AC. These sequences have been introduced into clinical protocols and show promising results for cartilage assessment. Extracelullar matrix can also be assessed using diffusion-weighted imaging and diffusion tensor imaging as the movement of water is limited by the presence of extracellular matrix in AC. Specific techniques for glycosaminoglycans (GAG) evaluation, such as delayed gadolinium enhanced MRI of cartilage or Chemical Exchange Saturation Transfer imaging of GAG, as well as sodium imaging have also shown utility in the detection of AC damage. This manuscript provides an educational update on the physical principles behind advanced AC MRI techniques as well as a comprehensive review of the strengths and weaknesses of each approach. Current clinical applications and potential future applications of these techniques are also discussed.


Assuntos
Cartilagem Articular/fisiologia , Matriz Extracelular/fisiologia , Imagem por Ressonância Magnética/métodos , Meios de Contraste , Gadolínio , Glicosaminoglicanos/metabolismo , Humanos , Imagem por Ressonância Magnética/normas , Prognóstico , Sensibilidade e Especificidade , Sódio
6.
Cancer Radiother ; 23(6-7): 753-760, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31427076

RESUMO

Imaging provides the basis for radiotherapy. Multi-modality images are used for target delineation (primary tumor and nodes, boost volume) and organs at risk, treatment guidance, outcome prediction, and treatment assessment. Next to anatomical information, more and more functional imaging is being used. The current paper provides a brief overview of the different applications of imaging techniques used in the radiotherapy process, focusing on uncertainties and QA. The paper mainly focuses on PET and MRI, but also provides a short discussion on DCE-CT. A close collaboration between radiology, nuclear medicine and radiotherapy departments provides the key to improve the quality of radiotherapy. Jointly developed imaging protocols (RT position setup, immobilization tools, lasers, flat table…), and QA programs are mandatory. For PET, suitable windowing in consultation with a Nuclear Medicine Physician is crucial (differentiation benign/malignant lesions, artifacts…). A basic knowledge of MRI sequences is required, in such a way that geometrical distortions are easily recognized by all members the RT and RT physics team. If this is not the case, then the radiologist should be introduced systematically in the delineation process and multidisciplinary meetings need to be organized regularly. For each image modality and each image registration process, the associated uncertainties need to be determined and integrated in the PTV margin. When using functional information for dose painting, response assessment or outcome prediction, collaboration between the different departments is even more important. Limitations of imaging based biomarkers (specificity, sensitivity) should be known.


Assuntos
Imagem por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Garantia da Qualidade dos Cuidados de Saúde , Planejamento da Radioterapia Assistida por Computador/métodos , Incerteza , Artefatos , Humanos , Imagem por Ressonância Magnética/normas , Imagem Multimodal/normas , Estadiamento de Neoplasias , Neoplasias/patologia , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/normas , Tomografia Computadorizada por Raios X/métodos
7.
Medicine (Baltimore) ; 98(30): e16360, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31348236

RESUMO

BACKGROUND AND OBJECTIVE: Ischemic stroke is a foremost cause for disability and death worldwide. This study is conducted in order to compare the diagnostic values between transcranial Doppler ultrasound (ultrasonography), computed tomography (CT), and magnetic resonance imaging (MRI) in patients suffering from ischemic stroke by performing a network meta-analysis. METHODS: We made use of Cochrane Library, PubMed, and Embase in order to obtain literature and papers. The combination analysis of both direct and indirect evidence in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy was conducted so as to assess the odds ratios (ORs) and surface under the cumulative ranking curve (SUCRA) values of the seven different imaging methods. These imaging techniques include ultrasonography, computed tomography (traditional CT, computed tomography angiography [CTA], computed tomography perfusion [CTP]), and MRI (traditional MRI, diffusion-weighted imaging [DWI], magnetic resonance angiography), in order to properly diagnose ischemic stroke patients. RESULTS: Thirteen eligible diagnostic trials were enrolled into this network meta-analysis. The results of the traditional meta-analysis showed that among CT methods, CTP showed higher sensitivity, NPV, and accuracy; among MRI methods, DWI had relatively higher sensitivity, NPV, and accuracy. The results of network meta-analysis showed that DWI had relatively higher sensitivity, NPV, and accuracy when compared with traditional CT, CTA, magnetic resonance angiography and traditional MRI. CTP showed higher SUCRA among CT methods while DWI showed higher SUCRA among MRI methods. A cluster analysis revealed that DWI had the highest diagnostic value in terms of sensitivity, PPV, NPV, and accuracy amongst the aforementioned seven imaging techniques. CONCLUSION: This network meta-analysis provides supporting evidence to the idea that DWI has a higher diagnostic value regarding ischemic stroke among MRI methods, and CTP has a poor diagnostic value among CT methods, which provide therapeutic considerations for Ischemic stroke intervention.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler Transcraniana/métodos , Angiografia por Tomografia Computadorizada/métodos , Angiografia por Tomografia Computadorizada/normas , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/normas , Humanos , Angiografia por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/normas , Imagem por Ressonância Magnética/normas , Meta-Análise em Rede , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X/normas , Ultrassonografia Doppler Transcraniana/normas
8.
J Med Radiat Sci ; 66(3): 163-169, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31353806

RESUMO

INTRODUCTION: The objective of this study was to evaluate the effect on diagnostic image quality and acquisition time utilising a DIXON sequence to replace two standard proton density (PD) fat saturation (FS) sequences in routine magnetic resonance (MR) evaluation of the knee. METHODS: Thirty-one consecutive patients referred for an MR examination of the knee were examined using the routine departmental protocol along with the addition of a DIXON sequence. The sequences were all evaluated by a senior radiologist and feedback provided via both written and scored responses. The sequences were then repackaged for two additional reviewers with the sagittal PD FS (Chemical Shift Selective Fat Saturation or CHESS) and sagittal PD removed and replaced with the DIXON (fat suppressed and in-phase, respectively) sequence equivalents. Scored and written responses were tabled and reviewed to assess the suitability of sequence replacement. RESULTS: The DIXON-based images were judged as being comparable replacements for the sagittal PD fat sat and PD sequences. There was no report of any loss in diagnostic confidence across the 31 patients (total of 32 knees) with a time saving of just over 10% gained. The most common issues raised affecting image quality, though not affecting diagnostic attributes, were patient motion and a minor chemical shift artefact. CONCLUSION: The use of the DIXON technique in place of the PD sequences was of equivalent diagnostic quality with'good' to 'outstanding' fat suppression observed for the majority of cases using the DIXON sequence with an incremental time saving obtained.


Assuntos
Joelho/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Tecido Adiposo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/efeitos adversos , Imagem por Ressonância Magnética/normas , Auditoria Médica , Variações Dependentes do Observador
9.
Spine (Phila Pa 1976) ; 44(13): E766-E773, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31205169

RESUMO

STUDY DESIGN: Reliability study. OBJECTIVE: To evaluate the applicability and reliability of 9.4T magnetic resonance imaging (MRI) in the assessment of degenerative disc disease compared with 3T MRI. SUMMARY OF BACKGROUND DATA: MRI is a reliable indicator of biochemical changes in the intervertebral disc (IVD) including hydration status, proteoglycan content, and disc degeneration compared with anatomical and histological studies. High-field 9.4T MRI has been shown to provide superior resolution and anatomical detail. However, it has not been tested against current standard MRI techniques. METHODS: Disc degeneration was initiated in 36 skeletally mature ewes 6 months prior to necropsy via validated surgical IVD injury models using either scalpel injury or drill-bit injury techniques at lumbar spine levels L2/3 and L3/4 with L1/2, L4/5, and L5/6 serving as control discs. All ex vivo IVDs were examined with 9.4T MRI and 3T MRI. All scans were analyzed using the Pfirrmann grading system by four independent observers. Intra- and interobserver reliability was assessed using kappa statistics and Spearman correlation. RESULTS: Inter- and intraobserver agreement for 9.4T MRI was excellent, both at κ 0.91 (P < 0.001). Comparatively, 3T interobserver reliability demonstrated substantial agreement at κ 0.61 (P < 0.001). Complete agreement was obtained in 92.7% to 100% of discs at 9.4T compared with 69.7% to 83.1% at 3T. A difference of one grade or more occurred in 6.7% at 9.4T and 39.3% at 3T. 9.4T MRI scored 97.3% of discs as grade 1 to 2 compared with 71.3% at 3T. 3T MRI tended to over-score the extent of disc degeneration with 28.6% of discs scored as grade 3 or higher compared with 2.7% at 9.4T MRI. CONCLUSION: 9.4T MRI study of IVD degeneration using the Pfirrmann grading system demonstrated excellent inter- and intraobserver reliability. Comparatively, 3T MRI demonstrated a tendency to over score the extent of disc degeneration. This improved reliability of 9.4T MRI holds great potential for its clinical applications. LEVEL OF EVIDENCE: 3.


Assuntos
Degeneração do Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Animais , Biometria/métodos , Feminino , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/patologia , Imagem por Ressonância Magnética/métodos , Reprodutibilidade dos Testes , Ovinos
10.
PLoS Med ; 16(6): e1002813, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31158230

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) combined with targeted biopsy (TB) is increasingly used in men with clinically suspected prostate cancer (PCa), but the long acquisition times, high costs, and inter-center/reader variability of routine multiparametric prostate MRI limit its wider adoption. METHODS AND FINDINGS: The aim was to validate a previously developed unique MRI acquisition and reporting protocol, IMPROD biparametric MRI (bpMRI) (NCT01864135), in men with a clinical suspicion of PCa in a multi-institutional trial (NCT02241122). IMPROD bpMRI has average acquisition time of 15 minutes (no endorectal coil, no intravenous contrast use) and consists of T2-weighted imaging and 3 separate diffusion-weighed imaging acquisitions. Between February 1, 2015, and March 31, 2017, 364 men with a clinical suspicion of PCa were enrolled at 4 institutions in Finland. Men with an equivocal to high suspicion (IMPROD bpMRI Likert score 3-5) of PCa had 2 TBs of up to 2 lesions followed by a systematic biopsy (SB). Men with a low to very low suspicion (IMPROD bpMRI Likert score 1-2) had only SB. All data and protocols are freely available. The primary outcome of the trial was diagnostic accuracy-including overall accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value-of IMPROD bpMRI for clinically significant PCa (SPCa), which was defined as a Gleason score ≥ 3 + 4 (Gleason grade group 2 or higher). In total, 338 (338/364, 93%) prospectively enrolled men completed the trial. The accuracy and NPV of IMPROD bpMRI for SPCa were 70% (113/161) and 95% (71/75) (95% CI 87%-98%), respectively. Restricting the biopsy to men with equivocal to highly suspicious IMPROD bpMRI findings would have resulted in a 22% (75/338) reduction in the number of men undergoing biopsy while missing 4 (3%, 4/146) men with SPCa. The main limitation is uncertainty about the true PCa prevalence in the study cohort, since some of the men may have PCa despite having negative biopsy findings. CONCLUSIONS: IMPROD bpMRI demonstrated a high NPV for SPCa in men with a clinical suspicion of PCa in this prospective multi-institutional clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT02241122.


Assuntos
Imagem por Ressonância Magnética/normas , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/epidemiologia , Idoso , Finlândia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/normas , Estudos Prospectivos , Reprodutibilidade dos Testes
11.
Dev Cogn Neurosci ; 38: 100667, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31170550

RESUMO

The current study provides an overview of quantity and quality of MRI data in a large developmental twin sample (N = 512, aged 7-9), and investigated to what extent scan quantity and quality were influenced by genetic and environmental factors. This was examined in a fixed scan protocol consisting of two functional MRI tasks, high resolution structural anatomy (3DT1) and connectivity (DTI) scans, and a resting state scan. Overall, scan quantity was high (88% of participants completed all runs), while scan quality decreased with increasing session length. Scanner related distress was negatively associated with scan quantity (i.e., completed runs), but not with scan quality (i.e., included runs). In line with previous studies, behavioral genetic analyses showed that genetics explained part of the variation in head motion, with heritability estimates of 29% for framewise displacement and 65% for absolute displacement. Additionally, our results revealed that subtle head motion (after exclusion of excessive head motion) showed lower heritability estimates (0-14%), indicating that findings of motion-corrected and quality-controlled MRI data may be less confounded by genetic factors. These findings provide insights in factors contributing to scan quality in children, an issue that is highly relevant for the field of developmental neuroscience.


Assuntos
Encéfalo/diagnóstico por imagem , Confiabilidade dos Dados , Meio Ambiente , Movimentos da Cabeça , Imagem por Ressonância Magnética/normas , Gêmeos/genética , Artefatos , Encéfalo/fisiologia , Criança , Emoções/fisiologia , Feminino , Movimentos da Cabeça/fisiologia , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética/métodos , Masculino , Gêmeos/psicologia
12.
Brain Lang ; 195: 104642, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31238122

RESUMO

Research on structural brain differences between monolinguals and bilinguals remains inconsistent, and this has been proposed by some to be due in part to inadequate sample sizes. The aim of the present study is to reveal the expected degrees of uncertainty among neuroimaging findings by analyzing random samples of varying sizes from a larger-than-average sample. Bilinguals (n = 216) were compared with monolinguals (n = 146) using grey matter volume measures across region-of-interest tests. Variability among findings were compared with the true full-sample findings, and taken in the context of expected differences within the larger bilingualism neuroimaging literature. Results demonstrate excessive variability across the lowest sample sizes (e.g. samples totaling 20-80 participants), and this is explored through the trends of subsample outcomes and effect sizes across sample sizes. The results of this study illustrate the influences of power on expected variability among sample findings.


Assuntos
Imagem por Ressonância Magnética/métodos , Multilinguismo , Encéfalo/fisiologia , Feminino , Humanos , Imagem por Ressonância Magnética/normas , Masculino , Reprodutibilidade dos Testes , Tamanho da Amostra , Adulto Jovem
16.
J Orthop Surg Res ; 14(1): 152, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31126302

RESUMO

RATIONALE AND OBJECTIVES: The aim of this study was to investigate the efficacy of magnetic resonance imaging (MRI) with a spoiled gradient-recalled (SPGR) sequence to evaluate early knee cartilage degeneration and the relationship between cartilage and other tissues using a modified Whole-Organ Magnetic Resonance Imaging Score (WORMS). MATERIALS AND METHODS: Eighty-four patients with knee joint pain were evaluated by X-ray and MRI with an SPGR sequence from June 2015 to December 2016. Joint degeneration was graded by two experienced radiologists using the Kellgren-Lawrence (K-L) grading scale. The modified WORMS was used to evaluate cartilage lesions, bone marrow abnormalities, bone cysts, osteophytes, joint effusion and synovitis. The difference between the WORMS of the SPGR and the T2 sequences evaluated by the Wilcoxon signed-rank test was determined, and the relationships between the WORMS features were evaluated by a Spearman correlation. RESULTS: The modified WORMS for the cartilage lesion evaluation was significantly higher with the SPGR sequence than with the T2 sequence (P < 0.05). The cartilage lesions showed a moderate correlation with osteophytes, synovitis and joint effusion (Rs > 0.40, P < 0.05) and weak correlations with bone marrow abnormalities and bone cysts (Rs < 0.4, P < 0.05). CONCLUSION: The modified WORMS evaluation using MRI with the SPGR sequence was much better than the normal sequence for early knee osteoarthritis (OA). The cartilage lesions are associated with bone marrow abnormalities and the other features of OA.


Assuntos
Artralgia/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Adolescente , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
17.
J Pediatr Orthop ; 39(5): 268-274, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30969258

RESUMO

BACKGROUND: The management of septic arthritis of the hip in children can be complicated by the presence of additional coexisting periarticular infections (PAIs). Criteria predicting the presence of PAI have recently been proposed by Rosenfeld and colleagues with the goal of using magnetic resonance imaging (MRI) efficiently in the workup of septic arthritis. The purpose of this study was to determine the applicability of recently published predictive criteria for PAI (developed in the Southwestern United States using a variety of joints) to septic arthritis of the hip treated at a large Northeastern tertiary care center. METHODS: We studied patients treated for septic arthritis of the hip with irrigation and debridement in a large Northeastern tertiary care center over a 10-year period. Laboratory and clinical variables related to presentation, treatment, and outcome were collected. Subjects with and without a perioperative MRI were compared with published criteria by Rosenfeld and colleagues. RESULTS: Fifty-one subjects (53 hips) were identified with a mean age of 7.0 years (range, 1.2 to 19.3 y) and mean follow-up was 16 months (range, 2 to 85 mo). MRIs were obtained in 20 subjects (43%). Coexisting osteomyelitis was revealed in 7/20 of these studies (35% of MRIs); 4 of which showed coexisting intramuscular abscesses. Within our MRI cohort, the Rosenfeld criteria were found to have a sensitivity of 86%, a specificity of 54%, and a false-positive rate of 50% for the hip (compared with originally reported sensitivity of 90%, specificity of 67%, and false-positive rate of 33%). Overall, advanced imaging changed management in 5/51 patients (9%) by influencing the need for further treatment, whereas the remainder underwent isolated treatment of the septic hip joint with no adverse outcomes. One patient in the MRI cohort (without PAI) developed osteonecrosis of the femoral head. CONCLUSIONS: We found lower sensitivity and specificity and higher false-positive rates for the Rosenfeld criteria in the hip for our geographically distinct population. Using the Rosenfeld criteria, MRIs would have been ordered unnecessarily in half of our series. Because of potential differences in regional microbiology and anatomic-specific factors, general predictive criteria for coexisting PAI based a single geographic region may be less generalizable to cases of hip sepsis in other geographic areas such as the Northeastern United States. LEVEL OF EVIDENCE: Level 4-retrospective cohort study.


Assuntos
Artrite Infecciosa/complicações , Articulação do Quadril , Artropatias/diagnóstico , Adolescente , Adulto , Artrite Infecciosa/terapia , Criança , Pré-Escolar , Comorbidade , Desbridamento/métodos , Feminino , Articulação do Quadril/microbiologia , Articulação do Quadril/cirurgia , Humanos , Lactente , Imagem por Ressonância Magnética/normas , Masculino , Osteomielite/complicações , Osteonecrose/etiologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Irrigação Terapêutica , Adulto Jovem
18.
World Neurosurg ; 122: e655-e666, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30992117

RESUMO

BACKGROUND: Underestimation of the spinal cord's volume or position during spine stereotactic radiosurgery can lead to severe myelopathy, whereas overestimation can lead to tumor underdosage. Spinal cord delineation is commonly achieved by registering a magnetic resonance imaging (MRI) study with a computed tomography (CT) simulation scan or by performing myelography during CT simulation (myelosim). We compared treatment planning outcomes for these 2 techniques. METHODS: Twenty-three cases of spine stereotactic radiosurgery were analyzed that had both a myelosim and corresponding MRI study for registration. The spinal cord was contoured on both imaging data sets by 2 independent blinded physicians, and Dice similarity coefficients were calculated to compare their spatial overlap. Two treatment plans (16 Gy and 18 Gy) were created using the MRI and CT contours (92 plans total). Dosimetric parameters were extracted and compared by modality to assess tumor coverage and spinal cord dose. RESULTS: No differences were found in the partial spinal cord volumes contoured on MRI versus myelosim (4.71 ± 1.09 vs. 4.55 ± 1.03 cm3; P = 0.34) despite imperfect spatial agreement (mean Dice similarity coefficient, 0.68 ± 0.05). When the registered MRI contours were used for treatment planning, significantly worse tumor coverage and greater spinal cord doses were found compared with myelosim planning. For the 18-Gy plans, 10 of 23 MRI cases (43%) exceeded the spinal cord or cauda dose constraints when using myelosim as the reference standard. CONCLUSIONS: Significant spatial, rather than volumetric, differences were found between the MRI- and myelosim-defined spinal cord structures. Tumor coverage was compromised with MRI-based planning, and the high spinal cord doses were a concern. Future work is necessary to compare thin-cut, volumetric MRI registration or MRI simulation with myelosim.


Assuntos
Imagem por Ressonância Magnética/normas , Radiocirurgia/normas , Medula Espinal/diagnóstico por imagem , Medula Espinal/cirurgia , Tomografia Computadorizada por Raios X/normas , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imagem por Ressonância Magnética/métodos , Masculino , Radiocirurgia/métodos , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X/métodos
19.
Early Hum Dev ; 132: 52-57, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30986647

RESUMO

BACKGROUND: Neurological development is determined by brain growth. Methods to measure total brain volume (TBV) in clinical settings are limited. MR-imaging represents the gold-standard. AIMS: The present study tests the hypotheses that in infants without any brain pathology, TBV - as determined by MRI - can be accurately estimated by cranial volume (CrV), measured by 3D-laser scanning. In case of good correlation of CrV with TBV it was further tested, whether CrV can be also estimated by (I) head circumference (HC) or (II) by other technology than laser scanning. STUDY DESIGN & SUBJECTS: To test the hypothesis, that TBV can be reliably estimated by CrV-measurement, data from routine MRI and 3D-laser-scanner measurements were analyzed in infants if no major structural brain anomaly was found in MR-imaging. To test whether CrV can be predicted by HC-measurements during infancy, data from routine follow-up visits were used from preterms born in a two year period. Preterms are invited for a routine follow-up visit (which includes laser scanning of the head) at an age of 3 months and, for further follow-ups at 6, 9 or 12 months. To compare accuracy of CrV measurement by other techniques, a puppet head was measured, using different 3D-measurement principles: (i) Structured light projection system, (ii) The non-invasive laser-shape-digitizer, and (iii) Structure-from-motion (SFM) technique. OUTCOME MEASURES: TBV was compared with CrV using a Passing-Bablok-Regression. To determine how well HC predicts CrV, the coefficient of determinant (R2) was calculated for each age group. RESULTS: CrV and TBV of 25 infants (median age 19 month, body weight of 11 kg) showed a median bias of -86.7 mm3 with a slightly smaller TBV (median of 1034.1 mm3, IQR 875.9 … 1179.8 mm3) than CrV (median 1092.2, IQR 950.5 … 1258.4 mm3). CrV was poorly estimated by HC, with R2 between 0.79 and 0.87 at 3 and 9 month of age respectively. For the non-invasive laser-shape-digitizer and the SFM-technique the accuracy was good (radial coordinate differences ±0.3 vs. ±0.5 mm). CONCLUSION: The present study provides convincing evidence that CrV can be used to estimate TBV in routine care, whereas HC is a poor predictor of individual CrV.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem Tridimensional/métodos , Encéfalo/anatomia & histologia , Humanos , Imagem Tridimensional/instrumentação , Imagem Tridimensional/normas , Lactente , Lasers , Imagem por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/normas , Tamanho do Órgão , Crânio/diagnóstico por imagem
20.
Clin Imaging ; 55: 181-187, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30965182

RESUMO

RATIONALE AND OBJECTIVES: Interpreting functional magnetic resonance imaging (fMRI) can be an overwhelming and challenging task for trainees, particularly when post processing, synthesizing and interpreting data from multiple language paradigms. Currently, there is no established best method for teaching fMRI interpretation to new trainees. The purpose of our study is to compare the use of combined task activation display (CTAD) and conventional display of fMRI language paradigms as an effective method to teach fMRI to the introductory learner. MATERIALS AND METHODS: Following IRB approval, 43 unique cases (with 10 repeat cases to assess intra-reader variability) were identified based on the inclusion/exclusion criteria. Eight radiology trainees, without prior exposure to fMRI, were asked to determine language lateralization based on activation of Wernicke's area, Broca's area, and the pre-supplementary motor area. Prior to trainee interpretation, a 15-minute training session was conducted to describe the expected anatomic locations of the language centers. Trainees were asked to determine language dominance using either the CTAD or conventional methods. Following a 6-week washout period, the same eight trainees were asked to interpret the cases using the opposite interpretation approach. RESULTS: Interpreting fMRI with the CTAD method significantly increased trainee accuracy (85.4% vs 70.9% p < 0.001) and trainee confidence (4.3 vs 3.6 p < 0.001), while decreasing time to interpretation (mean difference of 29 min), and intra-reader variability when compared to the conventional approach. CONCLUSION: Combined task activation display is an effective method to teach fMRI to introductory learners.


Assuntos
Educação de Pós-Graduação em Medicina/métodos , Radiologia/educação , Adulto , Mapeamento Encefálico/métodos , Mapeamento Encefálico/normas , Córtex Cerebral/fisiologia , Competência Clínica/normas , Epilepsia/diagnóstico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Linguagem , Imagem por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/normas , Masculino , Radiologistas/educação , Radiologistas/normas , Ensino
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