Horseshoe Kidney Blunt Trauma With Double Laceration: Endovascular Management.

A 78-year-old male patient was admitted to our hospital after abdominal trauma. Contrast-enhanced computed tomography (CT) scan demonstrated a horseshoe kidney with a perinephric hematoma and evidence of arterial hemorrhage. An anomalous renal arterial anatomy was noted as well, with a renal artery originating from the left common iliac artery. He was successfully treated via an endovascular approach. Varying forms of vascularization may complicate angiographic treatment of patients with abdominal trauma in a setting of kidney anomalies. Obtaining and evaluating contrast-enhanced CT angiography can identify anomalous vessels and can be invaluable when deciding on the most appropriate interventional approach.

Prevent Pancreatic Fistula after Pancreatoduodenectomy: Possible Role of Ultrasound Elastography.

BACKGROUND: The purpose of the study is to evaluate the utility of acoustic radiation force impulse (ARFI) on pancreatic tissue as a preoperative predictor of postoperative pancreatic fistula (POPF). Studied patients underwent exclusively to pancreaticoduodenectomy (PD) surgery. METHODS: Shear wave velocity of pancreas was measured using ARFI in 71 patients scheduled for PD. An intraoperative pancreas palpation was made by surgeons. A postoperative clinical evaluation to detect occurrence of POPF was performed. Sensitivity, specificity, positive and negative predictive values together with the accuracy of the method were investigated. RESULTS: Incidence of fistula observed in 17 patients with soft pancreas was approximately 53% vs. 47% without fistula. Percentage of patients without fistula was higher (66%) among 24 patients with medium parenchymal texture values, and was even higher (69%) in 26 patients with hard pancreas. Comparing ARFI and intraoperative pancreatic palpation, low wave velocity values (≤1.40 m/s) match 60% with soft parenchyma assessed by palpation and high values (>2 m/s) match 59% with hard pancreas on palpation. CONCLUSIONS: This study shows that ARFI elastography may be clinically useful as a preoperative predictor of pancreatic fistula following PD.

Perfusion CT Changes in Liver Metastases from Pancreatic Neuroendocrine Tumors During Everolimus Treatment.

AIM: To evaluate modifications of perfusional parameters assessed by perfusion computed tomography (P-CT) of liver metastases (LM) from pancreatic neuroendocrine tumors (PanNETs) during everolimus treatment. PATIENTS AND METHODS: All patients with LMs from G1-2 PanNETs undergoing everolimus treatment between January 2013 and January 2015 were prospectively evaluated with P-CT at baseline, and after 2 and 4 months of therapy. Size, perfusion, blood volume (BV), peak enhancement intensity (PEI) and time to peak for each lesion were calculated. RESULTS: A total of 33 LMs in nine patients with G1-2 PanNETs were prospectively evaluated: 23/33 (69.7%) were responders, 10/33 (30.3%) were non-responders. Among perfusional parameters, only numerical peak enhancement intensity values significantly differed between the two groups at baseline (p=0.043). BV increase was the most significant perfusional modification identifying responding lesions, even at an early stage of treatment, with a high positive predictive value (89.47%). CONCLUSION: P-CT seems to be useful for prediction of response to everolimus of LMs from PanNETs.

Percutaneous Radiofrequency Ablation of Unresectable Locally Advanced Pancreatic Cancer: Preliminary Results.

AIM: The objective of this study was to evaluate the efficacy of percutaneous radiofrequency ablation of locally advanced pancreatic cancer located in the pancreatic body. MATERIALS AND METHODS: Patients with biopsy-proven locally advanced pancreatic adenocarcinoma were considered for percutaneous radiofrequency ablation. Postprocedural computed tomography studies and Ca19.9 tumor marker evaluation were performed at 24 hours and 1 month. At computed tomography, treatment effect was evaluated by excluding the presence of complications. The technical success of the procedure is defined at computed tomography as the achievement of tumoral ablated area. RESULTS: Twenty-three patients have been included in the study. Five of the 23 patients were excluded. At computed tomography, the mean size of the intralesional postablation necrotic area was 32 mm (range: 15-65 mm). Technical success of the procedure has been obtained in 16 (93%) of the 18 cases. None of the patients developed postprocedural complications. Mean Ca19.9 serum levels 1 day before, 1 day after, and 1 month after the procedure were 285.8 U/mL (range: 16.6-942.0 U/mL), 635.2 U/mL (range: 17.9-3368.0 U/mL), and 336.0 U/mL (range: 7.0-1400.0 U/mL), respectively. Follow-up duration was less than 6 months for 11 patients and more than 6 months for 7 patients. At the time of the draft of this article, the mean survival of the patients included in the study was 185 days (range: 62-398 days). CONCLUSION: Percutaneous radiofrequency ablation of locally advanced adenocarcinoma has a high technical success rate and is effective in cytoreduction both at imaging and laboratory controls.

Variation of tumoral marker after radiofrequency ablation of pancreatic adenocarcinoma.

BACKGROUND: To evaluate the correlation between variations of CA 19.9 blood levels and the entity of necrosis at CT after radiofrequency ablation (RFA) of unresectable pancreatic adenocarcinoma. METHODS: In this study, from June 2010 to February 2014, patients with diagnosis of unresectable and not metastatic pancreatic ductal adenocarcinoma, expressing tumor marker CA 19.9, treated with RFA procedure were included. All these patients underwent RFA. CT study was performed 1 week after RFA. The dosage of CA 19.9 levels was performed 1 month after RFA. Features of necrosis at CT, as mean entity, density and necrosis percentages compared to the original lesion, were evaluated and compared by using t-test with CA 19.9 blood levels variations after RFA procedure. RESULTS: In this study were included 51 patients with diagnosis of unresectable and not metastatic pancreatic ductal adenocarcinoma, expressing tumor marker CA 19.9, treated with RFA procedure and with CT study and CA 19.9 available for analysis. After the procedure, CA 19.9 blood levels reduced in 24/51 (47%), remained stable in 10/51 (20%) and increased in 17/51 (33%). In patients with CA 19.9 levels reduced, the tumor marker were reduced less than 20% in 4/24 (17%) and more than 20% in 20/24 (83%); instead the tumor marker were reduced less than 30% in 8/24 (33%) and more than 30% in 16/24 (67%). At CT scan necrotic area density difference was not statistically significant. Also there was no statistically significant difference among the mean area, the mean volume and the mean ablation volume in percentage related to the treated tumor among the three different groups of patients divided depending on the CA 19.9 blood levels. But a tendency to a statistically significant difference was found in comparing the mean percentage of ablation volume between two subgroups of patients with a decrease of CA 19.9 levels with less or more than 20% reduction of tumor markers and between two subgroups with less or more than 30% reduction of CA 19.9 levels. CONCLUSIONS: RFA of unresectable pancreatic adenocarcinoma induces reduction of CA 19.9 blood levels in about half of the cases.

Acoustic radiation force impulse with shear wave speed quantification of pancreatic masses: A prospective study.

BACKGROUND: Acoustic Radiation Force Impulse (ARFI) is a new ultrasound technique that evaluates mechanical properties of tissues. To evaluate the use of ARFI with shear waves speed quantification for pancreatic masses characterization during the ultrasound examination. METHODS: 123 pancreatic lesions were prospectively evaluated. Median shear waves speeds were compared with Mann-Whitney U test. Two reading methods were applied for the characterization of adenocarcinoma: more than one measurement above the top shear waves speed (SWS) value. Two reading methods were applied to diagnose mucinous lesion: at least 2 (method 1) or 3 (method 2) numerical measurements. Sensitivity, specificity, positive and negative predictive values and accuracy of each reading method were calculated. Forty volunteers were included for normal ARFI values. RESULTS: In the adenocarcinoma group median SWS value was 2.74 m/s. In the volunteers group the median SWS value was 1.17 m/s. Significant difference between SWS median values of adenocarcinoma and normal pancreas was found (P < 0.05). For the diagnosis of pancreatic solid masses if more than one measurement is above the top SWS value of 4.00 m/s results in the study, the diagnosis of ductal adenocarcinoma is highly specific with specificity and PPV of 100%. Good sensitivity (73.3%) and specificity (83.3%) were obtained for the characterization of mucinous cystic lesions. CONCLUSIONS: Acoustic Radiation Force Impulse imaging could help in the non-invasive characterization of solid and cystic lesions of the pancreas during a conventional US examination.

Contrast-Enhanced Ultrasound of Focal Liver Lesions.

OBJECTIVE: The purpose of this article is to discuss the use of contrast-enhanced ultra-sound (CEUS) in focal liver lesions. CONCLUSION: Focal liver lesions are usually detected incidentally during abdominal ultrasound. The injection of microbubble ultrasound contrast agents improves the characterization of focal liver lesions that are indeterminate on conventional ultrasound. The use of CEUS is recommended in official guidelines and suggested as a second diagnostic step after ultrasound detection of indeterminate focal liver lesions to immediately establish the diagnosis, especially for benign liver lesions, such as hemangiomas, avoiding further and more expensive examinations.

Uncommon presentations of common pancreatic neoplasms: a pictorial essay.

Pancreatic neoplasms are a wide group of solid and cystic lesions with different and often characteristic imaging features, clinical presentations, and management. Among solid tumors, ductal adenocarcinoma is the most common: it arises from exocrine pancreas, comprises about 90% of all pancreatic neoplasms, and generally has a bad prognosis; its therapeutic management must be multidisciplinary, involving surgeons, oncologists, gastroenterologists, radiologists, and radiotherapists. The second most common solid pancreatic neoplasms are neuroendocrine tumors: they can be divided into functioning or non-functioning and present different degrees of malignancy. Cystic pancreatic neoplasms comprise serous neoplasms, which are almost always benign, mucinous cystic neoplasms and intraductal papillary mucinous neoplasms, which can vary from benign to frankly malignant lesions, and solid pseudopapillary tumors. Other pancreatic neoplasms, such as lymphoma, metastases, or pancreatoblastoma, are rarely seen in clinical practice and have different and sometimes controversial managements. Rare clinical presentations and imaging appearance of the most common pancreatic neoplasms, both solid and cystic, are more frequently seen and clinically relevant than rare pancreatic tumors; their pathologic and radiologic appearances must be known to improve their management. The purpose of this paper is to present some rare or uncommon clinical and radiological presentations of common pancreatic neoplasms providing examples of multi-modality imaging approach with pathologic correlations, thus describing the histopathological bases that can explain the peculiar imaging features, in order to avoid relevant misdiagnosis and to improve lesion management.

CEUS of the pancreas: Still research or the standard of care.

Contrast-enhanced ultrasonography (CEUS) improves the characterization of pancreatic masses. CEUS is in fact a safe and accurate imaging method to evaluate the vascularity of pancreatic lesions. CEUS should be performed when possible immediately after the ultrasound (US) detection of a pancreatic mass. CEUS is accurate in the characterization of ductal adenocarcinoma. The use of CEUS in studying pancreatic lesions found at US, especially in the same session of ultrasound examination, is therefore recommendable to promote faster diagnosis mainly of pancreatic ductal adenocarcinoma.

Autoimmune pancreatitis: Multimodality non-invasive imaging diagnosis.

Autoimmune pancreatitis (AIP) is characterized by obstructive jaundice, a dramatic clinical response to steroids and pathologically by a lymphoplasmacytic infiltrate, with or without a pancreatic mass. Type 1 AIP is the pancreatic manifestation of an IgG4-related systemic disease and is characterized by elevated IgG4 serum levels, infiltration of IgG4-positive plasma cells and extrapancreatic lesions. Type 2 AIP usually has none or very few IgG4-positive plasma cells, no serum IgG4 elevation and appears to be a pancreas-specific disorder without extrapancreatic involvement. AIP is diagnosed in approximately 2%-6% of patients that undergo pancreatic resection for suspected pancreatic cancer. There are three patterns of autoimmune pancreatitis: diffuse disease is the most common type, with a diffuse, "sausage-like" pancreatic enlargement with sharp margins and loss of the lobular contours; focal disease is less common and manifests as a focal mass, often within the pancreatic head, mimicking a pancreatic malignancy. Multifocal involvement can also occur. In this paper we describe the features of AIP at ultrasonography, computed tomography, magnetic resonance and positron emission tomography/computed tomography imaging, focusing on diagnosis and differential diagnosis with pancreatic ductal adenocarcinoma. It is of utmost importance to make an early correct differential diagnosis between these two diseases in order to identify the optimal therapeutic strategy and to avoid unnecessary laparotomy or pancreatic resection in AIP patients. Non-invasive imaging plays also an important role in therapy monitoring, in follow-up and in early identification of disease recurrence.

Noninvasive diagnosis of cirrhosis: a review of different imaging modalities.

Progressive hepatic fibrosis can lead to cirrhosis, so its early detection is fundamental. Staging fibrosis is also critical for prognosis and management. The gold standard for these aims is liver biopsy, but it has several drawbacks, as it is invasive, expensive, has poor acceptance, is prone to inter observer variability and sampling errors, has poor repeatability, and has a risk of complications and mortality. Therefore, non-invasive imaging tests have been developed. This review mainly focuses on the role of transient elastography, acoustic radiation force impulse imaging, and magnetic resonance-based methods for the noninvasive diagnosis of cirrhosis.

Time-to-peak values can estimate hepatic functional reserve in patients undergoing surgical resection: a comparison between perfusion CT and indocyanine green retention test.

OBJECTIVE: To evaluate the potential usefulness of perfusion computed tomography (CT) for the estimation of hepatic functional reserve in patients scheduled for surgical resection and to compare the results with those of the indocyanine green retention test results. METHODS: Thirty-one patients with hepatobiliary malignancies were included. Perfusion CT and indocyanine green retention test were performed on the same day, and their results were compared using Pearson correlation test. RESULTS: A strong correlation was found between perfusion CT time-to-peak values and indocyanine green retention rate at 15 minutes and indocyanine green plasma disappearance rate values (R, 0.789 and -0.790; R, 0.832 and -0.823, respectively; P < 0.0001). CONCLUSIONS: Perfusion CT may be useful for the preoperative noninvasive estimation of hepatic functional reserve for patients undergoing liver resection.

Contrast enhanced ultrasound with quantitative perfusion analysis for objective characterization of pancreatic ductal adenocarcinoma: A feasibility study.

The aim of this study was to determine whether contrast enhanced ultrasound (CEUS) quantitative perfusion analysis allows an objective characterization of ductal adenocarcinoma (ADK) of the pancreas. Patients with pancreatic ADK underwent CEUS. All examinations were performed on an Acuson S2000 system (Siemens, Erlangen, Germany) after the iv administration of 2.4 mL contrast agent (SonoVue(®), Bracco, Milan, Italy). All lesions were pathologically proved. An operator manually drew different regions of interest within the tumor and the adjacent parenchyma to allow the quantitative perfusion analysis. The mean values of peak of enhancement, time to peak and ascending curve were calculated and compared using the Student's t test. The quantitative perfusion analysis was possible in all lesions. The mean values of the peak of enhancement, time to peak and ascending curve were 17.19%, 7.97 s and 159.52% s within the tumor and 33.57%, 8.89 s and 355.29% s within the adjacent parenchyma. The peak of enhancement and the ascending curve values were significantly different within the tumor and the adjacent parenchyma. Thus, CEUS allows the quantitative perfusion analysis of pancreatic ductal adenocarcinoma.

Liver volumetry: Is imaging reliable? Personal experience and review of the literature.

The amount of the future liver remnant volume is fundamental for hepato-biliary surgery, representing an important potential risk-factor for the development of post-hepatectomy liver failure. Despite this, there is no uniform consensus about the amount of hepatic parenchyma that can be safely resected, nor about the modality that should be chosen for this evaluation. The pre-operative evaluation of hepatic volume, along with a precise identification of vascular and biliar anatomy and variants, are therefore necessary to reduce surgical complications, especially for extensive resections. Some studies have tried to validate imaging methods [ultrasound, computed tomography (CT), magnetic resonance imaging] for the assessment of liver volume, but there is no clear evidence about the most accurate method for this evaluation. Furthermore, this volumetric evaluation seems to have a certain degree of error, tending to overestimate the actual hepatic volume, therefore some conversion factors, which should give a more reliable evaluation of liver volume, have been proposed. It is widespread among non-radiologists the use of independent software for an off-site volumetric analysis, performed on digital imaging and communications in medicine images with their own personal computer, but very few studies have provided a validation of these methods. Moreover, while the pre-transplantation volumetric assessment is fundamental, it remains unclear whether it should be routinely performed in all patients undergoing liver resection. In this editorial the role of imaging in the estimation of liver volume is discussed, providing a review of the most recent literature and a brief personal series of correlations between liver volumes and resection specimens' weight, in order to assess the precision of the volumetric CT evaluation.

Elastography of the pancreas.

Elastography has recently been presented in clinical studies as a new technique applied to US imaging. The challenge of this new technique is to distinguish different tissues on the basis of their specific consistency. Since malignant tumors tend to be harder than benign lesions and parenchyma, this new approach could result clinically relevant. Initial clinical experiences in US elastography have been promising in differentiating breast, thyroid and prostate nodules. Pancreatic applications of US elastography are relatively recent and under validation with several studies so far published in literature.

Contrast-enhanced ultrasound of pancreatic tumours.

Indication/purpose: To review contrast-enhanced ultrasound features of the most common pancreatic tumours. Methods: Contrast-enhanced ultrasound (CEUS) can provide distinctive features of pancreatic tumours that are reported in the present paper, providing radiologic-pathological correlations and clarifying the main differential diagnosis. Conclusion: Contrast-enhanced ultrasound plays a well-established role in the evaluation of pancreatic tumours. When possible, CEUS should be always performed after the initial US diagnosis, in order to improve the accuracy of the first line examination.

Acoustic radiation force impulse of the liver.

Acoustic radiation force impulse (ARFI) imaging is a new and promising ultrasound-based diagnostic technique that, evaluating the wave propagation speed, allows the assessment of the tissue stiffness. ARFI is implemented in the ultrasound scanner. By short-duration acoustic radiation forces (less than 1 ms), localized displacements are generated in a selected region of interest not requiring any external compression so reducing the operator dependency. The generated wave scan provides qualitative or quantitative (wave velocity values) responses. Several non-invasive methods for assessing the staging of fibrosis are used, in order to avoid liver biopsy. Liver function tests and transient elastography are non-invasive, sensitive and accurate tools for the assessment of liver fibrosis and for the discrimination between cirrhotic and non-cirrhotic liver. Many published studies analyse ARFI performance and feasibility in studying diffuse liver diseases and compare them to other diagnostic imaging modalities such as conventional ultrasonography and transient elastography. Solid focal liver lesions, both benign and malignant, are common findings during abdominal examinations. The accurate characterization and differential diagnosis are important aims of all the imaging modalities available today. Only few papers describe the application of ARFI technology in the study of solid focal liver lesions, with different results. In the present study, the existing literature, to the best of our knowledge, about ARFI application on diffuse and focal liver pathology has been evaluated and results and statistical analyses have been compared, bringing to the conclusion that ARFI can be used in the study of the liver with similar accuracy as transient elastography in diagnosing significant fibrosis or cirrhosis and has got some advantages in respect to transient elastography since it does not require separate equipment, better displays anatomical structures and measurements can be successfully carried out almost in every patient.

A rare case of incidental pancreatic arteriovenous malformation correctly diagnosed with MDCT.

CONTEXT: Pancreatic arteriovenous malformations are a rare entity that can be incidentally discovered during MDCT examinations. CASE REPORT: We describe a rare case of asymptomatic arteriovenous malformation presenting at MDCT as a hypervascular mass in the pancreatic head. CONCLUSION: Pancreatic arteriovenous malformations are a rare entity, often asymptomatic, that can be correctly diagnosed by MDCT, especially with the use of specific electronic reconstructions.