Gadoxetic acid-enhanced MRI for hepatocellular carcinoma and hypointense nodule observed in the hepatobiliary phase.

PURPOSE: The aim of our study was to evaluate the diagnostic accuracy of gadoxetic acid-enhanced magnetic resonance (MR) imaging both in the detection of hepatocellular carcinoma (HCC) and precancerous lesions and in the assessment of their evolution. MATERIALS AND METHODS: A retrospective study was undertaken on 56 patients with chronic liver disease and suspected liver lesions. We evaluated the number, size and signal intensity of the nodules on dynamic and hepatobiliary MR images. Follow-up studies were carried out every 3 months. Statistical analysis was performed using the Fisher's exact test. RESULTS: A total of 120 nodules were identified in 41 patients. Of these, 92/120 nodules (76.6%; mean diameter 18.4 mm) showed the typical HCC vascular pattern: 90/92 nodules appeared hypointense and 2/92 were hyperintense on hepatobiliary phase images. An additional 28/120 hypointense, nonhypervascular nodules (23.3%; mean diameter 11 mm) were detected on hepatobiliary phase images, 15 of which showed hypointensity also on the equilibrium phase images. During the 3- to 12-month follow-up, 14/28 nodules (mean diameter 13.3 mm) developed the typical vascular pattern of HCC. CONCLUSIONS: Gadoxetic acid-enhanced MR imaging is useful for detecting HCC as well as hypovascular nodules with potential progression to HCC. Lesions measuring more than 10 mm in diameter are at higher risk of developing into HCC (p = 0.0128).

Pneumatosis cystoides intestinalis: case report and review of literature.

Pneumatosis intestinalis is the presence of gas in the bowel wall and is divided into two categories: life-threatening pneumatosis intestinalis and benign pneumatosis intestinalis. Pneumatosis cystoides intestinalis is a rare condition characterized by gas-filled cysts in submucosa and subserosa. The pathogenesis is unclear, although some causes have been theorized. The presenting clinical findings may be very heterogeneous. Intestinal pneumatosis may lead to various complications. Distinguishing between pneumatosis cystoides intestinalis and life-threatening pneumatosis intestinalis may be challenging, although computed tomography scan allows the detection of additional findings that may suggest an underlying, potentially worrisome cause of pneumatosis intestinalis. To correctly manage the patients affected with this disease is important to differentiate the two types of pneumatosis. The patients with pneumatosis cystoides intestinalis are usually treated conservatively; the surgical treatment is reserved for complications. We described a case of a patient with pneumatosis cystoides intestinalis and gastric perforation. The medical history of the patient revealed a breast cancer treated with mastectomy and chemotherapy; the patient did not report a history of gastrointestinal disease. The abdomen CT showed abscess formation at the level of the antro-pylorus, linear pneumatosis in the gastric wall, and free abdominal air. Multiple small air bubbles was observed in intestinal wall. The intestinal wall was not thickened with normal contrast mucosal enhancement. CT examination showed neither mesenteric stranding nor portal venous gas embolism. The findings of the surgery were gastric perforated peptic ulcer and benign pneumatosis intestinalis.

Non-Hypervascular Hypointense Nodules at Gadoxetic Acid MRI: Hepatocellular Carcinoma Risk Assessment with Emphasis on the Role of Diffusion-Weighted Imaging.

INTRODUCTION AND AIM: In cirrhotic patients, the characterization of hypovascular nodules, hypointense on hepatobiliary phase gadoxetic acid disodium-enhanced magnetic resonance images (Gd-EOB-DTPA-enhanced MRI), is essential to look for the proper approach strategy. Our objective was to evaluate the imaging features and risk assessment of hypovascular nodules, hypointense on Gd-EOB-DTPA-enhanced MRI, focusing on the diagnostic value of diffusion-weighted imaging (DWI). MATERIAL AND METHODS: This prospective study includes 35 patients with 50 hypovascular hypointense nodules. Signal intensity on T2-weighted images and DWI, vascular pattern on dynamic contrast-enhanced MRI and on hepatobiliary phase, and volume doubling time were analyzed for each nodule as well as patient's clinical features. Univariate and multivariate analyses were made to determine the variables associated with the development of hypervascular pattern. RESULTS: On 24 months follow-up period, 40% of the hypointense nodules (mean size 14 mm ± 6.1) became hypervascular hepatocellular carcinoma (HCC) with 6 and 12 months cumulative risk of 45 and 55%. Nine/12 (75%, mean size 15.50 mm ± 7.2) that appeared hyperintense in DWI at first exam show malignant transformation (p value = 0.007). Univariate and multivariate analyses identified hyperintensity at initial DWI (OR 6.49; 95% CI 1.28-32.80; p value = 0.009) and size ≥10 mm (OR 6.22; 95% CI 1.57-24.63; p value = 0.024) as independent factors with the development of HCC. CONCLUSION: In conclusion, hypovascular lesions ≥10 mm and those hyperintense in DWI were associated with progression to hypervascular HCC. A close follow-up or histological characterization is recommended to improve patients outcome and to develop effective treatment.

The prevalence of pancreatic cystic lesions in patients with liver cirrhosis is double that in controls.

BACKGROUND AND AIMS: Pancreatic cystic lesions (PCLs) are commonly diagnosed incidentally and are often preneoplastic. Their presence may influence the management of patients with chronic diseases such as liver cirrhosis (LC). This study evaluated the prevalence and nature of PCLs in LC patients. METHODS: The images of 192 LC patients and 192 controls who underwent either computed tomography scan or nuclear magnetic resonance were reviewed for the presence and nature of PCLs. The prevalence of PCLs in both groups and differences between LC patients with and without PCLs were analysed. Multiple logistic regression analysis was used to investigate factors associated with PCLs. RESULTS: Thirty-five of 192 LC patients (18%) and 19/192 controls (10%) had PCLs (p = .027). The prevalence of presumptive intraductal pancreatic mucinous neoplasm (IPMN) was double in LC patients compared with controls (14% vs 7%; p = .065). In multivariate analysis, age, LC and having undergone a magnetic resonance cholangiopancreatography were factors associated with PCLs and IPMNs. LC patients with PCLs were older at the time of imaging and had a longer history of liver disease (67 vs. 43 months; p = 0.039) compared with LC patients without PCLs. CONCLUSIONS: PCLs are more common in LC patients than in controls, and most are IPMNs. The occurrence of PCLs in LC patients seems to be related to age and disease duration.

Magnetic resonance enterography in Crohn's disease: new simple proposal to assess disease activity.

PURPOSE: The aim is to determine the accuracy of magnetic resonance enterography (MRE) in evaluating Crohn's disease (CD) activity. MATERIALS AND METHODS: Seventy-seven patients with CD underwent MRE. The primary analysis was to determine associations between MRE findings, Harvey-Bradshaw Index, and C-reactive protein (CRP), then we have created a new MRE score that it was also correlated with clinical and laboratory data. RESULTS: MRE score for CD significantly correlates with CRP (P=.003). Significant associations were found between degree of contrast enhancement and CRP (P=.002) and between comb sign and CRP (P=.001). CONCLUSIONS: These results make MRE an important instrument for evaluation of CD activity.

Value of diffusion-weighted MRI and apparent diffusion coefficient measurements for predicting the response of locally advanced rectal cancer to neoadjuvant chemoradiotherapy.

PURPOSE: The aim of our study was to assess the performance value of magnetic resonance imaging (MRI) in the restaging of locally advanced rectal cancer after neoadjuvant chemoradiotherapy (CRT) and in the identification of good vs. poor responders to neoadjuvant therapy. MATERIALS AND METHODS: A total of 34 patients with locally advanced rectal cancer underwent MRI prior to and after CRT. T stage and tumor regression grade (TRG) on post-CRT MRI was compared with the pathological staging ypT and TRG. Tumor volume and the apparent diffusion coefficient (ADC) were measured using diffusion-weighted imaging (DWI) before and after neoadjuvant CRT; the percentage of tumor volume reduction and the change of ADC (ΔADC) was also calculated. ADC parameters and the percentage of tumor volume reduction were correlated to histopathological results. The diagnostic performance of ADC and volume reduction to assess tumor response was evaluated by calculating the area under the ROC curve and the optimal cut-off values. RESULTS: A significant correlation between the T stage and the TRG defined in DW-MRI after CRT and the ypT and the TRG observed on the surgical specimens was found (p = 0.001; p < 0.001). The mean post-CRT ADC and ΔADC in responder patients was significantly higher compared to non-responder ones (p = 0.001; p = 0.01). Furthermore, the mean post-CRT ADC values were significantly higher in tumors with T-downstage (p = 0.01). CONCLUSION: DW-MRI may have a significant role in the restaging and in the evaluation of post-CRT response of locally advanced rectal cancer. Quantitative analysis of DWI through ADC map may result in a promising noninvasive tool to evaluate the response to therapy.

Comparison of diffusion-weighted imaging and gadoxetic acid-enhanced MR images in the evaluation of hepatocellular carcinoma and hypovascular hepatocellular nodules.

PURPOSE: To compare diffusion-weighted imaging (DWI) and gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) magnetic resonance imaging (MRI) in the evaluation of hepatocellular carcinoma (HCC) and nodules at high risk of HCC transformation. MATERIALS AND METHODS: We evaluated nodules' size, vascular pattern, and signal intensity on hepatobiliary phase images and on DWI of 105 nodules (41 cirrhotic patients). RESULTS: A total of 35/66 HCCs identified on Gd-EOB-DTPA MRI showed hyperintensity on DWI. A total of 25/39 nodules (hypovascular and hypointense nodule on hepatobiliary phase images) progressed to HCC (higher risk for nodules ≥10mm in size and hyperintense on DWI, P<.05). CONCLUSION: Gd-EOB-DTPA MRI demonstrated a significant role in the identification of nodule at higher risk of HCC transformation, and hyperintensity on DWI was associated with progression to HCC.

Magnetic resonance cholangiopancreatography with secretin stimulation in the diagnosis of intraductal papillary mucinous neoplasm: a paradigmatic case report.

Context. One of the characteristic findings of intraductal papillary mucinous neoplasms (IPMN) is the presence of a direct communication between the lesion and the ductal pancreatic system and when magnetic resonance cholangiopancreatography (MRCP) shows uncertain findings, it is useful to perform a MRCP after secretin stimulation (MRCP-S) which provides a better visualization of the ductal system. Case Report. We present a case of 51-year-old man in whom, during a CT follow-up for a renal tumour, was found a cystic lesion of the pancreas. To better evaluate the lesion and its suspected communication with the pancreatic system, MR with gadolinium and MRCP and MRCP-S were performed. With the MRCP and MRI it was not possible to identify a clear communication between the cystic lesion and the ductal system. MRCP-S showed an increase in signal intensity of the lesion and its communication with the ductal system, allowing us to classify the cystic lesion as a main duct in intraductal papillary mucinous neoplasm. The patient underwent a surgical duodenal pancreatectomy. The histological result of the specimen confirmed the diagnosis of adenocarcinoma IPMN. Conclusion. In this case MRCP-S has allowed a clearer identification of the cystic lesion allowing a correct diagnosis and treatment.