Imaging of paraduodenal pancreatitis:A systematic review

BACKGROUND Paraduodenal pancreatitis(PP)represents a diagnostic challenge,especially in non-referral centers,given its potential imaging overlap with pancreatic cancer.There are two main histological variants of PP,the cystic and the solid,with slightly different imaging appearances.Moreover,imaging findings in PP may change over time because of disease progression and/or as an effect of its risk factors exposition,namely alcohol intake and smoking.AIM To describe multimodality imaging findings in patients affected by PP to help clinicians in the differential diagnosis with pancreatic cancer.METHODS The systematic review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-analyses 2009 guidelines.A Literature search was performed on PubMed,Embase and Cochrane Library using(groove pancreatitis[Title/Abstract])OR(PP[Title/Abstract])as key words.A total of 593 articles were considered for inclusion.After eliminating duplicates,and title and abstract screening,53 full-text articles were assessed for eligibility.Eligibility criteria were:Original studies including 8 or more patients,fully written in English,describing imaging findings in PP,with pathological confirmation or clinical-radiological follow-up as the gold standard.Finally,14 studies were included in our systematic review.RESULTS Computed tomography(CT)findings were described in 292 patients,magnetic resonance imaging(MRI)findings in 231 and endoscopic ultrasound(EUS)findings in 115.Duodenal wall thickening was observed in 88.8%of the cases:Detection rate was 96.5%at EUS,91.0%at MRI and 84.1%at CT.Second duodenal portion increased enhancement was recognizable in 76.3%of the cases:Detection rate was 84.4%at MRI and 72.1%at CT.Cysts within the duodenal wall were detected in 82.6%of the cases:Detection rate was 94.4%at EUS,81.9%at MRI and 75.7%at CT.A solid mass in the groove region was described in 40.9%of the cases;in 78.3%of the cases,it showed patchy enhancement in the portal venous phase,and in 100%appeared iso/hyperintense during delayed phase imaging.Only 3.6%of the lesions showed restricted diffusion.The prevalence of radiological signs of chronic obstructive pancreatitis,namely main pancreatic duct dilatation,pancreatic calcifications,and pancreatic cysts,was extremely variable in the different articles.CONCLUSION PP has peculiar imaging findings.MRI is the best radiological imaging modality for diagnosing PP,but EUS is more accurate than MRI in depicting duodenal wall alterations.

Non-invasive diagnostic imaging of colorectal liver metastases

Colorectal cancer is one of the few malignant tumors in which synchronous or metachronous liver metastases [colorectal liver metastases(CRLMs)] may be treated with surgery. It has been demonstrated that resection of CRLMs improves the long-term prognosis. On the other hand, patients with un-resectable CRLMs may benefit from chemotherapy alone or in addition to liverdirected therapies. The choice of the most appropriate therapeutic management of CRLMs depends mostly on the diagnostic imaging. Nowadays, multiple non-invasive imaging modalities are available and those have a pivotal role in the workup of patients with CRLMs. Although extensive research has been performed with regards to the diagnostic performance of ultrasonography, computed tomography, positron emission tomography and magnetic resonance for the detection of CRLMs, the optimal imaging strategies for staging and follow up are still to be established. This largely due to the progressive technological and pharmacological advances which are constantly improving the accuracy of each imaging modality. This review describes the non-invasive imaging approaches of CRLMs reporting the technical features, the clinical indications, the advantages and the potential limitations of each modality, as well as including some information on the development of new imaging modalities, the role of new contrast media and the feasibility of using parametric image analysis as diagnostic marker of presence of CRLMs.

影响影像引导下芯针穿刺骨骼软组织病变诊断率因素的探讨

目的评价病变特征及技术因素对影像引导下芯针穿刺(CNB)骨骼软组织病变诊断率的影响。材料与方法本研究为前瞻性研究。

Comparison of different magnetic resonance imaging sequences for assessment of fistula-in-ano

AIM: To assess agreement between different forms of T2 weighted imaging(T2WI), and post-contrast T1WI in the depiction of fistula tracts, inflammation, and internal openings with that of a reference test. METHODS: Thirty-nine consecutive prospective cases were enrolled. The following sequences were used for T2WI: 2D turbo-spin-echo(2D T2 TSE); 3D T2 TSE; short tau inversion recovery(STIR); 2D T2 TSE with fat saturation performed in all patients. T1WI were either a 3D T1-weighted prepared gradient echo sequence with fat saturation or a 2D T1 fat saturation [Spectral presaturation with inversion(SPIR)]. Agreement for each sequence for determination of fistula extension, internal openings, and the presence of active inflammation was assessed separately and blindly against a reference test comprised of follow-up, surgery, endoscopic ultrasound, and assessment by an independent experienced radiologist with access to all images.RESULTS: Fifty-six fistula tracts were found: 2 intersphincteric, 13 trans-sphincteric, and 24 with additional tracts. The best T2 weighted sequence for depiction of fistula tracts was 2D T2 TSE(Cohen's kappa = 1.0), followed by 3D T2 TSE(0.88), T2 with fat saturation(0.54), and STIR(0.19). Internal openings were best seen on 2D T2 TSE(Cohen's kappa = 0.88), followed by 3D T2 TSE(0.70), T2 with fat saturation(0.54), and STIR(0.31). Detection of inflammation showed Cohen's kappa of 0.88 with 2D T2 TSE, 0.62 with 3D T2 TSE, 0.63 with STIR, and 0.54 with T2 with fat saturation. STIR, 3D T2 TSE, and T2 with fat saturation did not make any contributions compared to 2D T2 TSE. Post-contrast 3D T1 weighted prepared gradient echo sequence with fat saturation showed better agreement in the depiction of fistulae(Cohen's kappa = 0.94), finding internal openings(Cohen's kappa = 0.97), and evaluating inflammation(Cohen's kappa = 0.94) compared to post-contrast 2D T1 fat saturation or SPIR where the corresponding figures were 0.71, 0.66, and 0.87, respectively. Comparing the best T1 and T2 sequences showed that, for best results, both sequences were necessary. CONCLUSION: 3D T1 weighted sequences were best for the depiction of internal openings and active inflammatory components, while 2D T2 TSE provided the best assessment of fistula extension.

Radioembolization for the treatment of unresectable hepatocellular carcinoma:A clinical review

Hepatocellular carcinoma(HCC)is the sixth most common cancer in the world.The majority of patients with HCC present with unresectable disease.These patients have historically had limited treatment options secondary to HCC demonstrating chemoresistance to the currently available systemic therapies.Additionally, normal liver parenchyma has shown intolerance to tumoricidal radiation doses,limiting the use of external beam radiation.Because of these limitations,novel percutaneous liver-directed therapies have emerged. The targeted infusion of radioactive microspheres (radioembolization)represents one such therapy. Radioembolization is a minimally invasive transcatheter therapy through which radioactive microspheres are infused into the hepatic arteries that supply tumor. Once infused,these microspheres traverse the hepatic vascular plexus and selectively implant within the tumor arterioles.Embedded within the arterioles, the 90Y impregnated microspheres emit high energy and low penetrating radiation doses selectively to the tumor.Radioembolization has recently shown promise for the treatment of patients with unresectable HCC. The objective of this review article is to highlight twocurrently available radioembolic devices(90Y,188Rh)and provide the reader with a recent review of the literature.

Radioactivity levels in soil of salt field area,Kelambakkam,Tamilnadu,India

Soil samples in and around salt field area have been analyzed for natural radioactivity concentration using gamma ray spectrometer.The activity concentration for ^(232)Th,^(238)U and ^(40)K are ranged from 27.88 to 45.27 Bq/kg, from BDL to 13.30 Bq/kg,and from 135.54 to 381.28 Bq/kg,respectively.The measured activity concentrations for these radionuclides were compared with world average activity of soil.The average activity concentration of ^(232)Th in the present study is 1.19 times higher than world median value while the activity of ^(238)U and ^(40)K is found to be lower. The absorbed dose rates due to these radionuclides were calculated.The average absorbed gamma dose rate due to the presence of ^(232)Th,^(238)U and ^(40)K in soil samples is 36.99 nGy·h^(-1).These results indicate no radiological anomaly. The data presented in this study will serve as a base line survey for primordial radionuclides concentration in the study area.

左室血栓的临床、影像和病理学特征:在经手术或病理确诊病例中比较对比增强MRI、经胸超声心动图和经食管超声心动图

Background: Left ventricular(LV) thrombus is a frequent and potentially dangerous complication of ischemic heart disease(IHD). We evaluated the clinical, imaging, and pathology characteristics of confirmed LV thrombus and compared the diagnostic value of contrast-enhanced magnetic resonance imaging(MRI) with transthoracic(TTE) and transesophageal echocardiography(TEE) for the diagnosis of LV thrombi. Methods: Between November 1997 and December 2003, 361 patients with IHD had surgical and/or pathological confirmation of presence or absence of LV thrombus. Clinical information and preoperative imaging study reports were retrospectively reviewed regarding detection of thrombus. Comparisons were made between clinical and imaging characteristics of patients with and without confirmed thrombus. Results: Left ventricular thrombus was present in 106(29%) of 361 patients in this study. Patients with thrombus had a higher incidence of recent embolic events(6.1%vs 0.8%, P< .005). In 160 patients with all 3 imaging modalities performed within 30 days of surgical or pathological confirmation, contrast-enhanced MRI showed the highest sensitivity and specificity(88%±9%and 99%±2%, respectively) compared with TTE(23%±12%and 96%±3.6%, respectively) and TEE(40%±14%and 96%±3.6%, respectively) for thrombus detection. Conclusions: Left ventricular thrombus occurs frequently in patients with IHD and is associated with risk of systemic embolization. Contrast-enhanced MRI provided the highest sensitivity and specificity for LV thrombus when compared to TTE and TEE, and should be considered in the care of patients at high risk of LV thrombus formation.

Thoracic hydatid disease:A radiologic review of unusual cases

Hydatid disease or echinococcosis is a zoonotic parasitic disease.The lung is the second most commonly affected organ after the liver.Intra-thoracic and extrapulmonary hydatid disease is uncommon and may involve the pleura,mediastinum,heart,diaphragm,and chest wall.Unusual locations or complications of thoracic hydatid disease may pose a diagnostic challenge.We present imaging findings of cases with unusual location and presentations of thoracic hydatid disease with emphasis on their clinical implications.

Traumatic peroneal split lesion with retinaculum avulsion:Diagnosis and post-operative multymodality imaging

Tears of peroneus brevis tendon represent a cause of underdiagnosed lateral ankle pain and instability. The typical clinical presentation is retro-malleolar pain, in some cases associated with palpable swelling around the fibular malleolus, pain during activities and difficulty in walking. We present a case of peroneus brevis split lesion with superior peroneal retinaculum avulsion in a young athlete who referred to the emergency ward of our hospital for left ankle pain after an inversion injury. An early diagnosis allowed treating the injury and promptly resuming sport activity, after rehabilitation training. Surgical reconstruction key-points and postsurgical follow-up were also discussed. A late diagnosis would have caused a symptomatology worsening and an increased recovery time.

Therapeutic angiography for giant bleeding gastro-duodenal artery pseudoaneurysm

We present the case of an 18-year-old female transferred to our center from an outside hospital due to persistent gastrointestinal bleeding. Two weeks prior to her transfer she underwent duodenal omentopexy for a perforated duodenal peptic ulcer. The patient underwent a computed tomography angiogram which identified the source of bleeding as a giant gastroduodenal artery (GDA) pseudoaneurysm. The patient was taken to interventional radiology where successful microcoil embolization was performed. We present this rare case of a giant GDA pseudoaneurysm together with imaging and a review of the medical literature regarding prevalence, etiology and treatment options for visceral arterial aneurysms.

Incidental vertebral compression fractures in imaging studies:Lessons not learned by radiologists

AIM:To assess radiologists reporting rates of incidental vertebral compression fractures in imaging studies. METHODS:We performed a review of the current literature on the prevalence and reporting rates of incidental vertebral compression fractures in radiologic examinations. RESULTS:The bibliographic search revealed 12 studies:7 studies using conventional radiology and 5 using multidetector computed tomography(MDCT).The lossof height cut-off to define a vertebral fracture varied from 15%to 25%.Fracture prevalence was high (mean 21.1%;range 9.5%-35%)in both radiographic and MDCT studies(mean 21.6%and 20.2%,respectively).Reporting rates were low with a mean value of 27.4%(range 0%-66.3%)and were significantly lower in MDCT than in radiographic studies(mean 8.1%vs 41.1%).Notably,recent studies showed lower reporting rates than older studies. CONCLUSION:Many scientific studies have confirmed a high prevalence of vertebral compression fractures as incidental findings on imaging studies.However,the underreporting of these fractures,as determined in our study,may negatively affect patient care.

Bifunctional staining for ex vivo determination of area at risk in rabbits with reperfused myocardial infarction

AIM: To develop a method for studying myocardial area at risk(AAR) in ischemic heart disease in correlation with cardiac magnetic resonance imaging(c MRI). METHODS: Nine rabbits were anesthetized, intubated and subjected to occlusion and reperfusion of the left circumflex coronary artery(LCx) to induce myocardial infarction(MI). ECG-triggered c MRI with delayed en-hancement was performed at 3.0 T. After euthanasia, the heart was excised with the LCx re-ligated. Bifunctional staining was performed by perfusing the aorta with a homemade red-iodized-oil(RIO) dye. The heart was then agar-embedded for ex vivo magnetic resonance imaging and sliced into 3 mm-sections. The AAR was defined by RIO-staining and digital radiography(DR). The perfusion density rate(PDR) was derived from DR for the AAR and normal myocardium. The MI was measured by in vivo delayed enhancement(i DE) and ex vivo delayed enhancement(e DE) c MRI. The AAR and MI were compared to validate the bifunctional straining for cardiac imaging research. Linear regression with Bland-Altman agreement, one way-ANOVA with Bonferroni's multiple comparison, and paired t tests were applied for statistics.RESULTS: All rabbits tolerated well the surgical procedure and subsequent c MRI sessions. The openchest occlusion and close-chest reperfusion of the LCx, double suture method and bifunctional staining were successfully applied in all animals. The percentage MI volumes globally(n = 6) and by slice(n = 25) were 36.59% ± 13.68% and 32.88% ± 12.38% on i DE, and 35.41% ± 12.25% and 32.40% ± 12.34% on e DE. There were no significant differences for MI determination with excellent linear regression correspondence(r global = 0.89; r slice = 0.9) between i DE and e DE. The percentage AAR volumes globally(n = 6) and by slice(n = 25) were 44.82% ± 15.18% and 40.04% ± 13.64% with RIO-staining, and 44.74% ± 15.98% and 40.48% ± 13.26% by DR showing high correlation in linear regression analysis(r global = 0.99; r slice = 1.0). The mean differences of the two AAR measurements on BlandAltman were almost zero, indicating RIO-staining and DR were essentially equivalent or inter-replaceable. The AAR was significantly larger than MI both globally and slice-by-slice(P < 0.01). After correction with the background and the blank heart without bifunctional staining(n = 3), the PDR for the AAR and normal myocardium was 32% ± 15% and 35.5% ± 35%, respectively,which is significantly different(P < 0.001), suggesting that blood perfusion to the AAR probably by collateral circulation was only less than 10% of that in the normal myocardium.CONCLUSION: The myocardial area at risk in ischemic heart disease could be accurately determined postmortem by this novel bifunctional staining, which may substantially contribute to translational cardiac imaging research.

Features of hepatocellular carcinoma in Hispanics differ from African Americans and non-Hispanic Whites

AIM To compare features of hepatocellular carcinoma(HCC) in Hispanics to those of African Americans and Whites.METHODS Patients treated for HCC at an urban tertiary medical center from 2005 to 2011 were identified from a tumor registry. Data were collected retrospectively, including demographics, comorbidities, liver disease characteristics, tumor parameters, treatment, and survival(OS) outcomes. OS analyses were performed using Kaplan-Meier method.RESULTS One hundred and ninety-five patients with HCC were identified: 80.5% were male, and 22% were age 65 or older. Mean age at HCC diagnosis was 59.7 ± 9.8 years. Sixty-one point five percent of patients had Medicare or Medicaid; 4.1% were uninsured. Compared to African American(31.2%) and White(46.2%) patients, Hispanic patients(22.6%) were more likely to have diabetes(P = 0.0019), hyperlipidemia(P = 0.0001), nonalcoholic steatohepatitis(NASH)(P = 0.0021), end stage renal disease(P = 0.0057), and less likely to have hepatitis C virus(P < 0.0001) or a smoking history(P < 0.0001). Compared to African Americans, Hispanics were more likely to meet criteria for metabolic syndrome(P = 0.0491), had higher median MELD scores(P = 0.0159), ascites(P = 0.008), and encephalopathy(P = 0.0087). Hispanic patients with HCC had shorter OS than the other racial groups(P = 0.020), despite similarities in HCC parameters and treatment. CONCLUSION In conclusion, Hispanic patients with HCC have higher incidence of modifiable metabolic risk factors including NASH, and shorter OS than African American and White patients.

High rate of complete histopathological response in hepatocellular carcinoma patients after combined transarterial chemoembolization and stereotactic body radiation therapy

BACKGROUND Liver transplantation(LT)presents a curative treatment option in patients with early stage hepatocellular carcinoma(HCC)who are not eligible for resection or ablation therapy.Due to a risk of up 30%for waitlist drop-out upon tumor progression,bridging therapies are used to halt tumor growth.Transarterial chemoembolization(TACE)and less commonly stereotactic body radiation therapy(SBRT)or a combination of TACE and SBRT,are used as bridging therapies in LT.However,it remains unclear if one of those treatment options is superior.The analysis of explant livers after transplantation provides the unique opportunity to investigate treatment response by histopathology.AIM To analyze histopathological response to a combination of TACE and SBRT in HCC in comparison to TACE or SBRT alone.METHODS In this multicenter retrospective study,27 patients who received liver transplantation for HCC were analyzed.Patients received either TACE or SBRT alone,or a combination of TACE and SBRT as bridging therapy to liver transplantation.Liver explants of all patients who received at least one TACE and/or SBRT were analyzed for the presence of residual vital tumor tissue by histopathology to assess differences in treatment response to bridging therapies.Statistical analysis was performed using Fisher-Freeman-Halton exact test,Kruskal-Wallis and Mann-Whitney-U tests.RESULTS Fourteen patients received TACE only,four patients SBRT only,and nine patients a combination therapy of TACE and SBRT.There were no significant differences between groups regarding age,sex,etiology of underlying liver disease or number and size of tumor lesions.Strikingly,analysis of liver explants revealed that almost all patients in the TACE and SBRT combination group(8/9,89%)showed no residual vital tumor tissue by histopathology,whereas TACE or SBRT alone resulted in significantly lower rates of complete histopathological response(0/14,0%and 1/4,25%,respectively,P value<0.001).CONCLUSION Our data suggests that a combination of TACE and SBRT increases the rate of complete histopathological response compared to TACE or SBRT alone in bridging to liver transplantation.

Diagnostic challenges in Salla disease

Sialic acid storage disease (Salla disease) is an autosomal recessive disorder caused by mutations in a lysosomal sialic acid export protein, SLC17A5 (OMIM #604369). This disorder was initially described in Northern Finland but more recently has been reported in patients of other ethnicities. We describe the clinical presentation and the neuroimaging findings of two non-Finnish children where a diagnosis of Salla disease was suspected on the basis of brain magnetic resonance imaging. The biochemical confirmation of this diagnosis posed a challenge as both patients had elevated percent free urine sialic acid but biochemical analyses in fibroblasts were not conclusive;therefore, molecular testing was necessary for confirmation of the diagnosis. The described encounters demonstrate the importance of pursuing confirmatory molecular diagnostic testing when a sialic acid storage disorder is suspected.

Advances in Y-90 radioembolization for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma remains a prominent cause of cancer-related mortality globally.Transarterial yttrium-90 radioembolization is a versatile therapy and plays an important role in the treatment of hepatocellular carcinoma.This review summarizes the establishment of radioembolization in the hepatocellular carcinoma treatment paradigm,treatment considerations across cancer stages,and recent advances in evidence.