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2.
J Comput Assist Tomogr ; 44(1): 7-12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939875

RESUMO

OBJECTIVE: The aim of the study was to investigate the feasibility of coronary computed tomography (CT) angiography with a low kilovoltage peak scan and a refined scan timing prediction using a small contrast medium (CM) dose. METHODS: In protocol A, 120-kVp scanning and a standard CM dose were used. The scan timing was fixed. In protocol B, 80 kVp and a 60% CM dose were used. The scan timing was determined according to the interval from the CM arrival to the peak time in the ascending aorta. We measured the CT number and recorded the radiation dose. RESULTS: Higher CT numbers were observed in the left circumflex (proximal, P = 0.0235; middle, P = 0.0007; distal, P < 0.0001) in protocol B compared with protocol A. The radiation dose in protocol B was significantly lower than in protocol A (2.2 ± 0.9 vs 4.3 ± 1.7 mSv). CONCLUSIONS: Low-contrast, low-radiation dose, high-image quality coronary CT angiography can be performed with low kilovoltage peak scanning and a refined scan timing prediction.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Idoso , Cálculos da Dosagem de Medicamento , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos
3.
J Comput Assist Tomogr ; 44(1): 70-74, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939885

RESUMO

PURPOSE: The aim of this study was to determine the valuable magnetic resonance imaging (MRI) features of sinonasal metastatic clear-cell renal cell carcinoma (cc-RCC), especially focusing on its dynamic-enhanced characteristics. METHODS: The conventional and dynamic-enhanced MRI findings of 8 patients with histopathologically confirmed sinonasal metastatic cc-RCC were reviewed by 2 radiologists. The control group of 8 patients with capillary hemangioma underwent the same MRI protocol. RESULTS: Metastatic cc-RCCs arose from the nasoethmoid region, maxillary sinus, posterior ethmoid and sphenoid sinus, and nasal cavity in 2 patients in each. These lesions were well circumscribed and the mean maximum dimension was 42 mm. The signal intensity of these lesions was isointense to brain stem on both MR T1- and T2-weighted images. All metastatic tumors showed vivid enhancement on enhanced T1-weighted image. Multiple flow voids within these metastatic lesions were identified in 6 patients. Peripheral cyst was detected around the metastatic tumor in 4 patients. Metastatic cc-RCCs exhibited a characteristic type 4 time intensity curve (TIC) similar to that of the internal carotid artery, whereas capillary hemangiomas showed a type 3 TIC on dynamic-enhanced MRI. CONCLUSIONS: A hypervascular mass with the characteristic type 4 TIC in the sinonasal region is highly suggestive of a metastatic cc-RCC.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Cavidade Nasal/patologia , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Neoplasias dos Seios Paranasais/secundário , Idoso , Carcinoma de Células Renais/patologia , Detecção Precoce de Câncer , Feminino , Humanos , Neoplasias Renais/patologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/diagnóstico por imagem , Neoplasias dos Seios Paranasais/patologia , Período Pré-Operatório , Intensificação de Imagem Radiográfica
4.
J Comput Assist Tomogr ; 44(1): 78-82, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939886

RESUMO

OBJECTIVE: This study aimed to evaluate virtual monochromatic images (VMIs) obtained using dual-layer dual-energy computed tomography (CT) for breast carcinoma. METHODS: We retrospectively enrolled 28 patients with breast cancer who were pathologically diagnosed using dual-layer dual-energy CT. Virtual monochromatic images (40-200 keV) were generated. We compared CT number, image noise, contrast, and contrast-to-noise ratio (CNR) between VMIs with the highest CNR and conventional CT images. We performed qualitative image analysis between VMIs at optimized energy and conventional CT images. RESULTS: Image noise of VMIs was not significantly different from that of the conventional CT images. As the x-ray energy decreased, CNR increased. The 40-keV VMIs were highest CNR and higher than that of the conventional CT images. In qualitative image analysis, the 40-keV images were significantly higher than conventional CT images. CONCLUSION: Both qualitative and quantitative analyses showed that the image quality of VMIs at 40 keV was significantly higher than that of conventional CT images.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Razão Sinal-Ruído
5.
Radiol Med ; 125(2): 145-154, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31701292

RESUMO

INTRODUCTION: This study aimed to evaluate the accuracy of both digital complete and small portion of panoramic radiography (PAN) in the detection of clinically/surgically confirmed asymptomatic apical periodontitis (AP) lesions with and without endodontic treatment. METHODS: A total of 480 patients/teeth including 120 AP with and without endodontic treatment, and 120 healthy periapex with and without endodontic treatment were detected via CBCT using the periapical index system. Each diseased and healthy patient underwent PAN first and a CBCT scan within 40 days. All 480 cases were assessed by four different methods, as follows: complete PAN with clinical examination of each tooth available and not available, respectively, and small portion of PAN in which a root with crown and root without crown were displayed, respectively. Periapical index system was also used to assess AP by PAN. Accuracy for both complete and small portion of PAN with respect to CBCT was analyzed. RESULTS: The overall accuracy of the four methods for teeth with endodontic treatment (73.4) was higher than teeth without endodontic treatment (66.6). Accuracy of complete PAN and portion of PAN was 71.3 and 68.7, respectively. As regards teeth without endodontic treatment, accuracy was higher for complete PAN in the upper/lower incisive area and for small portion of PAN in the upper molar area. No difference was found in teeth with endodontic treatment. CONCLUSION: Complete and small portion of PAN showed greater accuracy in the upper/lower incisive area and upper molar area of untreated teeth, respectively, whereas no difference was found in treated teeth.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Periodontite Periapical/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador , Radiografia Panorâmica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite Periapical/terapia
7.
Radiol Clin North Am ; 58(1): 93-103, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731905

RESUMO

This article describes an approach to analyzing the distribution of intravenous contrast on chest computed tomography and illustrates the various pathologies and pitfalls that may be encountered by the imager, especially in the hospitalized patient. Understanding normal and abnormal distribution of intravenous contrast can be used as a clue to detect alterations in physiology and flow.


Assuntos
Meios de Contraste , Cardiopatias/diagnóstico por imagem , Pacientes Internados , Embolia Pulmonar/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Tomografia Computadorizada por Raios X/métodos , Coração/diagnóstico por imagem , Hospitalização , Humanos , Pulmão/diagnóstico por imagem , Radiografia Torácica/métodos
8.
Eur Radiol ; 30(1): 163-174, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31359127

RESUMO

OBJECTIVES: To assess the impact of recently developed respiratory motion correction software on contrast-enhanced cone beam CT angiography (CBCT-a) for intraprocedural image guidance during intra-arterial liver-directed therapy. METHODS: From 2015 to 2017, two groups of patients who underwent intra-arterial liver-directed therapy with (breathing, n = 30) or without (still, n = 30) significant respiratory motion artifacts were retrospectively included. All CBCT-a were processed with and without dedicated respiratory motion correction software. Four readers independently assessed the following in both reconstructions (motion correction ON and OFF): (1) overall image quality on a 0-to-5 point scale, and (2) presence of relevant peri-procedural information on tumor and vasculature (overall vessel geometry, visibility of extrahepatic vessels, target tumor conspicuity, visibility of tumor feeders). RESULTS: Motion correction increased the average image quality in the breathing group from 2.0 ± 0.9 to 2.9 ± 1.0 (p < 0.01). The visibility of vessel geometry, extrahepatic vessels, and tumor feeders was significantly improved for all readers, and tumor conspicuity was improved for three readers. The average image quality was not significantly different between reconstructions in the still group (motion correction ON and OFF), for any of the readers (4.0 ± 0.6 vs 4.2 ± 0.6; p = 0.12). There was no change in the visibility of vessel geometry, extrahepatic vessels, tumor feeders, or tumor conspicuity for the four readers using the respiratory motion correction software in this group. CONCLUSIONS: Using the dedicated respiratory motion correction software during intra-arterial liver-directed procedures increases the visualization of relevant peri-procedural information and image quality in CBCT-a corrupted by respiratory motion artifacts without affecting these elements in still CBCT-a. KEY POINTS: • The use of respiratory motion correction software could reduce the need for cone beam CT angiography acquisition retake. • Motion correction software significantly increases the visibility of vessel geometry, extrahepatic vessels, and tumor feeders, as well as tumor conspicuity in cone beam CT angiography corrupted by respiratory motion artifacts. • The use of respiratory motion correction software on cone beam CT angiography uncorrupted by respiratory motion artifact does not result in decreased image quality.


Assuntos
Artefatos , Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Hepáticas , Intensificação de Imagem Radiográfica/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Quimioembolização Terapêutica/métodos , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Respiração , Estudos Retrospectivos , Software
9.
Eur Radiol ; 30(1): 547-557, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31396730

RESUMO

OBJECTIVES: To determine the integrative value of contrast-enhanced computed tomography (CECT), transcriptomics data and clinicopathological data for predicting the survival of bladder urothelial carcinoma (BLCA) patients. METHODS: RNA sequencing data, radiomics features and clinical parameters of 62 BLCA patients were included in the study. Then, prognostic signatures based on radiomics features and gene expression profile were constructed by using least absolute shrinkage and selection operator (LASSO) Cox analysis. A multi-omics nomogram was developed by integrating radiomics, transcriptomics and clinicopathological data. More importantly, radiomics risk score-related genes were identified via weighted correlation network analysis and submitted to functional enrichment analysis. RESULTS: The radiomics and transcriptomics signatures significantly stratified BLCA patients into high- and low-risk groups in terms of the progression-free interval (PFI). The two risk models remained independent prognostic factors in multivariate analyses after adjusting for clinical parameters. A nomogram was developed and showed an excellent predictive ability for the PFI in BLCA patients. Functional enrichment analysis suggested that the radiomics signature we developed could reflect the angiogenesis status of BLCA patients. CONCLUSIONS: The integrative nomogram incorporated CECT radiomics, transcriptomics and clinical features improved the PFI prediction in BLCA patients and is a feasible and practical reference for oncological precision medicine. KEY POINTS: • Our radiomics and transcriptomics models are proved robust for survival prediction in bladder urothelial carcinoma patients. • A multi-omics nomogram model which integrates radiomics, transcriptomics and clinical features for prediction of progression-free interval in bladder urothelial carcinoma is established. • Molecular functional enrichment analysis is used to reveal the potential molecular function of radiomics signature.


Assuntos
Nomogramas , Tomografia Computadorizada por Raios X/métodos , Transcriptoma/genética , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/genética , Adulto , Meios de Contraste , Feminino , Humanos , Masculino , Prognóstico , Intensificação de Imagem Radiográfica/métodos , Fatores de Risco , Análise de Sobrevida , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia
10.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 75(12): 1420-1425, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31866640

RESUMO

In radiography with anti-scatter grid, it is important to make sure that the X-ray beam direct exactly perpendicular to the grid plane. However, it is so difficult to ensure in mobile radiography. An optical sight to ensure X-ray alignment in mobile radiography with anti-scatter grid was devised. The device measures the X-ray beam angle respect to the grid plane by utilizing collimator-lamp. Computed radiography of water phantom on inclined bedding with anti-scatter grid (6 : 1) were done by aid of devised optical sight 20 times. The result showed that the average alignment error of the radiographies by aid of devised optical sight was within 1°, and the maximum error was<2°.


Assuntos
Invenções , Intensificação de Imagem Radiográfica , Imagens de Fantasmas , Radiografia , Radiografia Torácica , Espalhamento de Radiação , Raios X
11.
J Comput Assist Tomogr ; 43(6): 877-883, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31688248

RESUMO

PURPOSE: This study aimed to prospectively compare the image quality and visibility of urinary stone on computed tomographic (CT) images at multiple radiation exposure levels from the same patient reconstructed with sinogram-affirmed iterative reconstruction (SAFIRE). METHODS: This study included 760 patients with urinary stone who underwent CT with simultaneous acquisition at 6 exposures per patient (100% filtered back projection, 75%, 50%, 37.5%, 25%, and 12.5% SAFIRE). Two radiologists independently assessed overall image quality, noise, and stone visibility by using a 5-point scale. Quantitative measurements, including the CT number, image noise, signal-to-noise ratio, contrast-to-noise ratio (CNR), and corresponding figure of merit (FOM), were compared for 100% versus 5 other radiation doses. RESULTS: Qualitative overall image quality, noise, and stone visibility according to the location were not inferior at 37.5% exposure compared with 100% exposure, except for the visualization of smaller stones <3 mm. The signal-to-noise ratio and CNR of CT images were increased at 50% exposure compared with 100% exposure. Computed tomographic images at 37.5% exposure reconstructed with SAFIRE had significantly more noise and a lower CNR compared with CT images reconstructed with filtered back projection, based on FOMnoise and FOMCNR. The size-specific dose estimation was 4.1 ± 0.8 mGy at 37.5% exposure. CONCLUSION: Computed tomography performed at 37.5% exposure with SAFIRE may be diagnostically acceptable for the detection of clinically relevant stone.


Assuntos
Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Cálculos Urinários/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X , Adulto Jovem
12.
J Comput Assist Tomogr ; 43(6): 948-952, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31688249

RESUMO

PURPOSE: This study aimed to evaluate the image quality and degree of metal artifact reduction using the new-generation gemstone spectral imaging (GSI) and metal artifact reduction software (MARs) and to demonstrate the optimal monochromatic energy level for dual-energy cerebral computed tomography angiography (CTA) in patients with intracranial aneurysm after endovascular treatment. MATERIAL AND METHODS: A total of 20 patients with cerebral aneurysms treated with coils or clips underwent CTA using gemstone spectral computed tomography. Artifact index was calculated at each energy level with and without MARs. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated on all axial images with MARs; subjective evaluation was done by using a 4-point scale and a 3-point scale for assessing noise and vessel contrast, respectively, and compared between the monochromatic energy levels. RESULTS: The artifact index value of group GSI-MARs was significantly lower than that of group GSI at each monochromatic energy level (all, P < 0.01). Contrast-to-noise ratio and SNR of the parent arteries decreased as the energy increased from 40 to 140 keV in group GSI-MARs (all, P < 0.01). Signal-to-noise ratio and CNR between each 2 adjacent monochromatic energy level showed significant difference (all, P < 0.01). Subjective evaluation showed that a monochromatic energy level between 40 and 70 keV provided the optimal image quality. CONCLUSION: Gemstone spectral imaging with MARs could reduce metal artifacts and improve the image quality of cerebral CTA after coil or clip treatment. The new generation of GSI could provide better CNR and SNR at lower energy level, and the best image quality was obtained at energy level 40 to 70 keV for GSI-MARs.


Assuntos
Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Intensificação de Imagem Radiográfica/métodos , Adulto , Idoso , Artefatos , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estudos Retrospectivos , Razão Sinal-Ruído , Software
13.
J Comput Assist Tomogr ; 43(6): 943-947, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31738210

RESUMO

OBJECTIVE: Silent magnetic resonance angiography (MRA) was compared with time-of-flight (TOF)-MRA in imaging of arteriovenous malformations (AVMs) of the brain. METHODS: Thirty-five consecutive patients with AVMs of the brain were included. Quantitative analyses were performed by measuring both signal-to-noise ratio and contrast-to-noise ratio of the nidus. Qualitative analysis (scores 1-4) was performed by evaluating depictions of feeding arteries and draining veins independently by 2 reviewers. RESULTS: Both signal-to-noise ratio and contrast-to-noise ratio in TOF-MRA were significantly higher than those in silent MRA. For both feeders and drainers, scores were significantly higher in silent MRA than in TOF-MRA for both reviewers. Interrater agreement was higher in silent MRA than in TOF-MRA. CONCLUSIONS: Silent MRA visualized feeders and drainers in AVMs significantly better than did TOF-MRA. Interrater agreement was also better in silent MRA.


Assuntos
Angiografia Digital/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Adolescente , Adulto , Feminino , Humanos , Imagem Tridimensional , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica , Razão Sinal-Ruído , Adulto Jovem
14.
Medicine (Baltimore) ; 98(47): e17902, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31764788

RESUMO

PURPOSE: To assess the probability of achieving optimal contrast enhancement in 100 kVp and 120 kVp-protocol on hepatic computed tomography (CT) scans. MATERIALS AND METHODS: We enrolled 200 patients in a retrospective cohort study. Hundred patients were scanned with 120 kVp setting, and other 100 patients were scanned with 100 kVp setting. We measured the CT number in the abdominal aorta and hepatic parenchyma on unenhanced scans and hepatic arterial phase (HAP)-, and portal venous phase (PVP). The aortic enhancement at HAP and the hepatic parenchymal enhancement at PVP were compared between the two scanning protocols. Bayesian inference was used to assess the probability of achieving optimal contrast enhancement in each protocol. RESULTS: The Bayesian analysis indicated that when 100 kVp-rotocol was used, the probability of achieving optimal aortic enhancement (>280 HU) was 98.8% ±â€Š0.6%, whereas it was 88.7% ±â€Š2.5% when 120 kVp-protocol was used. Also, the probability of achieving optimal hepatic parenchymal enhancement (>50 HU) was 95.3% ±â€Š1.5%, whereas it was 64.7% ±â€Š3.8% when 120 kVp-protocol was used. CONCLUSION: Bayesian inference suggested that the post-test probability of optimal contrast enhancement at hepatic dynamic CT was lower under the 120 kVp than the 100 kVp-protocol.


Assuntos
Meios de Contraste , Fígado/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Teorema de Bayes , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Magreza
15.
Radiol Med ; 124(12): 1229-1237, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31773458

RESUMO

The aim of our study was to assess the performance of contrast-enhanced digital mammography (CEDM) in the preoperative loco-regional staging of invasive lobular carcinoma (ILC) patients, about the valuation of the extension of disease and in measurement of lesions. Then, we selected retrospectively, among the 1500 patients underwent to CEDM at the Breast Diagnostics Department of the Careggi University Hospital of Florence and the National Cancer Institute of Milan from September 2016 to November 2018, 31 women (mean age 57.1 aa; range 41-78 aa) with a definitive histological diagnosis of ILC. CEDM has proved to be a promising imaging technique, being characterized by a sensitivity of 100% in the detection of the index lesion, and of 84.2% in identifying any adjunctive lesions: It was the presence of a non-mass enhancement (NME) to lower the sensitivity of the technique (25% vs. 100% for mass-like enhancements or a mass closely associated with a NME). Specificity in the characterization of additional lesions was 66.7%, and the diagnosis of the extension of disease was correct in 77.4% of cases: NME also led to a decrease in diagnostic accuracy in the evaluation of disease extension up to 40% versus 85% for masses and 80% for masses associated with NME (M/NME). Moreover, in 12/31 (38.7%), CEDM allowed to correctly identify lesions not shown by mammography + ultrasonography + tomosynthesis: In the half of these (6/12), there was a multicentricity, thus allowing an adequate surgical planning change. CEDM was also very accurate in analyzing the maximum diameter of the masses, while it was much less reliable in the case of the M/NME and pure NME. In conclusion, CEDM is a new promising imaging technique in the loco-regional preoperative staging and in the evaluation of disease extension for ILC, especially in case of mass enhancement lesions.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Lobular/diagnóstico por imagem , Meios de Contraste , Iohexol/análogos & derivados , Mamografia/métodos , Adulto , Idoso , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Carcinoma Lobular/química , Carcinoma Lobular/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Cuidados Pré-Operatórios , Intensificação de Imagem Radiográfica/métodos , Padrões de Referência , Estudos Retrospectivos , Sensibilidade e Especificidade , Carga Tumoral , Ultrassonografia Mamária
16.
Eur J Radiol ; 120: 108698, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31600640

RESUMO

PURPOSE: The aim of the study is to explore the patient's and scan's parameters that affect the iodine concentration in the abdomen using dual energy computed tomography (DECT) in an oncologic population. METHOD: This is a retrospective study with consecutive patients with different cancers who underwent a single-source DECT (ssDECT) examinations at our institution between years 2015 and 2017. On axial IODINE images, the radiologist manually drew a circular ROI along the inner contour of the aorta. Mean iodine concentration and ROI areas were recorded. Body mass index for every patient was recorded. Descriptive statistics were summarized for iodine concentration and patient/scan characteristics. Linear regression was used to examine associations between iodine concentration in aorta and studied characteristics. Statistical significance was set at a p value < 0.05. RESULTS: The univariate analysis, showed a statistically significant association between iodine concentration within the aorta and the area of ROI (Estimated Coefficient ß: -0.013), the rate of injection (Estimated Coefficient ß: 2.09), the acquisition time (Estimated Coefficient ß: -0.195). In multivariable analysis iodine concentration in the aorta increased with higher rate of injection (4 ml/sec), smaller ROI area and lower BMI. CONCLUSION: Our results showed how iodine concentration is highly dependent on some intrinsic and extrinsic parameters of the examination. These parameters should be taken into account since lower concentration of iodine decrease contrast-to-noise ratio, and in longitudinal follow up studies, they would affect iodine quantitive assessments in cancer patients with frequent chemotherapy-induced variations in BMI and cardiac function.


Assuntos
Meios de Contraste/farmacocinética , Iodo/farmacocinética , Neoplasias/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Aorta/metabolismo , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Urology ; 134: 84-89, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585199

RESUMO

OBJECTIVE: To investigate computed tomography (CT) texture analysis of the bladder wall as a predictor of urodynamics findings in adult patient with spina bifida. METHODS: A single-center prospective trial was conducted from March 2015 to March 2017 including all consecutive adult spina bifida patients seen for urodynamic testing. A contrast-enhanced abdominal CT was systematically performed in all patients during the same visit. Texture features of the bladder wall related to the gray-level histogram and gray-level co-occurrence were evaluated on CT images. Multivariate analysis was performed to identify independent predictors of poor bladder compliance and detrusor overactivity among clinical and texture parameters. RESULTS: Fourty patients were included. The Lasso penalized logistic regression analysis identified 2 texture parameters as potential predictors of poor bladder compliance: Skewness (coefficient weight, -1.81) and S.1.1.SumVarnc (coefficient weight, -3.52). Multivariate logistic regression analysis confirmed skewness (odds ratio [confidence interval 95%] = 0.40 [0.14, 0.97], P = .04) as an independent predictor of poor bladder compliance. The Lasso penalized logistic regression analysis identified one texture parameters as potential predictor of detrusor overactivity: Kurtosis (coefficient weight, -3.52), which was confirmed in multivariate logistic regression analysis (odds ratio [confidence interval 95%] = 1.12 [1.01, 1.55], P = .02). CONCLUSION: Our findings demonstrate that CT texture analysis of the bladder wall might be an interesting tool to identify spina bifida patients with high risk urodynamic features.


Assuntos
Disrafismo Espinal , Tomografia Computadorizada por Raios X/métodos , Bexiga Urinária Hiperativa , Bexiga Urinária , Urodinâmica , Adulto , Feminino , França , Humanos , Masculino , Estudos Prospectivos , Intensificação de Imagem Radiográfica/métodos , Disrafismo Espinal/complicações , Disrafismo Espinal/diagnóstico , Disrafismo Espinal/fisiopatologia , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/fisiopatologia , Bexiga Urinária Hiperativa/diagnóstico , Bexiga Urinária Hiperativa/etiologia , Bexiga Urinária Hiperativa/fisiopatologia
18.
Medicine (Baltimore) ; 98(39): e17280, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574843

RESUMO

BACKGROUND: This study will aim to evaluate the diagnostic accuracy of digital X-ray radiogrammetry (DXR) on hand bone loss (HBL) for rheumatoid arthritis (RA). METHODS: In this study, we will search the literature from PubMed, EMBASE, Cochrane Library, PsycINFO, Web of Science, Google Scholar, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, and WANFANG from the inception to June 1, 2019 without language restrictions. All case-controlled studies on assessing diagnostic accuracy of DXR on HBL for diagnosis of RA will be included. Quality Assessment of Diagnostic Accuracy Studies tool will be used for eligible studies. We will apply RevMan V.5.3 software and Stata V.12.0 software for statistical analysis. RESULTS: We will evaluate diagnostic accuracy of DXR on HBL in patients with RA by assessing the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. CONCLUSION: This study will detect the diagnostic accuracy of DXR evaluation on HBL in patients with RA. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019139489.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Doenças Ósseas Metabólicas/diagnóstico por imagem , Densitometria/estatística & dados numéricos , Intensificação de Imagem Radiográfica/métodos , Radiografia/estatística & dados numéricos , Artrite Reumatoide/complicações , Doenças Ósseas Metabólicas/etiologia , Estudos de Casos e Controles , Densitometria/métodos , Progressão da Doença , Feminino , Ossos da Mão/diagnóstico por imagem , Humanos , Masculino , Radiografia/métodos , Projetos de Pesquisa , Índice de Gravidade de Doença , Revisão Sistemática como Assunto
19.
Phys Med ; 64: 238-244, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31515025

RESUMO

OBJECTIVE: To investigate the impact of image processing algorithms on image quality of digital radiographs. This study was motivated from a case of a patient with metallic hip implant, where the anatomy around the implant was misrepresented, due to failure of the processing algorithm. MATERIALS & METHODS: A quality control phantom was imaged using a digital radiographic unit and the standard examination protocol for Pelvis anteroposterior (AP) projection. The original image was reprocessed with all available selections of Diamond View, which is a processing algorithm for optimizing image quality of different anatomic regions. The same procedure was repeated for two other examination protocols, Femur AP and Hip AP, which differ in terms of harmonization kernel and gain, and look up table settings. The whole procedure was repeated with a Pb strip, 2 cm wide and 3 mm thick, positioned close to the right phantom edge, in order to simulate a metallic hip implant. Using ImageJ a number of regions of interest (ROIs) were positioned on the phantom images and the impact of processing parameters on certain image characteristics and image quality indices was evaluated. RESULTS: Processing parameters have a strong impact on image characteristics, but in terms of image quality, differences between images with and without the implant are small. Exception is the regions in the vicinity of the implant, where larger differences, that could affect diagnosis, were observed. CONCLUSION: In case of doubt, additional processing with settings which minimize the risk of anatomic misrepresentation should be used.


Assuntos
Algoritmos , Prótese de Quadril , Processamento de Imagem Assistida por Computador , Metais , Intensificação de Imagem Radiográfica , Humanos , Imagens de Fantasmas
20.
Artigo em Japonês | MEDLINE | ID: mdl-31548465

RESUMO

OBJECTIVES: The aim of this study was to evaluate an influence of post-processing scatter correction in portable abdominal radiography using a low ratio anti-scatter grid (grid). METHODS: To assess tube voltage on portable abdominal radiography, a burger phantom was used to measure for inverse of image quality figure (IQFinv). For evaluation of the influence on using or not the grid, IQFinv were measured. Abdominal phantom radiographies were assessed subjectively, in random order, by six radiologic technologists. The radiographies were performed without scatter correction [IG (-)] and with scatter correction at equivalent for grid ratio 6 [IG (6)] and 8 [IG (8)]. RESULTS: There was no significant decrease in IQFinv with 75 and 80 kV in comparison of 70 kV. Even processing scatter correction, IQFinv with using the grid was significantly higher than that without using the grid. The ability to detect nasogastric tube and stomach gas were significantly better in the scatter correction. Deviation index for IG (6) and IG (8) were significantly lower than that of IG (-). DISCUSSION: Portable abdominal radiographies will be improved image quality by utilizing scatter correction, although, it is necessary to consider the scatter correction processing as this may significant decrease deviation index in the practical situation. CONCLUSION: The post-processing scatter correction should be useful for detection nasogastric tube and stomach gas in portable abdominal radiography.


Assuntos
Intensificação de Imagem Radiográfica , Radiografia Abdominal , Humanos , Imagens de Fantasmas , Radiografia Abdominal/métodos , Radiografia Torácica , Distribuição Aleatória , Espalhamento de Radiação
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