CTContour: An open-source Python pipeline for automatic contouring and calculation of mean SSDE along the abdomino-pelvic region for CT images; validation on fifteen systems.

PURPOSE: Calculation of the Size Specific Dose Estimate (SSDE) requires accurate delineation of the skin boundary of patient CT slices. The AAPM recommendation for SSDE evaluation at every CT slice is too time intensive for manual contouring, prohibiting real-time or bulk processing; an automated approach is therefore desirable. Previous automated delineation studies either did not fully disclose the steps of the algorithm or did not always manage to fully isolate the patient. The purpose of this study was to develop a validated, freely available, fast, vendor-independent open-source tool to automatically and accurately contour and calculate the SSDE for the abdomino-pelvic region for entire studies in real-time, including flagging of patient-truncated images. METHODS: The Python tool, CTContour, consists of a sequence of morphological steps and scales over multiple cores for speed. Tool validation was achieved on 700 randomly selected slices from abdominal and abdomino-pelvic studies from public datasets. Contouring accuracy was assessed visually by four medical physicists using a 1-5 Likert scale (5 indicating perfect contouring). Mean SSDE values were validated via manual calculation. RESULTS: Contour accuracy validation produced a score of four of five for 98.5 % of the images. A 300 slice exam was contoured and truncation flagged in 6.3 s on a six-core laptop. CONCLUSIONS: The algorithm was accurate even for complex clinical scenarios and when artefacts were present. Fast execution makes it possible to automate the calculation of SSDE in real time. The tool has been published on GitHub under the GNU-GPLv3 license.

Neurofibromatosis Type 1: A Rare Predisposition for Gastrinomas and Other Neuroendocrine Tumors.

ABSTRACT: Neurofibromatosis type (NF-1) is an autosomal dominant disorder characterized predominantly by neurocutaneous manifestations. Involvement of the gastrointestinal tract is uncommon but is associated with a significant risk of malignancy. There are a handful of case reports linking NF-1 with pancreatic neuroendocrine tumors; these include gastrin-secreting variants with the attendant Zollinger-Ellison syndrome. We present the case of a 52-year-old lady who presented with recurrent peptic ulceration and diarrhea. Serum gastrin levels were elevated and magnetic resonance imaging demonstrated the presence of a pancreatic lesion with multiple liver metastases. The lesion was moderately fludeoxyglucose avid on positron emission tomography-computed tomography. Endoscopic ultrasonography-guided sampling revealed the presence of synaptophysin positive neuroendocrine cells with positive gastrin immunostaining. A conservative approach was adopted, and the patient's symptoms improved on proton pump inhibitors. Zollinger-Ellison syndrome is an important condition, which should be kept in mind in the patient with NF-1 who presents with recurrent peptic ulceration and diarrhea. The emerging association between these 2 conditions is being examined on a cellular and immunohistochemical level.

Portal vein puncture-related complications during transjugular intrahepatic portosystemic shunt creation: Colapinto needle set vs Rösch-Uchida needle set.

Transjugular portal vein puncture is considered the riskiest step in TIPS creation with possible incidence of portal vein puncture-related complications (PVPC). The Colapinto and the Rösch-Uchida needle sets are two different needle sets currently available. To date, there have been no randomized control trials or systematic reviews which compare the incidence of PVPC when using the two different needle sets. The aim of this literature review is to assess the rate of PVPC associated with the different needle sets used in the creation of TIPS. From the described search, 1500 articles were identified and 34 met the inclusion criteria. Outcome measured was the prevalence of PVPC using the different needle sets. Overall 212 (3.6%) PVPC were reported in 5865 patients; 142 (3.5%) reported in 4000 cases using the Rösch-Uchida set and 70 (3.7%) in 1865 patients using the Colapinto set (p = 0.69). PVPC in TIPS creation are not related to the choice of needle set used in the procedure. To our knowledge, this is the first review of its kind, the results of which support the theory that while the rate of PVPC is influenced by many factors, choice of needle set does not seem to be one of them.

ESTABLISHING LOCAL AND NATIONAL DIAGNOSTIC AND INTERVENTIONAL CARDIOLOGY AND RADIOLOGY REFERENCE LEVELS IN A SMALL EUROPEAN STATE: THE CASE OF MALTA.

European Directive 2013/59/EURATOM requires the establishment and use of diagnostic reference levels (DRLs) for diagnostic and interventional procedures. The purpose of this study was to establish local DRLs for a major tertiary public hospital. As the hospital is the only such hospital in Malta, the same data collected for setting local DRLs can also be used for setting national DRLs, making local DRLs de facto national DRLs. A retrospective survey of cumulative kerma-area product (KAP) and fluoroscopy time data from the cardiac catheterisation laboratory and interventional radiology suites was carried out. The effect of system upgrades on cumulative KAP was also assessed. Local DRLs were set for common cardiology and interventional radiology procedures. All DRLs compare favourably with those in European literature. A Philips Allura Clarity upgrade to the cardiac catheterisation laboratories led to significant reductions in cumulative KAP (p â‰ª  0.05) for most procedures.

Hepatic Necrosis after Trans-Arterial Embolization of Metastatic Neuroendocrine Tumour.

Liver metastases from neuroendocrine tumours (NETs) are usually seen on cross-sectional imaging at presentation. In such cases, curative surgical resection is usually not possible given that most patients have bilobar disease. Various locoregional approaches are now widely available that enable local control of disease and management of systemic symptoms. These include trans-arterial embolization (TAE), trans-arterial chemoembolization (TACE), selective internal radiotherapy and thermal ablation. We describe a rare case of hepatic necrosis after TAE in a 61-year-old woman with a metastatic NET. Cross-sectional imaging showed extensive necrosis affecting segments VII and VIII of the liver. This occurred secondary to thrombosis in the portal vein branches to these segments, confirmed on a Doppler ultrasound scan. The mechanism of portal vein thrombosis after TAE could be due to the presence of occult arterioportal anastomoses. These allow transit of the embolizing agents into the portal vein branches supplying the treated segments and subsequent thrombosis. LEARNING POINTS: Hepatic necrosis is a very rare but significant complication of TAE. The incidence of this complication after TAE has not yet been reported.Hepatic necrosis may be mimicked by the more commonly encountered post-embolization syndrome (PES). Hepatic necrosis should be suspected when symptoms are prolonged, or if the patient exhibits any form of deterioration. Prompt cross-sectional imaging is crucial in establishing diagnosis.Thorough supportive management is key in the setting of liver injury or failure. Sepsis should be treated aggressively with regular blood cultures and specialist input should be sought for optimization of antibiotic regimes.

Radiation exposure during transjugular intrahepatic portosystemic shunt creation in patients with complete portal vein thrombosis or portal cavernoma.

BACKGROUND: This study aims to evaluate radiation exposure in patients with complete portal vein thrombosis (CPVT) or portal cavernoma (PC) undergoing transjugular intrahepatic portosystemic shunt (TIPS) creation using real-time ultrasound guidance for portal vein targeting. MATERIALS AND METHODS: This is a single institution retrospective analysis. Between August 2009 and September 2018, TIPS was attempted in 49 patients with CPVT or PC. Radiation exposure (dose area product [DAP], air KERMA (AK) and fluoroscopy time [FT]), technical success, clinical success, complications and survival were analyzed. RESULTS: In total, 29 patients had CPVT and 20 patients had PC. 41/49 patients had cirrhosis. TIPS indications were refractory ascites (n = 25), variceal bleeding (n = 16) and other (n = 8). TIPS was successfully placed in 94% (46/49) of patients via a transjugular approach alone (n = 40), a transjugular/transhepatic approach (n = 5) and a transjugular/transsplenic approach (n = 1). Median DAP was 261 Gy * cm2 (range 29-950), median AK was 0.2 Gy (range 0.05-0.5), and median FT was 28.2 min (range 7.7-93.7). Mean portosystemic pressure gradient decreased from 16.8  ±  5.1 mmHg to 7.5  ±  3.3 mmHg (P <  0.01). There were no major procedural complications. Overall clinical success was achieved in 77% of patients (mean follow-up of 21.1 months). Encephalopathy was observed in 16 patients (34%), grade II-III encephalopathy in 7 patients (15%). TIPS revision was performed in 15 patients (32%). Overall survival rate was 75%. CONCLUSION: In our experience, the use of real-time ultrasound guidance allowed the majority of the TIPS to be performed via a transjugular approach alone with a reasonably low radiation exposure considering the high technical difficulties of the selected cohort of patients with CVPT or PC.

Case of primary hepatic leiomyosarcoma successfully treated with laparoscopic right hepatectomy.

We describe the case of a 77-year-old woman, presenting with non-specific epigastric pain. Physical examination and subsequent imaging revealed the presence of a large mass in the right liver lobe. This was shown to be a leiomyosarcoma on biopsy histology. Further investigation confirmed this to be a primary hepatic leiomyosarcoma with no evidence of metastases. The patient underwent successful surgical resection. She is currently under imaging follow-up, with no evidence of disease recurrence.

OCCUPATIONAL RADIATION DOSE PERFORMING HEPATOBILIARY MINIMALLY INVASIVE PROCEDURES IN CHILDREN WEIGHING LESS THAN 20 kg.

Our objective is to retrospectively evaluate the effective dose (E) of operators performing pediatric Hepatobiliary Minimally Invasive Procedures (HMIP). Between October 2015 and December 2017, 58 consecutive HMIP were performed on 26 children weighing less than 20 kg (mean 12.3 kg, median 13 kg, range 2.4-20 kg). About 31 vascular procedures (n = 9 hepatic venograms with/without stenting; n = 9 retrograde wedge portography; n = 8 transhepatic portography with angioplasty and/or stenting and n = 5 hepatic arteriography/embolization) and 27 non-vascular procedures (n = 6 percutaneous transhepatic biliary drainage (PTBD); n = 3 bilioplasty; n = 15 biliary catheter change and n = 3 cholangiogram) were performed. Electronic personal dosimeters were used to measure radiation doses to the interventional radiologist, radiographer and anesthesia nurse. The results shows the highest mean effective dose: interventional radiologist's in PTBD (1.18 µSv); radiographer's in hepatic veins phlebography with/without stenting (0.25 µSv) and nurse's in hepatic arteriography/embolization (0.26 µSv). Operators' E can vary depending on the complexity of procedure performed and the position of the operators within the angiosuite.

Imaging of hepatic hemangioma: from A to Z.

The hemangioma is the most common solid lesion of the liver. Therefore, radiologists must know the typical and atypical imaging findings of this lesion in order to reach a correct diagnosis and avoid diagnostic errors. However, only few papers have comprehensively described the entire spectrum of atypical and uncommon imaging features. In this updated review, we provide the imaging features of hepatic hemangioma, in both typical and atypical forms, as well as its association with abnormalities in the adjacent hepatic parenchyma and other hepatic lesions, and its complications.

Budd-Chiari Syndrome and hepatic regenerative nodules: Magnetic resonance findings with emphasis of hepatobiliary phase.

Budd-Chiari syndrome (BCS) is a disorder with numerous causes that is a result of hepatic outflow obstruction, in the absence of right heart failure or constrictive pericarditis. Acute Budd-Chiari syndrome is uncommon and clinically characterized by ascites, hepatomegaly, and hepatic insufficiency. In the majority of cases, patients present with chronic BCS, showing a dysmorphic liver disease with variable fibrosis deposition. In chronic Budd-Chiari syndrome, hepatocellular carcinoma (HCC) and benign regenerative nodules (called large regenerative nodules or FNH-like lesions) have been described in the literature. Very few studies have reported magnetic resonance imaging (MRI) findings about these nodules, using hepatobiliary contrast medium. The aim of our review is to describe the magnetic resonance imaging findings of hepatic regenerative nodules in BCS, with emphasis on the hepatobiliary phase, and to compare the imaging features of benign nodules with those of HCC.

Complications from percutaneous microwave ablation of liver tumours: a pictorial review.

Percutaneous microwave ablation of liver tumours is a well-established technique that has been proven to be effective in the curative and palliative treatment of small volume primary and secondary liver tumours. Microwave ablation is designed to achieve larger areas of necrosis compared to radiofrequency ablation and has a good safety profile among liver tumour treatments. Mortality is unreported and major complications are rare. Knowledge of potential complications is essential for interventional radiologists performing liver ablation in order to reduce patient morbidity. The aim of this review is to illustrate major complications post microwave ablation in a pictorial format as well as a discussion on how best to avoid these complications.

Magnetic resonance imaging of fibropolycystic liver disease: the spectrum of ductal plate malformations.

Fibropolycystic liver diseases, also known as ductal plate malformations, are a group of associated congenital disorders resulting from abnormal development of the biliary ductal system. These disorders include congenital hepatic fibrosis, biliary hamartomas, polycystic liver disease, choledochal cysts and Caroli disease. Recently, it has been thought to include biliary atresia in this group of diseases, because ductal plate malformations could be implicated in the pathogenesis of this disease. Concomitant associated renal anomalies can also be present, such as autosomal recessive polycystic kidney disease (ARPKD), medullary sponge kidney and nephronophthisis. These disorders can be clinically silent or can cause abnormalities such as cholangitis, portal hypertension, gastrointestinal bleeding and infections. The different types of ductal plate malformations show typical findings at magnetic resonance (MR) imaging. A clear knowledge of the embryology and pathogenesis of the ductal plate plays a pivotal role to understand the characteristic imaging appearances of these complex diseases. Awareness of these MR imaging findings is central to the detecting and differentiating between various fibropolycystic liver diseases and is important to direct appropriate clinical management and prevent misdiagnosis.

Multimodality imaging of the Meso-Rex bypass.

Extrahepatic portal vein obstruction (EHPVO) is the most common cause of upper gastrointestinal bleeding in children. It is defined as thrombosis of the extrahepatic portal vein with or without extension to the intrahepatic portal veins. The Meso-Rex shunt is the gold standard treatment in children with favorable anatomy since it restores physiological portal liver reperfusion. This is achieved by rerouting the splanchnic venous blood through an autologous graft from the superior mesenteric vein (SMV) into the Rex recess of the left portal vein, curing portal hypertension by doing so. General and hepatobiliary radiologists must be familiar with multimodality imaging appearances of EHPVO and with the role of imaging in identifying suitable candidates for Meso-Rex bypass surgery. Imaging might also detect complications of this procedure, some of which might be treated via interventional radiology.

Solitary fibrous tumour of the mesentery: a case report.

We present the case of a male with an asymptomatic abdominal mass, where imaging-guided biopsy confirmed the lesion as a solitary fibrous tumour arising from the mesentery. This is a notably rare location for solitary fibrous tumours with only a few reported cases in the literature.

Small bowel imaging in Crohn's disease patients.

Crohn's disease (CD) is a lifelong, chronic inflammatory bowel disorder. The small bowel (SB) is involved to varying extents, and the clinical course may vary from an inflammatory type to a more complicated one with stricture, fistula, and abscess formation. Esophagogastroduodenoscopy and ileocolonoscopy with biopsies are the conventional endoscopic techniques that usually establish the diagnosis. On the other hand, CD may affect SB segments that cannot be reached through these procedures. Video capsule endoscopy and enteroscopy are additional endoscopic techniques that may allow further SB evaluation in such circumstances. Computed tomographic enterography, magnetic resonance enterography, and ultrasonography are radiologic techniques that serve as a crucial adjunct to endoscopic assessment. They enable the assessment of parts of the bowel that may be difficult to reach with conventional endoscopy; this allows for the detection of active inflammation, penetrating or stricturing disease, and the appreciation of extraintestinal complications. Both endoscopic and radiologic modalities play a role in establishing the diagnosis of CD, as well as determining the disease extent, activity and response to therapy. This review is intended to evaluate these modalities in terms of specificity, sensitivity, potential side-effects, and limiting factors. This should serve as a guide to the clinician for establishing the most appropriate and reliable test within a particular clinical context.

Unusual site for primary arterio-enteric fistula resulting in massive upper gastrointestinal bleeding - A case report on presentation and management.

INTRODUCTION: Communications between an artery and the bowel are termed arterio-enteric fistulae. These are uncommon and mainly involve the aorta and duodenum. They can cause fatal haemorrhage. A primary aorto-enteric fistula has several aetiologies, one of which is post-radiotherapy. CASE REPORT: 75-year old gentleman presented with acute upper gastrointestinal bleeding and haemorrhagic shock. He had a past history of right colonic cancer treated by resection and radiotherapy. At emergency gastroscopy he became critically unstable and the procedure was unsuccessful to achieve haemostasis. After resuscitation, a CT angiogram confirmed a right ilio-duodenal fistula between the right common iliac artery and duodenum. Interventional radiology was performed and a covered stent was inserted in the right common iliac artery. The patient recovered and was subsequently discharged from hospital. Three months later, he presented once again with similar massive haematemesis. Despite all efforts to stabilise him, he passed away a few hours after this second admission. DISCUSSION: This case highlights what could possibly be a limitation of interventional radiology in providing definitive treatment for such a presentation. There are no set guidelines for the management of bleeding aorto-duodenal fistulae and literature is scarce. This makes it difficult to treat and the outcome is relatively unpredictable. CONCLUSION: While minimally invasive radiological techniques are invaluable in many areas and life-saving in countless emergency bleeds, cases like these should ideally not be treated by stenting alone. It would be wise to follow arterio-enteric fisula bleeds by definitive open surgical repair.

Radiation Doses to Operators in Hepatobiliary Interventional Procedures.

PURPOSE: The primary aim of this study is to provide a summary of operators' radiation doses during hepatobiliary fluoroscopic guided procedures. In addition, patient dose in these procedures was also documented. MATERIALS AND METHODS: A total of 283 transarterial chemoembolisation (TACE) and 302 biliary procedures, including 52 percutaneous transhepatic cholangiogram (PTC), 36 bilioplasty and 214 biliary catheter changes (BCC) performed over 14 months, were included. Electronic personal dosimeters were used to measure operator radiation doses. Effective dose (E) was calculated using modified Niklason algorithm. Patient dose was measured as dose area product (DAP) and fluoroscopy time (FT). RESULTS: For TACE, E for radiologist ranged between 0 and 9.96 µSv, for radiographer 0-0.99 µSv and for nurse 0-4.65 µSv. The patient DAP and FT ranged between 1.5 and 421.9 Gy cm2 and 1.91-67.25 min. For PTC, E for the radiologist ranged between 0.33 and 55.89 µSv, for radiographer 0-38.61 µSv and for nurse 0-3.18 µSv. Patient DAP and FT ranged between 1.7 and 218.4 Gy cm2 and 2.07-71.53 min. For bilioplasty, E ranged between 0.09 and 9.24 µSv for radiologist, 0-0.84 µSv for radiographer and 0-1.38 µSv for nurse. The patients' DAP and FT ranged from 0.7 to 52.54 Gy cm2 and 1.13-24.47 min. For BCC, E ranged from 0 to 12.78 µSv for radiologist, 0-8.43 µSv for radiographer and 0-4.05 µSv for nurse. Patient DAP and FT ranged between 0.12 and 117.3 Gy cm2 and 0.57-15.83 min. CONCLUSIONS: This study shows that doses to all operators performing hepatobiliary interventional procedures can be very low.

Hepatic morphology abnormalities: beyond cirrhosis.

The diagnosis of cirrhosis can be reached on the basis of established hepatic morphological changes. However, some other conditions can mimic cirrhosis. The aim of this pictorial essay is to review the CT and MRI appearances of hepatic morphology abnormalities in the cirrhotic liver and other diseases, describing pathologic conditions that can mimic cirrhosis, with useful tips for the differential diagnosis. Mimickers of cirrhosis include congenital hepatic fibrosis, Caroli disease, Budd-Chiari Syndrome, hepatoportal sclerosis, cavernous transformation of the portal vein, pseudocirrhosis from metastatic disease, acute liver failure, post-therapeutic morphologic changes in the liver, and infective conditions including schistosomiasis and oriental cholangiohepatitis. Recognizing the hepatic morphological changes in images can help radiologists to diagnose cirrhosis and other diseases in early stages.