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1.
Eur J Pediatr ; 183(5): 2285-2300, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38416256

RESUMO

Prenatal assessment of lung size and liver position is essential to stratify congenital diaphragmatic hernia (CDH) fetuses in risk categories, guiding counseling, and patient management. Manual segmentation on fetal MRI provides a quantitative estimation of total lung volume and liver herniation. However, it is time-consuming and operator-dependent. In this study, we utilized a publicly available deep learning (DL) segmentation system (nnU-Net) to automatically contour CDH-affected fetal lungs and liver on MRI sections. Concordance between automatic and manual segmentation was assessed by calculating the Jaccard coefficient. Pyradiomics standard features were then extracted from both manually and automatically segmented regions. The reproducibility of features between the two groups was evaluated through the Wilcoxon rank-sum test and intraclass correlation coefficients (ICCs). We finally tested the reliability of the automatic-segmentation approach by building a ML classifier system for the prediction of liver herniation based on support vector machines (SVM) and trained on shape features computed both in the manual and nnU-Net-segmented organs. We compared the area under the classifier receiver operating characteristic curve (AUC) in the two cases. Pyradiomics features calculated in the manual ROIs were partly reproducible by the same features calculated in nnU-Net segmented ROIs and, when used in the ML procedure, to predict liver herniation (both AUC around 0.85).          Conclusion: Our results suggest that automatic MRI segmentation is feasible, with good reproducibility of pyradiomics features, and that a ML system for liver herniation prediction offers good reliability.          Trial registration: https://clinicaltrials.gov/ct2/show/NCT04609163?term=NCT04609163&draw=2&rank=1 ; Clinical Trial Identification no. NCT04609163. What is Known: • Magnetic resonance imaging (MRI) is crucial for prenatal congenital diaphragmatic hernia (CDH) assessment. It enables the quantification of the total lung volume and the extent of liver herniation, which are essential for stratifying the severity of CDH, guiding counseling, and patient management. • The manual segmentation of MRI scans is a time-consuming process that is heavily reliant upon the skill set of the operator. What is New: • MRI lung and liver automatic segmentation using the deep learning nnU-Net system is feasible, with good Jaccard coefficient values and satisfactory reproducibility of pyradiomics features compared to manual results. • A feasible ML system for predicting liver herniation could improve prenatal assessments and CDH patient management.


Assuntos
Hérnias Diafragmáticas Congênitas , Fígado , Pulmão , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Feminino , Reprodutibilidade dos Testes , Gravidez , Pulmão/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/patologia , Diagnóstico Pré-Natal/métodos , Aprendizado Profundo , Hepatopatias/diagnóstico por imagem , Aprendizado de Máquina
2.
Minerva Urol Nephrol ; 74(1): 29-37, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33016030

RESUMO

BACKGROUND: The aim of this paper was to compare the accuracy of multiple abbreviated multiparametric magnetic resonance imaging (mpMRI)-derived protocols in detecting clinically significant prostate cancer (csPCa). METHODS: One hundred and eight men undergoing staging 3.0T mpMRI with a Prostate Imaging - Reporting and Data System version 2 (PI-RADSv2)-compliant protocol before radical prostatectomy (RP) were retrospectively evaluated. Two readers (R1, R2) independently analyzed mpMRI, assigning a PI-RADSv2 category to each observation as appearing on each examination sequence. A study coordinator assessed final PI-RADSv2 category by combining readers' assignments according to four protocols: short MRI (sMRI) (diffusion-weighted imaging + axial T2-weighted imaging), contrast-enhanced short MRI (cesMRI) (sMRI + dynamic contrast-enhanced [DCE] imaging), biparametric MRI (diffusion-weighted imaging + multiplanar T2-weigthed imaging), and mpMRI. Using RP pathology as the reference standard for csPCa, we calculated the per-lesion cancer detection rate (CDR) and false discovery rate (FDR) for each MRI protocol (cut-off PI-RADSv2 category ≥3), and the per-PI-RADSv2 category prevalence of csPCa and false positives. RESULTS: Pathology after RP found 142 csPCas with median International Society of Urogenital Pathology grade group 2, and stage ≤pT2c in 68.6% of cases. CDR was comparable across the four MRI protocols (74.6% to 75.3% for R1, and 68.3% for R2). FDR was comparable as well (14.4%-14.5% for R1 and 11.1% for R2). sMRI was the minimum protocol equaling mpMRI in terms of CDR, although cesMRI, similarly to mpMRI, was associated with fewer PI-RADSv2 category 3 assignments and higher prevalence of csPCa within PI-RADSv2 category 3 observations (66.7% versus 76.9% for R1, and 100% versus 91.7% for R2, respectively). CONCLUSIONS: Among multiple abbreviated mpMRI-derived protocols, cesMRI was the one equaling mpMRI in terms of csPCa detection and minimizing PI-RADSv2 category 3 assignments.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Humanos , Masculino , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
3.
PLoS One ; 16(11): e0259724, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34752491

RESUMO

INTRODUCTION: Outcome predictions of patients with congenital diaphragmatic hernia (CDH) still have some limitations in the prenatal estimate of postnatal pulmonary hypertension (PH). We propose applying Machine Learning (ML), and Deep Learning (DL) approaches to fetuses and newborns with CDH to develop forecasting models in prenatal epoch, based on the integrated analysis of clinical data, to provide neonatal PH as the first outcome and, possibly: favorable response to fetal endoscopic tracheal occlusion (FETO), need for Extracorporeal Membrane Oxygenation (ECMO), survival to ECMO, and death. Moreover, we plan to produce a (semi)automatic fetus lung segmentation system in Magnetic Resonance Imaging (MRI), which will be useful during project implementation but will also be an important tool itself to standardize lung volume measures for CDH fetuses. METHODS AND ANALYTICS: Patients with isolated CDH from singleton pregnancies will be enrolled, whose prenatal checks were performed at the Fetal Surgery Unit of the Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico (Milan, Italy) from the 30th week of gestation. A retrospective data collection of clinical and radiological variables from newborns' and mothers' clinical records will be performed for eligible patients born between 01/01/2012 and 31/12/2020. The native sequences from fetal magnetic resonance imaging (MRI) will be collected. Data from different sources will be integrated and analyzed using ML and DL, and forecasting algorithms will be developed for each outcome. Methods of data augmentation and dimensionality reduction (feature selection and extraction) will be employed to increase sample size and avoid overfitting. A software system for automatic fetal lung volume segmentation in MRI based on the DL 3D U-NET approach will also be developed. ETHICS AND DISSEMINATION: This retrospective study received approval from the local ethics committee (Milan Area 2, Italy). The development of predictive models in CDH outcomes will provide a key contribution in disease prediction, early targeted interventions, and personalized management, with an overall improvement in care quality, resource allocation, healthcare, and family savings. Our findings will be validated in a future prospective multicenter cohort study. REGISTRATION: The study was registered at ClinicalTrials.gov with the identifier NCT04609163.


Assuntos
Hérnias Diafragmáticas Congênitas , Estudos de Coortes , Feminino , Humanos , Hipertensão Pulmonar , Recém-Nascido , Gravidez , Estudos Retrospectivos
4.
Br J Radiol ; 94(1127): 20210707, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34432542

RESUMO

OBJECTIVE: To investigate the impact of contrast-enhanced ultrasound (CEUS) in reclassifying incidental renal findings categorized as indeterminate lesions (IL) or Bosniak ≥ 2F complex renal cysts (CRC) on CT or MRI. METHODS: We retrospectively included 44 subjects who underwent CEUS between 2016 and 2019 to assess 48 IL (n = 12) and CRC (n = 36) incidentally found on CT or MRI. CEUS was performed by one radiologist with 10 year of experience with a sulfur hexafluoride-filled microbubble contrast agent. The same radiologist, blinded to clinical information and previous CT/MRIs, retrospectively reviewed CEUS images/videos, categorizing renal findings with Bosniak-derived imaging categories ranging from 0 (indeterminate) to 5 (solid lesion). CEUS-related reclassification rate was calculated (proportion of IL reclassified with an imaging category >0, or CRC reclassified below or above imaging category >2F). Using histological examination or a ≥ 24 months follow-up as the standard of reference, we also estimated per-lesion sensitivity/specificity for malignancy. RESULTS: CEUS reclassified 24/48 findings (50.0%; 95% C.I. 35.2-64.7), including 12/12 IL (100%; 95% CI 73.5-100) and 12/36 CRC (33.3%; 95% C.I. 18.5-50.9), mostly above category >2F (66.7%). CEUS and CT/MRI showed 96.0% (95%CI 79.7-99.9) vs 44.0% (95%CI 24.4-65.1) sensitivity, and 82.6% (95%CI 61.2-95.1) vs 60.9% (95%CI 38.5-80.3%) specificity. CONCLUSION: CEUS provided substantial and accurate reclassification of CT/MRI incidental findings. ADVANCES IN KNOWLEDGE: Previous studies included Bosniak 2 incidental findings, thus possibly underestimating CEUS-induced reclassification rates. Using a more meaningful cut-off (Bosniak ≥2F), problem-solving CEUS was effective as well, with higher reclassification rates for CRC than in literature.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Doenças Renais Císticas/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
5.
Radiol Med ; 126(4): 577-584, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33389557

RESUMO

PURPOSE: To investigate the inter-reader agreement in assessing high-resolution computed tomography (HRCT) features of coronavirus disease 2019 (COVID-19) pneumonia. METHOD: Seventy-seven consecutive patients (mean age, 64 ± 15 years) with mild COVID-19 pneumonia that underwent HRCT were retrospectively included. Three radiologists [two devoted to thoracic imaging (R1, R2), and one generalist (R3)] on a per-examination basis independently assessed ground-glass opacity (GGO), consolidation, and crazy-paving pattern. The extent of each feature (total feature score, TFS) was semi-quantitatively assessed, and each TFS summed up to obtain total lung score (TLS). Presence of organizing pneumonia (OP) pattern was also recorded. The inter-reader agreement was calculated with Cohen's Kappa (k) and Free-Marginal Multirater k. Multivariable analysis was run to determine whether imaging features were predictive of short-term evolution to severe disease (need for ventilation). RESULTS: Most features showed substantial inter-reader agreement, including TLS > 6 (k = 0.69), which was an independent predictor of short-term occurrence of severe disease, regardless of the reader (OR 9-53.19). Consolidation TFS > 2 and OP pattern showed substantial and moderate agreement, respectively, only when comparing R1 and R2. Consolidation TFS > 2 and OP pattern were independent predictors of severe disease for R2 (OR 4.87) and R1 (OR 6), respectively. CONCLUSIONS: The inter-reader agreement for most HRCT features of COVID-19 pneumonia ranges moderate-to-substantial, though it depends on readers' experience in the case of consolidation and OP pattern.


Assuntos
COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X/métodos
6.
Abdom Radiol (NY) ; 46(1): 84-95, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31925494

RESUMO

Contrast-enhanced ultrasound (CEUS) is gaining ever-increasing acceptance in the preoperative and postoperative evaluation of liver-transplanted patients. While indications are still a matter of research, CEUS is used in tertiary centers to supplement ultrasound (US) and Color Doppler US examination, with the potential of providing a comprehensive first-line ultrasound-based diagnosis. Alternatively, CEUS is used as a problem-solving tool when previous cross-sectional or US imaging was inconclusive, especially in assessing hepatocellular carcinoma, parenchymal perfusion abnormalities, the vascular status, and even the biliary tree. This review describes the potential use for CEUS in the setting of orthotopic liver transplantation (OLT).


Assuntos
Neoplasias Hepáticas , Transplante de Fígado , Meios de Contraste , Estudos Transversais , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Ultrassonografia
7.
Acta Radiol ; 62(7): 949-958, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32718179

RESUMO

BACKGROUND: Abbreviated magnetic resonance imaging (aMRI) protocols have emerged as an alternative to multiparametric MRI (mpMRI) to reduce examination time and costs. PURPOSE: To compare multiple aMRI protocols for predicting pathological stage ≥T3 (≥pT3) prostate cancer (PCa). MATERIAL AND METHODS: One hundred and eight men undergoing staging mpMRI before radical prostatectomy (RP) were retrospectively evaluated. 3.0-T imaging was performed with a 32-channel surface coil and a protocol including diffusion-weighted imaging (DWI), transverse T2-weighted (tT2W) imaging, coronal T2W (cT2W) imaging, sagittal T2W (sT2) imaging, and dynamic contrast-enhanced (DCE) imaging. Two readers independently assessed whether any MRI observation showed stage ≥T3 on each sequence (reading order: DWI, cT2W, tT2W, sT2W, DCE). Final stage was assessed by matching readers' assignments to pathology, and combining them into eight protocols: DWI + tT2W, DWI + cT2W + tT2W, DWI + tT2W + sT2W, DWI + cT2W + tT2W + sT2W, DWI + tT2W + DCE, DWI + cT2W + tT2W + DCE, DWI + tT2W + sT2W + DCE, and mpMRI. Diagnostic accuracy and inter-reader agreement for aMRI protocols were calculated. RESULTS: Prevalence of ≥pT3 PCa was 31.5%. Sensitivity, specificity, positive (PPV) and negative predictive value (NPV) of aMRI protocols were comparable to mpMRI for R1. Sensitivity was 74.3% (95% confidence interval [CI] 64.8-72.0) to 77.1% (95% CI 67.9-84.4), and NPV 86.8% (95% CI 78.6-92.3) to 88.1% (95% CI 80.1-93.3). All accuracy measures of the various aMRI protocols were similar to mpMRI also for R2, albeit all slightly lower compared to R1. On a per-protocol basis, there was substantial inter-reader agreement in predicting stage ≥pT3 (k 0.63-0.67). CONCLUSION: When comparing the diagnostic accuracy of multiple aMRI protocols against mpMRI for predicting stage ≥pT3 PCa, the protocol with the fewest sequences (DWI + tT2W) is apparently equivalent to standard mpMRI.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Protocolos Clínicos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prostatectomia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos
8.
World J Radiol ; 12(8): 156-171, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32913562

RESUMO

Kidney transplantation (KT) is an effective treatment for end-stage renal disease. Despite their rate has reduced over time, post-transplant complications still represent a major clinical problem because of the associated risk of graft failure and loss. Thus, post-KT complications should be diagnosed and treated promptly. Imaging plays a pivotal role in this setting. Grayscale ultrasound (US) with color Doppler analysis is the first-line imaging modality for assessing complications, although many findings lack specificity. When performed by experienced operators, contrast-enhanced US (CEUS) has been advocated as a safe and fast tool to improve the accuracy of US. Also, when performing CEUS there is potentially no need for further imaging, such as contrast-enhanced computed tomography or magnetic resonance imaging, which are often contraindicated in recipients with impaired renal function. This technique is also portable to patients' bedside, thus having the potential of maximizing the cost-effectiveness of the whole diagnostic process. Finally, the use of blood-pool contrast agents allows translating information on graft microvasculature into time-intensity curves, and in turn quantitative perfusion indexes. Quantitative analysis is under evaluation as a tool to diagnose rejection or other causes of graft dysfunction. In this paper, we review and illustrate the indications to CEUS in the post-KT setting, as well as the main CEUS findings that can help establishing the diagnosis and planning the most adequate treatment.

9.
J Magn Reson Imaging ; 50(5): 1604-1613, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30957321

RESUMO

BACKGROUND: It is unclear whether clinical models including the Partin tables (PT), the Memorial Sloan Kettering Cancer Center nomogram (MSKCCn), and the cancer of the prostate risk assessment (CAPRA) can benefit from incorporating multiparametric magnetic resonance imaging (mpMRI) when staging prostate cancer (PCa). PURPOSE: To compare the accuracy of clinical models, mpMRI, and mpMRI plus clinical models in predicting stage ≥pT3 of PCa. STUDY TYPE: Prospective monocentric cohort study. POPULATION: Seventy-three patients who underwent radical prostatectomy between 2016-2018. FIELD STRENGTH/SEQUENCE: 3.0T using turbo spin echo (TSE) imaging, single-shot echoplanar diffusion-weighted imaging, and T1 -weighted high-resolution-isotropic-volume-examination (THRIVE) contrast-enhanced imaging. ASSESSMENT: We calculated the probability of extraprostatic extension (EPE) using the PT and MSKCC, as well as the CAPRA score. Three readers with 2-8 years of experience in mpMRI independently staged PCa on imaging. STATISTICAL TESTS: Receiver operating characteristics analysis and logistic regression analysis to investigate the per-patient accuracy of mpMRI vs. clinical models vs. mpMRI plus clinical models in predicting stage ≥pT3. The alpha level was 0.05. RESULTS: Median probability for EPE and MSKCCn was 27.3% and 47.0%, respectively. Median CAPRA score was 3. Stage ≥pT3 occurred in 32.9% of patients. Areas under the curve (AUCs) were 0.62 for PT, 0.62 for MSKCCn, 0.64 for CAPRA, and 0.73-0.75 for mpMRI (readers 1-3) (P > 0.05 for all comparisons). Compared with mpMRI, the combination of mpMRI with PT or MSKCCn provided lower AUCs (P > 0.05 for all the readers), while the combination with CAPRA provided significantly higher (P < 0.05) AUCs in the case of readers 1 and 3. On multivariable analysis, mpMRI by reader 1 was the only independent predictor of stage ≥pT3 (odds ratio 7.40). DATA CONCLUSION: mpMRI was more accurate than clinical models and mpMRI plus clinical models in predicting stage ≥pT3, except for the combination of mpMRI and CAPRA in two out of three readers. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1604-1613.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Prostatectomia , Neoplasias da Próstata/cirurgia , Idoso , Algoritmos , Meios de Contraste , Imagem Ecoplanar/métodos , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Nomogramas , Probabilidade , Estudos Prospectivos , Neoplasias da Próstata/patologia , Curva ROC , Análise de Regressão , Reprodutibilidade dos Testes
10.
J Magn Reson Imaging ; 49(2): 546-555, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30187600

RESUMO

BACKGROUND: Most studies assessing interreader agreement of Prostate Imaging Reporting and Data System v. 2 (PI-RADS v2) have used biopsy as the standard of reference, thus carrying the risk of not definitively noting all existent cancers. PURPOSE: To evaluate the interreader agreement in assessing prostate cancer (PCa) of PI-RADS v2, using whole-mount histology as the standard of reference. STUDY TYPE: Monocentric prospective cohort study. POPULATION: In all, 48 patients with biopsy-proven PCa referred for radical prostatectomy, undergoing staging multiparametric magnetic resonance imaging (mpMRI) between May 2016 to February 2017. FIELD STRENGTH/SEQUENCE: 3.0T system using high-resolution T2 -weighted imaging, diffusion-weighted imaging (echo-planar imaging with maximum b-value 2000 sec/mm2 ), and dynamic contrast-enhanced imaging (T1 -weighted high resolution isotropic volume examination; THRIVE) ASSESSMENT: Three radiologists blinded to final histology (2-8 years of experience) analyzed mpMRI images independently, scoring imaging findings in accordance with PI-RADS v2. On a per-lesion basis, we calculated overall and pairwise interreader agreement in assigning PI-RADS categories, as well as assessing malignancy with categories ≥3 or ≥4, and stage ≥pT3. STATISTICAL TESTS: Cohen's kappa analysis of agreement. RESULTS: On 71 lesions found on histology, there was moderate agreement in assigning PI-RADS categories to all cancers (k = 0.53) and clinically significant cancers (csPCa) (k = 0.47). Assessing csPCa with PI-RADS ≥4 cutoff provided higher agreement than PI-RADS ≥3 cutoff (k = 0.63 vs. 0.57). Interreader agreement was higher between more experienced readers, with the most experienced one achieving the highest cancer detection rate (0.73 for csPCa using category ≥4). There was substantial agreement in assessing stage ≥pT3 (k = 0.72). DATA CONCLUSION: We found moderate to substantial agreement in assigning the PI-RADS v2 categories and assessing the spectrum of cancers found on whole-mount histology, with category 4 as the most reproducible cutoff for csPCa. Readers' experience influenced interreader agreement and cancer detection rate. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:546-555.


Assuntos
Biópsia/métodos , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Próstata/patologia , Prostatectomia , Radiologia/métodos , Radiologia/normas , Padrões de Referência , Reprodutibilidade dos Testes , Glândulas Seminais/patologia
11.
Radiol Case Rep ; 13(4): 890-894, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29997718

RESUMO

Transplant renal artery stenosis (TRAS) is a vascular complication occurring during the first 2 years after kidney transplantation, with an incidence and a prevalence ranging from 1% to 23%, and from 1.5% to 4%, respectively. Detection of TRAS is the key, since most stenoses may progress to renal graft loss, however it may be difficult to detect due to its nonspecific clinical manifestations. Although Doppler ultrasound has become a primary imaging technique, digital subtraction angiography (DSA) remains the gold standard for diagnosing TRAS. We present a case of delayed graft function following kidney transplantation complicated by a lateral by-pass with prosthesis upstream and downstream of renal anastomosis, TRAS criteria were unclear using Doppler ultrasound, contrast-enhanced computed tomography-scan, and DSA. Only contrast-enhanced ultrasound (CE-US), observing a delayed and pulsating contest impregnation of renal parenchyma, supported the hypothesis of TRAS that was confirmed by the measurement of trans-anastomosis pressure gradient during DSA.

12.
Eur J Radiol ; 93: 295-307, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28545872

RESUMO

Liver transplantation (LT) is the treatment of choice for end-stage chronic liver disease, fulminant liver failure and early stage hepatocellular carcinoma. As discussed in this review, state-of-the-art imaging modalities including ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI) play a pivotal role in the selection of patients and donors, as well as in early detection of those complications at risk of impairing graft function and/or survival. We also illustrate main imaging findings related to the wide spectrum of clinical problems raised by LT.


Assuntos
Transplante de Fígado/métodos , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Doença Hepática Terminal/patologia , Doença Hepática Terminal/cirurgia , Feminino , Veias Hepáticas/anatomia & histologia , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Doadores Vivos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Veia Porta/anatomia & histologia , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/patologia , Cuidados Pré-Operatórios/métodos , Tomografia Computadorizada por Raios X/métodos , Sítio Doador de Transplante/patologia , Transplantados , Transplantes/irrigação sanguínea , Ultrassonografia , Doenças Vasculares/patologia
13.
Front Oncol ; 4: 294, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25408923

RESUMO

Multi-parametric magnetic resonance imaging is an emerging imaging modality for diagnosis, staging, characterization, and treatment planning of prostate cancer. In this report, we reviewed the literature for studies assessing the accuracy of multi-parametric magnetic resonance imaging in detecting clinically significant prostate cancer, and we critically examined the future role of this imaging tool in various clinical diagnostic settings. There is accumulating evidence suggesting a high accuracy of multi-parametric magnetic resonance imaging in ruling out clinically significant disease. Although definition for clinically significant disease widely varies, the negative predictive value is very high at up to 98%. Multi-parametric magnetic resonance imaging should, thus, be further evaluated for application in different clinical scenarios in which it is desirable to reduce the proportion of unnecessary prostate biopsies and to limit the detection of indolent disease, such as opportunistic screening, persistent prostate cancer suspicion in men with previous negative prostate biopsies, and eligibility for active surveillance. Continued improvement in standardization of technical parameters, functional sequences, and image reporting systems is a pre-requisite for a rapid and successful dissemination of this imaging modality.

14.
World J Gastroenterol ; 20(20): 6180-200, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24876739

RESUMO

Orthotopic liver transplantation (OLT) represents a major treatment for end-stage chronic liver disease, as well as selected cases of hepatocellular carcinoma and acute liver failure. The ever-increasing development of imaging modalities significantly contributed, over the last decades, to the management of recipients both in the pre-operative and post-operative period, thus impacting on graft and patients survival. When properly used, imaging modalities such as ultrasound, multidetector computed tomography, magnetic resonance imaging (MRI) and procedures of direct cholangiography are capable to provide rapid and reliable recognition and treatment of vascular and biliary complications occurring after OLT. Less defined is the role for imaging in assessing primary graft dysfunction (including rejection) or chronic allograft disease after OLT, e.g., hepatitis C virus (HCV) recurrence. This paper: (1) describes specific characteristic of the above imaging modalities and the rationale for their use in clinical practice; (2) illustrates main imaging findings related to post-OLT complications in adult patients; and (3) reviews future perspectives emerging in the surveillance of recipients with HCV recurrence, with special emphasis on MRI.


Assuntos
Transplante de Fígado , Fígado/patologia , Colangiografia , Constrição Patológica , Artéria Hepática/patologia , Veias Hepáticas/patologia , Hepatite C/complicações , Humanos , Falência Hepática Aguda/cirurgia , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Tomografia Computadorizada Multidetectores , Recidiva Local de Neoplasia/cirurgia , Veia Porta/patologia , Período Pós-Operatório , Recidiva , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia , Trombose Venosa/patologia
15.
Comput Math Methods Med ; 2014: 587976, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24587815

RESUMO

PURPOSE: To quantify the impact of diagnostic confidence on radiological diagnosis with a fuzzy logic-based method. MATERIALS AND METHODS: Twenty-two oncologic patients with 20 cysts and 30 metastases ≤1 cm in size found at 64-row computed tomography were included. Two readers (R1/R2) expressed diagnoses as a subjective level of confidence P(d) in malignancy within the interval [0,1] rather than on a "crisp" basis (malignant/benign); confidence in benignancy was 1 - p(d). When cross-tabulating data according to the standard of reference, 2 × 2 table cells resulted from the aggregation between p(d)/1 - p(d) and final diagnosis. We then assessed (i) readers diagnostic performance on a fuzzy and crisp basis; (ii) the "divergence" δ(F, C) (%) as a measure of how confidence impacted on crisp diagnosis. RESULTS: Diagnoses expressed with lower confidence increased fuzzy false positives compared to crisp ones (from 0 to 0.2 for R1; from 1 to 2.4 for R2). Crisp/fuzzy accuracy was 94.0%/93.6% (R1) and 94.0/91.6% (R2). δ(F, C) (%) was larger in the case of the less experienced reader (R2) (up to +7.95% for specificity). According to simulations, δ(F, C) (%) was negative/positive depending on the level of confidence in incorrect diagnoses. CONCLUSION: Fuzzy evaluation shows a measurable effect of uncertainty on radiological diagnoses.


Assuntos
Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Algoritmos , Diagnóstico por Computador/métodos , Feminino , Lógica Fuzzy , Humanos , Fígado/patologia , Masculino , Informática Médica , Pessoa de Meia-Idade , Metástase Neoplásica , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
16.
Clin Imaging ; 38(2): 136-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24332555

RESUMO

We investigated whether diffusion-weighted Imaging (DWI) adds diagnostic confidence in assessing focal liver lesions (FLLs). By reviewing FLLs without and with DWI at 1.5 T, two radiologists scored the confidence in diagnosing benignancy/malignancy (confidence score), and DWI usefulness (usefulness score). We showed that adding DWI significantly decreased the confidence score of the most experienced radiologist and increased his confidence in false-negative diagnoses showing atypical features on conventional magnetic resonance imaging.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Hepáticas/diagnóstico , Fígado/patologia , Adulto , Idoso , Tomada de Decisões , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
17.
Radiol Med ; 119(4): 240-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24297584

RESUMO

PURPOSE: This study was done to assess the feasibility of three-dimensional ultrasonography (3D-US) for volume calculation of solid breast lesions. MATERIALS AND METHODS: The volumes of 36 malignant lesions were measured using conventional 2D-US, 3D-US and magnetic resonance imaging (MRI) and compared with that obtained with histology (standard of reference). With 2D Ultrasouns, volume was estimated by measuring three diameters and calculating volume with the mathematical formula for spheres. With 3D-US, stored images were retrieved and boundaries of masses were manually outlined; volume calculation was performed with VOCAL software. For MRI, volume measurements were obtained with special software for 3D reconstructions, after each lesion had been manually outlined. Histology measured the three main diameters and the volume was estimated using the mathematical formula for spheres. Interclass correlation coefficient (ICC) and Bland-Altman plots were used to assess agreement between the volumes measured. RESULTS: ICC indicated that a good level of concordance was identified between 3D-US and histology (0.79). According to the Bland-Altman analysis, limits of agreement of mean differences of the volumes measured with the three imaging modalities were comparable with histology: -2 ÷ 1.5 cm(3) for 3D-US; -2.3 ÷ 1.3 cm(3) for 2D-US and -2.2 ÷ 1.6 cm(3) for MRI. CONCLUSIONS: 3D-US is a reliable method for the volumetric assessment of breast lesions. 3D-US is able to provide valuable information for the preoperative evaluation of lesions.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imageamento Tridimensional , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Neoplasias da Mama/patologia , Estudos de Viabilidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Gradação de Tumores
18.
J Affect Disord ; 146(3): 390-4, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23084182

RESUMO

BACKGROUND: The hypothalamus is a brain structure involved in the neuroendocrine aspect of stress and anxiety. Evidence suggests that generalized anxiety disorder (GAD) and panic disorder (PD) might be accompanied by dysfunction of the hypothalamus-pituitary-adrenal axis (HPA), but so far structural alterations were not studied. We investigated hypothalamic volumes in patients with either GAD or PD and in healthy controls. METHODS: Twelve GAD patients, 11 PD patients and 21 healthy controls underwent a 1.5T MRI scan. Hypothalamus volumes were manually traced by a rater blind to subjects' identity. General linear model for repeated measures (GLM-RM) was used to compare groups on hypothalamic volumes, controlling for total intracranial volume, age and sex. RESULTS: The hypothalamus volume was significantly reduced (p=0.04) in GAD patients, with significant reductions in both the left (p=0.02) and right side (p=0.04). Patients with PD did not differ significantly (p=0.73). Anxiety scores were inversely correlated with hypothalamic volumes. LIMITATIONS: The small sample size could reduce the generalizability of the results while the lack of stress hormone measurements renders functional assessment of the hypothalamus-pituitary-adrenal axis not feasible. CONCLUSIONS: The present study showed decreased hypothalamic volumes in GAD patients but not in those with PD. Future longitudinal studies should combine volumetric data with measurements of stress hormones to better elucidate the role of the HPA axis in GAD.


Assuntos
Transtornos de Ansiedade/patologia , Hipotálamo/anatomia & histologia , Transtorno de Pânico/patologia , Adulto , Transtornos de Ansiedade/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Transtorno de Pânico/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Adulto Jovem
19.
J Magn Reson Imaging ; 36(4): 943-50, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22649035

RESUMO

PURPOSE: To investigate the negative predictive value (NPV) for malignancy of 3.0 Tesla (T) MRI in patients with "gray zone" PSA level and prior negative biopsies. MATERIALS AND METHODS: We enrolled 26 patients with PSA level between 2.5 and 10 ng/mL and no cancer at previous biopsies. Examinations were performed on a 3.0T system using T2-weighted imaging, diffusion-weighted imaging, spectroscopy, and postcontrast dynamic study. A regional scheme was used to record MRI findings and to perform subsequent transrectal-ultrasonography-guided biopsy. Based on the matching between imaging and biopsy findings we estimated MRI predictive values, sensitivity, specificity and accuracy on a per-patient and per-region basis. RESULTS: On a per patient basis, MRI had five true-positive (5/26; 19.2%), eight true-negative (8/26; 30.8%) and no false-negative cases, corresponding to a NPV and sensitivity of 100% each. Thirteen patients were assessed as false-positive cases (13/26; 50.0%) (specificity of 38.1%). Five of them (5/26; 19.2%) showed high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small-acinar proliferation (ASAP) at biopsy. T2-weighted imaging alone showed per-region NPV (96.8%). CONCLUSION: Because of the high NPV, MRI had the potential to avoid unnecessary biopsy in approximately one-third of "gray-zone" patients with a negative examination. Additionally, MRI was useful to address to biopsy more than one-third of patients with cancer or high-risk lesions as HGPIN and ASAP.


Assuntos
Biomarcadores Tumorais/sangue , Imageamento por Ressonância Magnética/métodos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Idoso , Biópsia , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Abdom Imaging ; 36(2): 196-205, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20473669

RESUMO

PURPOSE: To estimate the prevalence of incidental pancreatic cysts (IPCs) in asymptomatic patients addressed to magnetic resonance cholangiopancreatography (MRCP), and to correlate it with clinical and imaging features. MATERIALS AND METHODS: Magnetic resonance cholangiopancreatography performed over 26-months on 152 patients with unsuspected/unknown pancreatic disease were reviewed to assess IPCs' features of presentation. Multivariate analysis was performed to evaluate the correlation of IPCs with clinical information and type of pancreaticobiliary findings at MRCP. RESULTS: Prevalence of IPCs was 44.7%. Cysts sized 3-24 mm (mean, 6.08 mm), and were ≤4 in number in 83.8% of patients. Based on number, dimensions and relation with the main pancreatic duct, IPCs presented with intraductal-papillary-mucinous neoplasm (IPMN)-like or indeterminate patterns in 31.7% and 13.1% of patients, respectively. At follow-up on 24 patients, no evolution was found, except in one patient with proven IPMN showing increase in cysts number and dimensions (evolution rate of 4.1%). Features correlating with IPCs were age ≥60 years old, and history of autoimmune hepatobiliary disease, showing odds ratios of 5.95 (95% CI 2.77-12.79) and 0.13 (95% CI 0.04-0.44), respectively. CONCLUSIONS: Incidental pancreatic cysts represent a frequent finding at MRCP, correlating positively with increasing age, and negatively with biliary autoimmune disease. Cysts more frequently present with IPMN-like pattern.


Assuntos
Colangiopancreatografia por Ressonância Magnética , Imageamento Tridimensional , Cisto Pancreático/diagnóstico , Fatores Etários , Idoso , Distribuição de Qui-Quadrado , Colangiopancreatografia por Ressonância Magnética/métodos , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Achados Incidentais , Modelos Logísticos , Masculino , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Cisto Pancreático/epidemiologia , Prevalência , Estatísticas não Paramétricas
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