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1.
AJR Am J Roentgenol ; 214(6): 1335-1342, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32228328

RESUMO

OBJECTIVE. The clumpy artifact has a high misdiagnosis rate, but the artifact has not been well studied. The aims of this study were to evaluate the frequency and location of clumpy artifacts, the rate of misdiagnosis of clumpy artifacts as gout, and the effects of raising the minimum attenuation value and using a selective photon shield in dual-energy CT (DECT). MATERIALS AND METHODS. Forty patients without gout who underwent foot and ankle DECT were enrolled in this study. Images in both sets were randomly assigned a minimum attenuation of 130 HU or 150 HU. Three radiologists independently checked all images for presence, volume, and location of green color-coded pixelation and graded their findings according to a 4-point confidence scale, frequency, and volume. Misdiagnosis rate and misdiagnosis score were compared using the Wilcoxon signed rank and McNemar tests. RESULTS. In set 1, the frequency of clumpy artifacts in DECT with the minimum attenuation set to 130 HU and 150 HU were 81% and 68%, respectively. For all three readers, the misdiagnosis rate and misdiagnosis score decreased when changing the minimum attenuation from 130 HU to 150 HU. In set 2, with the minimum attenuation set to 130 HU, the frequency of the clumpy artifact was 44%; with the minimum attenuation set to 150 HU, no clumpy artifacts were seen. CONCLUSION. Clumpy artifacts occurred frequently in DECT without a tin filter. Setting the minimum attenuation to the higher value of 150 HU reduced the frequency of clumpy artifacts, and adding a tin filter to DECT greatly reduced their occurrence.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31931556

RESUMO

Objective: To generate synthetic spine magnetic resonance (MR) images from spine computed tomography (CT) using generative adversarial networks (GANs), as well as to determine the similarities between synthesized and real MR images. Methods: GANs were trained to transform spine CT image slices into spine magnetic resonance T2 weighted (MRT2) axial image slices by combining adversarial loss and voxel-wise loss. Experiments were performed using 280 pairs of lumbar spine CT scans and MRT2 images. The MRT2 images were then synthesized from 15 other spine CT scans. To evaluate whether the synthetic MR images were realistic, two radiologists, two spine surgeons, and two residents blindly classified the real and synthetic MRT2 images. Two experienced radiologists then evaluated the similarities between subdivisions of the real and synthetic MRT2 images. Quantitative analysis of the synthetic MRT2 images was performed using the mean absolute error (MAE) and peak signal-to-noise ratio (PSNR). Results: The mean overall similarity of the synthetic MRT2 images evaluated by radiologists was 80.2%. In the blind classification of the real MRT2 images, the failure rate ranged from 0% to 40%. The MAE value of each image ranged from 13.75 to 34.24 pixels (mean, 21.19 pixels), and the PSNR of each image ranged from 61.96 to 68.16 dB (mean, 64.92 dB). Conclusion: This was the first study to apply GANs to synthesize spine MR images from CT images. Despite the small dataset of 280 pairs, the synthetic MR images were relatively well implemented. Synthesis of medical images using GANs is a new paradigm of artificial intelligence application in medical imaging. We expect that synthesis of MR images from spine CT images using GANs will improve the diagnostic usefulness of CT. To better inform the clinical applications of this technique, further studies are needed involving a large dataset, a variety of pathologies, and other MR sequence of the lumbar spine.

3.
Biochem Biophys Res Commun ; 522(3): 731-735, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31791585

RESUMO

Rheumatoid arthritis (RA) is a highly inflammatory autoimmune disease. Although proinflammatory cytokines, including tumor necrosis factor (TNF) and interleukin (IL)-6, play a key role in the pathogenesis of RA, the causes of chronic inflammation are not fully understood. Here, we report that protein phosphatase magnesium-dependent 1A (PPM1A) levels were increased in RA synovial fluid compared with osteoarthritis (OA) synovial fluid and positively correlated with TNF levels. In addition, PPM1A expression was increased in synovial tissue from RA patients and joint tissue from a mouse model of arthritis. Finally, extracellular PPM1A induced inflammation by stimulating macrophages to produce TNF through toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein 88 (MyD88) signaling pathway. Our findings suggest that extracellular PPM1A may contribute to the pathogenesis of RA by functioning as a damage-associated molecular pattern (DAMP) to induce inflammation.

4.
Eur Radiol ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822976

RESUMO

OBJECTIVES: To evaluate the diagnostic performance of dual-energy CT with water-hydroxyapatite (HAP) imaging for bone marrow edema in patients with non-traumatic hip pain. METHODS: Forty patients (mean age, 58 years; 16 male and 24 female) who underwent rapid kVp-switching dual-energy CT and MRI within 1 month between April 2018 and February 2019 with hip pain but no trauma were enrolled. Two radiologists retrospectively evaluated 80 hip joints for the presence, extent (femoral head involved, head and neck, and head to intertrochanter), and severity (mild edema, moderate, severe) of bone marrow edema on dual-energy water-HAP images. Water mass density (mg/cm3) on water-HAP images was determined with region of interest-based quantitative analysis. MRI served as the standard of reference. RESULTS: Sensitivity, specificity, and accuracy of readers 1 and 2 for the identification of bone marrow edema in water-HAP images were 85% and 85%, 93% and 73%, and 89% and 79%, respectively. The area under the receiver operating characteristic curve was 0.96 for reader 1 and 0.91 for reader 2 for differentiation of the presence of edema from no edema. The optimal water mass density to classify the presence of edema for reader 1 was 951 mg/cm3 with 93% sensitivity and 93% specificity and for reader 2 was 957 mg/cm3 with 80% sensitivity and 80% specificity. The more severe the edema, the higher was the mean water density value (p < 0.035). CONCLUSION: Dual-energy water-HAP images showed good diagnostic performance for bone marrow edema in patients with non-traumatic hip pain. KEY POINTS: • Dual-energy water-HAP imaging depicts bone marrow edema in patients with non-traumatic hip pain and may serve as an alternative to MRI in select patients. • A cutoff value of 951 mg/cm 3mean water mass density results in 93% sensitivity and 93% specificity for the detection of bone marrow edema. • The more severe the bone marrow edema, the higher the mean water density value.

5.
J Magn Reson Imaging ; 50(3): 798-809, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30663160

RESUMO

BACKGROUND: A wide range of specificity values for the differentiation of benign and malignant soft-tissue tumors show the limitations of conventional MRI features. The data obtained by quantitative analysis of diffusion-weighted image (DWI) and dynamic contrast-enhanced (DCE) MRIs would provide more objective results, especially in terms of cellularity and perfusion. PURPOSE: To evaluate the diagnostic efficacies of DWI and DCE MRI for the differentiation of malignant and benign soft-tissue tumors. STUDY TYPE: Retrospective. SUBJECTS: In all, 136 patients (68 females, 68 males; age range 18-86 years, mean age 57.2 years) with soft-tissue tumors. FIELD STRENGTH/SEQUENCE: 3 T, DWI, DCE. ASSESSMENT: Tumor sizes, margins, locations, the presence of involvement in bone or neurovascular bundle, peritumoral edema, heterogeneity, and tumor necrosis were investigated on conventional MR images. On DWIs, visual signal drops were assessed and ADC (apparent diffusion coefficient) values were measured. Ktrans , Kep , Ve , and iAUC values, and time-concentration curve (TCC) types were determined using DCE images. STATISTICAL TESTS: The data were statistically analyzed to determine the abilities to differentiate benign and malignant tumors using the chi-square test, two-sample t-test, and receiver operating characteristic (ROC) analysis. RESULTS: Seventy-three cases were malignant and 63 benign. Age (mean ages of benign/malignant tumors, 51.75/61.86 years; P = 0.0002) and gender (F:M = 40:23 [benign], F:M = 28:45 [malignant], P = 0.003) influenced the distinction between benign and malignant. Sizes, margins, neurovascular bundle involvement, peritumoral edema, and heterogeneity of the tumors on conventional MR images and DCE parameters (Ktrans , Kep , Ve , and iAUC, and TCC plots) obtained from focal region of interest within a narrow volume of interest significantly differentiated benign and malignant lesions (all P < 0.0001, except Ve [P = 0.0004]). For DWI with ADC mapping, all ADC values and visually signal drops were also significant (P < 0.0001). DATA CONCLUSION: DWI and DCE-MRI and derived variables were significantly helpful in discriminating benign and malignant soft-tissue tumors complementary to conventional MRI. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:798-809.

6.
Clin Imaging ; 49: 111-116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29232574

RESUMO

PURPOSE: To describe imaging findings in superficial soft tissue lymphomas, especially those located in the skin and subcutaneous layer. MATERIALS AND METHODS: This study included 44 pathologically confirmed superficial lymphoma lesions. Imaging analysis included the size, margin, location, morphology, homogeneity and multiplicity. RESULTS: A nodular form was the most common (21/44, 47.7%) morphology, and of them, 18 demonstrated a streaky appearance. Most of the lesions demonstrated ill-defined margins (26/44, 59.1%) and homogeneous patterns (35/44, 79.5%). CONCLUSIONS: The imaging findings of superficial soft tissue lymphomas were non-specific. However, if images show multiple nodular lesions with ill-defined margins, we should consider this diagnosis.


Assuntos
Linfoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imagem por Ressonância Magnética/métodos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Adulto Jovem
7.
Clin Imaging ; 48: 79-85, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29055275

RESUMO

PURPOSE: To explore associations between prognostic factors and subtypes of invasive breast cancer (IBC) and elasticity values using three-dimensional (3D) and two-dimensional (2D) shear-wave elastography (SWE). MATERIALS AND METHODS: Mean elasticity values (kPa) of 121 IBCs were measured using both 3D and 2D SWE. Associations between these values and prognostic factors and subtypes were analyzed using linear regression model. RESULTS: In both 3D and 2D SWE, larger size and presence of lymphovascular invasion were independent factors influencing higher mean elasticity on multivariate analyses (all p values<0.05). CONCLUSIONS: Using either 3D or 2D SWE, higher mean elasticity values are associated with poor prognostic factors of IBC.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Técnicas de Imagem por Elasticidade/métodos , Elasticidade , Imageamento Tridimensional/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Metástase Linfática/diagnóstico , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
8.
Skeletal Radiol ; 47(3): 407-411, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29038921

RESUMO

Sarcoidosis is an inflammatory disorder that is characterized by the presence of noncaseating granulomas in tissues, involving many organs and tissues. Extra-pulmonary, especially muscular sarcoidosis is a rare condition. The most common location of the muscular sarcoidosis is known to be the proximal muscles of the extremities; however, there have been no cases of diffuse involvement of the chest and abdominal wall muscles. Here, we report a rare muscular sarcoidosis with infiltrative pattern in the chest and abdominal wall muscles and describe the MR imaging findings that were mistaken as lymphoma at initial diagnosis. Although our case did not show characteristic MR findings of muscular sarcoidosis, clinicians or radiologists who are aware of these imaging features can perform early systemic survey for sarcoidosis. Also muscle biopsy is very important to confirm the sarcoidosis and distinguish it from other tumors.


Assuntos
Parede Abdominal/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Doenças Musculares/diagnóstico por imagem , Sarcoidose/diagnóstico por imagem , Doenças Torácicas/diagnóstico por imagem , Parede Abdominal/patologia , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Doenças Musculares/patologia , Sarcoidose/patologia , Doenças Torácicas/patologia
9.
AJR Am J Roentgenol ; 209(6): 1411-1418, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28834445

RESUMO

OBJECTIVE: The purpose of this study was to analyze the clinicopathologic and immunohistochemical features of invasive breast cancers detected only with digital breast tomosynthesis (DBT), compared with those of cancers detected with both DBT and full-field digital mammography (FFDM). MATERIALS AND METHODS: The medical records of 261 women (108 without and 153 with symptoms) with invasive breast cancers who underwent FFDM and DBT between April 2015 and June 2016 were retrospectively reviewed. To assess detectability, all DBT and FFDM images were reviewed independently by three radiologists blinded to clinicopathologic information. The reference standard was established by an unblinded consensus review of all images. Clinicopathologic and immunohistochemical features were analyzed according to the detectability status. RESULTS: Of the 261 cancers, 223 (85.4%) were detected with both DBT and FFDM (both-detected group). Twenty-four cancers (9.2%) not detected with FFDM (DBT-only group) were classified by DBT as a mass (58.3%), architectural distortion (33.3%), or asymmetry (8.3%). The remaining 14 cancers (5.4%) were not detected with either DBT or FFDM (both-occult group). On multivariate analysis, a dense breast parenchyma (p = 0.007), small tumor size (≤ 2 cm; p = 0.027), and luminal A-like subtype (estrogen receptor positive or progesterone receptor positive or both, human epidermal growth factor receptor 2 negative, and Ki-67 expression < 14%; p = 0.008) were significantly associated with the DBT-only group. For 108 screening-detected cancers, a dense breast parenchyma (p = 0.007) and luminal A-like subtype (p = 0.008) also maintained significance. CONCLUSION: The addition of DBT to FFDM in screening would aid in the detection of less-aggressive subtypes of invasive breast cancers in women with dense breasts.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Mamografia/métodos , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Detecção Precoce de Câncer , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Korean J Radiol ; 17(5): 565-80, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27587946

RESUMO

MR findings of early infectious spondylodiscitis are non-specific and may be confused with those of other conditions. Therefore, it is important to recognize early MR signs of conditions, such as inappreciable cortical changes in endplates, confusing marrow signal intensities of vertebral bodies, and inflammatory changes in paraspinal soft tissues, and subligamentous and epidural spaces. In addition, appreciation of direct inoculation, such as in iatrogenic spondylodiscitis may be important, because the proportion of patients who have undergone recent spine surgery or a spinal procedure is increasing. In this review, the authors focus on the MR findings of early spondylodiscitis, atypical findings of iatrogenic infection, and the differentiation between spondylodiscitis and other disease entities mimicking infection.


Assuntos
Discite/diagnóstico por imagem , /diagnóstico por imagem , Diagnóstico Diferencial , Discite/microbiologia , Diagnóstico Precoce , Humanos , Imagem por Ressonância Magnética/métodos
11.
Br J Radiol ; 89(1066): 20160302, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27459249

RESUMO

OBJECTIVE: To determine the diagnostic availability of dynamic contrast-enhanced (DCE) and diffusion-weighted (DW) MR images for evaluating residual tumours at short-term follow-up after unplanned excision of malignant soft-tissue tumours. METHODS: From January 2013 to September 2014, 38 patients underwent first follow-up MRI, including DCE and DW imaging (DWI), within 3 months of unplanned malignant soft-tissue tumour excision. The presence or absence of definite nodule formation, focal fluid/haematoma collection, oedema and fascial thickening around or at tumour beds were evaluated using conventional MR images. The volume transfer constant between blood plasma and extracellular/extravascular space (EES) (Ktrans), rate constant between EES and blood plasma (Kep), volume of EES space per unit volume of tissue and initial area under the concentration curve (iAUC) values with time-concentration curve (TCC) plots were obtained on DCE images, and apparent diffusion coefficient (ADC) values were measured on ADC maps. All data were statistically analyzed. RESULTS: Of the 21 patients who underwent re-excision, 12 patients had a residual tumor and 9 did not. All conventional MRI variables, except definite nodule formation, were insignificantly related to the presence of residual tumour. However, ADC values were found to be significantly associated with the presence of residual tumour, as were the DCE MRI variables, Ktrans, Kep and iAUC. In particular, TCC pattern and Kep were most significantly associated with residual tumour. CONCLUSION: Additional DCE images may be useful for determining the presence of residual tumours in tumour beds during short-term follow-up after inadequate malignant soft-tissue tumour excision. ADVANCES IN KNOWLEDGE: The addition of DCE MRI and quantitative analysis of the images obtained might be useful for determining the presence of residual tumour in a tumour bed during short-term follow-up after inadequate excision of a malignant soft-tissue tumour, although DWI was also found to be helpful.


Assuntos
Imagem por Ressonância Magnética/métodos , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Feminino , Seguimentos , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Reoperação , Resultado do Tratamento
12.
Skeletal Radiol ; 40(11): 1421-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21190020

RESUMO

OBJECTIVE: The purpose of this article was to evaluate the radiologic findings of adult pelvis and appendicular skeletal Langerhans cell histiocytosis (LCH), emphasizing the CT and MR findings. MATERIALS AND METHODS: The images of nine patients with pathologically proven LCH (five men and four women; mean age, 37.11 years) were retrospectively reviewed. Imaging analysis was confined to the long and flat bones. CT scans were performed in five patients and MR imaging was performed in eight. Images were assessed for the following features on CT and MRI: the location and number of lesions; the presence of cortical destruction, endosteal scalloping, and a periosteal reaction on CT or MRI; the margin of soft tissue masses, the presence of bone marrow edema, and a "budding" appearance on MRI; and the presence of sclerotic margins or septations on CT. RESULTS: The involved skeletal sites were the pelvis (seven), femurs (five), humeri (two), tibias (two), fibula (one), clavicle (one), scapula (one), and sternum (one). Endosteal scalloping, a periosteal reaction, and a budding appearance were common on MRI or CT images. Although cortical destruction and the soft tissue lesion formation were rare, soft tissue masses had well-defined margins. CONCLUSIONS: Endosteal scalloping and a budding appearance with a periosteal reaction on CT and MRI may be helpful signs for differentiation of LCH from malignant tumors in adults.


Assuntos
Doenças Ósseas/diagnóstico por imagem , Ossos da Extremidade Superior/diagnóstico por imagem , Histiocitose de Células de Langerhans/diagnóstico por imagem , Ossos da Perna/diagnóstico por imagem , Ossos Pélvicos/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Doenças Ósseas/diagnóstico , Ossos da Extremidade Superior/patologia , Feminino , Histiocitose de Células de Langerhans/diagnóstico , Humanos , Ossos da Perna/patologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ossos Pélvicos/patologia
13.
Skeletal Radiol ; 39(10): 1035-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20182711

RESUMO

Fibrous hamartomas of infancy (FHIs) are benign, poorly-circumscribed, soft tissue growths presenting during the first 2 years of life and characteristically affecting the axilla, upper arm, upper trunk, inguinal region, and external genital area. Involvement of the hands and feet is extremely rare. We report a case of FHI unusually occurring in a deep portion of the hand. MRI revealed atypical features similar to that of a vascular malformation, hemangioma, fibromatosis, or neurofibromatosis of the hand. Partial resection of the mass was performed to correct the contracture of the second finger and an additional operation was not performed because of the benign nature of FHIs.


Assuntos
Hamartoma/diagnóstico , Mãos/patologia , Imagem por Ressonância Magnética/métodos , Neoplasias de Tecidos Moles/diagnóstico , Diagnóstico Diferencial , Hamartoma/cirurgia , Mãos/cirurgia , Humanos , Lactente , Masculino , Neoplasias de Tecidos Moles/cirurgia
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