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.

Evaluation of the Relationships Between Computed Tomography Features, Pathological Findings, and Prognostic Risk Assessment in Gastrointestinal Stromal Tumors.

OBJECTIVES: The aim of this study was to correlate computed tomography (CT) findings with pathology in gastrointestinal stromal tumors (GISTs). METHODS: A retrospective evaluation of CT images of 44 patients with GISTs was performed. Computed tomography findings analyzed were location, size, margins, degree and pattern of contrast enhancement, angiogenesis, necrosis, signs of invasion, peritoneal effusion, peritoneal implants, surface ulceration, and calcifications.Associations between CT features and mitotic rate, Miettinen classes of risk, lesions size, and among CT features were investigated. χ Test and Fisher test were performed. RESULTS: Mitotic rate was associated with margins (P = 0.016) and with adjacent organ invasion (P = 0.043). Pattern of contrast enhancement (P = 0.002), angiogenesis (P = 0.006), necrosis (P = 0.006), invasion of adjacent organs (P = 0.011), and margins (P = 0.006) were associated with classes of risk. Several associations (P < 0.05) between lesion size and CT features and among all the investigated CT features were found. CONCLUSIONS: Computed tomography features could reflect GIST biology being associated with the mitotic rate and with classes of risk.

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.

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.

Accuracy of high-resolution MRI with lumen distention in rectal cancer staging and circumferential margin involvement prediction.

OBJECTIVE: To evaluate the accuracy of magnetic resonance imaging (MRI) with lumen distention for rectal cancer staging and circumferential resection margin (CRM) involvement prediction. MATERIALS AND METHODS: Seventy-three patients with primary rectal cancer underwent high-resolution MRI with a phased-array coil performed using 60-80 mL room air rectal distention, 1-3 weeks before surgery. MRI results were compared to postoperative histopathological findings. The overall MRI T staging accuracy was calculated. CRM involvement prediction and the N staging, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were assessed for each T stage. The agreement between MRI and histological results was assessed using weighted-kappa statistics. RESULTS: The overall MRI accuracy for T staging was 93.6% (k = 0.85). The accuracy, sensitivity, specificity, PPV and NPV for each T stage were as follows: 91.8%, 86.2%, 95.5%, 92.6% and 91.3% for the group ≤ T2; 90.4%, 94.6%, 86.1%, 87.5% and 94% for T3; 98,6%, 85.7%, 100%, 100% and 98.5% for T4, respectively. The predictive CRM accuracy was 94.5% (k = 0.86); the sensitivity, specificity, PPV and NPV were 89.5%, 96.3%, 89.5%, and 96.3% respectively. The N staging accuracy was 68.49% (k = 0.4). CONCLUSION: MRI performed with rectal lumen distention has proved to be an effective technique both for rectal cancer staging and involved CRM predicting.

Percutaneous vertebroplasty for pain management in patients with multiple myeloma: is radiofrequency ablation necessary?

PURPOSE: This study was designed to investigate the added role of radiofrequency ablation (RFA) to vertebroplasty on the pain management of patients with multiple myeloma (MM). METHODS: Thirty-six patients (51-82 years) with vertebral localization of MM were randomly divided into two groups: 18 patients (group A) who underwent RFA and then vertebroplasty, and 18 patients (group B) who underwent only vertebroplasty. Primary endpoints were technical success and pain relief score rate measured by the visual analogue pain scores (VAS) and Roland-Morris Questionnaire (RMQ); secondary endpoint was the amount of administered analgesia. Survival and complications were compared. RESULTS: Technical success was 100 % in both groups. The VAS score (at 24 h and 6 weeks postprocedure) decreased in equal manner for both groups from a mean of 9.1-3.4 and 2.0 for group A and from a mean of 9.3-3.0 and 2.3 for group B; RMQ mean score was 19.8 for group A and 19.9 for group B and decreased to a mean of 9.6 and 8.2 for group A and 9.5 and 8.7 for group B. The amount of medication was equally decreased in the two groups. No statistically significant difference was noted. No major complication occurred and two patients died from other causes. CONCLUSIONS: The use of percutaneous vertebroplasty alone appears to be effective for the pain management of the patients with vertebral involvement of multiple myeloma. The use of RFA that includes cost and time does not offer any clear added benefit on the midterm pain management of such patients.

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).

Reconstruction of the superior vena cava by biologic conduit: assessment of long-term patency by magnetic resonance imaging.

BACKGROUND: To assess the long-term patency of the biologic prosthetic conduit used for reconstruction of the superior vena cava (SVC) by magnetic resonance imaging (MRI). METHODS: Patients undergoing oncologic resection and reconstruction of the SVC by a bovine pericardial prosthesis (January 2003 to April 2010) have been studied after 1 year (if surviving) by MRI for the assessment of the conduit long-term patency. Results were compared with those of a control group of patients with normal SVC. Blood flow and area of lumen section at 3 different levels (proximal, middle, distal) were analyzed. RESULTS: Sixteen consecutive patients surviving after 1 year from surgery out of 17 (9 lung cancer, 8 mediastinal malignancy) undergoing SVC reconstruction were included. One patient died postoperatively and was not included. Sixteen patients with similar demographic characteristics were studied in the control group. Mean blood flow was 18.4±3.5 mL/sec (range 14.3 to 25.7) in patients with reconstructed SVC and 20.8±4.1 mL/sec (range 15.3 to 27.7) in the control group. Mean area of the conduit lumen section was 2.2±0.6 cm2 (range 1.6 to 3.6) at proximal level, 2.9±1.3 cm2 at middle level (range 1.3 to 5.7), and 2.1±0.9 cm2 (range 0.5 to 4) at distal level in the reconstructed group, and 2.6±0.7 cm2 (range 1.8 to 4.2), 2.7±0.7 cm2 (range 1.9 to 4.3), and 2.4±0.3 cm2 (range 1.8 to 3.1), respectively, at proximal, middle, and distal levels in the control group. Differences between the 2 groups were not significant (p>0.05). CONCLUSIONS: The MRI assessment in terms of blood flow and area of lumen section at 3 different levels confirms that bovine pericardial conduit used for SVC replacement shows an optimal patency over the long term.

Role of contrast-enhanced ultrasound in the follow-up of endo-vascular aortic aneurysm repair: an effective and safe surveillance method.

The treatment of Aortic Aneurysm disease is a growing procedure due to increase of life expectancy in Western Countries and relative incidence. In the past ten years we observed a progressive growth of endovascular over open surgery procedures with a related decline in rupture related deaths. Endo Vascular Aortic Repair [EVAR] is a well known technique of treatment of abdominal aortic aneurysms, that has changed the surgical approach to abdominal aortic aneurysms, as it is performed with low perioperative morbility and mortality rate and shorter hospital stay. However although EVAR offers immediate advantages over open surgical repair, it carries the need of close lifelong surveillance due to specific possible complications including rupture, endoleaks, graft migration and enlargement of aneurysm sac size. Contrast Enhanced Computed Tomography [CTA] is actually considered the standard reference in EVAR followup. However CTA carries high costs, radiation exposure and potential renal impairment. In the last five years several studies have been published on the role of Contrast Enhanced UltraSound [CEUS] in EVAR follow-up asserting high accuracy of this evaluation technique with absence of renal impairment, without radiation risk and at low costs. Especially since introduction of second generation Contrast Agents this evaluation technique is gaining popularity in EVAR follow-up surveillance. The diffusion of CEUS investigations by using new generation of contrast medium with appropriate software represents without any doubt an important step in the EVAR surveillance and could open up new strategies in the evaluation of endovascular aortic procedures gaining a fundamental role in EVAR follow-up.

Oesophageal GIST: MDCT findings of two cases and review of the literature.

INTRODUCTION: The imaging findings of a gastrointestinal stromal tumour (GIST) have been investigated in various studies; however, the features and the pattern of growth of an oesophageal GIST have been described only in a few reports. We present two cases studied by multidetector computed tomography (MDCT) and we review the literature. METHODS: We describe the diagnostic course and the pattern of presentation at MDCT of two GISTs arising from the oesophageal wall that show two different behaviours and prognosis. We review the literature comparing the features of an oesophageal GIST to the more frequent gastric or intestinal GISTs, evaluating the role of MDCT in the diagnosis and in the follow-up. DISCUSSION AND CONCLUSION: Oesophageal GISTs are uncommon, with less than 5% of all reported cases originating from this site of the GI tract. In our experience, the CT features of the two oesophageal GISTs appeared comparable to the imaging findings of the gastrointestinal stromal tumours of the stomach and of the small bowel, as these neoplasms show signs and a pattern of growth that are fairly characteristic. As reported in literature and appear in our experience, MDCT has an important role in the diagnostic course and in staging the disease even if a definitive diagnosis can be only made with the support of an immunohistochemical examination. In addition, MDCT is extremely useful in monitoring patients surgically or pharmacologically treated in order to evaluate the response to the therapy and the possibility of a progression of the disease.

Novel approaches for the surgical treatment of atrial fibrillation: time for a guideline revision?

Atrial fibrillation is a major health problem in Western countries, and is associated with considerable morbidity and resource consumption. Safe and reliable surgical techniques for the termination of this arrhythmia have been developed since the time of the original Cox "maze I" procedure. Novel equipment based on radiofrequency and microwave technologies can be employed to create transmural atrial lesions, even in the context of minimally invasive surgery to the atrioventricular valves via right minithoracotomy. The aim of this paper is to review the recent literature on this approach, and the clinical results in terms of arrhythmia termination and postoperative morbidity. With the aim to substantiate the practice of a simple, yet reliable, surgical ablation during minimally invasive heart valve surgery, we discuss the results of different patterns of atrial lesions having different degrees of surgical complexity. Finally, minimally invasive epicardial ablation for lone atrial fibrillation represents an emerging surgical indication. The results of state-of-the-art transcatheter ablation represent now its benchmark of comparison.

Sub-acute intramural haematoma of the ascending aorta.

We report the case of an ascending aorta aneurysm with intramural haematoma (IMH) in a patient with severe hypotension without history of thoracic pain or hypertension. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) demonstrated the presence of subacute IMH and also revealed sacciform aneurysm of the aortic arch. The patient refused hospitalization and one week later he underwent emergency aortic replacement for dissection. CTA is the technique of choice in acute aortic syndrome and magnetic resonance is helpful in IMH detection and age determination.

Dual energy CT (DECT) of the liver: conventional versus virtual unenhanced images.

OBJECTIVE: To compare image quality and noise of conventional unenhanced (CU) and virtual unenhanced (VU) images in patients who underwent hepatic dual energy computed tomography (DECT) and to assess potential radiation dose reduction. MATERIALS AND METHODS: Forty consecutive patients were studied. Mean CU and VU image quality and noise were analyzed by two blinded radiologists using a five-point grade scale. The effective radiation dose of a triple-phase protocol (CU, arterial and DE portal phases) were compared with that of a dual-phase protocol (arterial and DE portal phases). RESULTS: No significant difference in mean image quality was observed between VU (3.92 ± 0.85) and CU images (4.20 ± 0.72). A significant difference in mean image noise was observed between VU and CU (P < 0.01). The dose reduction achieved by omitting the unenhanced acquisition was 30.47 ± 7.07% (P < 0.01). In 6 patients, a complete VU liver image was not obtained. CONCLUSIONS: VU images can be obtained with similar image quality as CU. This approach favors a reduction in patient's radiation exposure. Nevertheless, a complete abdominal DECT is possible only in patients with a low body mass index, due technical limitations of the present DECT systems.

Imaging of leiomyosarcoma of the inferior vena cava: comparison of 2 cases and review of the literature.

Leiomyosarcoma of the inferior vena cava is a rare tumour arising from the smooth muscle fibres of the media with a mean size at diagnosis generally around 12 cm (range 2-38 cm). This study compares a 4-cm leiomyosarcoma of the inferior vena cava discovered incidentally with a symptomatic late stage leiomyosarcoma.

Morphological and functional evaluation of intrapericardial cyst as a cause of severe right heart failure: dual source computed tomography and magnetic resonance imaging.

A case of an intrapericardial cyst causing heart failure due to right ventricular compression is presented. Characterization of the lesion and its repercussion on right ventricular function by means of state-of-the-art dual source computed tomography (DSCT) and magnetic resonance imaging (MRI) is shown. The diagnosis of intrapericardial cyst was confirmed after surgical excision and biopsy. Usefulness of these noninvasive techniques for the diagnosis of this rare entity is emphasized.

A large porocarcinoma of perineal region: MR findings and review of the literature.

We present the case of a 54-year-old woman affected by a large perineal region eccrine porocarcinoma, with a wide local invasion. We discuss the clinical presentation and the imaging findings and review the literature.

Cystic lymphangioma of the upper extremity: US and MRI correlation (2004:11b).

The authors described a very rare case of the cystic lymphangioma (CL) of the left upper extremity in a 12-year-old patient. The diagnosis was made by US and MRI and confirmed by histological examination of the resected specimen.