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1.
Cancer Imaging ; 23(1): 17, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36793094

RESUMO

BACKGROUND: Although MRI is a radiation-free imaging modality, it has historically been limited in lung imaging due to inherent technical restrictions. The aim of this study is to explore the performance of lung MRI in detecting solid and subsolid pulmonary nodules using T1 gradient-echo (GRE) (VIBE, Volumetric interpolated breath-hold examination), ultrashort time echo (UTE) and T2 Fast Spin Echo (HASTE, Half fourier Single-shot Turbo spin-Echo). METHODS: Patients underwent a lung MRI in a 3 T scanner as part of a prospective research project. A baseline Chest CT was obtained as part of their standard of care. Nodules were identified and measured on the baseline CT and categorized according to their density (solid and subsolid) and size (> 4 mm/ ≤ 4 mm). Nodules seen on the baseline CT were classified as present or absent on the different MRI sequences by two thoracic radiologists independently. Interobserver agreement was determined using the simple Kappa coefficient. Paired differences were compared using nonparametric Mann-Whitney U tests. The McNemar test was used to evaluate paired differences in nodule detection between MRI sequences. RESULTS: Thirty-six patients were prospectively enrolled. One hundred forty-nine nodules (100 solid/49 subsolid) with mean size 10.8 mm (SD = 9.4) were included in the analysis. There was substantial interobserver agreement (k = 0.7, p = 0.05). Detection for all nodules, solid and subsolid nodules was respectively; UTE: 71.8%/71.0%/73.5%; VIBE: 61.6%/65%/55.1%; HASTE 72.4%/72.2%/72.7%. Detection rate was higher for nodules > 4 mm in all groups: UTE 90.2%/93.4%/85.4%, VIBE 78.4%/88.5%/63.4%, HASTE 89.4%/93.8%/83.8%. Detection of lesions ≤4 mm was low for all sequences. UTE and HASTE performed significantly better than VIBE for detection of all nodules and subsolid nodules (diff = 18.4 and 17.6%, p = < 0.01 and p = 0.03, respectively). There was no significant difference between UTE and HASTE. There were no significant differences amongst MRI sequences for solid nodules. CONCLUSIONS: Lung MRI shows adequate performance for the detection of solid and subsolid pulmonary nodules larger than 4 mm and can serve as a promising radiation-free alternative to CT.


Assuntos
Neoplasias Pulmonares , Pulmão , Humanos , Estudos Prospectivos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia
2.
Acta ortop. bras ; 31(spe3): e268124, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1505507

RESUMO

ABSTRACT Introduction: Tibial shaft fracture is the most common long-bone fracture, and the standard treatment is intramedullary (IM) nail fixation. Regardless of the development of this technique pseudoarthrosis remains prevalent. Objectives: Evaluate the correlation between wedge fragment size and displacement, displacement of the main fragments of the 42B2 type, and pseudoarthrosis incidence. Methods: We retrospectively assessed all patients with 42B2 type fracture treated with IM nailing between January, 2015 and December, 2019. Six radiographic parameters were defined for preoperative radiographs in the anteroposterior (AP) and lateral views. Another six parameters were defined for postoperative radiographs at three, six, and 12 months. The Radiographic Union Score for Tibial Fractures score was used to assess bone healing. Results: Of 355 patients with tibial shaft fractures, 51 were included in the study. There were 41 (82.0%) male patients, with a mean age of 36.7 years, 37 (72.5%) had open fractures, and 28 (54.9%) had associated injuries. After statistical analysis, the factors that correlated significantly with nonunion were wedge height > 18 mm, preoperative translational displacement of the fracture in the AP view > 18 mm, and final distance of the wedge in relation to its original anatomical position after IM nailing > 5 mm. Conclusion: Risk factors for nonunion related to the wedge and42B2 fracture are wedge height > 18 mm, initial translation in the AP view of the fracture > 18 mm, and distance > 5 mm of the wedge from its anatomical position after IM nailing. Evidence level III; Retrospective comparative study .


RESUMO Introdução: A fratura da diáfise da tíbia é a fratura mais comum dentre os ossos longos, sendo o tratamento padrão a fixação com haste intramedular (HIM). Independentemente do desenvolvimento da técnica cirúrgica, a pseudoartrose continua prevalente. Objetivo: Avaliar a associação entre o tamanho e o desvio da cunha, os desvios dos fragmentos principais do tipo 42B2 e a incidência de pseudoartrose. Métodos: Avaliamos, retrospectivamente, todos os pacientes com fraturas tipo 42B2 tratados com hastes intramedulares entre janeiro de 2015 e dezembro de 2019. Seis parâmetros radiográficos foram definidos para as radiografias pré-operatórias nas incidências anteroposterior (AP) e perfil. Outros seis parâmetros foram definidos para as radiografias pós-operatórias em 3, 6 e 12 meses de acompanhamento pós-operatório. O Escore Radiográfico de União para as Fraturas da Tíbia (RUST) foi o instrumento usado para avaliar a consolidação óssea. Resultados: Dos 355 pacientes com fraturas da diáfise da tíbia, 51 foram incluídos no estudo. Os pacientes incluídos foram 41 (82,0%) do sexo masculino, com idade média de 36,7 anos, 37 (72,5%) com fraturas expostas e 28 (54,9%) com lesões associadas. Após análise estatística, os fatores que se correlacionaram significativamente com a não consolidação foram a altura da cunha > 18 mm, o deslocamento translacional pré-operatório da fratura na incidência AP > 18 mm e a distância final da cunha em relação à sua posição anatômica original após a cravação do MI > 5 mm. Conclusão: Os fatores de risco para a pseudartrose relacionada com a fratura em cunha e42B2 são a altura da cunha > 18 mm, a translação inicial na vista AP da fratura > 18 mm e a distância > 5 mm da cunha em relação à sua posição anatómica após a fixação IM. Nível de evidência III; estudo comparativo retrospectivo. Nível de evidência III; Estudo retrospectivo comparativo .

3.
Eur J Radiol Open ; 9: 100442, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36193450

RESUMO

Purpose: The quantitative assessment of impaired lung motions and their association with the clinical characteristics of COPD patients is challenging. The aim of this study was to measure respiratory kinetics, including asynchronous movements, and to analyze the relationship between lung area and other clinical parameters. Materials and methods: This study enrolled 10 normal control participants and 21 COPD patients who underwent dynamic MRI and pulmonary function testing (PFT). The imaging program was implemented using MATLAB®. Each lung area was detected semi-automatically on a coronal image (imaging level at the aortic valve) from the inspiratory phase to the expiratory phase. The Dice index of the manual measurements was calculated, with the relationship between lung area ratio and other clinical parameters, including PFTs then evaluated. The asynchronous movements of the diaphragm were also evaluated using a sagittal image. Results: The Dice index for the lung region using the manual and semi-automatic extraction methods was high (Dice index = 0.97 ± 0.03). A significant correlation was observed between the time corrected lung area ratio and percentage of forced expiratory volume in 1 s (FEV1%pred) and residual volume percentage (RV%pred) (r = -0.54, p = 0.01, r = 0.50, p = 0.03, respectively). The correlation coefficient between each point of the diaphragm in the group with visible see-saw like movements was significantly lower than that in the group without see-saw like movements (value = -0.36 vs 0.95, p = 0.001). Conclusion: Semi-automated extraction of lung area from Cine MRI might be useful for detecting impaired respiratory kinetics in patients with COPD.

4.
Preprint em Português | SciELO Preprints | ID: pps-4462

RESUMO

Objective: to retrospectively evaluate and compare the proportions of complications and radiographic findings of two- and three-part proximal humerus fracture osteosynthesis with two treatment methods: third-generation locked intramedullary nail and locked plate. Methods: 46 patients with a mean age of 58.9±16.6 years were evaluated between January 2020 and January 2021. In sixteen cases (34.8%), an intramedullary nail was used, and in thirty cases (65 .2%), the proximal humerus locked plate. The evaluation used included the rate of complications with a minimum follow-up of 6 months postoperatively and radiographic evaluation. Results: there was no significant difference between the groups regarding the proportion of complications (nail group 18.8%, plate group 13.3%; p=0.681). The nail group showed less residual loss in varus (cervicodiaphyseal angle, nail group 132.1º±2.3º, plate group 123.8º±10.1º; p<0.001). In the plaque group, women had a lower value (1.43±0.22) of the tuberosity-deltoid index (DTI) compared to men (1.58±0.11) (p=0.022). Conclusions: in the short-term follow-up, osteosynthesis, with locked plate and intramedullary nail, did not show differences in the proportions of complications. The nail group showed less change in the post-operative cervicodiaphyseal angle, however, there were two serious complications with cut out and varus deviation requiring a new surgical approach in the nail group.


Objetivo: avaliar intra, de modo retrospectivo, e comparando as complicações e os achados radiográficos da osteossíntese da úmero proximal em duas e três partes com dois métodos de tratamento: a terceira geração e placa bloqueada do tratamento. Métodos: foram obtidos 46 pacientes com média de idade de 58,9±16,6 anos entre janeiro de 2020 a janeiro de 2021. ,2%), uma placa bloqueada de úmero proximal. A utilização de uma taxa de acompanhamento com acompanhamento de acompanhamento pós-operatório e avaliação radiográfica. Resultados: não houve diferença significativa entre os grupos quanto à proporção de complicações (grupo pressa, 8%, grupo placa 13,61; p=0,61). O grupo pressa apresentou menor perda residual em varo (ângulo cervicodiafisário grupo pressa 132,1º±2,3º, grupo placa 123,8º±10,1º; p<0,001). No grupo placa, as mulheres apresentaram menor valor (1,43±0,22) do índice tuberosidade-deltoide (DTI) em relação aos homens (1,58±0,11) (p=0,022). Conclusões: sem seguimento de curto prazo, a osteoconformidade com placas fixadas e pressa intramedular, não apresentou diferenças nas proporções de complicações. O grupo apresentou menor alteração do projeto cervicodiafisário pós-operatório, entretanto, duas complicações graves com cut out e desvio em varo com necessidade de reabordagem integrada no grupo pressa. 22) do índice tuberosidade-deltoide (DTI) em relação aos homens (1,58±0,11) (p=0,022). Conclusões: sem seguimento de curto prazo, a osteoconformidade com placas fixadas e pressa intramedular, não apresentou diferenças nas proporções de complicações. O grupo apresentou menor alteração do projeto cervicodiafisário pós-operatório, entretanto, duas complicações graves com cut out e desvio em varo com necessidade de reabordagem integrada no grupo pressa. 22) do índice tuberosidade-deltoide (DTI) em relação aos homens (1,58±0,11) (p=0,022). Conclusões: sem seguimento de curto prazo, a osteoconformidade com placas fixadas e pressa intramedular, não apresentou diferenças nas proporções de complicações. O grupo apresentou menor alteração do projeto cervicodiafisário pós-operatório, entretanto, duas complicações graves com cut out e desvio em varo com necessidade de reabordagem integrada no grupo pressa. 

5.
Magn Reson Imaging ; 85: 35-37, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34662697

RESUMO

Pericardial diverticulum is a focal herniation of the pericardium. It is differentiated from a pericardial cyst by the presence of communication with the pericardial cavity. Radiological differentiation between the diverticulum and cyst via computed tomography is difficult unless changes in size are identified with different body positions in additional scans. Herein we describe a case of pericardial diverticulum that was successfully diagnosed via the detection of internal pericardial flow in black blood-prepared T2 half-Fourier acquisition single-shot turbo spin-echo magnetic resonance imaging. Detection of a flow void in the pericardial sac may be a definitive magnetic resonance imaging finding in the diagnosis of pericardial diverticulum.


Assuntos
Cistos , Divertículo , Divertículo/diagnóstico por imagem , Análise de Fourier , Humanos , Imageamento por Ressonância Magnética/métodos , Pericárdio/diagnóstico por imagem
6.
Magn Reson Med ; 87(4): 1914-1922, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34888942

RESUMO

PURPOSE: Fetal brain Magnetic Resonance Imaging suffers from unpredictable and unconstrained fetal motion that causes severe image artifacts even with half-Fourier single-shot fast spin echo (HASTE) readouts. This work presents the implementation of a closed-loop pipeline that automatically detects and reacquires HASTE images that were degraded by fetal motion without any human interaction. METHODS: A convolutional neural network that performs automatic image quality assessment (IQA) was run on an external GPU-equipped computer that was connected to the internal network of the MRI scanner. The modified HASTE pulse sequence sent each image to the external computer, where the IQA convolutional neural network evaluated it, and then the IQA score was sent back to the sequence. At the end of the HASTE stack, the IQA scores from all the slices were sorted, and only slices with the lowest scores (corresponding to the slices with worst image quality) were reacquired. RESULTS: The closed-loop HASTE acquisition framework was tested on 10 pregnant mothers, for a total of 73 acquisitions of our modified HASTE sequence. The IQA convolutional neural network, which was successfully employed by our modified sequence in real time, achieved an accuracy of 85.2% and area under the receiver operator characteristic of 0.899. CONCLUSION: The proposed acquisition/reconstruction pipeline was shown to successfully identify and automatically reacquire only the motion degraded fetal brain HASTE slices in the prescribed stack. This minimizes the overall time spent on HASTE acquisitions by avoiding the need to repeat the entire stack if only few slices in the stack are motion-degraded.


Assuntos
Feto , Imageamento por Ressonância Magnética , Feminino , Feto/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Gravidez
7.
Eur J Radiol Open ; 8: 100390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926727

RESUMO

BACKGROUND: To estimate the diagnostic value of dynamic magnetic resonance imaging (MRI) for the assessment of the temporomandibular joint (TMJ) compared to standard static MRI sequences in patients with TMJ dysfunction (TMD). METHODS AND MATERIALS: This retrospective study included 71 patients with clinical diagnose of TMD. We acquired 5 static T1- and T2-weighted sequences in parasagittal and paracoronal views and one dynamic sequence (trueFISP) in parasagittal view for each TMJ. Image analysis included evaluation of morphology and function of intra-articular structures and rating of the dynamic images as more, equally, or less informative compared to static MRI sequences. RESULTS: Mean age was 35.0 ± 14.7 years and 50/71 (70.4%) were female. 127/142 (89.4%) TMJs were of diagnostic quality. 42/127 (33.1%) TMJs showed no disc displacement (DD), 56 (44.1%) had DD with disc reduction (DDwR), and 29 (22.8%) had DD without disc reduction (DDwoR). In 38/127 (29.9%) TMJs, dynamic images were rated "more informative", in 84/127 (66.2%) "equally informative", and in 5/127 (3.9%) "less informative" compared to solely static images. Overall, 27/71 (38.0%) patients benefited from additional dynamic sequences compared to solely static images. Dynamic images were "more informative" in TMJs with DDwR (23/56 [41.1%], p < 0.001) and in TMJs with DDwoR (13/29 [44.8%], p = 0.007), while it had no beneficial value for TMJ without DD. For evaluation of joint effusion, static T2-weighted images were rated better in 102/127 (80.3%) TMJs compared to dynamic images (<0.001). CONCLUSION: Dynamic MRI sequences are beneficial for the evaluation of morphology and function of the TMJ compared to static sequences, especially in patients with temporomandibular disc displacement.

8.
Magn Reson Med ; 86(3): 1463-1471, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33929055

RESUMO

PURPOSE: To develop a true single shot turbo spin echo (SShTSE) acquisition with Dixon for robust T2 -weighted abdominal imaging with uniform fat and water separation at 3T. METHODS: The in-phase (IP) and out-of-phase (OP) echoes for Dixon processing were acquired in the same repetition time of a SShTSE using partial echoes. A phase-preserved bi-directional homodyne reconstruction was developed to compensate the partial echo and the partial phase encoding of SShTSE. With IRB approval, the SShTSE-Dixon was compared against standard SShTSE, without and with fat suppression using spectral adiabatic inversion recovery (SPAIR) in 5 healthy volunteers and 5 patients. The SNR and contrast ratio (CR) of spleen to liver were compared among different acquisitions. RESULTS: The bi-directional homodyne reconstruction successfully minimized ringing artifacts because of partial acquisitions. SShTSE-Dixon achieved uniform fat suppression compared to SShTSE-SPAIR with fat suppression failures of 1/10 versus 10/10 in the axial plane and 0/5 versus 5/5 in the coronal plane, respectively. The SNRs of the liver (12.2 ± 4.9 vs. 11.7 ± 5.2; P = .76) and spleen (25.9 ± 11.6 vs. 23.7 ± 9.7; P = .14) were equivalent between fat-suppressed images (SShTSE-Dixon water-only and SShTSE-SPAIR). The SNRs of liver (14.4 ± 5.7 vs. 13.4 ± 5.0; P = .60) and spleen (26.5 ± 10.1 vs. 25.7 ± 8.5; P = .56) were equivalent between non-fat-suppressed images (SShTSE-Dixon IP and SShTSE). The CRs of spleen to liver were also similar between fat-suppressed images (2.6 ± 0.4 vs. 2.5 ± 0.5; P =.92) and non-fat-suppressed images (2.3 ± 0.6 vs. 2.2 ± 0.4; P =.84). CONCLUSION: SShTSE-Dixon generates robust abdominal T2 -weighted images at 3T with and without uniform fat suppression, along with perfectly co-registered fat-only images in a single acquisition.


Assuntos
Imageamento por Ressonância Magnética , Água , Tecido Adiposo/diagnóstico por imagem , Humanos , Aumento da Imagem , Interpretação de Imagem Assistida por Computador
9.
Acta ortop. bras ; 29(2): 76-80, Mar.-Apr. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1248599

RESUMO

ABSTRACT Introduction: Ideal Nail Length (INL) provides better outcomes after Intramedullary Nailing (IMN) of Tibia Shaft Fractures (TSF). Intraoperative methods do not allow for preoperative planning. Changing the nail may cause complications. X-rays are commonly used, but displacement or magnification errors may occur. Forearm measurements may be benefical in bilateral TSF. We aim to examine correlations of anthropometric measurements (AMs) and INL and use them to obtain formulae. Materials and methods: Tuberositas Tibia-Medial Malleolus (TM), Tuberositas Tibia-Ankle joint (TA), knee-ankle joint (JJ), and olecranon tip-5th Metacarpal head (OM) distances were evaluated in 76 IMN patients. Correlation analyses were performed and the results used to create formulae. Results: The correlations between INL and TM-left, TM-right, TA-left, TA-right, OM-left, OM-right, JJ-left, JJ-right were 0.81, 0.83, 0.77, 0.77, 0.82, 0.80, 0.90, 0.91 respectively for males; and 0.93, 0.89, 0.88, 0.86, 0.80, 0.82, 0.90, 0.89 respectively for females. AMs show excellent correlation in both sexes (p<0.0001). Regression analysis was statistically significant in all formulae. The most compatible correlations in males were JJ-right and JJ-left; and in females, TM-left, TM-right, and JJ-right. Conclusion: The most compatible correlations wth INL were JJ in males, and TM and JJ in females. OM can be used in the presence of bilateral TSF, edema, wounds and obesity. AMs are useful preoperatively. The formulae can be used to ensure INL and reduce errors, time and radiation. Level of Evidence: Level I, Testing of previously developed diagnostic criteria on consecutive patients (with the universally applied reference gold standard).


RESUMO Introdução: O comprimento ideal da haste (CIH) proporciona desfechos melhores depois da colocação de haste intramedular (HIM) em fraturas da diáfise da tíbia (FDT). Os métodos dessa cirurgia não permitem o planejamento pré-operatório. A troca da haste pode causar complicações. Em geral, são usadas radiografias, mas podem ocorrer erros de deslocamento ou de tamanho. As medições do antebraço podem ser benéficas nas FDTs bilaterais. Nosso objetivo é examinar as correlações das medidas antropométricas (MAs) e CIH e usá-las para obter fórmulas. Materiais e métodos: As distâncias entre Tuberosidade da tíbia-Maléolo medial (TM), Tuberosidade da tíbia-Articulação do tornozelo (TT), Articulações do joelho e do tornozelo (JT) e extremidade do olécrano-cabeça do 5o metacarpal (OM) foram avaliadas em 76 pacientes com HIM. Foram realizadas análises de correlação e os resultados foram usados para criar fórmulas. Resultados: As correlações entre CIH e TM-esquerda, TM-direita, TT-esquerda, TT-direita, OM-esquerda, OM-direita, JT-esquerda, JT-direito foram 0,81, 0,83, 0,77, 0,77, 0,82, 0,80, 0,90, 0,91 para homens e 0,93, 0,89, 0,88, 0,86, 0,80, 0,82, 0,90, 0,89 para mulheres. As MAs tiveram excelente correlação em ambos os sexos (p < 0,0001). A análise de regressão foi estatisticamente significativa em todas as fórmulas. As correlações mais compatíveis em homens foram JT-direita e JT-esquerda; nas mulheres, foram TM-esquerda, TM-direita, e JT-direita. Conclusão: As correlações mais compatíveis com CIH foram JT em homens e TM e JT em mulheres. A OM pode ser usada em FDT bilateral, edema, feridas e obesidade. As MAs são úteis no pré-operatório. As fórmulas podem ser usadas para garantir o CIH e reduzir erros, tempo e radiação. Nível de evidência: Nível I, Desenvolvimento de critérios diagnósticos em pacientes consecutivos (com padrão de referência "ouro" aplicado).

10.
Gigascience ; 10(3)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33739401

RESUMO

BACKGROUND: Large streamed datasets, characteristic of life science applications, are often resource-intensive to process, transport and store. We propose a pipeline model, a design pattern for scientific pipelines, where an incoming stream of scientific data is organized into a tiered or ordered "data hierarchy". We introduce the HASTE Toolkit, a proof-of-concept cloud-native software toolkit based on this pipeline model, to partition and prioritize data streams to optimize use of limited computing resources. FINDINGS: In our pipeline model, an "interestingness function" assigns an interestingness score to data objects in the stream, inducing a data hierarchy. From this score, a "policy" guides decisions on how to prioritize computational resource use for a given object. The HASTE Toolkit is a collection of tools to adopt this approach. We evaluate with 2 microscopy imaging case studies. The first is a high content screening experiment, where images are analyzed in an on-premise container cloud to prioritize storage and subsequent computation. The second considers edge processing of images for upload into the public cloud for real-time control of a transmission electron microscope. CONCLUSIONS: Through our evaluation, we created smart data pipelines capable of effective use of storage, compute, and network resources, enabling more efficient data-intensive experiments. We note a beneficial separation between scientific concerns of data priority, and the implementation of this behaviour for different resources in different deployment contexts. The toolkit allows intelligent prioritization to be `bolted on' to new and existing systems - and is intended for use with a range of technologies in different deployment scenarios.


Assuntos
Disciplinas das Ciências Biológicas , Software , Diagnóstico por Imagem
11.
Eur J Radiol Open ; 7: 100278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163586

RESUMO

PURPOSE: It is important to identify features on computed tomography (CT) that can distinguish between benign and premalignant or malignant pancreatic cysts to avoid unnecessary surgeries. This study investigated the preoperative diagnostic evaluation of cystic pancreatic lesions to determine how advanced imaging and clinical factors should guide management. METHODS: In total, 53 patients with 27 benign and 26 premalignant or malignant cysts were enrolled. CT features of the cysts were compared using univariate and multivariate analyses. RESULTS: On univariate analysis, a solid component (p < 0.01), septation (p < 0.01), location (p < 0.01), border (p < 0.01), wall enhancement (p = 0.01), lesion margins (p < 0.01), pancreatic atrophy (p = 0.04), and a cystic wall (p < 0.01) were all significantly different between benign and premalignant or malignant cysts. On multivariate analysis, only a solid component (p < 0.01) and septation (p < 0.01) were significant. CONCLUSION: A thin cystic wall, uniform homogeneity, a clear border, the presence of septation, pancreatic atrophy, and the absence of both wall enhancements and solid components were more frequently seen in benign cysts. A thick wall, lack of homogeneity, the presence of wall enhancements and solid components, absence of septation, only a small degree of pancreatic atrophy, and unclear borders were more frequent among premalignant or malignant cysts. The only CT features to differentiate benign from premalignant or malignant cysts were a solid component and septation.

12.
World Neurosurg ; 144: e648-e659, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32961357

RESUMO

BACKGROUND: The use of nonsedated T2-weighted Half-Fourier Acquisition Single-shot Turbo spin Echo magnetic resonance imaging (MRI) sequences in screening for spinal cord syrinx in neonates with spinal dysraphism has not been reported in the literature. We sought to review our experience using T2-weighted Half-Fourier Acquisition Single-shot Turbo spin Echo imaging of the spine (i.e., rapid spine MRI) in nonsedated neonates for detecting spinal cord syrinx in neonates with spinal dysraphism. METHODS: We performed a retrospective search of our radiology database for neonates with spinal dysraphism who had rapid spine MRI between May 2017 and February 2020. The images were reviewed in conjunction with clinical findings and standard spine imaging, when available. RESULTS: Thirty studies (in 29 neonates) fulfilled our inclusion criteria. Of the 26 neonates with myelomeningocele, 5 of them (19%) had spinal cord syrinx identified on neonatal rapid spine MRI. An additional 2 patients developed syrinx by 2 years of age. Potential pitfalls identified in interpreting rapid spine MRI include motion artifacts and distinguishing a severe holocord syrinx from a truncated spinal cord. CONCLUSIONS: Rapid spine MRI acquired without sedation or anesthesia may be used as a screening technique to detect spinal cord syrinx in neonates with spinal dysraphism.


Assuntos
Imageamento por Ressonância Magnética/métodos , Disrafismo Espinal/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Siringomielia/diagnóstico por imagem , Diagnóstico Precoce , Feminino , Humanos , Recém-Nascido , Masculino , Meningomielocele/complicações , Estudos Retrospectivos , Disrafismo Espinal/complicações
13.
Cancer Imaging ; 20(1): 39, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546207

RESUMO

PURPOSE: Evaluate the feasibility of fluorine-18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) and magnetic resonance (MR) imaging in patients with gastric cancer by optimizing the scan protocol and to compare the image quality to 18F FDG PET and computed tomography (CT). METHODS: The PET/CT and PET/MR imaging were sequentially performed in 30 patients with gastric cancer diagnosed by gastroscope using a single-injection-with-dual-imaging protocol. After intravenous injection of 18F-FDG (mean, 249 MBq), PET/CT imaging including low-dose CT was performed (mean uptake time, 47 ± 6 min), and PET/MR imaging including a T1-weighted Dixon sequence for attenuation correction and two different T2-weighted sequences was subsequently acquired (88 ± 15 min after 18F-FDG injection). Four series of images (CT from PET/CT, T1W, T2W Half-Fourier acquisition single-shot turbo spin-echo [T2W-HASTE] and T2W-BLADE from PET/MR) were visually evaluated using a 3-4 points scale for: (1) image artifacts, (2) lesion conspicuity and (3) image fusion quality. The characteristics of the primary lesions were assessed and compared between the PET/CT and PET/MR acquisitions. RESULTS: The image quality and lesion conspicuity of the T2W-HASTE images were significantly improved compared to that of the T2W-BLADE images. A significantly higher number of artifacts were seen in the T2W-HASTE images compared with the T1W and CT images (p < 0. 05). No differences in the accuracy of image fusion between PET/MR and PET/CT (p > 0. 05); however, significant difference was seen in the lesion conspicuity measurements (p < 0.05) with T2W-HASTE being superior. For information about the primary lesion characteristics, the T2W-HASTE images provided the most successful identifications compared with those of the T1W and PET/CT (13vs7vs5) images. CONCLUSIONS: PET/MR with the T2W-HASTE was better at revealing the details of local stomach lesions compared with PET/CT imaging. Combining the PET/MR with the T2W-HASTE technique is a promising imaging method for diagnosing and staging gastric cancer.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/normas , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/normas
14.
Phys Med ; 73: 179-189, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32371141

RESUMO

PURPOSE: The aim of this study is to introduce a novel DWI-MRI phantom and to compare Apparent Diffusion Coefficient (ADC) measurements, utilizing EPI-DWI and HASTE-DWI sequences and two different fitting algorithms. MATERIALS AND METHODS: 23 test tubes with different sucrose concentrations and polyacrylamide gels were used as a phantom for ADC measurements. The phantom was scanned on a clinical MRI system (1.5 T) over a two-month period utilizing an EPI-DWI and a HASTE-DWI sequence. ADC maps were calculated using a Weighted Linear (WL) and a Non Linear (NL) fitting algorithm. Measurements were performed with two sequences and two fitting algorithms. Geometric Distortions (GD), Ghosting Ratios (GR) and Signal to Structured Noise Ratios (SSNRs) were estimated using both sequences from the resultant ADC parametric maps. RESULTS: Polyacrylamide gels reveal lower coefficient of variation (CV%) as compared to sucrose solutions. ADC measurements performed with WL and NL algorithms reveal identical results with both sequences. WL and NL algorithms require approx. 3 s and 7 min respectively, for a single slice. EPI-DWI reveals a mean percent ADC value difference of (+4.5%) as compared to HASTE-DWI, regardless the type of fitting algorithm. CONCLUSION: Polyacrylamide gels can serve as a better means for simulating ADC values, compared with sucrose solutions used in this study. WL can be proposed as the method for ADC measurements in daily clinical practice. WL is significantly faster than NL fitting method and equally precise. SSNR measured directly on ADC maps is an excellent means for testing the precision of ADC measurements.


Assuntos
Imagem de Difusão por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Modelos Lineares
15.
Clin Imaging ; 60(2): 244-248, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31968283

RESUMO

PURPOSE: To compare half-Fourier acquisition single-shot turbo spin-echo thoracic MRI (HASTE-MRI) with chest x-ray (CXR). METHODS: A total of 287 patients (median age 53 years) undergoing both axial HASTE-MRI and CXR (<7 days apart) were retrospectively analyzed. Pulmonary nodules and consolidations, pleural effusion, and cardiac or aortic enlargement were considered. Detection rate (DR) and intra- and inter-technique agreement for both HASTE-MRI and CXR, were assessed. RESULTS: Pulmonary nodule DR was 1.7% (5/287) at both techniques (perfect inter-technique agreement); inter-reader agreement was perfect for HASTE-MRI (κ = 1.000) and modest for CXR (κ = 0.393). Pleural effusion DR at HASTE-MRI (19.1%, 55/287) was higher (p < 0.001) than at CXR (13.9%, 40/287), but their agreement was almost perfect (κ = 0.812); inter-reader agreement was almost perfect for HASTE-MRI (κ = 0.902) and substantial for CXR (κ = 0.773). Pulmonary consolidation DR at HASTE-MRI (8.4%, 24/287) was similar (p = 0.625) to that at CXR (7.7%, 22/287), with an almost perfect inter-technique agreement (κ = 0.905); inter-reader agreement was moderate for both HASTE-MRI (κ = 0.639) and CXR (κ = 0.554). Cardiac enlargement DR at HASTE-MRI (45.3%, 130/287) was borderline significantly lower (p = 0.057) than that at CXR (48.1%, 138/287), with an almost perfect inter-technique agreement (κ = 0.902); inter-reader agreement was substantial for both HASTE-MRI (κ = 0.798) and CXR (κ = 0.744). Aortic dilation DR at HASTE-MRI (17.7%, 51/287) was significantly higher (p < 0.001) than that at CXR (9.7%, 28/287), with a substantial inter-technique agreement (κ = 0.648); inter-reader agreement was moderate for both HASTE-MRI (κ = 0.724) and CXR (κ = 0.346). CONCLUSION: HASTE-MRI and CXR showed at least a comparable DR for thoracic cardiac and non-cardiac findings.


Assuntos
Imageamento por Ressonância Magnética/métodos , Tórax/diagnóstico por imagem , Feminino , Humanos , Pneumopatias , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Raios X
16.
Ciênc. rural (Online) ; 50(6): e20190870, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1133260

RESUMO

ABSTRACT: The objective of this research was to evaluate the effect of seeder furrow opening mechanisms on soil physical characteristics, plant growth, and soybean yield in lowland areas with the presence of compacted layer near the surface. An experiment was conducted in the lowland experimental area of the Federal University of Santa Maria-RS, Brazil, during the 2015/16 and 2016/17 growing season. The experimental design was a randomized block with five replications and four treatments: Planter using shank (S) at 0.23 m depth; S at 0.13 m; Planter using double disk at 0.07 m depth and Raised-bed + S at 0.12 m depth. The use of S at 0.23 m depth allowed reduction of penetration resistance and increase of soil macroporosity in the layers 0-0.1 and 0.1-0.2 m depth in the seeding row. Sowing with S at 0.23 m depth and Raised-bed + S at 0.12 m depth allowed a better development of soybean plants in compacted irrigated rice area (higher nodulation, leaf area index and root growth), as well as higher grain yield.


RESUMO: O trabalho teve como objetivo avaliar o efeito de mecanismos sulcadores da semeadora sobre características físicas do solo, crescimento de plantas e produtividade de soja em área de terras baixas com presença de camada compactada. Para isso, foi conduzido um experimento na área de várzea da Universidade Federal de Santa Maria, durante as safras agrícolas 2015/16 e 2016/17. O delineamento experimental utilizado foi o de blocos ao acaso, com cinco repetições e quatro tratamentos, sendo eles: Haste sulcadora (HS) a 0.23 m de profundidade; HS a 0.13 m; Disco duplo a 0.07 m e Microcamalhão+HS a 0.12 m. A utilização da HS a 0.23 m possibilitou o aumento da macroporosidade e a redução da resistência à penetração mecânica do solo nas camadas de 0-0.1 e 0.1-0.2 m de profundidade na linha de semeadura. A semeadura com HS a 0.23 m e Microcamalhão+HS a 0.12 m viabilizam melhor desenvolvimento das plantas de soja em área de terras baixas compactada (maior nodulação, índice de área foliar e crescimento radicular), bem como maior produtividade de grãos.

17.
BMC Med Imaging ; 19(1): 33, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035952

RESUMO

BACKGROUND: The purpose of this study is to compare the performance of three-dimensional magnetic resonance cholangiopancreatography (3D-MRCP) with non-MRCP T2-weighted magnetic resonance imaging (MRI) sequences for diagnosis of pancreas divisum (PD). METHODS: This is a retrospective study of 342 consecutive patients with abdominal MRI including 3D-MRCP. 3D-MRCP was a coronal respiration-navigated T2-weighted sequence with 1.5 mm slice thickness. Non-MRCP T2-weighted sequences were (1) a coronal inversion recovery sequence (TIRM) with 6 mm slice thickness and (2) a transverse single shot turbo spin echo sequence (HASTE) with 4 mm slice thickness. For 3D-MRCP, TIRM, and HASTE, presence of PD and assessment of evaluability were determined in a randomized manner. A consensus read by two radiologists using 3D-MRCP, non-MRCP T2-weighted sequences, and other available imaging sequences served as reference standard for diagnosis of PD. Statistical analysis included performance analysis of 3D-MRCP, TIRM, and HASTE and testing for noninferiority of non-MRCP T2-weighted sequences compared with 3D-MRCP. RESULTS: Thirty-three of 342 patients (9.7%) were diagnosed with PD using the reference standard. Sensitivity/specificity of 3D-MRCP for detecting PD were 81.2%/69.7% (p < 0.001). Sensitivity/specificity of TIRM and HASTE were 92.5%/93.9 and 98.1%/97.0%, respectively (p < 0.001 each). Grouped sensitivity/specificity of non-MRCP T2-weighted sequences were 99.8%/91.0%. Non-MRCP T2-weighted sequences were non-inferior to 3D-MRCP alone for diagnosis of PD. 20.2, 7.3%, and 2.3% of 3D-MRCP, TIRM, and HASTE, respectively, were not evaluable due to motion artifacts or insufficient duct depiction. CONCLUSIONS: Non-MRCP T2-weighted MRI sequences offer high performance for diagnosis of PD and are noninferior to 3D-MRCP alone. TRIAL REGISTRATION: Not applicable.


Assuntos
Colangiopancreatografia por Ressonância Magnética/métodos , Pâncreas/anormalidades , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Estudos Retrospectivos , Sensibilidade e Especificidade
18.
ACM arq. catarin. med ; 48(1): 60-70, jan.-mar. 2019.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1023384

RESUMO

Objetivo: Avaliar e comparar os resultados clínicos e radiológicos de pacientes com fratura de tíbia distal, sem acometimento articular, tratados com haste intramedular ou placa e parafusos. Métodos: Foram analisados 27 pacientes, sendo 15 tratados com placa e 12 com haste intramedular, após 6 meses completos de pós operatório. Foram aplicados os escores de EVA e de Olerud-Molander, além de análise radiográfica. A análise estatística foi realizada utilizando os testes de qui quadrado e o teste de Mann-Whitney. Resultados: A média de idade foi de 45 anos e o sexo masculino foi prevalente. Foi observada alta prevalência da fratura de fíbula associada (92,6%) sendo 25,9% fixadas. A media angular de desvio foi de 2,60o nos pacientes tratados com placa e 2,42o nos tratados com haste intramedular (p=0,829). A média do escore da EVA e Escore de Olerud-Molander não mostrou diferença estatisticamente significativa entre os dois grupos. Três pacientes apresentaram pseudoartrose, sendo dois deles tratados com haste. Conclusão: Não houve consenso da superioridade de um método em relação ao outro em nossa análise. A fixação da fibula pode ser um fator determinante no alinhamento das fraturas. Cada um dos métodos apresenta vantagens e desvantagens, porém ambos mostraram resultados bons e semelhantes. A escolha do tratamento deve ser atribuida ao perfil do trauma, a condições clinicas do paciente e a experiencia do profissional.


Objective: To evaluate and compare clinical and radiological outcomes of patients with distal tibial fractures, without joint involvement, treated with intramedularry nail or plate and screws. Methods: twenty seven patiens were analyzed, 15 treated with plates and 12 treated with intramedullary nail, after 6 complete months of postoperative period. The Olerud-Molander Ankle Score and the Visual Analogue Scale for Pain, as well as radiographic analysis. Statistical analysis was performed using the chi-squared and Mann-Whitney tests. Results: The mean age was 45 years and males were more prevalent. A high prevalence of associated fíbula fracture was observed (92,6%), with 25,9% being fixed. The mean angular deviation was 2,6 degreees in patients treated with plate and 2,42 degrees in those treated with nails. (p=0,829). The Olerud-Molander Ankle Scores and the EVA did not show statistically siginifcance difference between the two groups. Three patients evolved with nonunion, two of them being treated with intramedullary nail. Conclusions: There was no consensus of the superiority of one method over the other. Fíbula fixation can be a determining factor int the fracture alingnment. Both methods has advantages and disadvantages, but both shows good and similar results. Treatment's choice shoud be attributed to trauma profile, patient's clinical conditions and surgeon's experience.

19.
Pesqui. vet. bras ; 38(10): 1909-1912, out. 2018. ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-976373

RESUMO

Technological and tissue engineering have enabled available, biologically inert, and low cost materials to be considered as viable alternatives in the surgical treatment of long bone fractures in birds. The aim of this study was to microscopically analyse osteotomized humerus of birds following the insertion of solid laser-sintered polyamide 12 rods in order to detect foreign body reaction and, thus, verify the bioinert property of the material in the bone fracture environment. Polyamide 12 intramedullary rods were inserted into the osteotomized humerus of 10 birds (white Plymouth Rock) and blocked using 2mm diameter cortical screws of varying lengths. The birds were operated at 60 days of age and monitored post-operatively for three months. Animals were euthanized at 150 days old and samples of the operated humerus collected for immunohistochemistry, light and scanning electron microscopy analysis. Results show bone consolidation without rejection of the implant and absence of inflammatory cells. Vascular Endothelial Growth Factor (VEGF) was expressed in the endothelial cells of the blood vessels at the site of the newly formed bone surrounding the implant, indicative of local angiogenesis. There was no bone growth on the surface of the rod; however, the implant did not interfere with the circumjacent bone repair. Thus, the findings of this study corroborate with the literature in characterizing polyamide as a bioinert material and, under the studied conditions, it can be concluded that polyamide 12 intramedullary rod is biocompatible and provides adequate bone consolidation in humeral fractures with no signs of rejection.(AU)


Com o desenvolvimento tecnológico e crescimento da engenharia de tecidos, o uso de materiais disponíveis, bioinertes e debaixo custo pode ser alternativa viável para o tratamento cirúrgico de fraturas em ossos longos nas aves. O objetivo do estudo foi realizar avaliação microscópica óssea após a implantação de haste maciça de poliamida, implantada em úmeros osteotomizados de galinhas para detectar reação do tipo corpo estranho, verificando a propriedade "bioinerte" do material no ambiente de fratura óssea. Foram utilizados 10 galos (Plymouth rock branca) e implantou-se a haste perfazendo o bloqueio das mesmas com parafusos corticais de 2 mm de diâmetro com comprimentos de acordo com a necessidade. As aves foram operadas aos 60 dias de vida e o acompanhamento pós-operatório ocorreu por três meses. Após a eutanásia, foram realizadas coletas do úmero operado (local de consolidação óssea) paraexame histopatológico, imuno-histoquímico e de microscopia eletrônica de varredura. Os resultados demonstraram consolidação óssea, sem presença de rejeição do material, com ausência de células inflamatórias. A neoformação óssea ao redor do implante expressou VEGF (fator de crescimento endotelial vascular) nas células endoteliais dos vasos sanguíneos caracterizando angiogênese no local. Na região de interface de tecido ósseo com a poliamida não foram observadas micro fraturas. Não houve crescimento ósseo na superfície da haste, porém a mesma não atrapalhou o reparo ósseo circunjacente. Assim, esse estudo corrobora com a literatura caracterizando a poliamida como um material bioinerte, e nas condições estudadas pode-se concluir que o uso da haste intramedular de poliamida 12 proporcionou consolidação óssea nesse modelo biológico nesse tipo de fratura, não havendo indícios de induzir rejeição.(AU)


Assuntos
Animais , Materiais Biocompatíveis , Materiais Biocompatíveis/efeitos adversos , Galinhas , Fixação Interna de Fraturas/veterinária , Fixação Intramedular de Fraturas/veterinária , Reação Hospedeiro-Enxerto , Nylons
20.
Arq. bras. neurocir ; 37(2): 119-122, 24/07/2018.
Artigo em Inglês | LILACS | ID: biblio-912242

RESUMO

Pituicytoma is a rare tumor that arises from the glial cells of the neurohypophysis. For a long time, it was believed that pituicytomas only appeared in adults. Currently, at least three cases of this entity occurring in children have been reported in the literature. The aim of the present report is to describe the case of a 5-year-old girl who presented to the emergency department with visual disturbances, and the diagnosis was a recurrent pituicytoma. Therefore, the clinical presentation, the radiological features of the tumor, and the corresponding surgical management are described. Additionally, a brief review of the management of this unusual entity was performed.


O pituicitoma é um tumor raro que surge das células gliais da neurohipófise. Durante muito tempo, acreditou-se que os pituicitomas só aparecessem em adultos. Atualmente, pelo menos três casos desta entidade ocorrendo em crianças foram relatados na literatura. O objetivo do presente artigo é descrever o caso de uma menina de 5 anos que chegou à emergência com distúrbios visuais, e o diagnóstico foi um pituicitoma recorrente. A apresentação clínica, as características radiológicas do tumor, e o correspondente manejo cirúrgico foram, portanto, descritos. Além disso, foi realizada uma breve revisão do tratamento desta entidade incomum.


Assuntos
Humanos , Feminino , Pré-Escolar , Pediatria , Neoplasias Hipofisárias , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia
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