Contrast-enhanced Computed Tomography Magnetic Resonance Imaging Research Articles

The added value of MRI in distinguishing malignant and benign ampullary strictures: a multicenter retrospective study.

To investigate the added value of using contrast-enhanced magnetic resonance imaging (MRI) in conjunction with contrast-enhanced computed tomography (CT) for differentiating malignant and benign ampullary strictures. The present retrospective study included 90 patients with ampullary strictures who underwent preoperative contrast-enhanced CT and contrast-enhanced MRI at two tertiary institutions. The image sets (i.e., CT alone vs. combined CT and MRI) were evaluated by three abdominal radiologists, who used a five-point Likert scale to score their confidence for diagnosing malignancy in patients with ampullary strictures. Diagnostic accuracy was calculated using receiver-operating characteristic (ROC) curve analysis, sensitivity, specificity, and accuracy. Additionally, interobserver agreement regarding the scoring of potential malignancies of the ampullary strictures was assessed. The addition of contrast-enhanced MRI to contrast-enhanced CT showed a significant improvement in predicting malignant ampullary strictures in all three observers (p = 0.007, 0.001, and 0.002) using ROC curve analysis, and a significant improvement was observed in diagnostic sensitivity and accuracy for predicting malignancy (p = 0.016 and 0.029 for observer 1; p = 0.023 and 0.010 for observer 2; and p = 0.010 and 0.011 for observer 3). The interobserver agreement for the five-point scale in determining malignancies of the ampullary strictures was 0.86 for CT alone and 0.93 for the combined set of CT and MRI. The addition of contrast-enhanced MRI to CT provided added value for differentiating malignant from benign ampullary strictures.

Clinical significance of neuroendocrine tumors : Incidence, symptoms, diagnosis, stage, and prognostic factors and their influence on disease management

Neuroendocrine neoplasms (NEN) are heterogenous with an increasing incidence in recent years. Overview on incidence, symptoms, diagnostics, grading, imaging and prognostic determinants, including factors having an impact on therapeutic management. Review on current literature, including original articles, reviews, guidelines and expert opinions. NEN are mainly located in the gastrointestinal tract and their incidence has increased in recent years, mainly due to improved diagnostics, e.g., cross-sectional imaging. Clinical characteristics include hormone excess syndromes (carcinoid syndrome). Laboratory markers such as chromograninA are commonly used as part of routine diagnostics, followed by endoscopic and endosonographic procedures, which also allow biopsies to be obtained. Tumor spread can be determined by contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) or somatostatin receptor (SSRT)-PET/CT (positron emission tomography). Prognostic factors include Ki67 index, type, and grading. Resection with curative intent is the therapy of choice. In ametastasized setting, SSRT-directed treatment approaches are favored, while in dedifferentiated NEN, conventional chemotherapy is needed. Abroad diagnostic armamentarium can be offered to NEN patients and the improved diagnostic procedures have most likely caused araising incidence in recent years. Among others, prognostic factors are Ki67 and NEN subtypes; these clinical determinants also have an impact on patient management.

Compared with CT/MRI LI-RADS, whether CEUS LI-RADS is worth popularizing in diagnosis of hepatocellular carcinoma?-a direct head-to-head meta-analysis.

Until now, there has been no systematic review or meta-analysis of direct head-to-head studies that compare two liver imaging reporting and data system (LI-RADS) algorithms, contrast-enhanced ultrasound (CEUS) LI-RADS and contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) LI-RADS, for the diagnostic efficacy of hepatocellular carcinoma. The purpose of this study was to identify and head-to-head compare the diagnostic performance of both LI-RADS algorithms for hepatocellular carcinoma. We searched the PubMed, EMBASE, Web of Science, and Cochrane Library databases from the inception of each database to April 26, 2022, to find the comparative study of both LI-RADS algorithms for hepatocellular carcinoma at risk of patients who underwent both LI-RADS algorithms. Eligibility criteria included only studies published in English, full reports published, both retrospective and prospective studies. Liver histology or imaging follow-up results served as the reference standard. We analyzed the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and summary receiver operating characteristic curve to determine summary estimates. The Quality Assessment of Diagnostic Accuracy Studies was utilized to assess the methodological quality. In 5 included studies (831 patients, 877 lesions), the pooled sensitivity and pooled specificity of CEUS LR-5 were 0.79, 0.81, and 0.78, 0.79 in CT/MRI LR-5, respectively. The pooled sensitivity and pooled specificity of CEUS LR-4/5 were 0.86, 0.70, and 0.93, 0.59 in CT/MRI LR-4/5, respectively. There was no obvious difference between the two LI-RADS algorithms for hepatocellular carcinoma, and there was no significant statistical difference between two LR-M algorithms for non-hepatocellular carcinoma malignancies. The results of our analysis demonstrated that CEUS LI-RADS has satisfactory diagnostic performance similar to that of CT/MRI LI-RADS, which provides a theoretical basis for the popularization of CEUS LI-RADS for diagnosing HCC. This work was supported by Sichuan Science and Technology Program (No. 2020YFS0211). We registered this study on the international prospective register of systematic reviews (PROSPERO, CRD42022328107) before the search step.

Association between oncological outcomes of patients with colorectal liver metastasis and additional gadoxetic acid-enhanced magnetic resonance imaging.

Gadoxetic acid-enhanced magnetic resonance imaging (MRI) has shown to be superior to contrast-enhanced computed tomography (CT) in studies, there is no adequate data on its impact on overall survival and recurrence-free survival in patients with colorectal liver metastasis. Our objective was to study the benefit afforded by gadoxetic acid-enhanced MRI in patients with colorectal liver metastasis, especially in terms of overall survival and recurrence-free survival. Patients who underwent surgical treatment for colorectal liver metastasis between January 2003 and December 2018 were divided into groups depending on the pro-operative imaging carried out. Overall survival and recurrence-free survival were compared between both groups. Totally, 480 cases were included. Gadoxetic acid-enhanced MRI detected 220 new lesions in 123 cases. Presence of metastatic nodules was confirmed by gadoxetic acid-enhanced MRI in 33 of the 55 patients (60.0%) with indeterminate nodules on contrast-enhanced CT. Gadoxetic acid-enhanced MRI detected significantly more nodules than contrast-enhanced CT (932 vs. 673, respectively, P<0.001). There was no difference in the 5-year overall survival (P=0.390) or in the 3-month (85.1% vs. 86.7%, respectively, P=0.790), 6-month (78.0% vs. 81.7%, respectively, P=0.570), or 1-year (65.7% vs. 69.6%, respectively, P=0.446) recurrence-free survival in patients examined with contrast-enhanced CT or gadoxetic acid-enhanced MRI. Although gadoxetic acid-enhanced MRI is more sensitive than contrast-enhanced CT, its utilization does not significantly affect the recurrence-free survival of the patient.

One-lung ventilation for percutaneous thermal ablation of liver tumors in the hepatic dome

Purpose To investigate the feasibility, efficacy and safety of one-lung ventilation for percutaneous thermal ablation of liver tumors in the hepatic dome. Materials and methods From 5 January 2017 to 16 April 2019, 64 patients who underwent ultrasound-guided thermal ablation with a total of 75 liver malignant tumors located in the hepatic dome were enrolled in the present study. One-lung ventilation was employed to improve the acoustic window and protect the lung and diaphragm. If the one-lung ventilation was unsuccessful, artificial pleural effusion was added. The technical efficacy was confirmed by contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) 1 month later. After that, CT/MRI was performed every 3–6 months. Results Among the enrolled patients, the technical success rate of one lung ventilation was 92.2% (59/64). The visibility scores of tumors were improved significantly after one-lung ventilation compared to those before one-lung ventilation (p < .001). Finally, 78.6% (55/70) of the tumors achieved clinical success of one-lung ventilation to become clearly visible and underwent thermal ablation. Fourteen of the remaining 15 tumors achieved a satisfactory acoustic window after combination of artificial pleural effusion. One lesion remained inconspicuous and partly affected by pulmonary gas. The follow-up period was 8 months (3–30 months). The technical efficacy rate was confirmed to be 100% (75/75). During the follow-up period, local tumor progression occurred in 2 patients (2/75, 2.7%). Major complications occurred in two patients (2/64, 3.1%) receiving one-lung ventilation. Conclusions One-lung ventilation is a promising noninvasive method for the thermal ablation of hepatic dome tumors due to its efficacy and safety.

Value of dynamic contrast-enhanced CT combined with MRI in differential diagnosis of adrenal adenoma and metastatic tumor

Objective To investigate the clinical significance of dynamic contrast-enhanced computed tomography (CT) combined with magnetic resonance imaging (MRI) in differential diagnosis of adrenal adenoma and metastasis. Methods 120 patients with adrenal adenoma who were examined by enhanced MRI and enhanced CT before operation were collected. According to the pathological examination after operation, they were divided into adrenal adenoma group (86 cases) and adrenal metastasis group (34 cases). The difference of time-density curve between the two groups was compared, and the diagnostic criteria were evaluated by using receiver operating characteristic (ROC) curve. Results Dynamic CT and dynamic MRI were mainly type A, followed by type C, B, D and E. Dynamic CT and dynamic MRI were mainly type B, followed by type D/E, type A and type C. There were significant differences in type A, B, C, E dynamic CT and dynamic MRI between the two groups (P 0.05). The AZ value of adrenal adenomas ranged from 0.714 to 0.825 and that of adrenal metastasis ranged from 0.872 to 0.965 at 3-30 minutes delay. Conclusions Dynamic contrast-enhanced CT combined with MRI in patients with adrenal adenoma and metastasis has a time-density difference, 5min has high discriminant value in time lapse. Key words: Image enhancement; Tomography, X-ray computed; Magnetic resonance imaging; Adrenal gland neoplasms

A report of 478 cases of gallbladder adenomyomatosis from a single center

Introduction: Gallbladder adenomyomatosis (ADM) is a non-neoplastic, non-inflammatory disease. Herein, we retrospectively analyzed pathologically confirmed cases of 15 years in our center to investigate the diagnosis and treatment of ADM. Method: Data of patients who received cholecystectomy and were pathologically confirmed to have gallbladder adenomyomatosis were retrieved from the pathological database of Peking University Third Hospital from January 1, 2003 to December 31, 2017. The epidemiology, clinical manifestation, imaging examinations, surgical treatments and pathological features of these patients were analyzed retrospectively. Result: Of the 14,454 patients who underwent cholecystectomy, 478 were pathologically confirmed to have gallbladder adenomyomatosis, with a detection rate of 3.3%. There were 369 cases (77.2%) with symptoms, 279 cases (58.4%) with gallbladder stones, and 2 cases (0.4%) with common bile duct stones. The preoperative diagnostic rates of ultrasound, contrast-enhanced computed tomography(CT), magnetic resonance cholangiopancreatography(MRCP) or contrast-enhanced magnetic resonance imaging(MRI) were 25.4% (108/425), 40.6% (58/143) and 45.8%(148/323), respectively. The diagnostic rate of ultrasound combined contrast-enhanced CT, MRCP or contrast-enhanced MRI were 64.1% (50/78). Laparoscopic cholecystectomy (LC) was performed in 436 cases (91.2%), with 1 case of common bile duct exploration, 1 case of endoscopic sphincterotomy(EST) on common bile duct stone, and 1 case of hepatoduodenal ligament lymph node dissection. Open cholecystectomy was performed in 42 cases (8.8%). There were 58 cases (12.1%) with cholesterol polyps or cholesterol deposition, 12 cases (2.5%) with gallbladder adenoma, and 2 cases (0.4%) with gallbladder carcinoma. Pathologically, 287 cases were classified into fundal type (239 cases, 83.3%), segmental type (27 cases, 9.4%), and diffuse type (21 cases, 7.3%). Conclusion: Gallbladder adenomyomatosis is often accompanied with gallbladder stones. Ultrasound combined with contrast-enhanced CT, MRCP or contrast-enhanced MRI can improve the diagnostic rate. Currently LC is the main procedure for the treatment of adenomyomatosis of gallbladder.

Homogenously isoattenuating insulinoma on biphasic contrast-enhanced computed tomography: Little benefits of diffusion-weighted imaging for lesion detection.

The aim of the present study was to evaluate the diagnostic benefit of diffusion-weighted imaging (DWI) in the detection of homogenous isoattenuating insulinoma on biphasic contrast-enhanced computed tomography (CT) preoperatively and to determine which magnetic resonance (MR) sequences exhibited the best diagnostic performance. A total of 44 consecutive patients who underwent biphasic contrast-enhanced CT and conventional MR imaging (MRI), including DWI on a 3T scanner, were identified retrospectively. Apparent diffusion coefficient (ADC) values of insulinomas and the surrounding pancreatic parenchyma were compared using a Wilcoxon signed-rank test. Receiver operating characteristic analysis was used to compare the diagnostic accuracy of four randomized image sets [T2-weighted image (WI), axial T1WI, DWI and T2WI + DWI] for each reader. Axial T1-weighted MRI exhibited the highest relative sensitivity for each reader; DWI alone exhibited the lowest relative sensitivity and the lower inter-reader agreement. There was no significant difference in lesion detection between T2WI and T2WI + DWI image sets for each reader. The ADC values of the insulinoma were significantly lower compared with those of the surrounding parenchyma. In conclusion, DWI does not benefit the detection of homogenous isoattenuating insulinoma. Axial T1WI is the optimal pulse sequence. Quantitative assessment of the tumor ADC values may be a useful tool to characterize identified pancreatic neoplasms.

Laparoscopic Radiofrequency Ablation with Intraoperative Contrast-Enhanced Ultrasonography for T1bN0M0 Renal Tumors: Initial Functional and Oncologic Outcomes

To assess the functional and oncologic outcomes of laparoscopic radiofrequency ablation (RFA) with intraoperative contrast-enhanced ultrasonography in treatment of T1b renal tumors. We performed a retrospective review of 51 patients with unilateral T1b renal tumors who underwent laparoscopic RFA from January 2007 to April 2012 with a mean follow-up of 31.5 months. The tumors were laparoscopically dissected and ablated with cool-tip RFA system under the guidance of contrast-enhanced ultrasound. Routine follow-up included contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) and renal function tests. Mean diameter of the treated renal tumors was 5.1 cm (range 4.1-6.4 cm). Initial ablation success rate was 46/51 (90.2%). Of five incompletely ablated patients, four experienced up to two additional sessions of percutaneous RFA and achieved complete ablation. After at least 12 months contrast-enhanced CT/MRI follow-up after RFA, one patient experienced local tumor recurrence and another developed pulmonary and bone metastases. The 3-year disease-free survival in patients with biopsy-proven cancer was 85.7%. There was no significant difference between the estimated glomerular filtration rate (eGFR) pre- and post-RFA. Mean change in eGFR following RFA was -2.2 mL/minute. No patients required dialysis in the periprocedural period. Major complications (≥Grade 3) only developed in two (3.9%) cases. Our initial experience with this technique in T1b renal tumors was favorable with good renal function preservation and oncologic outcomes. It may be a good alternative to partial nephrectomy for selected T1b renal tumors.

Complications and clinical outcomes of microwave ablation for liver metastatic cholangiocarcinoma after bilioenteric anastomosis

To explore the complications and clinical outcome of liver metastatic cholangiocarcinoma after microwave ablation (MWA) in patients with a history of pancreatoduodenectomy or liver resection with bilioenteric anastomosis. Retrospective study was made on 10 lesions of intra-hepatic metastatic cholangiocarcinoma undergoing MWA (range: 1.5 - 3.6 cm, mean: 3.3 ± 1.3 cm) in 6 patients (5 males and 1 female) from February 2008 to October 2011. All had a history of surgical resection for primary neoplasm and bilioenteric anastomosis. Four cases had intrahepatic biliary dilatation pneumatosis. All lesions were completely ablated according to the results of contrast-enhanced ultrasound (CEUS) or contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) at Month 1 post-MWA. Liver abscess and fistula occurred in 5 ablation zones (5/10) of 4 patients. Three cases were satisfactorily cured with antibiotic dosing, catheter drainage and supportive care. One case died 13 days after MWA. The overall 1, 2, 3-year survival rates of were 64.8%, 21.6% and 21.0% respectively (median: 15.7 months). A high technical success rate of MWA is obtained in the treatment of intrahepatic metastatic cholangiocarcinoma with bilioenteric anastomosis. However, the incidence of abscess formation remains high due to a coexistence of multiple risk factors.

Contrast-enhanced 3D ultrasonography in minute hepatocellular carcinoma.

The study aimed to clarify whether contrast-enhanced (CE) three-dimensional (3D) ultrasonography (US) can depict characteristic hyperstain and washout patterns in minute nodules ≤10mm of hepatocellular carcinoma (minute HCC), and whether it serves as a potent diagnostic modality. CE 3D US was carried out to depict hyperstain and washout of a solitary nodule ≤10mm in patients with liver cirrhosis. When both patterns were depicted with success, CE computed tomography (CT) and CE magnetic resonance imaging (MRI) were also carried out as part of a comparative study, and then a histological specimen was obtained by needle biopsy. The final diagnosis was based on the histopathological findings and a follow-up on the growth of nodules. All 12 minute nodules exhibiting hyperstain and washout showed evidence of HCC when examined by CE 3D US. The CE CT and CE MRI examinations could depict both of these patterns, characteristic of HCC, in most of the nodules but rather less successfully than CE 3D US. CE 3D US can depict hyperstain and washout patterns in minute HCC and serves as a potent modality for diagnosis.