Controlled flow reduction of an iliacoportal shunt graft for portal vein arterialization in a pediatric patient.

Portal vein arterialization is a rarely used, temporary surgical salvage solution to prevent biliary and hepatic ischemia and necrosis in acute liver de-arterialization. However, it can induce portal hypertension, causing increased morbidity and mortality. We report the case of a 5-year-old girl with portal hypertension and right ventricle volume overload following the creation of an iliacoportal shunt graft for portal vein arterialization due to vessel-adhering neuroblastoma. Partial shunt graft closure was accomplished by placing a stent graft in an hourglass configuration via the right femoral artery using two slender-sheaths in a line with the second more distal than the first. Subsequently, the patient's symptoms of right ventricle volume overload and portal hypertension decreased. In conclusion, endovascular reduction of elevated portal blood flow after portal vein arterialization is feasible, even in pediatric patients.

Structured magnetic resonance imaging-based characterization of the marginal vein reveals limits of the Weber-classification.

Background: The marginal vein (MV) is a persisting embryonic vein located at the lateral aspect of the lower limb. The Weber-classification, which was developed on the basis of phlebography in the 1990s, is the only existing classification system for this rare disease. Aim of this study was the structured characterization of the lateral marginal vein (MV) using magnetic resonance imaging (MRI) and evaluation of the applicability of the Weber-classification. Patients and methods: Institutional Review Board approval was obtained for this retrospective, single-center study. All patients who underwent contrast-enhanced MRI (using a prospectively determined protocol) of the untreated MV were included. MV anatomy and associated findings were characterized in a structured way taking into account the criteria of the Weber-classification for MV: inflow, outflow and extension. If three criteria of the Weber-classification were fulfilled the MV was categorized as "classifiable according to Weber". The MV was categorized as "partially classifiable according to Weber", if two criteria were met and as "not classifiable according to Weber" if less than two criteria were applicable. Results: 56 imaging studies of 58 MV (7 thoracoabdominal, 51 lower extremities) were reviewed. 18/51 MV of the lower extremities were "classifiable" according to the Weber-classification. 33/51 lower extremity MV were not definitely categorized according to the Weber-classification: 19/51 MV were "partially classifiable" and 14/51 MV were "not classifiable". 30/51 MV presented with hypoplastic, 1/51 with aplastic deep venous system. 34/51 lower extremity and 6/7 thoracoabdominal MV were associated with an additional vascular malformation (VM). Conclusions: MRI is suitable for detailed anatomic characterization of the MV and reveals additional therapy relevant findings like associated VM. The Weber-classification was not applicable in most cases, reflecting its limits and the heterogeneity of this rare disease. Structured reports rather than an obsolete classification system should be preferred for MRI of the MV.

Additive value of transarterial embolization to systemic sirolimus treatment in kaposiform hemangioendothelioma.

Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor in children, which can be accompanied by life-threatening thrombocytopenia, referred to as Kasabach-Merritt phenomenon (KMP). The mTOR inhibitor sirolimus is emerging as targeted therapy in KHE. As the sirolimus effect on KHE occurs only after several weeks, we aimed to evaluate whether additional transarterial embolization is of benefit for children with KHE and KMP. Seventeen patients with KHE and KMP acquired from 11 hospitals in Germany were retrospectively divided into two cohorts. Children being treated with adjunct transarterial embolization and systemic sirolimus, and those being treated with sirolimus without additional embolization. Bleeding grade as defined by WHO was determined for all patients. Response of the primary tumor at 6 and 12 months assessed by magnetic resonance imaging (MRI), time to response of KMP defined as thrombocyte increase >150 × 103 /µL, as well as rebound rates of both after cessation of sirolimus were compared. N = 8 patients had undergone additive embolization to systemic sirolimus therapy, sirolimus in this group was started after a mean of 6.5 ± 3 days following embolization. N = 9 patients were identified who had received sirolimus without additional embolization. Adjunct embolization induced a more rapid resolution of KMP within a median of 7 days vs 3 months; however, tumor response as well as rebound rates were similar between both groups. Additive embolization may be of value for a more rapid rescue of consumptive coagulopathy in children with KHE and KMP compared to systemic sirolimus only.

Fluoroscopy-guided endoscopic sclerotherapy: a novel hybrid approach for symptomatic rectosigmoidal venous malformation (with video).

BACKGROUND AND AIMS: Recommendations for the treatment of lower GI bleeding do not include bleeding from venous malformations (VMs). The aim of this study was to delineate the usefulness of a novel hybrid intervention (fluoroscopy-guided endoscopic sclerotherapy) for the treatment of symptomatic VMs in the rectosigmoidal colon with bleeding. METHODS: The magnetic resonance images of 421 patients with VM, referred to multicenter vascular anomaly centers from 2009 to 2017, were analyzed retrospectively. Treatment was performed for all patients who experienced bleeding from rectosigmoidal VMs using fluoroscopy-guided endoscopic sclerotherapy with polidocanol foam as a novel approach. RESULTS: A total of 27 patients displayed VM in the rectosigmoidal area. Eleven of these presented with acute or previous bleeding and received treatment. Active bleeding was observed in 8 patients (72.7%), whereas 3 patients (27.3%) had signs of previous bleeding. Six of the 11 patients had anemia (54.5%). There were no adverse events within 24 hours of the intervention. In a 2-year follow-up period, only 1 patient (9.1%) presented with recurrent bleeding after 13 months and was successfully treated again with fluoroscopy-guided endoscopic sclerotherapy. CONCLUSIONS: Fluoroscopy-guided endoscopic sclerotherapy was shown to be a safe and effective treatment of symptomatic VMs of the rectosigmoidal area. Thus, fluoroscopy-guided endoscopic sclerotherapy should be considered for patients with bleeding from VMs of the rectosigmoid after a comprehensive workup and interdisciplinary case discussion.

Congenital Disseminated Pyogenic Granuloma: Characterization of an Aggressive Multisystemic Disorder.

OBJECTIVE: To describe the clinical, radiologic, and histopathologic features of "congenital disseminated pyogenic granuloma" involving various organs with high morbidity related to cerebral hemorrhagic involvement. STUDY DESIGN: We searched the database of the Vascular Anomalies Center at Boston Children's Hospital from 1999 to 2019 for patients diagnosed as having multiple vascular lesions, visceral vascular tumors, congenital hemangiomatosis, multiple pyogenic granulomas, or multiple vascular lesions without a definite diagnosis. A retrospective review of the medical records, photographs, histopathologic, and imaging studies was performed. Only patients with imaging studies and histopathologic diagnosis of pyogenic granuloma were included. RESULTS: Eight children (5 male, 3 female) had congenital multifocal cutaneous vascular tumors. Lesions also were found in the brain (n = 7), liver (n = 4), spleen (n = 3), muscles (n = 4), bone (n = 3), retroperitoneum (n = 3), and intestine/mesentery (n = 2). Less commonly affected were the spinal cord, lungs, kidneys, pancreas, and adrenal gland (n = 1 each). The mean follow-up period was 21.8 months. The cerebral and visceral lesions were hemorrhagic with severe neurologic sequelae. The histopathologic diagnosis was pyogenic granuloma with prominent areas of hemorrhage and necrosis. The endothelial cells had enlarged nuclei, pale cytoplasm and were immunopositive for CD31 and negative for D2-40 and glucose transporter 1. CONCLUSIONS: Congenital disseminated pyogenic granuloma is a distinct multisystemic aggressive disorder that primarily affects the skin, brain, visceral organs, and musculoskeletal system. Differentiation of this entity from other multiple cutaneous vascular lesions is critical because of possible cerebral hemorrhagic involvement.

[Diagnostic Criteria and Treatment of Hereditary Hemorrhagic Telangiectasia]. / Diagnostik und Behandlung der hereditären hämorrhagischen Teleangiektasie.

Hereditary hemorrhagic telangiectasia (HHT; Osler-Weber-Rendu syndrome; Morbus Osler) represents a syndrome affecting capillary vessels, leading to arteriovenous shunting. With an average worldwide prevalence of 1:5.000-8.000 HHT is considered an orphan disease. Arteriovenous shunts involve predominantly the nasal mucosa, the intestine, lung, liver and central nervous system. Epistaxis is the primary and most bothersome complaint of patients with HHT. A multistage therapeutic concept includes nasal ointment, laser therapy under local anesthesia and surgery under general anesthesia, as well as drug therapies. In addition, screening to determine affection of internal organs is carried out. Lesions that require therapy should be treated in an interdisciplinary setting. Treatment of lesions of the skin, oral and gastrointestinal mucosa and liver is carried out in regard to patients' symptoms, whereas vascular malformations of the lung and brain might need treatment without being symptomatic, due to possible life-threatening complications.

Venous Malformations: Phleboliths Correlate With the Presence of Arteriovenous Microshunts.

OBJECTIVE: The objective of this study was to identify differences between venous malformations (VMs) with arteriovenous (AV) microshunts and VMs without AV microshunts. MATERIALS AND METHODS: In this retrospective study, 83 patients with untreated VMs of the extremities underwent a prospectively defined MRI protocol performed at 3 T. MR images were reviewed to determine localization and extent of each VM and tissue involvement. The VM volume and the lesion volume relative to body surface were measured. The number of phleboliths within the lesions was determined. Using time-resolved MR angiography, the hemodynamic subtype (VM with AV microshunts versus VM without AV microshunts) was classified, and the interval between the onset of arterial enhancement and lesion enhancement (tonset) was measured. Clinical data were reviewed to determine patient demographic characteristics, the onset of symptoms, the frequency of thrombophlebitis, and the pain score. RESULTS: Of the 83 patients, 56 (67%) presented with AV microshunts. The tonset (p ≤ 0.001), absolute and relative lesion volume (p = 0.001), and number of phleboliths (p = 0.038) differed significantly between these two subgroups. With use of a multivariable regression model, the strongest indicator for VM with AV microshunts was the presence of more than two phleboliths (odds ratio, 2.80; p = 0.007). No differences were noted regarding patient demographic characteristics and history or lesion morphologic features or anatomy. CONCLUSION: Occurrence of AV microshunts in untreated VM is a frequent phenomenon. This hemodynamic subtype is significantly associated with phleboliths and large lesions. The subtypes did not differ in terms of history and clinical course.

[Management of Visceral Artery Aneurysms with Preservation of Organ Perfusion: More Than Twenty Years Experience]. / Management von Viszeralarterienaneurysmen unter besonderer Berücksichtigung der Organperfusion ­ Erfahrungen über mehr als 20 Jahre.

BACKGROUND: Visceral artery aneurysms (VAA) are rare and often incidental findings. Indications for treatment are symptomatic patients, pseudoaneurysms and a true aneurysm of diameter of ≥ 2.5 cm for mesenteric arteries and ≥ 3 cm for renal artery aneurysms. Pregnancy and liver transplantation play an important role in aneurysm rupture. Technical success after open or endovascular procedure and maintenance of organ perfusion are crucial. The aim of this review is to evaluate our data and experience of more than 20 years and to develop a strategy to deal with visceral artery aneurysm in elective and emergency cases. PATIENTS: Between 1995 and 2018, 179 patients (84 males, 95 females, median age 62 [18 - 87] years) were diagnosed with VAA at the Regensburg University Hospital. The site of aneurysm was the splenic artery in 113 (63%) patients (pts), hepatic and renal arteries in 22 and 21 pts (12% each), and gastropancreaticoduodenal artery in 14 (8%) and superior/inferior mesenteric artery in 9 (5%) cases. Surveillance without intervention occurred in 110 (62%) pts, and 34 (19%) pts underwent open and 35 (19%) endovascular repair. In all patients, preoperative imaging was performed, preferably by computed tomography angiography (CTA). RESULTS: A total of 69 patients underwent open or endovascular repair. 51 (74%) pts were treated electively, 18 (26%) pts presented urgently with acute bleeding. 16 emergency pts received endovascular treatment, and in 2 pts open surgery was performed. After emergency treatment, two pts exhibited segmental liver malperfusion without consequences. In one case, segmental bowel resection was necessary. 32/51 (63%) patients were treated electively by open surgery, 19/51 (37%) by endovascular procedures. There were no liver or bowel infarctions. Four splenectomies and one unilateral nephrectomy were necessary in patients with splenic or renal artery aneurysms. Moreover, three partial renal infarctions were noticed postoperatively (overall 8/21 [38%]). After endovascular repair of splenic or renal artery aneurysms, two cases of splenic and three cases of renal segmental infarction were observed. Splenectomy had to be performed twice (overall 7/14 [50%]). Organ perfusion was monitored by CTA, and preferentially by contrast enhanced ultrasound. CONCLUSION: The endovascular approach is the preferred option in an emergency to control bleeding in pseudoaneurysms. Patients for elective splenic or renal artery aneurysm repair have to be evaluated very carefully to achieve technical success with occlusion of the aneurysm and excellent organ perfusion. Imaging techniques such as ultrasound, especially CEUS, are strongly recommended in postoperative follow-up. Partial or complete splenic infarction leads to vaccination.

Time-resolved magnetic resonance angiography (MRA) at 3.0 Tesla for evaluation of hemodynamic characteristics of vascular malformations: description of distinct subgroups.

OBJECTIVES: Quantitative evaluation of hemodynamic characteristics of arteriovenous and venous malformations using time-resolved magnetic resonance angiography (MRA) at 3.0 Tesla. METHODS: Time-resolved MRA with interleaved stochastic trajectories (TWIST) at 3.0 Tesla was studied in 83 consecutive patients with venous malformations (VM) and arteriovenous malformations (AVM). Enhancement characteristics were calculated as percentage increase of signal intensity above baseline over time. Maximum percentage signal intensity increase (signalmax), time intervals between onset of arterial enhancement and lesion enhancement (tonset), and time intervals between beginning of lesion enhancement and maximum percentage of lesion enhancement (tmax) were analyzed. RESULTS: All AVMs showed a high-flow hemodynamic pattern. Two significantly different (p < 0.001) types of venous malformations emerged: VMs with arteriovenous fistulas (AVF) (median signalmax 737 %, IQR [interquartile range] = 511 - 1182 %; median tonset 5 s, IQR = 5 - 10 s; median tmax 35 s, IQR = 26 - 40 s) and without AVFs (median signalmax 284 %, IQR = 177-432 %; median tonset 23 s, IQR = 15 - 30 s; median tmax 60 s, IQR = 55 - 75 s). CONCLUSIONS: Quantitative evaluation of time-resolved MRA at 3.0 Tesla provides hemodynamic characterization of vascular malformations. VMs can be subclassified into two hemodynamic subgroups due to presence or absence of AVFs. KEY POINTS: • Time-resolved MRA at 3.0 Tesla provides quantitative hemodynamic characterization of vascular malformations. • Malformations significantly differ in time courses of enhancement and signal intensity increase. • AVMs show a distinctive high-flow hemodynamic pattern. • Two significantly different types of VMs emerged: VMs with and without AVFs.

Ethanolgel sclerotherapy of venous malformations improves health-related quality-of-life in adults and children - results of a prospective study.

OBJECTIVES: To assess the treatment-induced changes of health-related quality-of-life (HRQoL) in patients with venous malformations (VM) who underwent ethanol gel sclerotherapy. METHODS: The prospective study in children and adults was approved by the local ethics committee. 31 patients (mean age 23.42 years, range 6.6 - 46.5; 26 female, 5 male) with VM were included. Patients' self-assessed HRQoL was measured before and after treatment using psychometrically validated questionnaires for adults and children. Differences were analysed with a paired t test. RESULTS: 58 sclerotherapy sessions were performed. The Physical Component Summary (PCS) at baseline was 43.69 and increased significantly (p = 0.01122) to 48.95 after treatment. The bodily pain (BP) scale increased significantly from 37.94 to 48.56 (p = 0.00002), the general health (GH) scale increased significantly from 46.69 to 52.17 (p = 0.00609). Baseline Physical Summary Score (PHS) in children increased significantly after treatment (p < 0.00001) from 25.25 to 45.89. The baseline Psychosocial Summary Score (PSS) in children was 51.08 and increased significantly (p = 0.00031) after treatment to 58.84. CONCLUSION: Paediatric and adult patients with VM suffer from bodily pain with overall reduced physical functioning. After sclerotherapy, these restrictions are successfully returning to normal levels with a positive effect on mental and psychosocial domains. KEY POINTS: • Sclerotherapy in venous malformation patients has an unknown effect on health-related quality-of-life • Prospective study showed improvements in bodily pain and general health in adults • Children and adults improved from treatment with ethanol gel • Sclerotherapy is an appropriate therapy.

Ethanol-Gel Sclerotherapy of Venous Malformations: Effectiveness and Safety.

OBJECTIVE: In the treatment of venous malformations, ethanol may be administered in a gelified form to increase local effects and reduce systemic ones. The purpose of this prospective study was to evaluate the efficacy and safety of a commercially available viscous ethanol gel in the treatment of venous malformations. SUBJECTS AND METHODS: Thirty-one patients (mean age, 23.4 years; age range, 6.6-46.5 years) with venous malformations were prospectively scheduled for two ethanol-gel sclerotherapy sessions. Venous malformations were located at the lower extremity (n = 18), the upper extremity (n = 9), and the face (n = 4). Questionnaires to assess pain, clinical examinations, professional photographs, and contrast-enhanced MRI of the venous malformations were performed before and after therapy to measure therapy-induced changes. Two experienced radiologists blinded to the examination date and clinical status compared photographs and MR images before and after treatment. RESULTS: A mean of 4.2 mL of ethanol gel were administered per session. The technical success rate was 100%. Clinical success, defined as improvement or resolution of symptoms, was noted in 81% of patients. Mean pain score decreased, and the difference was statistically significant (3.9 vs 3.1, p = 0.005). In 54 treatment sessions where follow-up was available, four minor complications occurred. Comparison of photographs and MR images before and after treatment showed improvement in 35% and 93% of patients, respectively. CONCLUSION: Ethanol gel is an effective and safe sclerosing agent in the treatment of venous malformations.

CT features of early type II endoleaks after endovascular repair of abdominal aortic aneurysms help predict aneurysm sac enlargement.

PURPOSE: To determine computed tomographic (CT) features of early type II endoleaks associated with aneurysm sac enlargement after endovascular aortic aneurysm repair (EVAR) of abdominal aortic aneurysm. MATERIALS AND METHODS: Institutional review board approval was not required for this retrospective study. The authors reviewed imaging and clinical data from 56 patients (seven women, 49 men; mean age ± standard deviation, 71 years ± 7.9; age range, 52-85 years) with early type II endoleak who had undergone EVAR between December 2002 and December 2011 and who had been followed up with imaging and clinical evaluation for at least 6 months. The number and diameter of all feeding and/or draining arteries were measured, and endoleaks were classified according to their sources into simple inferior mesenteric artery (IMA), simple lumbar artery (LA), complex LA, and complex IMA-LA type II endoleaks. Volume and attenuation of the nidus were measured. Aneurysm enlargement was defined as an increase in the aneurysm volume of more than 5% during follow-up. Simple and multivariate logistic regression analyses were performed to identify independent clinical and imaging variables associated with aneurysm enlargement. RESULTS: Twenty-three of the 56 patients (41%) showed aneurysm sac enlargement during follow-up (mean follow-up, 3.0 years ± 2.0). With the multivariate model, the variables that showed the strongest indicators for aneurysm sac enlargement were complex IMA-LA type II endoleak (odds ratio [OR] = 10.29, P = .004) and the diameter of the largest feeding and/or draining artery (OR = 4.55, P = .013). Patients without complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 3.8 mm and patients with a complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 2.2 mm were at high risk for aneurysm sac enlargement. CONCLUSION: The strongest indicators for aneurysm sac enlargement are complex IMA-LA type II endoleak and the diameter of the largest feeding and/or draining artery.

Lymphatic and other vascular malformative/overgrowth disorders are caused by somatic mutations in PIK3CA.

OBJECTIVES: To test the hypothesis that somatic phosphatidylinositol-4,5-bisphospate 3-kinase, catalytic subunit alpha (PIK3CA) mutations would be found in patients with more common disorders including isolated lymphatic malformation (LM) and Klippel-Trenaunay syndrome (KTS). STUDY DESIGN: We used next generation sequencing, droplet digital polymerase chain reaction, and single molecule molecular inversion probes to search for somatic PIK3CA mutations in affected tissue from patients seen at Boston Children's Hospital who had an isolated LM (n = 17), KTS (n = 21), fibro-adipose vascular anomaly (n = 8), or congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (n = 33), the disorder for which we first identified somatic PIK3CA mutations. We also screened 5 of the more common PIK3CA mutations in a second cohort of patients with LM (n = 31) from Seattle Children's Hospital. RESULTS: Most individuals from Boston Children's Hospital who had isolated LM (16/17) or LM as part of a syndrome, such as KTS (19/21), fibro-adipose vascular anomaly (5/8), and congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (31/33) were somatic mosaic for PIK3CA mutations, with 5 specific PIK3CA mutations accounting for ∼ 80% of cases. Seventy-four percent of patients with LM from Seattle Children's Hospital also were somatic mosaic for 1 of 5 specific PIK3CA mutations. Many affected tissue specimens from both cohorts contained fewer than 10% mutant cells. CONCLUSIONS: Somatic PIK3CA mutations are the most common cause of isolated LMs and disorders in which LM is a component feature. Five PIK3CA mutations account for most cases. The search for causal mutations requires sampling of affected tissues and techniques that are capable of detecting low-level somatic mosaicism because the abundance of mutant cells in a malformed tissue can be low.

Intravenous Opioid Medication with Piritramide Reduces the Risk of Pneumothorax During CT-Guided Percutaneous Core Biopsy of the Lung.

PURPOSE: CT-guided percutaneous core biopsy of the lung is usually performed under local anesthesia, but can also be conducted under additional systemic opioid medication. The purpose of this retrospective study was to assess the effect of intravenous piritramide application on the pneumothorax rate and to identify risk factors for post-biopsy pneumothorax. MATERIALS AND METHODS: One hundred and seventy-one core biopsies of the lung were included in this retrospective single center study. The incidence of pneumothorax and chest tube placement was evaluated. Patient-, procedure- and target-related variables were analyzed by univariate and multivariable logistic regression analysis. RESULTS: The overall incidence of pneumothorax was 39.2% (67/171). The pneumothorax rate was 31.5% (29/92) in patients who received intravenous piritramide and 48.1% (38/79) in patients who did not receive piritramide. In multivariable logistic regression analysis periinterventional piritramide application proved to be the only independent factor to reduce the risk of pneumothorax (odds ratio 0.46, 95%-confidence interval 0.24, 0.88; p = 0.018). Two or more pleura passages (odds ratio 3.38, 95%-confidence interval: 1.15, 9.87; p = 0.026) and prone position of the patient (odds ratio 2.27, 95%-confidence interval: 1.04, 4.94; p = 0.039) were independent risk factors for a higher pneumothorax rate. CONCLUSION: Procedural opioid medication with piritramide proved to be a previously undisclosed factor decreasing the risk of pneumothorax associated with CT-guided percutaneous core biopsy of the lung. LEVEL OF EVIDENCE 4: small study cohort.

Percutaneous transcatheter aspiration of pulmonary embolism leading to diagnosis of hepatocellular carcinoma tumor embolus and change in systemic chemotherapy.

The management of metastatic hepatocellular carcinoma (HCC) is complex, particularly when complicated by pulmonary embolism. In these cases, atezolizumab-bevacizumab therapy is contraindicated due to an elevated risk of thromboembolic events. Differentiating pulmonary tumor embolism from thromboembolic disease is diagnostically challenging. This report outlines the benefit of transcatheter aspiration to obtain pathological evidence of pulmonary artery tumor embolus in an HCC patient. The intervention enabled a significant shift in the management strategy, leading to an escalation of systemic HCC therapy. This case underscores the importance of precise diagnostic techniques such as transcatheter aspiration in guiding treatment decisions, particularly in cases where pulmonary embolism may signify an underlying malignancy-driven process.

Deep learning-based differentiation of peripheral high-flow and low-flow vascular malformations in T2-weighted short tau inversion recovery MRI.

BACKGROUND: Differentiation of high-flow from low-flow vascular malformations (VMs) is crucial for therapeutic management of this orphan disease. OBJECTIVE: A convolutional neural network (CNN) was evaluated for differentiation of peripheral vascular malformations (VMs) on T2-weighted short tau inversion recovery (STIR) MRI. METHODS: 527 MRIs (386 low-flow and 141 high-flow VMs) were randomly divided into training, validation and test set for this single-center study. 1) Results of the CNN's diagnostic performance were compared with that of two expert and four junior radiologists. 2) The influence of CNN's prediction on the radiologists' performance and diagnostic certainty was evaluated. 3) Junior radiologists' performance after self-training was compared with that of the CNN. RESULTS: Compared with the expert radiologists the CNN achieved similar accuracy (92% vs. 97%, p = 0.11), sensitivity (80% vs. 93%, p = 0.16) and specificity (97% vs. 100%, p = 0.50). In comparison to the junior radiologists, the CNN had a higher specificity and accuracy (97% vs. 80%, p < 0.001; 92% vs. 77%, p < 0.001). CNN assistance had no significant influence on their diagnostic performance and certainty. After self-training, the junior radiologists' specificity and accuracy improved and were comparable to that of the CNN. CONCLUSIONS: Diagnostic performance of the CNN for differentiating high-flow from low-flow VM was comparable to that of expert radiologists. CNN did not significantly improve the simulated daily practice of junior radiologists, self-training was more effective.

The status of academic interventional radiologists in Germany with focus on gender disparity: how can we do better?

PURPOSE: The aim was to characterize the framework conditions in academic interventional radiology (IR) in Germany with focus on differences between genders. MATERIALS AND METHODS: After IRB approval, all members of The German Society for Interventional Radiology and Minimally Invasive Therapy (n = 1,632) were invited to an online survey on work and research. Statistical comparisons were undertaken with the Fisher's exact test, Wilcoxon rank sum test or Pearson's Chi-squared test. RESULTS: From 267 available questionnaires (general response rate 16.4%), 200 were fully completed. 40% of these (78/200) were involved in research (71% men vs. 29% women, p < 0.01) and eligible for further analysis. Of these, 6% worked part-time (2% vs. 17%, p < 0.05). 90% of the respondents spent less than 25% of their research during their paid working hours, and 41% performed more than 75% of their research during. leisure time. 28% received exemption for research. 88% were (rather) satisfied with their career. One in two participants successfully applied for funding, with higher success rates among male applicants (90% vs. 75%) and respondents with protected research time (93% vs. 80%). Compared to men, women rated their entrance in research as harder (p < 0.05), their research career as more important (p < 0.05), felt less noticed at congresses (93% vs. 53%, p < 0.01), less confident (98% vs. 71%, p < 0.01), and not well connected (77% vs. 36%, p < 0.01).  CONCLUSION: Women and men did research under the same circumstances; however, women were underrepresented. Future programs should generally focus on protected research time and gather female mentors to advance academic IR in Germany.

Extracranial Vascular Anomalies Driven by RAS/MAPK Variants: Spectrum and Genotype-Phenotype Correlations.

BACKGROUND: We aimed to correlate alterations in the rat sarcoma virus (RAS)/mitogen-activated protein kinase pathway in vascular anomalies to the clinical phenotype for improved patient and treatment stratification. METHODS AND RESULTS: This retrospective multicenter cohort study included 29 patients with extracranial vascular anomalies containing mosaic pathogenic variants (PVs) in genes of the RAS/mitogen-activated protein kinase pathway. Tissue samples were collected during invasive treatment or clinically indicated biopsies. PVs were detected by the targeted sequencing of panels of genes known to be associated with vascular anomalies, performed using DNA from affected tissue. Subgroup analyses were performed according to the affected genes with regard to phenotypic characteristics in a descriptive manner. Twenty-five vascular malformations, 3 vascular tumors, and 1 patient with both a vascular malformation and vascular tumor presented the following distribution of PVs in genes: Kirsten rat sarcoma viral oncogene (n=10), neuroblastoma ras viral oncogene homolog (n=1), Harvey rat sarcoma viral oncogene homolog (n=5), V-Raf murine sarcoma viral oncogene homolog B (n=8), and mitogen-activated protein kinase kinase 1 (n=5). Patients with RAS PVs had advanced disease stages according to the Schobinger classification (stage 3-4: RAS, 9/13 versus non-RAS, 3/11) and more frequent progression after treatment (RAS, 10/13 versus non-RAS, 2/11). Lesions with Kirsten rat sarcoma viral oncogene PVs infiltrated more tissue layers compared with the other PVs including other RAS PVs (multiple tissue layers: Kirsten rat sarcoma viral oncogene, 8/10 versus other PVs, 6/19). CONCLUSIONS: This comparison of patients with various PVs in genes of the RAS/MAPK pathway provides potential associations with certain morphological and clinical phenotypes. RAS variants were associated with more aggressive phenotypes, generating preliminary data and hypothesis for future larger studies.

Biliary Leak after Pediatric Liver Transplantation Treated by Percutaneous Transhepatic Biliary Drainage-A Case Series.

BACKGROUND: Biliary leaks are a severe complication after pediatric liver transplantation (pLT), and successful management is challenging. OBJECTIVES: The aim of this case series was to assess the outcome of percutaneous transhepatic biliary drainage (PTBD) in children with bile leaks following pLT. The necessity of additional percutaneous bilioma drainage and laboratory changes during therapy and follow-up was documented. MATERIAL AND METHODS: All children who underwent PTBD for biliary leak following pLT were included in this consecutive retrospective single-center study and analyzed regarding site of leak, management of additional bilioma, treatment response, and patient and transplant survival. The courses of inflammation, cholestasis parameters, and liver enzymes were retrospectively reviewed. RESULTS: Ten children underwent PTBD treatment for biliary leak after pLT. Seven patients presented with leakage at the hepaticojejunostomy, two with leakage at the choledocho-choledochostomy and one with a bile leak because of an overlooked segmental bile duct. In terms of the mean, the PTBD treatment started 40.3 ± 31.7 days after pLT. The mean duration of PTBD treatment was 109.7 ± 103.6 days. Additional percutaneous bilioma drainage was required in eight cases. Bile leak treatment was successful in all cases, and no complications occurred. The patient and transplant survival rate was 100%. CRP serum level, leukocyte count, gamma-glutamyl transferase (GGT), and total and direct bilirubin level decreased significantly during treatment with a very strong effect size. Additionally, the gamma-glutamyl transferase level showed a statistically significant reduction during follow-up. CONCLUSIONS: PTBD is a very successful strategy for bile leak therapy after pLT.