OA-GAN: organ-aware generative adversarial network for synthesizing contrast-enhanced medical images.

Contrast-enhanced computed tomography (CE-CT) images are vital for clinical diagnosis of focal liver lesions (FLLs). However, the use of CE-CT images imposes a significant burden on patients due to the injection of contrast agents and extended shooting. Deep learning-based image synthesis models offer a promising solution that synthesizes CE-CT images from non-contrasted CT (NC-CT) images. Unlike natural images, medical image synthesis requires a specific focus on certain organs or localized regions to ensure accurate diagnosis. Determining how to effectively emphasize target organs poses a challenging issue in medical image synthesis. To solve this challenge, we present a novel CE-CT image synthesis model called, Organ-Aware Generative Adversarial Network (OA-GAN). The OA-GAN comprises an organ-aware (OA) network and a dual decoder-based generator. First, the OA network learns the most discriminative spatial features about the target organ (i.e. liver) by utilizing the ground truth organ mask as localization cues. Subsequently, NC-CT image and captured feature are fed into the dual decoder-based generator, which employs a local and global decoder network to simultaneously synthesize the organ and entire CECT image. Moreover, the semantic information extracted from the local decoder is transferred to the global decoder to facilitate better reconstruction of the organ in entire CE-CT image. The qualitative and quantitative evaluation on a CE-CT dataset demonstrates that the OA-GAN outperforms state-of-the-art approaches for synthesizing two types of CE-CT images such as arterial phase and portal venous phase. Additionally, subjective evaluations by expert radiologists and a deep learning-based FLLs classification also affirm that CE-CT images synthesized from the OA-GAN exhibit a remarkable resemblance to real CE-CT images.

Imaging manifestations of head and neck lymphatic malformations: A single-center experience of 170 surgical cases.

OBJECTIVES: To discuss the imaging manifestations and the utility of preoperative ultrasonography (US), contrast-enhanced computed tomography (CE-CT) and contrast enhanced magnetic resonance imaging (CE-MRI) in diagnosing the pediatric head and neck lymphatic malformations (HNLMs). METHODS: We performed a retrospective review of 170 children who were referred to our hospital in the past 9 years for the treatment of HNLMs. RESULTS: The diagnostic rates of US, CE-CT and CE-MRI were 93.0% (146/157), 94.7% (143/151) and 100% (45/45), respectively. As in multilocular cases, intracystic septa detection rate was 91.5% (130/142), 50.4% (68/135) and 88.1% (37/42), and which had a statistical difference (χ2 = 25.8131, p < 0.05). US showed capsule contents anechoic in 51.0% (80/157) cases, hypoechoic or mixed echoic in 49.0% (77/157) cases, and flocculent or dotted echo floating in 36.9% (58/157) cases. CT showed low density of the capsule contents without enhancement in 69.5% (105/151) cases and mixed density with enhancement in 30.4% (46/151) cases. Liquid-liquid levers were seen in 8.6% (13/151) cases. MRI showed T1WI high signal and T2WI low signal of the capsule contents without enhancement in 28.9% (13/45) cases and mixed density in 71.1% (32/45) cases. Liquid-liquid levers were seen in 46.7% (21/45) cases. There were statistically significant differences between pure HNLMs and intracystic hemorrhage in capsule content (echo, density, signal), enhancement, and liquid-liquid lever (all p < 0.05). Among US, CE-CT and CE-MRI, intracystic hemorrhage diagnostic accuracy had a statistical difference (χ2 = 25.4152, p < 0.05). CONCLUSIONS: For clinical diagnosis and evaluation of HNLMs, we suggest that US combined with CE-CT for acute cases, and for stable cases, US combined with CE-MRI.

The Pattern of Metastatic Breast Cancer: A Prospective Head-to-Head Comparison of [18F]FDG-PET/CT and CE-CT.

The study aimed to compare the metastatic pattern of breast cancer and the intermodality proportion of agreement between [18F]FDG-PET/CT and CE-CT. Women with metastatic breast cancer (MBC) were enrolled prospectively and underwent a combined [18F]FDG-PET/CT and CE-CT scan to diagnose MBC. Experienced nuclear medicine and radiology physicians evaluated the scans blinded to the opposite scan results. Descriptive statistics were applied, and the intermodality proportion of agreement was used to compare [18F]FDG-PET/CT and CE-CT. In total, 76 women with verified MBC were enrolled in the study. The reported number of site-specific metastases for [18F]FDG-PET/CT vs. CE-CT was 53 (69.7%) vs. 44 (57.9%) for bone lesions, 31 (40.8%) vs. 43 (56.6%) for lung lesions, and 16 (21.1%) vs. 23 (30.3%) for liver lesions, respectively. The proportion of agreement between imaging modalities was 76.3% (95% CI 65.2-85.3) for bone lesions; 82.9% (95% CI 72.5-90.6) for liver lesions; 57.9% (95% CI 46.0-69.1) for lung lesions; and 59.2% (95% CI 47.3-70.4) for lymph nodes. In conclusion, bone and distant lymph node metastases were reported more often by [18F]FDG-PET/CT than CE-CT, while liver and lung metastases were reported more often by CE-CT than [18F]FDG-PET/CT. Agreement between scans was highest for bone and liver lesions and lowest for lymph node metastases.

Predictive Value of a Radiomics Nomogram Model Based on Contrast-Enhanced Computed Tomography for KIT Exon 9 Gene Mutation in Gastrointestinal Stromal Tumors.

OBJECTIVES: To establish and validate a radiomics nomogram model for preoperative prediction of KIT exon 9 mutation status in patients with gastrointestinal stromal tumors (GISTs). MATERIALS AND METHODS: Eighty-seven patients with pathologically confirmed GISTs were retrospectively enrolled in this study. Imaging and clinicopathological data were collected and randomly assigned to the training set (n = 60) and test set (n = 27) at a ratio of 7:3. Based on contrast-enhanced CT (CE-CT) arterial and venous phase images, the region of interest (ROI) of the tumors were manually drawn layer by layer, and the radiomics features were extracted. The intra-class correlation coefficient (ICC) was used to test the consistency between observers. Least absolute shrinkage and selection operator regression (LASSO) were used to further screen the features. The nomogram of integrated radiomics score (Rad-Score) and clinical risk factors (extra-gastric location and distant metastasis) was drawn on the basis of multivariate logistic regression. The area under the receiver operating characteristic (AUC) curve and decision curve analysis were used to evaluate the predictive efficiency of the nomogram, and the clinical benefits that the decision curve evaluation model may bring to patients. RESULTS: The selected radiomics features (arterial phase and venous phase features) were significantly correlated with the KIT exon 9 mutation status of GISTs. The AUC, sensitivity, specificity, and accuracy in the radiomics model were 0.863, 85.7%, 80.4%, and 85.0% for the training group (95% confidence interval [CI]: 0.750-0.938), and 0.883, 88.9%, 83.3%, and 81.5% for the test group (95% CI: 0.701-0.974), respectively. The AUC, sensitivity, specificity, and accuracy in the nomogram model were 0.902 (95% confidence interval [CI]: 0.798-0.964), 85.7%, 86.9%, and 91.7% for the training group, and 0.907 (95% CI: 0.732-0.984), 77.8%, 94.4%, and 88.9% for the test group, respectively. The decision curve showed the clinical application value of the radiomic nomogram. CONCLUSION: The radiomics nomogram model based on CE-CT can effectively predict the KIT exon 9 mutation status of GISTs and may be used for selective gene analysis in the future, which is of great significance for the accurate treatment of GISTs.

Breast Cancer Systemic Staging (Comparison of Computed Tomography, Bone Scan, and 18F-Fluorodeoxyglucose PET/Computed Tomography).

After an overview of the principles of bone scintigraphy, contrast-enhanced computed tomography (CE-CT) and 18F-fluorodeoxyglucose (FDG)-PET/CT, the advantages and limits of these modalities in the staging of breast cancer are discussed in this paper. CT and PET/CT are not optimal for delineating primary tumor volume, and PET is less efficient than the sentinel node biopsy to depict small axillary lymph node metastases. In large breast cancer tumor, FDG PET/CT is useful to show extra-axillary lymph nodes. FDG PET/CT is superior to bone scan and CE-CT in detecting distant metastases, and it results in a change of treatment plan in nearly 15% of patients.

Response Monitoring in Metastatic Breast Cancer: A Prospective Study Comparing 18F-FDG PET/CT with Conventional CT.

This study aimed to compare contrast-enhanced CT (CE-CT) and 18F-FDG PET/CT for response monitoring in metastatic breast cancer using the standardized response evaluation criteria RECIST 1.1 and PERCIST. The objective was to examine whether progressive disease was detected systematically earlier by one of the modalities. Methods: Women with biopsy-verified metastatic breast cancer were enrolled prospectively and monitored using combined CE-CT and 18F-FDG PET/CT every 9-12 wk to evaluate response to first-line treatment. CE-CT scans and RECIST 1.1 were used for clinical decision-making without accessing the 18F-FDG PET/CT scans. At study completion, 18F-FDG PET/CT scans were unmasked and assessed according to PERCIST. Visual assessment was used if response criteria could not be applied. The modality-specific time to progression was defined as the time from the baseline scan until the first scan demonstrating progression. Paired comparative analyses for CE-CT versus 18F-FDG PET/CT were applied, and the primary endpoint was earlier detection of progression by one modality. Secondary endpoints were time to detection of progression, response categorization, visualization of changes in response over time, and measurable disease according to RECIST and PERCIST. Results: In total, 87 women were evaluable, with a median of 6 (1-11) follow-up scans. Progression was detected first by 18F-FDG PET/CT in 43 (49.4%) of 87 patients and first by CE-CT in 1 (1.15%) of 87 patients (P < 0.0001). Excluding patients without progression (n = 32), progression was seen first on 18F-FDG PET/CT in 78.2% (43/55) of patients. The median time from detection of progression by 18F-FDG PET/CT to that of CE-CT was 6 mo (95% CI, 4.3-6.4 mo). At baseline, 76 (87.4%) of 87 patients had measurable disease according to PERCIST and 51 (58.6%) of 87 patients had measurable disease according to RECIST 1.1. Moreover, 18F-FDG PET/CT provided improved visualization of changes in response over time, as seen in the graphical abstract. Conclusion: Disease progression was detected earlier by 18F-FDG PET/CT than by CE-CT in most patients, with a potentially clinically relevant median 6-mo delay for CE-CT. More patients had measurable disease according to PERCIST than according to RECIST 1.1. The magnitude of the final benefit for patients is a perspective for future research.

The predictive potential of contrast-enhanced computed tomography based radiomics in the preoperative staging of cT4 gastric cancer.

Background: The accuracy of preoperative staging is crucial for cT4 stage gastric cancer patients. The aim of this study was to develop the radiomics model and evaluate its predictive potential for differentiating preoperative cT4 stage gastric cancer patients into pT4b and no-pT4b patients. Methods: A multicenter retrospective analysis of 704 gastric cancer patients with preoperative contrast-enhanced computed tomography (CE-CT) staging cT4 between January 2008 and December 2021. These patients were divided into the training cohort (478 patients, the Affiliated Hospital of Qingdao University) and validation cohort (226 patients, the Weihai Wendeng District People's Hospital). According to the pathological stage of the tumors, the patients were divided into pT4b or no-pT4b stage. In the training cohort, the clinical and radiomics features were analyzed to construct the clinical model, tri-phase radiomics signatures and nomogram. Two kinds of methods were employed to achieve dimensionality reduction: (I) the least absolute shrinkage and selection operator (LASSO); and (II) the minimum redundancy maximum relevance (mRMR) algorithms. We utilized Logistic regression, support vector machine (SVM), Decision tree and Adaptive boosted tree (AdaBoost) algorithms as the machine learning classifiers. The nomogram was constructed on the clinical characteristics and the Rad-score. The performance of the models was evaluated by receiver operating characteristic (ROC) area under the curve (AUC), Decision Curve Analysis (DCA) curve and calibration curve. Results: The 345 pT4b and 359 no-pT4b stage patients were included in this study. In the validation cohort, the AUC of the clinical model was 0.793 (95% CI: 0.732-0.855). The tri-phase radiomics features combined with the SVM algorithm was the best radiomics signature with an AUC of 0.862 (95% CI: 0.812-0.912). The nomogram was the best predictive model of all with an AUC of 0.893 (95% CI: 0.834-0.927). In the training and validation cohorts, the calibration curves and DCA curves of the nomogram showed satisfactory result. Conclusions: CE-CT-based radiomics nomogram offers good accuracy and stability in differentiating preoperative cT4 stage gastric cancer patients into pT4b and non-pT4b stages, which has a great clinical relevance for selecting the course of treatment for cT4 stage gastric cancer patients.

Small bowel carcinoid tumor causing intestinal ischemia: A case report with review of the literature.

Background: Intestinal carcinoid tumors are well-differentiated neuroendocrine tumors that are capable of secreting bioactive hormones and/or amines; These tumors are uncommon but are the most common primary tumors of the small intestine. Case presentation: We report the case of an 80-year-old woman who presented with a long history (about 14 years ago) of atypical digestive symptoms such as vague abdominal pain, alternating diarrhea, and constipation, treated as functional colopathy without improvement, until the day when she presented with worsening pain that prompted her consultation. CT scan revealed typical manifestations of a carcinoid tumor associated with signs of subacute small bowel ischemia. Despite the surgery being considered a gold standard treatment, it was rejected due to the extent of tumor mesenteric involvement, therefore, the patient received only somatostatin treatment. Conclusion: Small bowel carcinoid tumors are rare, with typical imaging features based on cross-sectional imaging (CE CT/MRI). Intestinal ischemia is a well-known complication that can be a factor in mortality.

"Honeycomb" appearance in large-duct type pancreatic ductal adenocarcinoma: Case report with radiologic-pathologic correlation.

Large-duct type pancreatic ductal adenocarcinoma (PDA) is a rare morphologic variant forming large duct elements. This case report, to our knowledge, is the first report of a large-duct type PDA with a "honeycomb" appearance resembling a serous cystic neoplasm (SCN) on CT and MRI. The patient is an 82-year-old woman who presented with upper abdominal pain. Dynamic contrast-enhanced CT revealed a multilocular cyst with honeycomb loculi, in which the cyst walls showed gradual enhancement. On T2-weighted MRI, the mass displayed inhomogeneous hyperintensity characterized by a honeycomb appearance with irregular and thick hypointense cyst walls. The patient underwent distal pancreatectomy; histopathological diagnosis was large-duct type PDA. Although the imaging features of large-duct type PDA may resemble those of SCN, this distinction between PDA and SCN is important because the treatment options are very different.

Metastatic choriocarcinoma with hemorrhagic complications and spontaneous ovarian hyperstimulation syndrome: A case report.

Gestational choriocarcinoma is a malignant trophoblastic tumor arising from any gestational event, even with a long latency period, generally in the reproductive female. It is associated with a high level of beta-human chorionic gonadotropin. Its primary site is usually the uterus but not all patients have a detectable lesion in this site. Regression of the primary tumor after it has metastasized is not uncommon, and one-third of cases manifest as complications of metastatic disease. In this report we present an uncommon case of gestational choriocarcinoma with lung, liver and jejunal metastases at the time of diagnosis without evidence of pelvic disease, in 34-year-old woman. The main points of interest of our case were the development of the ovarian hyperstimulation syndrome with massive multicystic ovarian enlargement induced by high level of beta-human chorionic gonadotropin and the bleeding of jejunal and liver metastases, due to the high vascularity of the tumor tissue, a condition known as "Choriocarcinoma Syndrome". We will focus on the radiological findings of metastases, bleeding complications and ovarian hyperstimulation syndrome.

A Comprehensive Computer-Assisted Diagnosis System for Early Assessment of Renal Cancer Tumors.

Renal cell carcinoma (RCC) is the most common and a highly aggressive type of malignant renal tumor. In this manuscript, we aim to identify and integrate the optimal discriminating morphological, textural, and functional features that best describe the malignancy status of a given renal tumor. The integrated discriminating features may lead to the development of a novel comprehensive renal cancer computer-assisted diagnosis (RC-CAD) system with the ability to discriminate between benign and malignant renal tumors and specify the malignancy subtypes for optimal medical management. Informed consent was obtained from a total of 140 biopsy-proven patients to participate in the study (male = 72 and female = 68, age range = 15 to 87 years). There were 70 patients who had RCC (40 clear cell RCC (ccRCC), 30 nonclear cell RCC (nccRCC)), while the other 70 had benign angiomyolipoma tumors. Contrast-enhanced computed tomography (CE-CT) images were acquired, and renal tumors were segmented for all patients to allow the extraction of discriminating imaging features. The RC-CAD system incorporates the following major steps: (i) applying a new parametric spherical harmonic technique to estimate the morphological features, (ii) modeling a novel angular invariant gray-level co-occurrence matrix to estimate the textural features, and (iii) constructing wash-in/wash-out slopes to estimate the functional features by quantifying enhancement variations across different CE-CT phases. These features were subsequently combined and processed using a two-stage multilayer perceptron artificial neural network (MLP-ANN) classifier to classify the renal tumor as benign or malignant and identify the malignancy subtype as well. Using the combined features and a leave-one-subject-out cross-validation approach, the developed RC-CAD system achieved a sensitivity of 95.3%±2.0%, a specificity of 99.9%±0.4%, and Dice similarity coefficient of 0.98±0.01 in differentiating malignant from benign tumors, as well as an overall accuracy of 89.6%±5.0% in discriminating ccRCC from nccRCC. The diagnostic abilities of the developed RC-CAD system were further validated using a randomly stratified 10-fold cross-validation approach. The obtained results using the proposed MLP-ANN classification model outperformed other machine learning classifiers (e.g., support vector machine, random forests, relational functional gradient boosting, etc.). Hence, integrating morphological, textural, and functional features enhances the diagnostic performance, making the proposal a reliable noninvasive diagnostic tool for renal tumors.

Heterotopic accessory spleen with squamous epithelial cyst in pancreas mimicking other pancreatic tumor: a case report.

A 49-year-old female undergoing a periodic health examination at other hospital revealed a mass in the tail of pancreas. The patient denied any personal history of surgery except subtotal hysterectomy because of multiple myomas in uterus 7 years ago, family history of abdominal cancer and trauma. Physical examination and laboratory finding (including tumor marker) were unremarkable. Chest X-ray result was normal. Contrast enhanced ultrasound (CEUS) examination showed a well-defined hypoechoic pancreatic mass which was suggestive of solid pseudopapillary tumor. Contrast enhanced computed tomography (CE-CT) of the abdomen revealed a mass of hypodensity suggestive of intraductal papillary mucinous neoplasm. Because of the risk of bleeding and exclusion of surgical contraindications, patient underwent laparoscopic surgery. Intraoperatively, a solid mass was identified in the tail of pancreas, the intraoperative frozen pathological examination suggested a heterotopic accessary spleen (HAS) with squamous epithelial cyst. Partial pancreatectomy was performed. The uniqueness of this case is that the spleen can be ectopic to the pancreas, what is even more unexpected is that the HAS undergone cystic change. When encountering a pancreatic mass, we need to think about the possibility of HAS. In conclusion, it is important to diagnose HAS with squamous cyst in the pancreatic tail presenting as other pancreatic masses.

FDG-PET/CT Versus Contrast-Enhanced CT for Response Evaluation in Metastatic Breast Cancer: A Systematic Review.

18F-fluorodeoxyglucose positron emission tomography with integrated computed tomography (FDG-PET/CT) and contrast-enhanced computed tomography (CT) can be used for response evaluation in metastatic breast cancer (MBC). In this study, we aimed to review literature comparing the PET Response Criteria in Solid Tumors (PERCIST) with Response Evaluation Criteria in Solid Tumors (RECIST) in patients with MBC. We made a systematic search in Embase, PubMed/Medline, and Cochrane Library using a modified PICO model. The population was MBC patients and the intervention was PERCIST or RECIST. Quality assessment was performed using the QUADAS-2 checklist. A total of 1975 articles were identified. After screening by title/abstract, 78 articles were selected for further analysis of which 2 duplicates and 33 abstracts/out of focus articles were excluded. The remaining 43 articles provided useful information, but only one met the inclusion and none of the exclusion criteria. This was a retrospective study of 65 patients with MBC showing one-year progression-free survival for responders versus non-responders to be 59% vs. 27% (p = 0.2) by RECIST compared to 64% vs. 0% (p = 0.0001) by PERCIST. This systematic literature review identified a lack of studies comparing the use of RECIST (with CE-CT) and PERCIST (with FDG-PET/CT) for response evaluation in metastatic breast cancer. The available sparse literature suggests that PERCIST might be more appropriate than RECIST for predicting prognosis in patients with MBC.

Strategy for the treatment of spontaneous isolated visceral artery dissection.

OBJECTIVES: To determine the incidence of rare spontaneous isolated visceral artery dissection (SIVAD), characterize its pathogenesis, and suggest treatment strategies. MATERIALS AND METHODS: We reviewed abdominal contrast-enhanced computed-tomography (CE-CT) scans from January 2005 to December 2016 retrospectively in our institution, identified 47 SIVAD patients and classified them into a symptomatic (n = 22) or asymptomatic group (n = 25). Further, we classified the five types based on the CE-CT images. Patient characteristics, incidence, vascular risk factors, complications, symptoms, treatments outcomes, and morphology features on CE-CT images were analyzed. RESULTS: SIVAD was seen on 0.09% of all abdominal CE-CT scans, and 0.68% of all abdominal CT-CT scans obtained for the evaluation of acute abdominal symptoms. The asymptomatic group had significantly fewer patients with periarterial fat stranding or branch vessel involvement on CE-CT images (p < 0.01). The mean length of the dissection was longer in the symptomatic group (p < 0.05). In the asymptomatic group, dissection-related abdominal symptoms and complications did not develop; followed-up CE-CT scans showed improvement in the dissection lesions in 1 (4.0%) patient, no changes in 22 (88.0%), and complete remodeling in 2 (8.0%). In the symptomatic group, one patient presented with organ ischemia at diagnosis and five patients developed organ ischemia underwent endovascular intervention. In the remaining 16 patients received nonoperative intervention only, followed-up CE-CT scans showed improvement in 13 (86.7%), and complete remodeling in 2 (13.3%). CONCLUSIONS: Symptomatic SIVAD patients should be hospitalized because some of those may experience organ ischemia or aneurysm formation. Endovascular intervention is a feasible treatment for complications of SIVAD.

Liver Function in Areas of Hepatic Venous Congestion After Hepatectomy for Liver Cancer: 99mTc-GSA SPECT/CT Fused Imaging Study.

Background/Aim: The sacrifice of a major hepatic vein can cause hepatic venous congestion (HVC). We evaluated the effects of HVC on regional liver function using the liver uptake value (LUV), that was calculated from 99m Tc-labeled-galactosyl-human-serum-albumin ( 99m Tc-GSA) single-photon emission computed tomography (SPECT) /contrast-enhanced computed tomography (CE-CT) fused images. Patients and Methods: Sixty-two patients underwent 99m Tc-GSA SPECT/CE-CT prior to hepatectomy for liver cancer and at 7 days after surgery were divided into groups with (n=8) and without HVC (n=54). In the HVC group, CT volume (CTv) and LUV were separately calculated in both congested and non-congested areas. Results: The remnant LUV/CTv of the HVC group was significantly smaller than that of the non-HVC group (p<0.01). The mean functional ratio was 0.47±0.05, and all ratios were ≥0.39. Conclusion: After hepatectomy with sacrifice of major hepatic vein, liver function per unit volume in the congested areas was approximately 40% of that in the non-congested areas.

Usefulness of positron emission tomography (PET)/contrast-enhanced computed tomography (CE-CT) in discriminating between malignant and benign intraductal papillary mucinous neoplasms (IPMNs).

BACKGROUND/OBJECTIVES: We evaluated the usefulness of positron emission tomography (PET)/contrast-enhanced computed tomography (CE-CT) in discriminating between malignant and benign intraductal papillary mucinous neoplasms (IPMNs). METHODS: PET/CE-CT imaging was conducted on 29 IPMN lesions, which subsequently underwent surgery. Preoperative findings on PET/CE-CT imaging were compared with the histological findings of the resected specimens to determine the diagnostic accuracy of PET/CE-CT imaging for evaluation of the differential diagnosis between benign and malignant IPMNs. RESULTS: The final diagnoses of the 29 IPMN lesions were 9 benign and 20 malignant. Overall, 18 of the 20 malignant cases were positive for FDG uptake, while 7 of 9 benign cases were negative. The sensitivity, specificity, and diagnostic accuracy for benign/malignant differentiation using FDG uptake as a marker were 90.0%, 77.8%, and 86.2%, respectively. When guideline-based high-risk findings were used as markers, sensitivity, specificity, and diagnostic accuracy for mural nodules were 50.0%, 66.7%, and 55.2%, while they were 40.0%, 56%, and 48.3% for main duct dilatation, respectively. CONCLUSIONS: FDG uptake on PET is a useful new marker for malignancy in benign/malignant differentiation. Because PET/CE-CT imaging is a noninvasive imaging modality that can evaluate FDG uptake in addition to the conventional high-risk findings, we believe it should be the first-line method for determining therapeutic approaches to IPMN.

Contrast-enhanced computed tomography plus gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging for gross classification of hepatocellular carcinoma.

Accurate gross classification through imaging is critical for determination of hepatocellular carcinoma (HCC) patient prognoses and treatment strategies. The present retrospective study evaluated the utility of contrast-enhanced computed tomography (CE-CT) combined with gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (EOB-MRI) for diagnosis and classification of HCCs prior to surgery. Ninety-four surgically resected HCC nodules were classified as simple nodular (SN), SN with extranodular growth (SN-EG), confluent multinodular (CMN), or infiltrative (IF) types. SN-EG, CMN and IF samples were grouped as non-SN. The abilities of the two imaging modalities to differentiate non-SN from SN HCCs were assessed using the EOB-MRI hepatobiliary phase and CE-CT arterial, portal, and equilibrium phases. Areas under the ROC curves for non-SN diagnoses were 0.765 (95% confidence interval [CI]: 0.666-0.846) for CE-CT, 0.877 (95% CI: 0.793-0.936) for EOB-MRI, and 0.908 (95% CI: 0.830-0.958) for CE-CT plus EOB-MRI. Sensitivities, specificities, and accuracies with respect to identification of non-SN tumors of all sizes were 71.4%, 81.6%, and 75.5% for CE-CT; 96.4%, 78.9%, and 89.3% for EOB-MRI; and 98.2%, 84.2%, and 92.5% for CE-CT plus EOB-MRI. These results show that CE-CT combined with EOB-MRI offers a more accurate imaging evaluation for HCC gross classification than either modality alone.

Comparison of foetal US and MRI in the characterisation of congenital lung anomalies.

OBJECTIVES: To compare the accuracy of prenatal ultrasonography (US) to magnetic resonance imaging (MRI) in the characterisation of congenital lung anomalies, and to assess their agreement with final diagnosis. To evaluate the influence of additional MRI information on therapeutic management. METHODS: 26 prenatal congenital lung anomalies detected consecutively between 2006 and 2012 were retrospectively evaluated. Lesions were initially observed at prenatal US and further investigated with MRI. Prenatal US and MRI imaging findings, and suggested diagnosis were compared with the final diagnosis, obtained from autopsies (4), pathological evaluation following surgical resection (15) and postnatal imaging studies (7). RESULTS: Postnatal diagnoses included 7 congenital pulmonary airway malformations, 8 complex lesions, 7 overinflations, 1 sequestration, 1 bronchogenic cyst, 1 blastoma and 1 bilateral lymphangioma. Suggested prenatal US and MRI diagnosis was correct in 34.6% and 46.2% of patients, respectively, mainly isolated lung lesions with typical imaging findings. Nonspecific imaging findings at US and MRI studies were observed in 38.4% of cases. In 42% of the operated anomalies, pathological dissection revealed the presence of complex anomalies. MRI changed the US diagnosis, but not the further management in 9.7% of the lesions. CONCLUSIONS: Prenatal US and MRI showed a high accuracy in the diagnosis of isolated congenital lung lesions with typical imaging findings. However, overall characterisation rates were low, because of both a high percentage of complex lesions and of lesions with nonspecific imaging findings. MRI was better than US in characterising complex lesions, but its additional information did not influence therapy decisions.