Artificial Intelligence for Clinical Interpretation of Bedside Chest Radiographs.

Background Supine chest radiography for bedridden patients in intensive care units (ICUs) is one of the most frequently ordered imaging studies worldwide. Purpose To evaluate the diagnostic performance of a neural network-based model that is trained on structured semiquantitative radiologic reports of bedside chest radiographs. Materials and Methods For this retrospective single-center study, children and adults in the ICU of a university hospital who had been imaged using bedside chest radiography from January 2009 to December 2020 were reported by using a structured and itemized template. Ninety-eight radiologists rated the radiographs semiquantitatively for the severity of disease patterns. These data were used to train a neural network to identify cardiomegaly, pulmonary congestion, pleural effusion, pulmonary opacities, and atelectasis. A held-out internal test set (100 radiographs from 100 patients) that was assessed independently by an expert panel of six radiologists provided the ground truth. Individual assessments by each of these six radiologists, by two nonradiologist physicians in the ICU, and by the neural network were compared with the ground truth. Separately, the nonradiologist physicians assessed the images without and with preliminary readings provided by the neural network. The weighted Cohen κ coefficient was used to measure agreement between the readers and the ground truth. Results A total of 193 566 radiographs in 45 016 patients (mean age, 66 years ± 16 [SD]; 61% men) were included and divided into training (n = 122 294; 64%), validation (n = 31 243; 16%), and test (n = 40 029; 20%) sets. The neural network exhibited higher agreement with a majority vote of the expert panel (κ = 0.86) than each individual radiologist compared with the majority vote of the expert panel (κ = 0.81 to ≤0.84). When the neural network provided preliminary readings, the reports of the nonradiologist physicians improved considerably (aided vs unaided, κ = 0.87 vs 0.79, respectively; P < .001). Conclusion A neural network trained with structured semiquantitative bedside chest radiography reports allowed nonradiologist physicians improved interpretations compared with the consensus reading of expert radiologists. © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Wielpütz in this issue.

Safety and efficacy of right portal vein embolization in patients with prior left lateral liver resection.

BACKGROUND: In patients with bilobar metastatic liver disease, surgical clearance of both liver lobes may be achieved through multiple-stage liver resections. For patients with extensive disease, a major two-staged hepatectomy consisting of resection of liver segments II and III before right-sided portal vein embolization (PVE) and resection of segments V-VIII may be performed, leaving only segments IV ± I as the liver remnant. PURPOSE: To describe the outcome following right-sided PVE after prior complete resection of liver segments II and III. MATERIAL AND METHODS: In this retrospective study, 15 patients (mean age = 60.4 ± 9.3 years) with liver metastases from colorectal cancer (n = 14) and uveal melanoma (n = 1) who were scheduled to undergo a major two-stage hepatectomy, were included. Total liver volume (TLV) and volume of the future liver remnant (FLR) were measured on pre- and postinterventional computed tomography (CT) scans, and standardized FLR volumes (ratio FLR/TLV) were calculated. Patient data were retrospectively analyzed regarding peri- and postinterventional complications, with special emphasis on liver function tests. RESULTS: The mean standardized post-PVE FLR volume was 26.9% ± 6.4% and no patient developed hepatic insufficiency after the PVE. Based on FLR hypertrophy and liver function tests, all but one patient were considered eligible for the subsequent right-sided hepatectomy. However, due to local tumor progression, only 9/15 patients eventually proceeded to the second stage of surgery.  . CONCLUSION: Right-sided PVE was safe and efficacious in this cohort of patients who had previously undergone a complete resection of liver segments II and III as part of a major staged hepatectomy pathway leaving only segments IV(±I) as the FLR. .

Heparan sulfate proteoglycan expression in the regenerating zebrafish fin.

BACKGROUND: Heparan sulfate proteoglycan (HSPG) expression is found in many animal tissues and regulates growth factor signaling such as of Fibroblast growth factors (Fgf), Wingless/Int (Wnt) and Hedgehog (HH). Glypicans, which are GPI (glycosylphosphatidylinositol)-anchored proteins, and transmembrane-anchored syndecans represent two major HSPG protein families whose involvement in development and disease has been demonstrated. Their participation in regenerative processes both of the central nervous system and of regenerating limbs is well documented. However, whether HSPG are expressed in regenerating zebrafish fins, is currently unknown. RESULTS: Here, we carried out a systematic screen of glypican and syndecan mRNA expression in regenerating zebrafish fins during the outgrowth phase. We find that 8 of the 10 zebrafish glypicans and the three known zebrafish syndecans show specific expression at 3 days post amputation. Expression is found in different domains of the regenerate, including the distal and lateral basal layers of the wound epidermis, the distal most blastema and more proximal blastema regions. CONCLUSIONS: HSPG expression is prevalent in regenerating zebrafish fins. Further research is needed to delineate the function of glypican and syndecan action during zebrafish fin regeneration.

Percutaneous transhepatic biliary drainage (PTBD) in patients with dilated vs. nondilated bile ducts: technical considerations and complications.

OBJECTIVES: The aim of this study was to compare success, technical complexity, and complication rates of percutaneous transhepatic biliary drainage (PTBD) in patients with dilated vs. nondilated bile ducts. METHODS: In a retrospective analysis, we evaluated all consecutive PTBD performed in our department over a period of 5 years. Technical success, technical data (side, fluoroscopy time, radiation dose, amount of contrast media, use of disposable equipment), procedure-related complications and peri-interventional mortality were compared for patients with dilated vs. non-dilated bile ducts. Independent t test and χ2 test were used to evaluate the statistical significance. RESULTS: A total of 253 procedures were performed on 187 patients, of whom 101/253 had dilated bile ducts and 152/253 not. In total, 243/253 procedures were successful. PTBD was significantly more often successful in patients with dilated vs. nondilated bile ducts (150/153 vs. 93/101; p 0.02). Overall complication rate (13%) did not differ significantly between patients with dilated vs. nondilated bile ducts. Procedures in patients with normal, nondilated bile ducts were associated with a significantly higher rate of post-interventional bleeding (5/101 vs. 0/152). Mean fluoroscopy time (42:36 ± 35:39 h vs. 30:28 ± 25:10 h; p 0.002) and amount of contrast media (66 ± 40 ml vs. 52 ± 24 ml; p 0.07) or use of disposables were significantly higher in patients with nondilated ducts. A significantly lower fluoroscopy time and amount of contrast medium were used in left hepatic PTBD. CONCLUSION: Despite the higher technical complexity, PTBD with nondilated bile ducts was associated with similar overall complication rates but higher bleeding complications compared with PTBD with dilated bile ducts. KEY POINTS: • PTBD was associated with similar overall complication rates in patients with dilated vs. nondilated bile ducts. • Although overall complication rates were low, PTBD in patients with nondilated bile ducts was associated with a higher incidence of post-interventional bleeding. • PTBD in patients with nondilated bile ducts is technically more complex.

Hemosuccus Pancreaticus and Obstructive Jaundice: Two Rare Complications of Chronic Pancreatitis Treated by Arterial Embolization.

The formation of a peripancreatic pseudoaneurysm is a rare and serious complication of chronic pancreatitis. In this report, we present the case of a 56-year-old male with a history of alcohol-related chronic pancreatitis resulting in both hemosuccus pancreaticus and obstructive jaundice due to a pseudoaneurysm of the gastroduodenal artery that was treated successfully by angiographic coiling.

Volumetric measurements of target lesions: does it improve inter-reader variability for oncological response assessment according to RECIST 1.1 guidelines compared to standard unidimensional measurements?

PURPOSE: Target lesion selection is known to be a major factor for inter-reader discordance in RECIST 1.1. The purpose of this study was to assess whether volumetric measurements of target lesions result in different response categorization, as opposed to standard unidimensional measurements, and to evaluate the impact on inter-reader agreement for response categorization when different readers select different sets of target lesions. MATERIAL AND METHODS: Fifty patients with measurable disease from solid tumours, in which 3 readers had blindly and independently selected different sets of target lesions and subsequently reached clinically significant discordant response categorizations (progressive disease [PD] vs. non-progressive disease [non-PD]) based on RECIST 1.1 analyses were included in this study. Additional volumetric measurements of all target lesions were performed by the same readers in a second read. Intra-reader agreement between standard unidimensional measurements (uRECIST) and volumetric measurements (vRECIST) was assessed using Cohen's k statistics. Fleiss k statistics was used to analyse the inter-reader agreement for uRECIST and vRECIST results. RESULTS: The 3 readers assigned the same response classifications based on uRECIST and vRECIST in 33/50 (66%), 42/50 patients (84%), and 44/50 patients (88%), respectively. Inter-reader agreement improved from 0% when using uRECIST to 36% when using vRECIST. CONCLUSIONS: Volumetric measurement of target lesions may improve inter-reader variability for response assessment as opposed to standard unidimensional measurements. However, in about two-thirds of patients, readers disagreed regardless of the measurement method, indicating that a limited set of target lesions may not be sufficiently representative of the whole-body tumour burden.

Validity of RECIST Version 1.1 for Response Assessment in Metastatic Cancer: A Prospective, Multireader Study.

Purpose To determine the relationship between target lesion selection with use of Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and classification of therapeutic response in patients with metastatic cancer undergoing systemic cytotoxic and/or targeted therapies. Materials and Methods This prospective multireader study was conducted between July 2015 and July 2017. Three hundred sixteen consecutive participants with metastatic cancer underwent 932 CT examinations to monitor systemic treatment. CT studies were independently read by three radiologists. Readers identified a maximum of five lesions total (and a maximum of two lesions per organ). Dedicated oncology tumor response software was used. The Fleiss κ statistic was used to analyze interreader agreement in the assignment of individual response classes (complete response, partial response, progressive disease, or stable disease) and in the differentiation between progressive and nonprogressive disease. Results Readers selected the same set of target lesions in 128 of the 316 participants (41%) and selected a different set in 188 (59%). When target lesion selection was concordant, agreement was high (assignment of treatment response category: κ = 0.97; 95% confidence interval [CI]: 0.91, 1.0; differentiation between progressive and nonprogressive disease: κ = 0.98; 95% CI: 0.90, 1.0). When target lesion selection was discordant, agreement was significantly reduced (assignment of treatment response category: κ = 0.58; 95% CI: 0.54, 0.62; differentiation between progressive and nonprogressive disease: κ = 0.6; 95% CI: 0.59, 0.70). With concordant target lesion selection, readers agreed regarding diagnosis of progression in 97.7% of participants (95% CI: 95.4%, 100.0%); with discordant target lesion selection, readers agreed in only 55.3% (95% CI: 47.9%, 62.6%) (P < .01). Conclusion In patients with metastatic cancer undergoing systemic treatment, different cancer sites may appear similarly suitable and thus likely to be selected as target lesions but may yield inconsistent or even conflicting results with Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. This indicates that the current, limited set of target lesions in RECIST 1.1 may not reflect overall tumor load or response to therapy. © RSNA, 2018 See also the editorial by Sosna in this issue.

Midterm Safety and Efficacy of Irreversible Electroporation of Malignant Liver Tumors Located Close to Major Portal or Hepatic Veins.

Purpose To investigate the efficacy and safety of irreversible electroporation (IRE) in the treatment of hepatic tumors not suitable for thermal ablation (radiofrequency ablation [RFA] or microwave ablation). Materials and Methods This was an institutional review board-approved prospective study in 29 patients (15 men, 14 women; mean age, 63 years ± 12 [standard deviation]) with 43 primary (n = 8) or secondary (n = 35) malignant liver tumors who underwent computed tomography (CT)-guided IRE. All target tumors were located immediately adjacent to major hepatic veins, portal veins, or both; thus, they were not considered suitable for RFA or microwave ablation. Patients underwent postinterventional CT and magnetic resonance (MR) imaging. Systematic follow-up MR imaging was performed for 24 months on average to assess complete ablation, intrahepatic tumor recurrence, and complications. The 95% confidence intervals (CIs) were determined for the rate of bile duct strictures, incomplete ablation, and tumor recurrence. Results Complete ablation was achieved in 40 (93%; 95% CI: 85, 100) of 43 target tumors, with a safety margin of 5-10 mm, and was confirmed at immediate postinterventional CT and MR imaging. In 13 (33%; 95% CI: 18, 47) of 40 completely ablated tumors, intrahepatic tumor recurrence was observed at 2-18 months. However, only two (15%; 95% CI: 0, 35) of these 13 tumors were observed within the ablation zone. In the remaining 11 (85%; 95% CI: 65, 100), tumor growth was observed alongside the needle tract. None of the two true local recurrences occurred at the site of the vessel. All adjacent vessels remained perfused at follow-up. Five (24%; 95% CI: 5, 39) of 21 patients with target tumors adjacent to portal veins developed mild to moderate cholestasis 2-6 weeks after IRE. Conclusion IRE is useful to avoid incomplete ablation secondary to heat-sink effects and damage to major blood vessels; however, needle tract seeding is observed in 26% of treated tumors, and IRE induces sufficient local heating to bile ducts in 24% of ablations. © RSNA, 2017.

Jugular bulb abnormalities in patients with Meniere's disease using high-resolution computed tomography.

Temporal bone abnormalities such as hypoplasia of the vestibular aqueduct or hypopneumatization of the mastoid have been described in Meniere's disease (MD). Jugular bulb abnormalities (JBA) are one of the most common temporal bone abnormalities. The aim of this study was to evaluate the frequency of JBA in MD. Radiological data obtained by temporal bone high-resolution computed tomography of 200 ears of 167 MD patients (MD group) and 218 ears of 109 patients with normal inner ear function (control group) were analyzed retrospectively. The frequencies of high jugular bulb (HJB), jugular bulb diverticulum (JBD), inner ear adjacent jugular bulb (IAJB) and jugular bulb related inner ear dehiscence (JBID) were evaluated and compared between MD group and control group. IAJB was differentiated into vestibular aqueduct adjacent jugular bulb (VAAJB), cochlear aqueduct adjacent jugular bulb and posterior semicircular canal adjacent jugular bulb. JBID was further analyzed by differentiating into jugular bulb related vestibular aqueduct dehiscence (JBVAD), jugular bulb related cochlear aqueduct dehiscence and jugular bulb related posterior semicircular canal dehiscence. The frequencies of HJB, JBD and IAJB were higher in MD group compared to control group (21, 13.3 %, p = 0.036; 8.5, 3.7 %, p = 0.037; 13.5, 4.6 %, p = 0.001). No differences between both groups were seen in JBID (4.0, 2.3 %, p = 0.315). Most IAJB and JBID were seen in VAAJB and JBVAD. There is a higher frequency of JBA in patients with MD than in patients without inner ear symptoms. Temporal bones of MD patients might be constituted anatomically different, carrying predisposing factors for the development of clinically apparent MD.

Radiological findings of the cochlear aqueduct in patients with Meniere's disease using high-resolution CT and high-resolution MRI.

The objective of the present study was to evaluate the cochlear aqueduct (CA) in Meniere's disease (MD) and to disclose radiological differences of CA between MD and non-MD patients by means of high-resolution computed tomography (HRCT) and high-resolution magnetic resonance imaging (HRMRI). Radiological data of 86 ears of MD patients which were separated into 52 ears of diseased side group (MD-D group) and 34 ears of contralateral non-affected side group of unilateral MD (MD-ND group), 27 ears of patients with sensorineural hearing loss (SNHL group) and 56 ears of patients with somatoform dizziness and normal hearing (control group) were analyzed retrospectively. The bony type of CA, the bony length of CA, and the bony width of CA medial orifice was measured in HRCT. The visibility of CA in HRMRI was scored. Fluid length in CA and fluid width in medial orifice were measured in HRMRI. Data were compared between MD-D, MD-ND, SNHL, and control group. There were no significant differences in the bony type of CA, bony length of CA, bony width of CA medial orifice, and fluid width of CA medial orifice between MD-D, MD-ND, SNHL and control group (p > 0.05). However, CA fluid length of MD-D (5.13 ± 1.88 mm) and of MD-ND group (5.44 ± 1.81 mm) was significantly shorter than fluid length of SNHL (6.90 ± 1.55 mm) (p < 0.001, p = 0.001) and of control group (7.43 ± 1.24 mm) (p < 0.001, p < 0.001). The ratio between CA fluid length and CA bony length was the smallest in MD-D group (0.403; p = 0.009). CA bony dimensions of affected ears of MD are normal, but CA fluid length is decreased.

Evaluation of Pulmonary Nodules by Radiologists vs. Radiomics in Stand-Alone and Complementary CT and MRI.

Increased attention has been given to MRI in radiation-free screening for malignant nodules in recent years. Our objective was to compare the performance of human readers and radiomic feature analysis based on stand-alone and complementary CT and MRI imaging in classifying pulmonary nodules. This single-center study comprises patients with CT findings of pulmonary nodules who underwent additional lung MRI and whose nodules were classified as benign/malignant by resection. For radiomic features analysis, 2D segmentation was performed for each lung nodule on axial CT, T2-weighted (T2w), and diffusion (DWI) images. The 105 extracted features were reduced by iterative backward selection. The performance of radiomics and human readers was compared by calculating accuracy with Clopper-Pearson confidence intervals. Fifty patients (mean age 63 +/- 10 years) with 66 pulmonary nodules (40 malignant) were evaluated. ACC values for radiomic features analysis vs. radiologists based on CT alone (0.68; 95%CI: 0.56, 0.79 vs. 0.59; 95%CI: 0.46, 0.71), T2w alone (0.65; 95%CI: 0.52, 0.77 vs. 0.68; 95%CI: 0.54, 0.78), DWI alone (0.61; 95%CI:0.48, 0.72 vs. 0.73; 95%CI: 0.60, 0.83), combined T2w/DWI (0.73; 95%CI: 0.60, 0.83 vs. 0.70; 95%CI: 0.57, 0.80), and combined CT/T2w/DWI (0.83; 95%CI: 0.72, 0.91 vs. 0.64; 95%CI: 0.51, 0.75) were calculated. This study is the first to show that by combining quantitative image information from CT, T2w, and DWI datasets, pulmonary nodule assessment through radiomics analysis is superior to using one modality alone, even exceeding human readers' performance.

Encrypted federated learning for secure decentralized collaboration in cancer image analysis.

Artificial intelligence (AI) has a multitude of applications in cancer research and oncology. However, the training of AI systems is impeded by the limited availability of large datasets due to data protection requirements and other regulatory obstacles. Federated and swarm learning represent possible solutions to this problem by collaboratively training AI models while avoiding data transfer. However, in these decentralized methods, weight updates are still transferred to the aggregation server for merging the models. This leaves the possibility for a breach of data privacy, for example by model inversion or membership inference attacks by untrusted servers. Somewhat-homomorphically-encrypted federated learning (SHEFL) is a solution to this problem because only encrypted weights are transferred, and model updates are performed in the encrypted space. Here, we demonstrate the first successful implementation of SHEFL in a range of clinically relevant tasks in cancer image analysis on multicentric datasets in radiology and histopathology. We show that SHEFL enables the training of AI models which outperform locally trained models and perform on par with models which are centrally trained. In the future, SHEFL can enable multiple institutions to co-train AI models without forsaking data governance and without ever transmitting any decryptable data to untrusted servers.

Fibroblast growth factor pathway component expression in the regenerating zebrafish fin.

Adult zebrafish regenerate their appendages (fins) after amputation including the regeneration of bone structures (fin rays). Fibroblast growth factor (Fgf) signaling, which is involved in morphogenetic processes during development, has been shown to be essential for the process of fin regeneration. Moreover, mutations in Fgf pathway component genes lead to abnormal skeletal growth in teleosts and mammals, including humans, illustrating the importance of Fgf signaling in the growth control of tissues. Here, we revisited Fgf signaling pathway component expression by RNA in situ hybridization to test for the expression of about half of the ligands and all receptors of the pathway in the regenerating zebrafish fin. Expression patterns of fgf7, fgf10b, fgf12b, fgf17b and fgfr1b have not been reported in the literature before. We summarize and discuss known and novel localization of expression and find that all five Fgf receptors (fgfr1a, fgfr1b, fgfr2, fgfr3 and fgfr4) and most of the tested ligands are expressed in specific regions of the regenerate. Our work provides a basis to study domain specific functions of Fgf signaling in the regenerating teleost appendage.

Calcification of the visceral aorta and celiac trunk is associated with renal and allograft outcomes after deceased donor liver transplantation.

PURPOSE: Atherosclerosis affects clinical outcomes in the setting of major surgery. Here we aimed to investigate the prognostic role of visceral aortic (VAC), extended visceral aortic (VAC+), and celiac artery calcification (CAC) in the assessment of short- and long-term outcomes following deceased donor orthotopic liver transplantation (OLT) in a western European cohort. METHODS: We retrospectively analyzed the data of 281 consecutive recipients who underwent OLT at a German university medical center (05/2010-03/2020). The parameters VAC, VAC+, or CAC were evaluated by preoperative computed tomography-based calcium quantification according to the Agatston score. RESULTS: Significant VAC or CAC were associated with impaired postoperative renal function (p = 0.0016; p = 0.0211). Patients with VAC suffered more frequently from early allograft dysfunction (EAD) (38 vs 26%, p = 0.031), while CAC was associated with higher estimated procedural costs (p = 0.049). In the multivariate logistic regression analysis, VAC was identified as an independent predictor of EAD (2.387 OR, 1.290-4.418 CI, p = 0.006). Concerning long-term graft and patient survival, no significant difference was found, even though patients with calcification showed a tendency towards lower 5-year survival compared to those without (VAC: 65 vs 73%, p = 0.217; CAC: 52 vs 72%, p = 0.105). VAC+ failed to provide an additional prognostic value compared to VAC. CONCLUSION: This is the first clinical report to show the prognostic role of VAC/CAC in the setting of deceased donor OLT with a particular value in the perioperative phase. Further studies are warranted to validate these findings. CT computed tomography, OLT orthotopic liver transplantation.

Long loop technique with bifemoral access as salvage technique for repositioning of dislodged port catheters.

BACKGROUND: Repositioning of dislocated port systems' catheters is usually performed with a pigtail catheter and/or a goose snare. In case of an inaccessible port catheter tip due to thrombosis, this classic approach may be not successful. For these cases, we describe a long loop bailout technique with bifemoral access. TECHNIQUE: Via a right transfemoral access, a first attempt to reposition the dislodged port catheter using pigtail catheter and goose snare was performed. After an unsuccessful attempt and delineation of thrombosis of the catheter tip, the contralateral femoral vein was subsequently punctured and a sheath was placed. Through both vascular sheaths, pigtail catheter and goose wire were advanced distally to the catheter. The guidewire in the pigtail catheter was snared, thus creating a "Long loop" configuration. Pulling down both catheters simultaneously with improved stability allowed to detach the catheter tip from the vessel wall and replacement into the superior vena cava was possible. Refinement of catheter tip position was done using the goose snare. This technique was applied on 5 patients with dislodged port catheters in the jugular vein (2/5), the innominate vein (1/5), the subclavian vein (1/5) and the azygos vein (1/5) with a technical success of 100%. No complications were observed. CONCLUSION: The Long loop technique can be used as salvage approach to reposition a dislodged catheter in case of failure with pigtail catheter and goose snare.

Recurrent Colorectal Liver Metastases in the Liver Remnant After Major Liver Surgery-IRE as a Salvage Local Treatment When Resection and Thermal Ablation are Unsuitable.

PURPOSE: To examine the safety and short-term oncologic outcomes of computer-tomography-guided (CT-guided) irreversible electroporation (IRE) of recurrent, irresectable colorectal liver metastases (CRLM) after major hepatectomy deemed unsuitable for thermal ablation. PATIENTS AND METHODS: Twenty-three patients undergoing CT-guided IRE of recurrent CRLM after major hepatectomy were included in this study. All tumors were located adjacent to sole remaining intrahepatic blood vessels and bile ducts, precluding thermal ablation. Patients underwent systematic clinical and imaging follow-up, including magnetic resonance imaging of the liver at 1-month and 3-month intervals thereafter. Time to local and intrahepatic tumor progression within 12 and 36 months and associated risk factors were assessed using Kaplan Meier and Cox regression analysis, respectively. RESULTS: Complete ablation with a safety margin of at least 0.5 cm was achieved in 22/23 (95.6%) patients. No vessel injury or thrombosis occurred. Five patients developed moderate biliary stenosis after a median of 4 weeks, without requiring treatment. Local tumor-progression-free rates within 12/36 months were 64%/57.4%, respectively. Intrahepatic-progression-free rate within 12/36 months was 36.4%/19.5%, respectively. Five (23%) patients were tumor-free at the end of follow-up. Multivariate Cox regression analysis did not show any association between local tumor-progression-free rates and patient age, target tumor size, primary tumor side or synchronicity of liver metastases. CONCLUSION: In this highly selected patient population with local recurrences of CRLM after major surgery, IRE was shown to be a safe salvage treatment option when thermal ablation is unsuitable.

Detectability of Target Lesion During CT-Guided Tumor Ablations: Impact on Ablation Outcome.

PURPOSE: Small hepatic malignancies scheduled for CT-guided percutaneous ablation may have been identified in the hepatobiliary phase of liver MRI or in a specific phase of multi-phase CT but may be occult on unenhanced CT used to guide the ablation. We investigated whether the detectability of the target lesion would impact the efficacy of CT-guided hepatic tumor ablations. MATERIALS AND METHODS: We included 69 patients with 99 malignant liver lesions (25 primary, 44 metastases) who underwent IRE (n = 35), RFA (n = 41), or MWA (n = 23) between 01/2015 and 06/2018. All procedures were performed under CT guidance. Lesions not detectable on CT (NDL) were targeted through identification of anatomical landmarks on preinterventional contrast-enhanced CT or MRI. Rates of incomplete ablation, size of ablation zone, local tumor recurrence, intrahepatic progression-free survival (ihPFS), and adverse event rates were compared for detectable lesions (DL) vs. NDL. RESULTS: 40 lesions were NDL, and 59 lesions were DL on unenhanced CT. The mean follow-up was 16.2 months (14.8 for DL and 18.2 for NDL). The mean diameter of NDL and DL was similar (12.9 mm vs. 14.9 mm). The mean ablation zone size was similar (37.1 mm vs. 38.8 mm). Incomplete ablation did not differ between NDL vs. DL (5.0 % [2/40; 0.6-16.9 %] vs. 3.4 % [2/59; 0.4-11.7 %]), nor did local tumor recurrence (15.4 % [6/39; 5.7 %-30.5 %] vs. 16.9 % [10/59; 8.4-29.0 %]), or median ihPFS (15.5 months vs. 14.3 months). CONCLUSION: Target lesion detectability on interventional CT does not have a significant impact on outcome after percutaneous liver ablation when anatomical landmarks are used to guide needle placement. KEY POINTS: · Liver tumors can be successfully ablated even if they are not detectable on the navigational CT scan.. · Anatomical landmarks should be used and compared to preinterventional imaging.. CITATION FORMAT: · Barzakova E, Senthilvel N, Bruners P et al. Detectability of Target Lesion During CT-Guided Tumor Ablations: Impact on Ablation Outcome . Fortschr Röntgenstr 2022; 194: 515 - 520.

Impaction of a Percutaneous Heart Pump in Iliac Artery and Its Removal Using Snare.

In the process of forceful pulling out of an entangled placement guidewire, the percutaneous heart pump catheter folded in on itself and, on withdrawal farther down in the aorta, became impacted in the right common iliac artery. We describe the removal of this impacted catheter with the help of snare. (Level of Difficulty: Advanced.).

CT-based whole-body tumor volumetry versus RECIST 1.1: Feasibility and implications for inter-reader variability.

PURPOSE: To investigate whether volumetric measurements of the whole-body tumor volume (WBTV) are feasible and whether they improve inter-reader variability in patients in whom conventional RECIST 1.1 assessment yielded discordant results. METHODS: 50 patients (29 male, 21 female, mean age 60.9 ±â€¯12.3 years) with metastases of solid tumors in whom three readers had selected different sets of target lesions and subsequently reached different results for response assessment (progressive vs. non-progressive disease) when using RECIST 1.1 were included. In a second read, all readers performed volumetric measurements of the WBTV on neck/chest/abdomen/pelvis CTs and measured the time needed for these measurements. Cohen's kappa and Fleiss kappa statistics were used to compare the intra- and inter-reader agreement for response assessment. RESULTS: In 8/50 patients (16 %), the WBTV was too extensive for volumetric measurements and these patients were therefore excluded. In the remaining 42 patients, WBTV measurements required a mean time of 18 min and 9 s. Readers assigned the same response categorizations based on unidimensional RECIST measurements and WBTV measurements in 15/42 patients (33 %), 24/42 patients (57 %) and 30/42 patients (71 %) for reader 1,2 and 3 respectively. When performing response assessment based on WBTV measurements, the three readers agreed in 40/42 patients (95 %) regarding the distinction progressive vs. non-progressive disease, resulting in a near-perfect agreement on a patient-based level (Fleiss' κ = 0.921, 0.95-CI:0.746-1.095). CONCLUSIONS: WBTV measurements yielded an almost perfect inter-reader agreement in a cohort of patients, in which three readers reached discordant response assessment results when following conventional RECIST 1.1 guidelines. This supports the hypothesis, that a limited subset of metastases may not be sufficient to accurately assess response-to-treatment.

Factors That Drive Heterogeneity of Response-to-Treatment of Different Metastatic Deposits Within the Same Patients as Measured by RECIST 1.1 Analyses.

RATIONALE AND OBJECTIVE: This study uses the rate of between-reader variability under Response Evaluation Criteria for Solid Tumors (RECIST) 1.1 as a metric to estimate the prevalence of biologic heterogeneity of individual metastases, and to determine whether this prevalence is modulated by the type of primary tumor, or type of treatment administered. MATERIALS AND METHODS: Three radiologists independently used dedicated oncologic response-assessment software (MintLesion) to prospectively determine RECIST1.1 treatment response in contrast-enhanced computed tomography studies of 355 patients with metastatic disease of different primaries between 07/2015 and 12/2017. In 200 patients, readers had chosen different sets of target lesions; these cases were used for further analysis. Clinically significant heterogeneity of response was considered to be present when RECIST1.1 results differed regarding the distinction of progressive versus non-progressive disease. Rates of response heterogeneity were compared for different types of primary cancers, and different types of systemic treatment. RESULTS: Heterogeneous treatment response was observed in 67 of 200 (34%) patients. Breast cancer was the only primary tumor associated with statistically significantly increased odds for heterogeneity of treatment response (Odds Ratio: 3.972, 0.95 Confidence Interval: 1.275-12.376, p = 0.017). No association was found between type of systemic treatment and rate of biologic heterogeneity. CONCLUSION: Clinically significant heterogeneity of response-to-treatment is a frequent phenomenon, observed in about one-third of patients undergoing contemporary systemic therapies. Patients with breast cancer are more likely to exhibit such heterogeneity. Type of systemic treatment did not modulate the likelihood of exhibiting metastases with diverging treatment response.