Radiomics and machine learning for renal tumor subtype assessment using multiphase computed tomography in a multicenter setting.

OBJECTIVES: To distinguish histological subtypes of renal tumors using radiomic features and machine learning (ML) based on multiphase computed tomography (CT). MATERIAL AND METHODS: Patients who underwent surgical treatment for renal tumors at two tertiary centers from 2012 to 2022 were included retrospectively. Preoperative arterial (corticomedullary) and venous (nephrogenic) phase CT scans from these centers, as well as from external imaging facilities, were manually segmented, and standardized radiomic features were extracted. Following preprocessing and addressing the class imbalance, a ML algorithm based on extreme gradient boosting trees (XGB) was employed to predict renal tumor subtypes using 10-fold cross-validation. The evaluation was conducted using the multiclass area under the receiver operating characteristic curve (AUC). Algorithms were trained on data from one center and independently tested on data from the other center. RESULTS: The training cohort comprised n = 297 patients (64.3% clear cell renal cell cancer [RCC], 13.5% papillary renal cell carcinoma (pRCC), 7.4% chromophobe RCC, 9.4% oncocytomas, and 5.4% angiomyolipomas (AML)), and the testing cohort n = 121 patients (56.2%/16.5%/3.3%/21.5%/2.5%). The XGB algorithm demonstrated a diagnostic performance of AUC = 0.81/0.64/0.8 for venous/arterial/combined contrast phase CT in the training cohort, and AUC = 0.75/0.67/0.75 in the independent testing cohort. In pairwise comparisons, the lowest diagnostic accuracy was evident for the identification of oncocytomas (AUC = 0.57-0.69), and the highest for the identification of AMLs (AUC = 0.9-0.94) CONCLUSION: Radiomic feature analyses can distinguish renal tumor subtypes on routinely acquired CTs, with oncocytomas being the hardest subtype to identify. CLINICAL RELEVANCE STATEMENT: Radiomic feature analyses yield robust results for renal tumor assessment on routine CTs. Although radiologists routinely rely on arterial phase CT for renal tumor assessment and operative planning, radiomic features derived from arterial phase did not improve the accuracy of renal tumor subtype identification in our cohort.

[Management of Injuries to the Parenchymal Abdominal Organs]. / Management von Verletzungen parenchymatöser Abdominalorgane.

The most common organs affected by abdominal trauma are the spleen and the liver, often in combination. Pancreatic injuries are rare. In the case of blunt abdominal trauma, which is much more common, a clinical and laboratory examination as well as sonography should be performed. In the initial assessment, the circulatory situation must be screened. If there is haemodynamic instability and presentation of free fluid, an emergency laparotomy is indicated. If the situation is stable or stabilised and a pathological sonography is present, it is essential to perform triphasic contrast enhanced computed tomography, which is also mandatory in polytraumatised patients. If a renal injury is suspected, a late venous phase should be attached. In addition to the classification of the injury, attention should be paid to possible vascular injury or active bleeding. In this case, angiography with the possibility of intervention should be performed. Endoscopic treatment is possible for injuries of the pancreatic duct. If the imaging does not reveal any intervention target and a circulation is stable, a conservative approach is possible with continuous monitoring using clinical, laboratory and sonographic controls. Most injuries can be successfully treated by non-operative management (NOM).There are various surgical options for treating the injury, such as local and resecting procedures. There is also the option of "damage control surgery" with acute bleeding control and second look. Complex surgical procedures should be performed at centres. Postoperative complications arise out of elective surgery.In the less common case of penetrating abdominal trauma, the actual extent of the injury cannot be estimated from the visible wound. Here again, the circulatory situation determines the next steps. An emergency laparotomy should be carried out in case of instability. If the condition is stable, further diagnostics should be performed using contrast enhanced computed tomography. If penetration through the peritoneum cannot be clearly excluded, diagnostic laparoscopy should be performed.

[Staging and Diagnostics of Rectal Cancer]. / Modalitäten des Stagings und der Diagnostik bei Rektumkarzinom.

The review titled "Staging and Diagnostics of Rectal Cancer" aims to provide insight to imaging techniques in patients with rectal cancer.Rectal cancer is among the most common malignancies, with one of the highest mortality rates worldwide. Timely diagnosis and therapy of this cancer therefore has important socio-economic implications.Radiological imaging plays a major role in the planning of subsequent therapy. Modern tomographic imaging is used not only for initial diagnosis, but also for staging.The individual role of different imaging techniques in diagnosis of rectal cancer will be explained in detail, and their function in general. Furthermore, we will present relevant radiological research related.The increasing role of MRI-based local staging will be presented in detail in this review. Defined diagnostic criteria, based on common recommendations, will be explained. We will show how MRI-based local staging can support the initial diagnosis and follow-up examinations in collaboration with other medical specialties in therapeutic planning. In particular, we describe how MRI is capable of substantially influencing the determination of surgical procedures in rectal cancer.

Causes of Hypoxemia in COVID-19 Acute Respiratory Distress Syndrome: A Combined Multiple Inert Gas Elimination Technique and Dual-energy Computed Tomography Study.

BACKGROUND: Despite the fervent scientific effort, a state-of-the art assessment of the different causes of hypoxemia (shunt, ventilation-perfusion mismatch, and diffusion limitation) in COVID-19 acute respiratory distress syndrome (ARDS) is currently lacking. In this study, the authors hypothesized a multifactorial genesis of hypoxemia and aimed to measure the relative contribution of each of the different mechanism and their relationship with the distribution of tissue and blood within the lung. METHODS: In this cross-sectional study, the authors prospectively enrolled 10 patients with COVID-19 ARDS who had been intubated for less than 7 days. The multiple inert gas elimination technique (MIGET) and a dual-energy computed tomography (DECT) were performed and quantitatively analyzed for both tissue and blood volume. Variables related to the respiratory mechanics and invasive hemodynamics (PiCCO [Getinge, Sweden]) were also recorded. RESULTS: The sample (51 ± 15 yr; Pao2/Fio2, 172 ± 86 mmHg) had a mortality of 50%. The MIGET showed a shunt of 25 ± 16% and a dead space of 53 ± 11%. Ventilation and perfusion were mismatched (LogSD, Q, 0.86 ± 0.33). Unexpectedly, evidence of diffusion limitation or postpulmonary shunting was also found. In the well aerated regions, the blood volume was in excess compared to the tissue, while the opposite happened in the atelectasis. Shunt was proportional to the blood volume of the atelectasis (R2 = 0.70, P = 0.003). V˙A/Q˙T mismatch was correlated with the blood volume of the poorly aerated tissue (R2 = 0.54, P = 0.016). The overperfusion coefficient was related to Pao2/Fio2 (R2 = 0.66, P = 0.002), excess tissue mass (R2 = 0.84, P < 0.001), and Etco2/Paco2 (R2 = 0.63, P = 0.004). CONCLUSIONS: These data support the hypothesis of a highly multifactorial genesis of hypoxemia. Moreover, recent evidence from post-mortem studies (i.e., opening of intrapulmonary bronchopulmonary anastomosis) may explain the findings regarding the postpulmonary shunting. The hyperperfusion might be related to the disease severity.

Visualization of deglutition and gastroesophageal reflux using real-time MRI: a standardized approach to image acquisition and assessment.

This study aims to develop a standardized algorithm for gastroesophageal image acquisition and diagnostic assessment using real-time MRI. Patients with GERD symptoms undergoing real-time MRI of the esophagus and esophagogastric junction between 2015 and 2018 were included. A 10 ml bolus of pineapple juice served as an oral contrast agent. Patients performed Valsalva maneuver to provoke reflux and hiatal hernia. Systematic MRI assessment included visual presence of achalasia, fundoplication failure in patients with previous surgical fundoplication, gastroesophageal reflux, and hiatal hernia. A total of 184 patients (n = 92 female [50%], mean age 52.7 ± 15.8 years) completed MRI studies without adverse events at a mean examination time of 15 min. Gastroesophageal reflux was evident in n = 117 (63.6%), hiatal hernia in n = 95 (52.5%), and achalasia in 4 patients (2.2%). Hiatal hernia was observed more frequently in patients with reflux at rest (n = 67 vs. n = 6, p < 0.01) and during Valsalva maneuver (n = 87 vs. n = 8, p < 0.01). Real-time MRI visualized a morphologic correlate for recurring GERD symptoms in 20/22 patients (90%) after fundoplication procedure. In a large-scale single-center cohort of patients with GERD symptoms undergoing real-time MRI, visual correlates for clinical symptoms were evident in most cases. The proposed assessment algorithm could aid in wider-spread utilization of real-time MRI and provides a comprehensive approach to this novel imaging modality.

Time to Deliver on Promises: The Role of ERBB2 Alterations as Treatment Options for Colorectal Cancer Patients in the Era of Precision Oncology.

Receptor tyrosine kinase erythroblastic oncogene B2 (ERBB2), also known as human epidermal growth factor receptor 2 (HER2), represents an oncogenic driver and has been effectively targeted in breast and gastric cancer. Recently, next-generation sequencing (NGS) discovered ERBB2 as a promising therapeutic target in metastatic colorectal cancer (mCRC), where it is altered in 3-5% of patients, but no therapies are currently approved for this use. Herein, we present the experience of a single center in diagnosing actionable genetic ERBB2 alterations using NGS and utilizing the latest therapeutic options. Between October 2019 and December 2022, a total of 107 patients with advanced CRC underwent molecular analysis, revealing actionable ERBB2 mutations in two patients and ERBB2 amplifications in two other patients. These findings correlated with immunohistochemical (IHC) staining. Of these four patients, two were treated with trastuzumab-deruxtecan (T-DXd). We present two exemplary cases of patients with actionable ERBB2 alterations to demonstrate the effectiveness of T-DXd in heavily pretreated ERBB2-positive mCRC patients and the need for early molecular profiling. To fully exploit the potential of this promising treatment, earlier molecular profiling and the initiation of targeted therapies are essential.

Management of Aortoesophageal Fistula in a Palliative Patient with Non-Small-Cell Lung Cancer: A Case Report.

INTRODUCTION: Aortoesophageal fistulas are a rare but life-threatening complication in patients with thoracic malignancies. CASE PRESENTATION: We describe a case of a 55-year-old female patient with metastatic non-small-cell lung cancer. Due to esophageal tumor compression, a fully covered self-expanding metal stent (fcSEMS) had been deployed in the esophagus several months before. The patient was subsequently admitted to the emergency department with massive hematemesis. Endoscopy suggested a fistula between the aorta and the esophagus proximal of the fcSEMS, which was confirmed by computed tomography and led to hemodynamical relevant upper gastrointestinal bleeding. A thoracic endovascular aortic repair was performed to stop the hemorrhage. After the successful intervention, the patient needed long-term antibiotic treatment, and the fcSEMS remained in place. Afterward, the patient continued palliative tumor therapy using pembrolizumab for further 5 months. The patient died 8 months after the initial admission to the emergency department. CONCLUSION: This is to the best of our knowledge the first case of a technically successful interventional therapy of an aortoesophageal fistula which did not only achieve hemostasis but also enabled the patient to continue tumor therapy to regain quality of life.

[Treatment recommendation and care in traumatic rupture of the spleen]. / Therapieempfehlung und Versorgung bei traumatischer Milzruptur.

The spleen is the most frequently affected organ in blunt abdominal trauma. Initial diagnostics include the physical examination, laboratory blood controls and ultrasound. Furthermore, a triphasic dynamic contrast-enhanced computed tomography (CT) scan is indicated. Apart from the imaging-based classification of the injury with consideration of vascular alterations and active bleeding, the hemodynamic condition of the patient is a crucial factor. For patients who are hemodynamically stable or can be stabilized, a nonoperative management with a minimum of 24 h of continuous monitoring, regular blood controls of the hemoglobin level as well as ultrasound follow-up should be given precedence. In cases of active bleeding or pathological vascular alterations, a radiological intervention in the sense of an embolization should be initiated. A hemodynamically unstable patient must immediately undergo surgical treatment, during which a spleen-preserving approach via splenorrhaphy should principally be favored over splenectomy. This also applies to patients where the intervention has failed. To prevent severe infections after splenectomy it is advised to vaccinate against Pneumococcus, Haemophilus influenzae type B and Meningococcus as well as the annual seasonal influenza vaccination according to the Standing Committee on Vaccination (STIKO) recommendations.

T1 mapping of the prostate using Single-Shot T1FLASH and MOLLI MRI Techniques: Comparison of artifact burden and image quality.

PURPOSE: To assess artifact burden and image quality of different MRI T1 mapping techniques of the prostate. METHODS: Participants with suspected prostate cancer (PCa) were prospectively enrolled from June-October 2022 and examined with multiparametric prostate MRI (mpMRI; 3 T scanner; T1wi, T2wi, DWI und DCE). T1 mapping was performed before and after administration of gadolinium-based contrast-agent (GBCA) using (i) a modified Look-Locker inversion (MOLLI) technique and (ii) a novel single-shot T1FLASH inversion recovery technique. T2wi, DWI, T1FLASH and MOLLI sequences were systematically examined regarding prevalence of artifacts and image quality using a 5-point Likert-Scale. RESULTS: A total of n = 100 patients were included (median age: 68 years). T1FLASH maps (pre-and post-GBCA) showed metal artifacts in 7% of cases and susceptibility artifacts in 1%. For MOLLI maps, pre-GBCA metal and susceptibility artifacts were documented in 6.5% of cases each. MOLLI maps post-GBCA showed artifacts in 59% of cases resulting primarily from urinary GBCA excretion and GBCA accumulation at the bladder base (p < 0.01 versus T1FLASH post-GBCA). Image quality for T1FLASH pre-GBCA was rated at a mean 4.9+/-0.4 and for MOLLI at 4.8+/-0.6 (p = 0.14). Post-GBCA image quality was rated at a mean 4.9+/-0.4 for T1FLASH and at 3.7+/-1.1 for MOLLI (p < 0.001). CONCLUSIONS: T1FLASH maps provide a fast and robust method for quantification of T1 relaxation times of the prostate. T1FLASH is suitable for T1 mapping of the prostate following administration of contrast agents, while MOLLI T1 mapping is impaired through GBCA accumulation at the bladder base leading to severe image artifacts and reduced image quality.

[Metastasis or sarcoidosis - a diagnostic pitfall in metastatic rectal carcinoma]. / Metastase oder Sarkoidose ­ eine diagnostische Herausforderung beim metastasierten Rektumkarzinom.

BACKGROUND: Granulomatous diseases as sarcoidosis can impair the staging of metastatic diseases since metastasis are hard to distinguish from granulomas in standard imaging. This case report describes the diagnostic workup and therapy in a patient with simultaneous sarcoidosis and rectal cancer with hepatic metastasis and how a curative stadium was achieved. CASE DESCRIPTION: A 71-year old male patient was diagnosed with an adenocarcinoma of the rectum after presenting with involuntary weight loss and anemia. Further diagnostics raised strong suspicion of hepatic, pulmonary and splenic metastasis. Histology after bronchoscopy surprisingly discovered non-caseating granulomas, leading to the diagnosis of sarcoidosis. Due to an obstructive tumor, a rectum resection was performed. Due to a high suspicion of splenic metastasis during surgery, the spleen was removed. Histology revealed no metastasis in the spleen but multiple granulomas due to sarcoidosis. After surgery, biopsy of a suspicious lesion in the liver revealed both metastasis and sarcoidosis in the same sample. The patient was treated with a pseudo(neo)adjuvant chemotherapy with 5-Fluorouracil, Leukovorin, Oxaliplatin (FOLFOX) and Panitumumab (Anti-EGF-antibody). After treatment, CT scan revealed two hepatic lesions decreasing in size, while all other lesions were metrically stable. A right hemihepatectomy followed and histology revealed both sarcoidosis and metastasis. The curated patient was sent to aftercare and there is no suspicion for a relapse (13 month after last surgery). DISCUSSION: The simultaneous appearance of metastatic tumors and sarcoidosis creates a diagnostic dilemma since both manifestations can barely be distinguished in regular imaging technologies. This case report demonstrates that the histological work-up of affected organs with consecutive resections can cure a patient of a metastatic tumor disease, even in the context of simultaneous sarcoidosis.

Dual-Positive MPO- and PR3-ANCA-Associated Vasculitis Following SARS-CoV-2 mRNA Booster Vaccination: A Case Report and Systematic Review.

As the coronavirus disease 2019 (COVID-19) pandemic is ongoing, and new variants of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) are emerging, vaccines are needed to protect individuals at high risk of complications and to potentially control disease outbreaks by herd immunity. After SARS-CoV-2 vaccination, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) presenting with a pulmonary hemorrhage has been described. Previous studies suggested that monocytes upregulate major histocompatibility complex (MHC) II cell surface receptor human leukocyte antigen receptor (HLA-DR) molecules in granulomatosis with polyangiitis (GPA) patients with proteinase 3 (PR3)- and myeloperoxidase (MPO)-ANCA seropositivity. Here, we present a case of new-onset AAV after booster vaccination with the Pfizer-BioNTech SARS-CoV-2 mRNA vaccine. Moreover, we provide evidence that the majority of monocytes express HLA-DR in AAV after SARS-CoV-2 booster vaccination. It is possible that the enhanced immune response after booster vaccination and presence of HLA-DR+ monocytes could be responsible for triggering the production of the observed MPO- and PR3-ANCA autoantibodies. Additionally, we conducted a systematic review of de novo AAV after SARS-CoV-2 vaccination describing their clinical manifestations in temporal association with SARS-CoV-2 vaccination, ANCA subtype, and treatment regimens. In light of a hundred million individuals being booster vaccinated for SARS-CoV-2 worldwide, a potential causal association with AAV may result in a considerable subset of cases with potential severe complications.

Kinetics of human leukocyte antigen receptor HLA-DR+ monocytes and T lymphocytes during remission induction therapy in ANCA-associated vasculitis.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized by small vessel inflammation and the presence of autoantibodies against cytoplasmic proteases, most often proteinase-3 and myeloperoxidase. Peripheral blood monocytes are an important source of local macrophage accumulation within parenchymal organs, as evidenced by their presence in early lesions in ANCA-associated glomerulonephritis. Major histocompatibility complex (MHC) II cell surface receptor human leukocyte antigen receptor (HLA-DR) allows antigen presentation to T cells and is crucial for the initiation of an immune response. We herein report HLA-DR abundance in AAV and the kinetics of HLA-DR+ monocytes and T lymphocytes during remission induction therapy in AAV. Life-threatening AAV with pulmonary hemorrhage and renal involvement was associated with the presence of HLA-DR in a considerable population of peripheral blood monocytes and T lymphocytes, and relapsing disease manifested despite persistent B cell depletion after remission induction with rituximab. Moreover, remission induction in AAV with steroids, plasma exchange and intravenous cyclophosphamide, and improvement of clinical symptoms were associated with a decrease in HLA-DR+ differing between monocytes and T lymphocytes. Particularly, persistent suppression of HLA-DR+ monocytes was observed during remission induction, while an initial decrease in HLA-DR+ T lymphocytes was followed by recovery of this population during the further course. Detailed insights into HLA-DR kinetics could pave the way towards an increased understanding of immunopathology and identify patients that could mostly benefit from distinct remission induction regimens.

Assessment of esophagogastric junction morphology by dynamic real-time MRI: comparison of imaging features to high-resolution manometry.

PURPOSE: To assess the esophagogastric junction (EGJ) on real-time MRI and compare imaging parameters to EGJ morphology on high-resolution manometry (HRM). METHODS: A total of 105 of 117 eligible patients who underwent real-time MRI and high-resolution manometry for GERD-like symptoms between 2015 and 2018 at a single center were retrospectively evaluated (male n = 57; female n = 48; mean age 52.5 ± 15.4 years). Real-time MRI was performed at a median investigation time of 15 min (1 frame/40 ms). On HRM, EGJ morphology was assessed according to the Chicago classification of esophageal motility disorders. Real-time MRI was performed at 3 T using highly undersampled radial fast low-angle shot acquisitions with NLINV image reconstruction. A 10 mL pineapple juice bolus served as oral contrast agent at supine position. Real-time MRI films of the EGJ were acquired during swallowing events and during Valsalva maneuver. Anatomic and functional MRI parameters were compared to EGJ morphology on HRM. RESULTS: On HRM, n = 42 patients presented with EGJ type I (40.0%), n = 33 with EGJ type II (31.4%), and n = 30 with EGJ type III (28.6%). On real-time MRI, hiatal hernia was more common in patients with EGJ type III (66.7%) than in patients with EGJ type I (26.2%) and EGJ type II (30.3%; p < 0.001). Sliding hiatal hernia was more frequent in patients with EGJ type II (33.3%) than in patients with EGJ type III (16.7%) and EGJ type I (7.1%; p = 0.017). The mean esophagus-fundus angle of patients was 85 ± 31° at rest and increased to 101 ± 36° during Valsalva maneuver. CONCLUSION: Real-time MRI is a non-invasive imaging method for assessment of the esophagogastric junction. Real-time MRI can visualize dynamic changes of the EGJ during swallowing events.

Phantom study for comparison between computed tomography- and C-Arm computed tomography-guided puncture applied by residents in radiology. / Phantomstudie zum Vergleich zwischen Computertomografie- und C-Arm-Computertomografie-gesteuertem Punktionsverfahren bei Anwendung durch Weiterbildungsassistenten in der Radiologie.

PURPOSE: Comparison of puncture deviation and puncture duration between computed tomography (CT)- and C-arm CT (CACT)-guided puncture performed by residents in training (RiT). METHODS: In a cohort of 25 RiTs enrolled in a research training program either CT- or CACT-guided puncture was performed on a phantom. Prior to the experiments, the RiT's level of training, experience playing a musical instrument, video games, and ball sports, and self-assessed manual skills and spatial skills were recorded. Each RiT performed two punctures. The first puncture was performed with a transaxial or single angulated needle path and the second with a single or double angulated needle path. Puncture deviation and puncture duration were compared between the procedures and were correlated with the self-assessments. RESULTS: RiTs in both the CT guidance and CACT guidance groups did not differ with respect to radiologic experience (p = 1), angiographic experience (p = 0.415), and number of ultrasound-guided puncture procedures (p = 0.483), CT-guided puncture procedures (p = 0.934), and CACT-guided puncture procedures (p = 0.466). The puncture duration was significantly longer with CT guidance (without navigation tool) than with CACT guidance with navigation software (p < 0.001). There was no significant difference in the puncture duration between the first and second puncture using CT guidance (p = 0.719). However, in the case of CACT, the second puncture was significantly faster (p = 0.006). Puncture deviations were not different between CT-guided and CACT-guided puncture (p = 0.337) and between the first and second puncture of CT-guided and CACT-guided puncture (CT: p = 0.130; CACT: p = 0.391). The self-assessment of manual skills did not correlate with puncture deviation (p = 0.059) and puncture duration (p = 0.158). The self-assessed spatial skills correlated positively with puncture deviation (p = 0.011) but not with puncture duration (p = 0.541). CONCLUSION: The RiTs achieved a puncture deviation that was clinically adequate with respect to their level of training and did not differ between CT-guided and CACT-guided puncture. The puncture duration was shorter when using CACT. CACT guidance with navigation software support has a potentially steeper learning curve. Spatial skills might accelerate the learning of image-guided puncture. KEY POINTS: · The CT-guided and CACT-guided puncture experience of the RiTs selected as part of the program "Researchers for the Future" of the German Roentgen Society was adequate with respect to the level of training.. · Despite the lower collective experience of the RiTs with CACT-guided puncture with navigation software assistance, the learning curve regarding CACT-guided puncture may be faster compared to the CT-guided puncture technique.. · If the needle path is complex, CACT guidance with navigation software assistance might have an advantage over CT guidance.. CITATION FORMAT: · Meine TC, Hinrichs JB, Werncke T et al. Phantom study for comparison between computed tomography- and C-Arm computed tomography-guided puncture applied by residents in radiology. Fortschr Röntgenstr 2022; 194: 272 - 280.

Impact of Endoscopic Vacuum Therapy with Low Negative Pressure for Esophageal Perforations and Postoperative Anastomotic Esophageal Leaks.

INTRODUCTION: Management of esophageal anastomotic leaks (AL) and esophageal perforations (EP) remains difficult and often requires an interdisciplinary treatment modality. For primary endoscopic management, self-expanding metallic stent (SEMS) placement is often considered first-line therapy. Recently, endoscopic vacuum therapy (EVT) has emerged as an alternative or adjunct for management of these conditions. So far, data for EVT in the upper gastrointestinal-tract is restricted to single centre, non-randomized trials. No studies on optimal negative pressure application during EVT exist. The aim of our study is to describe our centre's experience with low negative pressure (LNP) EVT for these indications over the past 5-years. PATIENTS AND METHODS: Between January 2014 and December 2018, 30 patients were endoscopically treated for AL (n = 23) or EP (n = 7). All patients were primarily treated with EVT and LNP between -20 and -50 mm Hg. Additional endoscopic treatment was added when EVT failed. Procedural and peri-procedural data, as well as clinical outcomes including morbidity and mortality, were analysed. RESULTS: Clinical successful endoscopic treatment of EP and AL was achieved in 83.3% (n = 25/30), with 73.3% success using EVT alone (n = 22/30). Mean treatment duration until leak closure was 16.1 days (range 2-58 days). Additional treatment modalities for complete leak resolution was necessary in 10% (n = 3/30), including SEMS placement and fibrin glue injection. Mean hospital stay for patients with EP was shorter with 33.7 days compared to AL with 54.4 days (p = 0.08). Estimated preoperative 10-year overall survival (Charlson comorbidity score) was 39.4% in patients with AL and 59.9% in patients with EP (p = 0.26). A mean of 5.1 EVT changes (range 1-12) was needed in EP and 3.6 changes (range 1-13) in AL to achieve complete closure, switch to other treatment modality, or reach endoscopic failure (p = 0.38). CONCLUSION: LNP EVT enables effective minimally - invasive endoluminal leak closure from anastomotic esophageal leaks and EP in high-morbid patients. In this study, EVT was combined with other endoscopic treatment options such as SEMS placement or fibrin glue injection in order to achieve leak or perforation closure in the vast majority of patients (83.3%). Low aspiration pressures led to slower but still sufficient clinical results.

Assessment of esophageal motility disorders by real-time MRI.

PURPOSE: To investigate imaging findings of esophageal motility disorders on dynamic real-time. MATERIAL AND METHODS: 102 patients with GERD-like symptoms were included in this retrospective study between 2015-2018. Dynamic real-time MRI visualized the transit of a 10 mL pineapple juice bolus through the esophagus and EGJ with a temporal resolution of 40 ms. Dynamic and anatomic parameters were measured by consensus reading. Imaging findings were compared to HRM utilizing the Chicago classification of esophageal motility disorders, v3.0. RESULTS: All 102 patients completed real-time MRI in a median examination time of 15 min. On HRM, 14 patients presented with disorders with EGJ outlet obstruction (EGJOO) (13.7 %), 7 patients with major disorders of peristalsis (6.9 %), and 32 patients with minor disorders of peristalsis (31.4 %). HRM was normal in 49 patients (48.0 %). Incomplete bolus clearance was significantly more frequent in patients with esophageal motility disorders on HRM than in patients with normal HRM (p = 0.0002). In patients with motility disorders with EGJOO and major disorders of peristalsis, the esophageal diameter tended to be wider (23.6 ±â€¯8.0 vs. 21.2 ±â€¯3.5 mm, p = 0.089) and the sphincter length longer (19.7 ±â€¯7.3 vs. 16.7 ±â€¯3.0 mm, p = 0.091) compared to patients with normal HRM. 3/7 patients with achalasia type II were correctly identified by real-time MRI and one further achalasia type II patient was diagnosed with a motility disorder on MRI films. The other 3/7 patients presented no specific imaging features. CONCLUSION: Real-time MRI is an auxiliary diagnostic tool for the assessment of swallowing events. Imaging parameters may assist in the detection of esophageal motility disorders.

Discriminating malignant and benign clinical T1 renal masses on computed tomography: A pragmatic radiomics and machine learning approach.

The aim of this study was to discriminate malignant and benign clinical T1 renal masses on routinely acquired computed tomography (CT) images using radiomics and machine learning techniques.Adult patients undergoing surgical resection and histopathological analysis of clinical T1 renal masses were included. Preoperative CT studies in venous phase from multiple referring centers were included, without restriction to specific CT scanners, slice thickness, or degrees of artifacts. Renal masses were segmented and 120 standardized radiomic features extracted. Machine learning algorithms were used to predict malignancy of renal masses using radiomics features and cross-validation. Diagnostic accuracy of machine learning models and assessment by independent blinded radiologists were compared based on the gold standard of histopathologic diagnosis.A total of 94 patients met inclusion criteria (benign renal masses: n = 18; malignant: n = 76). CT studies from 18 different scanners were assessed with median slice thickness of 2.5 mm and artifacts in 15 cases (15.9%).Area under the receiver-operating-characteristics curve (AUC) of random forest (random forest [RF], AUC = 0.83) was significantly higher compared to the radiologists (AUC = 0.68, P = .047). Sensitivity was significantly higher for RF versus radiologists (0.88 vs 0.80, P = .045), whereas specificity was numerically higher for RF (0.67 vs 0.50, P = .083).Although limited by an overall small sample size and few benign renal tumors, a radiomic features and machine learning approach suggests a high diagnostic accuracy for discrimination of malignant and benign clinical T1 renal masses on venous phase CT. The presented algorithm robustly outperforms human readers in a real-life scenario with nonstandardized imaging studies from various referring centers.

Real-time MRI for dynamic assessment of gastroesophageal reflux disease: Comparison to pH-metry and impedance.

PURPOSE: To evaluate the diagnostic potential of real-time MRI for dynamic assessment of gastroesophageal reflux in patients with GERD (gastroesophageal reflux disease)-like symptoms compared to pH-metry and impedance. METHODS: Patients who underwent real-time MRI and pH-metry between 2015-2018 were included in this retrospective study. Real-time MRI at 3 T was achieved by undersampled radial FLASH acquisitions with iterative image reconstruction by NLINV. Real-time MRI visualized transit of pineapple juice through the gastroesophageal junction and during Valsalva maneuver. MRI results were compared to 24 h pH-metry to assess acidic reflux (following Lyon Consensus guidelines) and to impedance to assess non-acidic reflux. A standard 2 × 2 table was chosen to calculate diagnostic performance. RESULTS: 91/93 eligible patients fulfilled inclusion criteria (male n = 49; female n = 42; median age 55 y). All MRI studies were successfully completed without adverse events at a mean examination time of 15 min. On real-time MRI, reflux was evident in 60 patients (66 %). pH-metry revealed reflux in 41 patients (45 %), and impedance in 54 patients (59 %). Compared to pH-metry and impedance, real-time MRI sensitivity was 0.78 (95 % CI: 0.66-0.87), specificity 0.67 (95 % CI: 0.45-0.84) and PPV 0.87 (95 % CI: 0.75-0.94). CONCLUSION: Real-time MRI is an imaging method for assessment of gastroesophageal reflux in patients with GERD-like symptoms. Considering its high positive predictive value, real-time MRI can accurately identify patients in which further invasive testing with pH-metry and impedance might be considered.

Future liver remnant growth after various portal vein embolization regimens: a quantitative comparison.

Purpose: To compare the efficacy of right portal vein embolization using ethylene vinyl alcohol (EVOH-PVE) compared to other embolic agents and surgical right portal vein ligation (PVL).Material and methods: Patients with right sided liver malignancies scheduled for extensive surgery and receiving induction of liver hypertrophy via right portal vein embolization/ligature between 2010-2016 were retrospectively evaluated. Treatments included were ethylene vinyl alcohol copolymer (Onyx®, EVOH-PVE), ethiodized oil (Lipiodol®, Lipiodol/PVA-PVE), polyvinyl alcohol (PVA-PVE) or surgical ligature (PVL). Liver segments S2/3 were used to assess hypertrophy. Primary outcome was future liver remnant growth in ml/day.Results: Forty-one patients were included (EVOH-PVE n = 11; Lipiodol/PVA-PVE n = 10; PVA-PVE n = 8; PVL n = 12), the majority presenting with cholangiocarcinoma and colorectal metastases (n = 11; n = 27). Pre-interventional liver volumes were comparable (p = .095). Liver hypertrophy was successfully induced in all but one patient receiving Lipiodol/PVA-PVE. Liver segment S2/3 growth was largest for EVOH-PVE (5.38 ml/d) followed by PVA-PVE (2.5 ml/d), with significantly higher growth rates than PVL (1.24 ml/d; p < .001; p = .007). No significant difference was evident for Lipiodol/PVA-PVE (1.43 ml/d, p = .809).Conclusions: Portal vein embolization using EVOH demonstrates fastest S2/3 growth rates compared to other embolic agents and PVL, potentially due to its permanent portal vein embolization and induction of hepatic inflammation.

Hiatal hernias in patients with GERD-like symptoms: evaluation of dynamic real-time MRI vs endoscopy.

PURPOSE: To assess the diagnostic potential of real-time MRI for assessment of hiatal hernias in patients with GERD-like symptoms compared to endoscopy. MATERIAL AND METHODS: One hundred eight patients with GERD-like symptoms were included in this observational cohort study between 2015 and 2017. Real-time MRI was performed at 3.0 Tesla with temporal resolution of 40 ms, dynamically visualizing the esophageal transport of a pineapple juice bolus, its passage through the gastroesophageal junction, and functional responses during Valsalva maneuver. Hernia detection on MRI and endoscopy was calculated using contingency tables with diagnosis of hernia on either modality as reference. RESULTS: Of 108 patients, 107 underwent successful MRI without adverse events; 1 examination was aborted to inability to swallow pineapple juice in supine position. No perforation or acute bleeding occurred during endoscopy. Median examination time was 15 min. Eighty-five patients (79.4%) were diagnosed with hiatal hernia on either real-time MRI or endoscopy. Forty-six hernias were visible on both modalities. Seventeen hernias were evident exclusively on MRI, and 22 exclusively on endoscopy. Sixteen of the 63 MRI-detected hernias (25.4%) were detectable only during Valsalva maneuver, which were smaller compared to hernias at rest (median - 13.5 vs - 33.0 mm, p < 0.001). Diagnostic accuracy for hernia detection was comparable for MRI and endoscopy (sensitivity 74% vs 80%, p = 0.4223; specificity 100% vs 100%, p > 0.99). CONCLUSION: Real-time MRI is a fast and safe modality for assessment of the gastroesophageal junction, without radiation exposure or administration of gadolinium-based contrast media. Although MRI and endoscopy yield comparable diagnostic accuracy, dynamic MRI sequences are able to visualize hiatal hernias that were occult on static MRI sequences or endoscopy in a relevant number of cases. KEY POINTS: • Real-time MRI is a safe and fast imaging modality for examination of the gastroesophageal junction, combining anatomical and functional information for enhanced detection of hiatal hernias. • Real-time MRI and endoscopy yield comparably high diagnostic accuracy: real-time MRI visualizes hiatal hernias that were occult on endoscopy in a relevant number of patients; however, several hiatal hernias detected on endoscopy were occult on real-time MRI. • There is clinical potential of real-time MR imaging in patients with GERD-like symptoms and equivocal findings on endoscopy or pH-metry, for anatomical visualization in patients planned for surgical intervention, or those with suspected fundoplication failures.