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1.
Eur J Radiol ; 166: 111015, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37541183

RESUMO

OBJECTIVE: To systematically review the efficacy of radiomics models derived from computed tomography (CT) or magnetic resonance imaging (MRI) in preoperative prediction of the histopathological grade of hepatocellular carcinoma (HCC). METHODS: Systematic literature search was performed at databases of PubMed, Web of Science, Embase, and Cochrane Library up to 30 December 2022. Studies that developed a radiomics model using preoperative CT/MRI for predicting the histopathological grade of HCC were regarded as eligible. A pre-defined table was used to extract the data related to study and patient characteristics, characteristics of radiomics modelling workflow, and the model performance metrics. Radiomics quality score and the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) were applied for research quality evaluation. RESULTS: Eleven eligible studies were included in this review, consisting of 2245 patients (range 53-494, median 165). No studies were prospectively designed and only two studies had an external test cohort. Half of the studies (five) used CT images and the other half MRI. The median number of extracted radiomics features was 328 (range: 40-1688), which was reduced to 11 (range: 1-50) after feature selection. The commonly used classifiers were logistic regression and support vector machine (both 4/11). When evaluated on the two external test cohorts, the area under the curve of the radiomics models was 0.70 and 0.77. The median radiomics quality score was 10 (range 2-13), corresponding to 28% (range 6-36%) of the full scale. Most studies showed an unclear risk of bias as evaluated by QUADAS-2. CONCLUSION: Radiomics models based on preoperative CT or MRI have the potential to be used as an imaging biomarker for prediction of HCC histopathological grade. However, improved research and reporting quality is required to ensure sufficient reliability and reproducibility prior to implementation into clinical practice.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Reprodutibilidade dos Testes , Meios de Contraste , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
2.
Br J Radiol ; 95(1139): 20220370, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113499

RESUMO

OBJECTIVES: To compare the dynamic changes in future liver remnant (FLR) function and volume after hepatectomy and to evaluate the associations between three modalities in assessment of liver function. METHODS: Liver function and volume were quantified pre-operatively, at post-operative day (POD) 7 and POD 28 in 10 patients with colorectal liver metastases undergoing hemihepatectomy using the indocyanine green retention (ICG) test, hepatobiliary scintigraphy (HBS) and gadoxetic acid-enhanced MRI. The 99mTc mebrofenin uptake rate in the FLR was applied as a reference of liver function. MRI-derived parameters including liver-to-muscle ratio (LMR), liver-to-spleen ratio (LSR) and hepatocellular uptake index (HUI) were used for liver function assessment. Spearman's correlation analysis was used to evaluate the associations. RESULTS: Increase in liver function ranged from 13 to 152% (median 92%) and in volume from 37 to 134% (median 79%). There was no significant discrepancy in increase between FLR function and volume during the first month following hepatectomy. LMR showed a significant correlation to ICG test (r = -0.66, p < 0.05) while LSR had an association with standardized FLR function obtained by HBS (r = -0.71, p < 0.05). During the first week after hepatectomy, pre-operative HUI and LMR showed the strongest correlation to the FLR growth in function and volume respectively (p < 0.05). CONCLUSION: The observed growth in FLR volume is closely related to the functional increase within 1 month after hepatectomy. Gadoxetic acid-enhanced MRI might substitute HBS for regional liver function assessment and provide an imaging tool for liver growth prediction. ADVANCES IN KNOWLEDGE: Liver function growth was parallel with liver volume increase during the perioperative period. Liver function assessment with gadoxetic acid-enhanced MRI was comparable with that of HBS indicating that gadoxetic acid-enhanced MRI could substitute HBS for regional liver function evaluation.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Hepatectomia , Verde de Indocianina , Testes de Função Hepática , Cintilografia , Fígado/diagnóstico por imagem , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/cirurgia
3.
Br J Radiol ; 95(1133): 20211094, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35195445

RESUMO

OBJECTIVES: We examined the longitudinal and cross-sectional relationship between automated MRI-analysis and single-slice axial CT imaging for determining muscle size and muscle fat infiltration (MFI) of the anterior thigh. METHODS: Twenty-two patients completing sex-hormone treatment expected to result in muscle hypertrophy (n = 12) and atrophy (n = 10) underwent MRI scans using 2-point Dixon fat/water-separated sequences and CT scans using a system operating at 120 kV and a fixed flux of 100 mA. At baseline and 12 months after, automated volumetric MRI analysis of the anterior thigh was performed bilaterally, and fat-free muscle volume and MFI were computed. In addition, cross-sectional area (CSA) and radiological attenuation (RA) (as a marker of fat infiltration) were calculated from single slice axial CT-images using threshold-assisted planimetry. Linear regression models were used to convert units. RESULTS: There was a strong correlation between MRI-derived fat-free muscle volume and CT-derived CSA (R = 0.91), and between MRI-derived MFI and CT-derived RA (R = -0.81). The 95% limits of agreement were ±0.32 L for muscle volume and ±1.3% units for %MFI. The longitudinal change in muscle size and MFI was comparable across imaging modalities. CONCLUSIONS: Both automated MRI and single-slice CT-imaging can be used to reliably quantify anterior thigh muscle size and MFI. ADVANCES IN KNOWLEDGE: This is the first study examining the intermodal agreement between automated MRI analysis and CT-image assessment of muscle size and MFI in the anterior thigh muscles. Our results support that both CT- and MRI-derived measures of muscle size and MFI can be used in clinical settings.


Assuntos
Imageamento por Ressonância Magnética , Coxa da Perna , Tecido Adiposo/diagnóstico por imagem , Adulto , Humanos , Extremidade Inferior , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Coxa da Perna/diagnóstico por imagem , Tomografia Computadorizada por Raios X
4.
Cancers (Basel) ; 13(22)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34831018

RESUMO

Preoperative prediction of microvascular invasion (MVI) is of importance in hepatocellular carcinoma (HCC) patient treatment management. Plenty of radiomics models for MVI prediction have been proposed. This study aimed to elucidate the role of radiomics models in the prediction of MVI and to evaluate their methodological quality. The methodological quality was assessed by the Radiomics Quality Score (RQS), and the risk of bias was evaluated by the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). Twenty-two studies using CT, MRI, or PET/CT for MVI prediction were included. All were retrospective studies, and only two had an external validation cohort. The AUC values of the prediction models ranged from 0.69 to 0.94 in the test cohort. Substantial methodological heterogeneity existed, and the methodological quality was low, with an average RQS score of 10 (28% of the total). Most studies demonstrated a low or unclear risk of bias in the domains of QUADAS-2. In conclusion, a radiomics model could be an accurate and effective tool for MVI prediction in HCC patients, although the methodological quality has so far been insufficient. Future prospective studies with an external validation cohort in accordance with a standardized radiomics workflow are expected to supply a reliable model that translates into clinical utilization.

5.
Phys Med ; 61: 58-63, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31151580

RESUMO

OBJECTIVE: To investigate if the conventional localizer radiograph (LR) can be replaced by a synthetic LR (SLR), generated from a low-dose spiral CT scan, for CT scan planning with minimal changes to current clinical workflows. METHODS: A dosimetric comparison of SLRs and LRs was made using Monte Carlo methods. Water equivalent diameters (WEDs) of a centered and mis-centered phantom were estimated from low-dose spiral CT scans and LRs acquired at different angles. Body sizes, in the form of two lengths and two diameters obtained from SLRs and LRs, were compared for 10 patients (4 men and 6 women with a mean age of 74.8 and 76.2 years respectively) undergoing CT of thorax and abdomen. The image quality of SLRs for CT scan planning relative to LRs was rated using a 5-grade scale by four radiologists and two CT radiographers. RESULTS: An SLR can be obtained at a comparable effective dose to that of traditionally acquired LRs: 0.14 mSv. WEDs from LRs were more affected by mis-centering than WEDs calculated from low-dose spiral scans. One significant discrepancy of estimated body sizes was observed, the broadest part of the patient that on lateral localizers showed a mean deviation of 17.7 mm (range: 7.3-28.7 mm, p < 0.001). The anteroposterior/posteroanterior SLR image quality was assessed as better compared to an LR while the same could not be shown for lateral localizers. CONCLUSIONS: SLRs based on low-dose spiral scans can replace LRs for CT planning.


Assuntos
Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Método de Monte Carlo , Doses de Radiação , Radiometria , Tomografia Computadorizada por Raios X/instrumentação
6.
BMC Med Imaging ; 19(1): 17, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30767773

RESUMO

BACKGROUND: The clinical and research value of Computed Tomography (CT) volumetry of esophageal cancer tumor size remains controversial. Development in CT technique and image analysis has made CT volumetry less cumbersome and it has gained renewed attention. The aim of this study was to assess esophageal tumor volume by semi-automatic measurements as compared to manual. METHODS: A total of 23 esophageal cancer patients (median age 65, range 51-71), undergoing CT in the portal-venous phase for tumor staging, were retrospectively included between 2007 and 2012. One radiology resident and one consultant radiologist measured the tumor volume by semiautomatic segmentation and manual segmentation. Reproducibility of the respective measurements was assessed by intraclass correlation coefficients (ICC) and by average deviation from mean. RESULTS: Mean tumor volume was 46 ml (range 5-137 ml) using manual segmentation and 42 ml (range 3-111 ml) using semiautomatic segmentation. Semiautomatic measurement provided better inter-observer agreement than traditional manual segmentation. The ICC was significantly higher for semiautomatic segmentation in comparison to manual segmentation (0.86, 0.56, p < 0.01). The average absolute percentage difference from mean was reduced from 24 to 14% (p < 0.001) when using semiautomatic segmentation. CONCLUSIONS: Semiautomatic analysis outperforms manual analysis for assessment of esophageal tumor volume, improving reproducibility.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
7.
Nutrition ; 61: 93-98, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30703575

RESUMO

OBJECTIVES: The aim of this study was to perform intermethod comparisons between the following three measures of muscle mass depletion in patients eligible for liver transplantation: 1) fat-free mass index (FFMI) measured by dual-energy x-ray absorptiometry (DXA), 2) appendicular skeletal muscle mass index (ASMI) measured by DXA, and 3) skeletal muscle index (SMI) measured at the third lumbar level by computed tomography (CT). METHODS: The medical records of patients who received liver transplants between 2009 and 2012 at Karolinska University Hospital were retrospectively reviewed. Adult patients with a chronic liver disease who had both DXA and CT scans performed within a 30-d period during their pretransplant workup were included. RESULTS: Appendicular skeletal muscle mass index measured by DXA (ASMIDXA) and skeletal mass index measured by computed tomography (SMICT) provide similar results when assessing the presence of muscle mass depletion in patients with chronic liver diseases and FFMIDXA can be falsely high in patients with ascites. Both ASMIDXA and SMICT thus appear to be useful methods in the pretransplant evaluation of muscle mass depletion both for patients with and without ascites. CONCLUSIONS: ASMI measured with DXA is a useful alternative method to SMI measured with CT when a CT scan is not clinically indicated or available.


Assuntos
Absorciometria de Fóton/estatística & dados numéricos , Hepatopatias/complicações , Músculo Esquelético/diagnóstico por imagem , Atrofia Muscular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Idoso , Composição Corporal , Índice de Massa Corporal , Doença Crônica , Feminino , Humanos , Hepatopatias/cirurgia , Transplante de Fígado , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/etiologia , Período Pré-Operatório , Reprodutibilidade dos Testes , Estudos Retrospectivos
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