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Background: The aim of this study was to compare microwave ablation (MWA) with and without prior placement of an intra-arterial catheter for the purpose of application of contrast medium (CM)., Methods: 148 patients (45 female, 65.1 ± 14.9 years) with liver tumors who underwent CT-guided MWA were included. Of these, 25 patients had an IA catheter placed in the hepatic artery., Results: 37 patients underwent planning imaging for MWA without CM. A total of 86 patients received a standard dose of 80 mL intravenous (IV) CM for the planning scans. The patients with an IA catheter ( n = 25) received an IA application of 10 mL CM. A total of 29 patients received contrast-enhanced scans in the PV phase for control of needle positioning after IV application of a standard dose of 80 mL CM. In patients with an IA catheter, control of the needle position was performed by single-slice scans. IA CM application during the ablation enabled monitoring of the ablation zone. Over the entire intervention, patients with IA catheters received less CM as compared to patients without an IA catheter (39.1 ± 10.4 mL vs. 141 ± 39.69 mL; p < 0.001)., Conclusions: IA catheter placement was associated with a significant decrease of the amount of CM during MWA and enabled monitoring of the ablation zone.

Objective: The Node-RADS classification was recently published as a classification system to better characterize lymph nodes in oncological imaging. The present analysis investigated the diagnostic benefit of the Node-RADS classification of staging computed tomography (CT) images to categorize and stage lymph nodes in patients with colon cancer., Materials and Methods: All patients were surgically resected and the lymph nodes were histopathological analyzed. All investigated lymph nodes were scored in accordance to the Node-RADS classification by two experienced radiologists. Interreader variability was assessed with Cohen's kappa analysis, discrimination analysis was performed with Mann-Whitney-U test and diagnostic accuracy was assessed with receiver-operating characteristics (ROC) curve analysis., Results: Overall, 108 patients (n = 49 females, 45.3%) with a mean age of 70.08 ± 14.34 years were included. In discrimination analysis, the total Node-RADS score showed statistically significant differences between N- and N + stage (for reader 1: mean 1.89 ± 1.09 score for N- versus 2.93 ± 1.62 score for N+, for reader 2: 1.33 ± 0.48 score for N- versus 3.65 ± 0.94 score for N+, p = 0.001, respectively). ROC curve analysis for lymph node discrimination showed an area under the curve of 0.68. A threshold value of 2 resulted in a sensitivity of 0.62 and a specificity of 0.71., Conclusion: Node-RADS score derived from staging CT shows only limited diagnostic accuracy to correctly predict nodal positivity in colon cancer. The interreader variability seems to be high and should question the clinical translation for this tumour entity., Competing Interests: Declarations. Ethics approval and consent to participate: This retrospective study was approved by our institutional ethics review board (Ethics Committee of the university of Leipzig EK: and the requirement for informed consent of patients was waived. Consent for publication: Not applicable. Competing interests: Authors have no conflict of interest., (© 2024. The Author(s).)

Background/aim: The recently published Node-Reporting and Data System (Node-RADS) can aid the characterization of lymph nodes in cross-sectional imaging. This study investigated the Node-RADS system in computed tomography (CT) to characterize lymph nodes in esophageal cancer., Patients and Methods: Overall, 126 patients (15 female, 11.9%) with a mean age of 62.1±10.4 years comprised the patient sample. All patients underwent resection with curative intent and the lymph nodes were histopathologically analyzed during clinical routine. For every patient, the locoregional lymph nodes were scored in accordance with the Node-RADS classification. For statistical analysis, receiver-operating characteristics (ROC) with area under the curve (AUC) were used to test for diagnostic accuracy; inter-reader variability was assessed with Cohen's kappa., Results: Overall, 54 patients were nodal positive (42.9%), 72 patients were nodal negative (57.1%). Inter-reader agreement was substantial for the overall Node-RADS scoring ([Formula: see text]=0.65, p<0.001). ROC curve analysis for lymph node discrimination (N0 versus N1-3) showed an AUC of 0.69 (95% confidence interval=0.59-0.79). A threshold score of more than 2 resulted in a sensitivity of 0.77 and a specificity of 0.55 for correctly predicting nodal positivity. Node-RADS 1 category had a malignancy rate of 30%, Node-RADS 2 of 14%, Node-RADS 3 of 81%, Node-RADS 4 of 90.1% and Node-RADS 5 of 86.5%., Conclusion: The Node-RADS score on staging CT is associated with the malignancy rate of lymph nodes in patients with EC with only moderate diagnostic accuracy. The inter-reader variability is moderate, which could pose difficulties for translation into clinical routine., (Copyright © 2025, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background: Body composition parameters provide relevant prognostic significance in critical care cohorts and cancer populations. Published results regarding polytrauma patients are inconclusive to date. The goal of this study was to analyse the role of body composition parameters in severely injured trauma patients., Methods: All consecutive patients requiring emergency tracheal intubation and mechanical ventilation before initial computed tomography (CT) at a level-1 trauma centre over a 12-year period (2008-2019) were reanalysed. The analysis included CT-derived body composition parameters based upon whole-body trauma CT as prognostic variables for 30-day mortality, intensive care unit length of stay (ICU LOS) and mechanical ventilation duration., Results: Four hundred seventy-two patients (75% male) with a median age of 49 years, median injury severity score of 26 and 30-day mortality rate of 22% (104 patients) met the inclusion criteria and were analysed. Regarding body composition parameters, 231 patients (49%) had visceral obesity, 75 patients had sarcopenia (16%) and 35 patients had sarcopenic obesity (7.4%). After adjustment for statistically significant univariable predictors age, body mass index, sarcopenic obesity, visceral obesity, American Society of Anesthesiologists classification ≥3, injury severity score and Glasgow Coma Scale ≤ 8 points, the Cox proportional hazard model identified sarcopenia as significant prognostic factor of 30-day mortality (hazard ratio 2.84; 95% confidence interval 1.38-5.85; P = 0.004), which was confirmed in Kaplan-Meier survival analysis (log-rank P = 0.006). In a subanalysis of 363 survivors, linear multivariable regression analysis revealed no significant associations of body composition parameters with ICU LOS and duration of mechanical ventilation., Conclusions: In a multivariable analysis of mechanically ventilated trauma patients, CT-defined sarcopenia was significantly associated with 30-day mortality whereas no associations of body composition parameters with ICU LOS and duration of mechanical ventilation were observed., (© 2024 The Author(s). Journal of Cachexia, Sarcopenia and Muscle published by Wiley Periodicals LLC.)

Background: This review discusses the quantitative assessment of tissue composition in the human body (body composition, BC) using radiological methods. Such analyses are gaining importance, in particular, for oncological and metabolic problems. The aim is to present the different methods and definitions in this field to a radiological readership in order to facilitate application and dissemination of BC methods. The main focus is on radiological cross-sectional imaging., Methods: The review is based on a recent literature search in the US National Library of Medicine catalog (pubmed.gov) using appropriate search terms (body composition, obesity, sarcopenia, osteopenia in conjunction with imaging and radiology, respectively), as well as our own work and experience, particularly with MRI- and CT-based analyses of abdominal fat compartments and muscle groups., Results and Conclusion: Key post-processing methods such as segmentation of tomographic datasets are now well established and used in numerous clinical disciplines, including bariatric surgery. Validated reference values are required for a reliable assessment of radiological measures, such as fatty liver or muscle. Artificial intelligence approaches (deep learning) already enable the automated segmentation of different tissues and compartments so that the extensive datasets can be processed in a time-efficient manner - in the case of so-called opportunistic screening, even retrospectively from diagnostic examinations. The availability of analysis tools and suitable datasets for AI training is considered a limitation., Key Points: · Radiological imaging methods are increasingly used to determine body composition (BC).. · BC parameters are usually quantitative and well reproducible.. · CT image data from routine clinical examinations can be used retrospectively for BC analysis.. · Prospectively, MRI examinations can be used to determine organ-specific BC parameters.. · Automated and in-depth analysis methods (deep learning or radiomics) appear to become important in the future.., Citation Format: · Linder N, Denecke T, Busse H. Body composition analysis by radiological imaging - methods, applications, and prospects. Fortschr Röntgenstr 2024; 196: 1046 - 1054., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Background: Texture analysis derived from computed tomography (CT) may provide clinically relevant imaging biomarkers associated with tumor histopathology. Perihilar cholangiocarcinoma is a malignant disease with an overall poor prognosis., Aims: The present study sought to elucidate possible associations between texture features derived from CT images with grading, tumor markers, and survival in extrahepatic, perihilar cholangiocarcinomas tumors., Methods: This retrospective study included 22 patients (10 females, 45%) with a mean age of 71.8 ± 8.7 years. Texture analysis was performed using the free available Mazda software. All tumors were histopathologically confirmed. Survival and clinical parameters were used as primary study outcomes., Results: In discrimination analysis, "S(1,1)SumVarnc" was statistically significantly different between patients with long-term survival and nonlong-term survival (mean 275.8 ± 32.6 vs. 239.7 ± 26.0, p = 0.01). The first-order parameter "skewness" was associated with the tumor marker "carcinoembryonic antigen" (CEA) (r = -0.7, p = 0.01). A statistically significant correlation of the texture parameter "S(5,0)SumVarnc" with tumor grading was identified (r = -0.6, p < 0.01). Several other texture features correlated with tumor markers CA-19-9 and AFP, as well as with T and N stage of tumors., Conclusion: Several texture features derived from CT images were associated with tumor characteristics and survival in patients with perihilar cholangiocarcinomas. CT texture features could be used as valuable novel imaging markers in clinical routine., (© 2024 The Author(s). Cancer Reports published by Wiley Periodicals LLC.)

Iatrogenic pneumothorax is a relevant complication of computed tomography (CT)-guided percutaneous lung biopsy. The aim of the present study was to analyze the prognostic significance of texture analysis, emphysema score and muscle mass derived from CT-imaging to predict postinterventional pneumothorax after CT-guided lung biopsy. Consecutive patients undergoing CT-guided percutaneous lung biopsy between 2012 and 2021 were analyzed. Multivariate logistic regression analysis included clinical risk factors and CT-imaging features to detect associations with pneumothorax development. Overall, 479 patients (178 females, mean age 65 ± 11.7 years) underwent CT-guided percutaneous lung biopsy of which 180 patients (37.5%) developed pneumothorax including 55 patients (11.5%) requiring chest tube placement. Risk factors associated with pneumothorax were chronic-obstructive pulmonary disease (COPD) (p = 0.03), age (p = 0.02), total lung capacity (p < 0.01) and residual volume (p = 0.01) as well as interventional parameters needle length inside the lung (p < 0.001), target lesion attached to pleura (p = 0.04), and intervention duration (p < 0.001). The combined model demonstrated a prediction accuracy of the occurrence of pneumothorax with an AUC of 0.78 [95%CI: 0.70-0.86] with a resulting sensitivity 0.80 and a specificity of 0.66. In conclusion, radiomics features of the target lesion and the lung lobe CT-emphysema score are predictive for the occurrence of pneumothorax and need for chest insertion after CT-guided lung biopsy., (© 2024. The Author(s).)

Purpose: Epicardial adipose tissue (EAT) detected by computed tomography (CT) is associated with morbidity and mortality in patients with COVID-19 and other critical care patient cohorts, whereas their prognostic relevance in trauma patients remains unclear. The present study explored associations with four potential short-term outcomes in trauma patients., Methods: All consecutive trauma patients requiring emergency tracheal intubation and mechanical ventilation before initial whole-body CT imaging at a level-1 trauma center over a 12-year period (2008-2019) were reanalyzed for this study. EAT was measured semiquantitatively in initial CT and analyzed regarding associations with 24-hour and 30-day mortality using Cox proportional hazard models. In survivors, associations of EAT with intensive care unit length of stay (ICU LOS) and mechanical ventilation duration were analyzed using linear regression analyses., Results: Four hundred fifty-five patients (74.7% male) with a median age of 49 years, and a median injury severity score (ISS) of 26 points were analyzed. In univariable analysis, EAT index was significantly associated with 24-hour and 30-day mortality (p = 0.007, and p = 0.013, respectively). After adjustment for significant predictors age, body mass index, and ISS, no significant associations were confirmed (p = 0.622, and p = 0.903, respectively). In a subanalysis of 353 survivors, EAT index was significantly associated with ICU LOS and mechanical ventilation duration in univariable analyses (p = 0.031, and p = 0.014, respectively), but not in multivariable analyses (p = 0.81 and p = 0.46, respectively)., Conclusion: EAT index was associated with short-term outcomes in severely injured trauma patients, which not remained significant in multivariable analysis, suggesting that its prognostic capability is limited., (© 2024. The Author(s).)

Objectives: Coronary artery calcifications detected by computed tomography (CT) provide prognostic relevance for vascular disorders and coronary heart disease, whereas their prognostic relevance in severely injured trauma patients remains unclear., Material and Methods: All consecutive trauma patients requiring emergency tracheal intubation before initial CT at a level-1 trauma center and admission to the intensive care unit (ICU) over a 12-year period (2008-2019) were reanalyzed. The Weston score, a semiquantitative method to quantify coronary calcifications, was evaluated as a prognostic variable based upon whole-body trauma CT analysis., Results: Four hundred fifty-eight patients (74.6% male) with a median age of 49 years, median injury severity score of 26 points, 24-h mortality rate of 7.6%, and 30-day mortality rate of 22.1% met the inclusion criteria and were analyzed. Coronary artery calcification was present in 214 patients (46.7%). After adjustment for confounding factors, the Weston score was an independent predictor for 24-h mortality (hazard ratio, HR 1.19, 95% confidence interval, CI 1.06-1.32, p = .002) and 30-day mortality (HR 1.09, 95% CI 1.01-1.17, p = .027). In a subanalysis of 357 survivors, the Weston score was significantly associated with ICU length of stay (LOS) (beta weight 0.89, 95% CI 0.3-1.47, p = .003) but not with mechanical ventilation duration (beta weight 0.05, 95% CI -0.2-0.63, p = .304)., Conclusion: CT-detected coronary calcification was a significant prognostic factor for 24-h- and 30-day-mortality in severely injured trauma patients requiring tracheal intubation, and influenced ICU LOS in survivors., (© 2024. The Author(s).)

Purpose: Contrast enhancement of the adrenal gland defined by computed tomography (CT) was previously analyzed as a prognostic factor for critically ill patients in various diseases. However, no study investigated this quantitative parameter in patients with acute mesenteric ischemia. Therefore, the aim of this study was to evaluate the prognostic value of the contrast enhancement of the adrenal glands in patients with clinically suspected AMI., Methods: All patients with clinically suspected AMI were retrospectively assessed between 2016 and 2020. All patients underwent surgical exploration after CT imaging. Overall, 134 patients (52 female patients, 38.8%) with a mean age of 69.2 ± 12.4 years were included into the present analysis. For all patients, the preoperative CT was used to calculate the contrast media enhancement of the adrenal glands and the spleen., Results: A total of 27 patients (18.5%) died within the first 24 h and over the following 30-day 94 patients (68.6%) died. There were statistically significant differences regarding the mean values for adrenal-to-spleen ratio for 24-h mortality (p = 0.001) and 30-day mortality (p = 0.004), whereas the radiodensity of the inferior vena cava and the radiodensity of the spleen was statistically significant between survivors and non-survivors after 30 days (p = 0.037 and p = 0.028, respectively). In Cox regression analysis, mean adrenal radiodensity was associated with 24-h mortality (HR 1.09, 95% CI 1.02-1.16, p = 0.01) but not with 30-day mortality (HR 1.03, 95% CI 0.99-1.07, p = 0.13)., Conclusion: The contrast media enhancement of the adrenal gland is associated with the 24-h and 30-day mortality in patients with AMI. However, the prognostic relevance for translation into clinical routine needs to be validated in other cohorts., (© 2024. The Author(s).)

To assess whether quantification of pulmonary perfusion defects on dual-energy computed tomography (DECT) relates to adverse events beyond clinical parameters and traditional embolus detection in patients with suspected pulmonary embolism (PE). We included consecutive patients who underwent DECT to rule out acute PE in 2018-2020 and recorded incident adverse events, defined as a composite of short-term (< 30 days) in-hospital all-cause mortality or admission to intensive care unit. Relative perfusion defect volume (PDV) was measured on DECT and indexed by total lung volume. PDV was then related to adverse events using logistic regressions adjusting for clinical parameters, clinical PE pre-test probability (Wells score), and visual PE burden on pulmonary angiography (Qanadli score). Among 136 included patients (63 [46%] females; age: 70 ± 14 years), 19/136 (14%) experienced adverse events during a median hospitalization of 7.5 (4-14) days. Overall, 7/19 (37%) events occurred in those without visible emboli but with measurable perfusion defects. An increase of PDV by one standard deviation was associated with over two times higher odds of adverse events (OR = 2.24; 95%CI:1.37-3.65; p = 0.001). This association remained significant after adjusting for the Wells and Qanadli scores (OR = 2.34; 95%CI:1.20-4.60; p = 0.013). PDV significantly increased the combined discriminatory capacity of Wells and Qanadli scores (AUC 0.76 vs. 0.80; p = 0.011 for difference). DECT-derived PDV may represent a prognostic imaging marker with incremental value beyond clinical and traditional imaging findings, improving risk stratification and aiding clinical management in patients with suspected PE., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Texture analysis derived from Computed tomography (CT) might be able to better characterize fluid collections undergoing CT-guided percutaneous drainage treatment. The present study tested, whether texture analysis can reflect microbiology results in fluid collections suspicious for septic focus., Methods: Overall, 320 patients with 402 fluid collections were included into this retrospective study. All fluid collections underwent CT-guided drainage treatment and were microbiologically evaluated. Clinically, serologically parameters and conventional imaging findings as well as textures features were included into the analysis. A new CT score was calculated based upon imaging features alone. Established CT scores were used as a reference standard., Results: The present score achieved a sensitivity of 0.78, a specificity of 0.69, area under curve (AUC 0.82). The present score and the score by Gnannt et al. (AUC 0.81) were both statistically better than the score by Radosa et al. (AUC 0.75). Several texture features were statistically significant between infected fluid collections and sterile fluid collections, but these features were not significantly better compared with conventional imaging findings., Conclusions: Texture analysis is not superior to conventional imaging findings for characterizing fluid collections. A novel score was calculated based upon imaging parameters alone with similar diagnostic accuracy compared to established scores using imaging and clinical features., (© 2021. The Author(s).)

To identify predictors of biopsy success and complications in CT-guided pancreas transplant (PTX) core biopsy. We retrospectively identified all CT fluoroscopy-guided PTX biopsies performed at our institution (2000-2017) and included 187 biopsies in 99 patients. Potential predictors related to patient characteristics (age, gender, body mass index (BMI), PTX age, PTX volume) and procedure characteristics (biopsy depth, needle size, access path, number of samples, interventionalist's experience) were correlated with biopsy success (sufficient tissue for histologic diagnosis) and the occurrence of complications. Biopsy success (72.2%) was more likely to be obtained in men [+25.3% (10.9, 39.7)] and when the intervention was performed by an experienced interventionalist [+27.2% (8.1, 46.2)]. Complications (5.9%) occurred more frequently in patients with higher PTX age [OR: 1.014 (1.002, 1.026)] and when many (3-4) tissue samples were obtained [+8.7% (-2.3, 19.7)]. Multivariable regression analysis confirmed male gender [OR: 3.741 (1.736, 8.059)] and high experience [OR: 2.923 (1.255, 6.808)] (biopsy success) as well as older PTX age [OR: 1.019 (1.002, 1.035)] and obtaining many samples [OR: 4.880 (1.240, 19.203)] (complications) as independent predictors. Our results suggest that CT-guided PTX biopsy should be performed by an experienced interventionalist to achieve higher success rates, and not more than two tissue samples should be obtained to reduce complications. Caution is in order in patients with older transplants because of higher complication rates., (© 2021 The Authors. Transplant International published by John Wiley & Sons Ltd on behalf of Steunstichting ESOT.)

Objective: The study's aim was to determine to what extent total visceral adipose tissue (VAT) volume (V VAT-T ) measured from segmented VAT areas (A VAT ) on all axial computed tomography (CT) sections (thickness of 5 mm) between the diaphragm and pelvic floor can be predicted by the A VAT of commonly selected landmark sections in patients with overweight or obesity., Methods: A total of 113 patients (31 females, 82 males) with images of full abdominopelvic coverage and proper image quality were included (BMI = 25.0-64.1 kg/m 2 , 29.5 ± 4.9 kg/m 2 ). Linear regression between A VAT and V VAT-T (reference) was used to determine approximate equations for VAT volume for all parameters (single sex, different anatomical landmarks or lumbar intervertebral disc spaces, one or five axial sections). Agreement was evaluated by the multivariate coefficient of determination and by the SD of the percentage difference (s d% ) between the estimated VAT volume on one or five sections and V VAT-T ., Results: The V VAT-T was 0.9 to 8.4 (3.8 ± 2.2) L for females and 2.7 to 11.7 (5.6 ± 2.1) L for males. Best agreement was found at L2-3 (s d%  = 14.3%-15.5%) for females and at L1-2 or L2-3 (11.7%-12.4%) for males. Agreement at the umbilicus or the femoral heads was poor (20.2%-57.9%). Segmentation of one or five sections was substantially faster (11/70 seconds) than whole-abdomen processing (15 minutes)., Conclusions: V VAT-T can be rapidly estimated by VAT segmentation of axial CT sections at sex-specific lumbar intervertebral disc spaces., (© 2020 The Obesity Society.)

Purpose: To quantify the occurrence of tumor seeding in computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) and to identify potential risk factors., Materials and Methods: CT-HDRBT is a minimally invasive therapeutic option for local ablation of unresectable tumors. The procedure involves CT-guided placement of an enclosed catheter and high-dose-rate brachytherapy using iridium-192. Transcutaneous puncture of a tumor with subsequent retraction of the applicator has the potential risk of tumor seeding along the puncture tract. A total of 1,765 consecutive CT-HDRBT procedures were performed at this center between 2006 and 2017 and were retrospectively analyzed. In addition, a distinction was made between whether the puncture tract was irradiated or not. Follow-up imaging datasets were evaluated for tumor seeding along the former puncture tracts. Descriptive and exploratory statistical analyses of the data were performed., Results: Tumor seeding was observed in 25 cases (25 of 1,765 cases [1.5%]). A total of 0.008 cases occurred per person-age. Patient age was identified as a potential risk factor with an odds ratio of 1.046 (95% confidence interval, 1.003-1.091; P = .04). There were no differences between whether the puncture tract was irradiated or not (P = .552)., Conclusions: Tumor seeding along the puncture tract can occur in CT-HDRBT but is rare., (Copyright © 2019 SIR. Published by Elsevier Inc. All rights reserved.)

Purpose: For local ablation of unresectable tumors, computed tomography-guided high-dose-rate brachytherapy (CT-HDRBT) is a minimally invasive therapeutic option involving CT-guided catheter placement and high-dose-rate irradiation with iridium-192. Possible complications are related to transcutaneous puncture, retraction of the applicator, and delivery of brachytherapy. To classify CT-HDRBT in comparison with other minimally invasive therapeutic options, it is essential to know the probability of complications and their risk factors. This study therefore aimed at quantifying the occurrence of complications in CT-HDRBT and identifying potential risk factors., Materials and Methods: Over a period of more than 10 years from 2006 to 2017, 1877 consecutive CT-HDRBTs were performed at our center and retrospectively analyzed. In 165 cases, CT-HDRBT was combined with transarterial (chemo-) embolization. Information on complications and potential risk factors was retrospectively retrieved from electronic documentation. Statistical analysis of the data was performed., Results: No complications occurred in 85.6% of the interventions. The most common complications were bleeding (5.6%), infection (2.0%), and prolonged pain (1.5%). Summarized diameter (defined as sum of maximum diameters in axial orientation) of treated tumor lesions (odds ratio 1.008; p < 0.001), target lesion site (odds ratio 1.132; p = 0.033), combined treatment (odds ratio 1.233; p = 0.038), and the presence of biliodigestive anastomosis (BDA) (odds ratio 1.824; p = 0.025) were identified as risk factors., Conclusions: CT-HDRBT is a safe minimally invasive therapeutic option. Summarized diameter of treated tumor lesions, target lesion site, combined treatment, and presence of BDA are risk factors for complications.

Background/aim: Thermal-ablative therapies are limited to tumors of 3-4 cm diameter. The purpose of this study was to evaluate the local tumor control (LTC) of CT-guided High-Dose-Rate-Brachytherapy (CT-HDRBT) for ablation of cholangiocarcinomas (CCA) ≥4 cm compared to smaller tumors., Patients and Methods: Sixty-one patients (tumors: 142, interventions: 91) were treated from March 2008 to January 2017. LTC, progression-free survival (PFS) and overall survival (OS) after first CT-HDRBT were identified for two subgroups (A:<4 cm, B:≥4 cm) and the influence of coverage and target-dose were evaluated. Log-Rank- and Mann-Whitney-U-Tests were performed for statistical analyses with p-values <0.05 considered as significant., Results: Better coverage was achieved for smaller tumors (A: 99.22-0.25%, B: 95.10-1.40%, p<0.001). LTC was better in subgroup A (A: 8, B: 6 months, p=0.006). Larger tumors (4-7 cm) with incomplete coverage showed the poorest LTC (p=0.032). There were no statistical significances in PFS (A: 5, B: 3 months, p=0.597) and OS (A:15.5; B:10.0 months, p=0.107)., Conclusion: CT-HDRBT is sufficient in CCA ≥4 cm, if full coverage with therapeutic doses can be achieved., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Aim: To evaluate different magnetic resonance imaging (MRI) sequences for diagnosis of pulmonary manifestations of cystic fibrosis (CF) in comparison to chest computed tomography (CT), including an extended outcome analysis., Materials and Methods: Twenty-eight patients with CF (15 male, 13 female, mean age 30.5±9.4 years) underwent CT and MRI of the lung. MRI (1.5 T) included different T2- and T1-weighted sequences: breath-hold HASTE (half Fourier acquisition single shot turbo spin echo) and VIBE (volumetric interpolated breath-hold examination, before and after contrast medium administration) sequences and respiratory-triggered PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) sequences with and without fat signal suppression, and perfusion imaging. CT and MRI images were evaluated by the modified Helbich and the Eichinger scoring systems. The clinical follow-up analysis assessed pulmonary exacerbations within 24 months., Results: The highest concordance to CT was achieved for the PROPELLER sequences without fat signal suppression (concordance correlation coefficient CCC of the overall modified Helbich score 0.93 and of the overall Eichinger score 0.93). The other sequences had the following concordance: PROPELLER with fat signal suppression (CCCs 0.91 and 0.92), HASTE (CCCs 0.87 and 0.89), VIBE (CCCs 0.84 and 0.85) sequences. In the outcome analysis, the combined MRI analysis of all five sequences and a specific MRI protocol (PROPELLER without fast signal suppression, VIBE sequences, perfusion imaging) reached similar correlations to the number of pulmonary exacerbations as the CT examinations., Conclusion: An optimum lung MRI protocol in patients with CF consists of PROPELLER sequences without fat signal suppression, VIBE sequences, and lung perfusion analysis to enable high diagnostic efficacy and outcome prediction., (Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Over the past 50 years, image-guided procedures have been established for a wide range of applications. The development and clinical translation of new treatment regimens necessitate the availability of suitable animal models. The juvenile Göttingen minipig presents a favourable profile as a model for human infants. However, no information can be found regarding the vascular system of juvenile minipigs in the literature. Such information is imperative for planning the accessibility of target structures by catheterization. We present here a complete mapping of the arterial system of the juvenile minipig based on contrast-enhanced computed tomography. Four female animals weighing 6.13 ± 0.72 kg were used for the analyses. Imaging was performed under anaesthesia, and the measurement of the vascular structures was performed independently by four investigators. Our dataset forms a basis for future interventional studies in juvenile minipigs, and enables planning and refinement of future experiments according to the 3R (replacement, reduction and refinement) principles of animal research.

Purpose: To evaluate efficacy of computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) of neuroendocrine liver metastases (NELM) with the goal of local tumor control (LTC)., Materials and Methods: This retrospective study included all patients with unresectable NELM treated with CT-guided HDRBT between January 2007 and April 2015. Magnetic resonance imaging follow-up was performed 6 weeks after ablation and then every 3 months. The primary endpoint was LTC. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and complications., Results: In 27 patients, 52 NELM were treated in 40 sessions. Three patients (11.1%) developed local progression with LTC of 1.9-36.8 months (median 10.4 months, mean 16.4 months). The remaining 24 patients (89.9%) had LTC of 3.1-106.1 months (median 31.3 months, mean 32.6 months). Progression or death was observed in 19 patients (70.4%) with PFS of 1.9-55.3 months (median 7.3 months, mean 16.3 months); the remaining 8 patients (29.6%) had PFS of 3.7-50.1 months (median 13.4 months, mean 19.6 months). Four patients (14.8%) died of causes unrelated to the procedure; their OS was 11.7-52.3 months (median 48.7 months, mean 40.4 months). OS was 4.2-106.1 months (median 30.3 months, mean 34.1 months) in the 23 surviving patients (85.2%). One patient experienced pain with nausea and vomiting, and 1 patient with biliodigestive anastomosis had a hepatic abscess., Conclusion: CT-guided HDRBT is a promising therapy with excellent LTC rates and low morbidity for patients with isolated/oligometastatic NELM., (Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of this study was to evaluate signs of right-sided heart dysfunction on staging computed tomography (CT) as indirect indicators of carcinoid heart disease., Patients and Methods: Patients with functionally active neuroendocrine neoplasm and different grades of tricuspid valve regurgitation (TR) were identified. Two readers independently reviewed contrast-enhanced staging CT performed within 90 days before or after echocardiography. Logistic regression and receiver operating analyses were used to asses the predictive value of right ventricle-left ventricle ratio (RV-LV ratio), ventricular septal bowing, retrograde contrast filling of the hepatic veins during contrast injection, and time to aortal enhancement greater than 100 Hounsfield units during bolus tracking for TR., Results: Forty-four examinations were evaluated (11 with TR = 0, 16 with TR = 1, 9 with TR = 2, and 8 with TR = 3). Right ventricle-LV ratio was found to predict TR less than or equal to 1 versus TR greater than 1 (P = 0.0188) and TR less than or equal to 1 versus TR equals 2 (P = 0.0082). A prolonged time to aortal enhancement greater than 100 Hounsfield units during bolus tracking predicted TR less than or equal to 1 versus TR greater than 1 (P = 0.0077). Area under the curve for RV-LV ratio was 0.86 when differentiating TR less than or equal to 1 versus TR equals 2. With a cutoff of 1.07, sensitivity was 0.89, and specificity was 0.72., Conclusions: In patients with functionally active neuroendocrine neoplasm, an RV-LV ratio of more than 1.07 predicted TR with a relatively high sensitivity and moderate specificity and thus could serve as an indicator of subclinical carcinoid heart disease on routine staging CT.

Pancreatic neuroendocrine neoplasms (pNEN) are rare malignancies arising from neuroendocrine cells of the pancreas. Functional tumors can present with specific clinical syndromes due to hormonal secretion. These tumors can present as incidental findings on imaging performed for unrelated purposes or they are diagnosed when workup is initiated in patients with specific syndromes or metastases. This article presents an overview of available imaging techniques focusing on computed tomography and magnetic resonance imaging. Recommendations regarding examination protocols are given. Typical imaging features of pNEN and metastases are described. Their potential value for the evaluation of prognosis as well as tumor response under treatment is discussed., (© The Foundation Acta Radiologica 2015.)

Objective: To evaluate whether magnetic resonance imaging (MRI) is effective as computed tomography (CT) in determining morphologic and functional pulmonary changes in patients with cystic fibrosis (CF) in association with multiple clinical parameters., Materials and Methods: Institutional review board approval and patient written informed consent were obtained. In this prospective study, 30 patients with CF (17 men and 13 women; mean (SD) age, 30.2 (9.2) years; range, 19-52 years) were included. Chest CT was acquired by unenhanced low-dose technique for clinical purposes. Lung MRI (1.5 T) comprised T2- and T1-weighted sequences before and after the application of 0.1-mmol·kg gadobutrol, also considering lung perfusion imaging. All CT and MR images were visually evaluated by using 2 different scoring systems: the modified Helbich and the Eichinger scores. Signal intensity of the peribronchial walls and detected mucus on T2-weighted images as well as signal enhancement of the peribronchial walls on contrast-enhanced T1-weighted sequences were additionally assessed on MRI. For the clinical evaluation, the pulmonary exacerbation rate, laboratory, and pulmonary functional parameters were determined., Results: The overall modified Helbich CT score had a mean (SD) of 15.3 (4.8) (range, 3-21) and median of 16.0 (interquartile range [IQR], 6.3). The overall modified Helbich MR score showed slightly, not significantly, lower values (Wilcoxon rank sum test and Student t test; P > 0.05): mean (SD) of 14.3 (4.7) (range, 3-20) and median of 15.0 (IQR, 7.3). Without assessment of perfusion, the overall Eichinger score resulted in the following values for CT vs MR examinations: mean (SD), 20.3 (7.2) (range, 4-31); and median, 21.0 (IQR, 9.5) vs mean (SD), 19.5 (7.1) (range, 4-33); and median, 20.0 (IQR, 9.0). All differences between CT and MR examinations were not significant (Wilcoxon rank sum tests and Student t tests; P > 0.05). In general, the correlations of the CT scores (overall and different imaging parameters) to the clinical parameters were slightly higher compared to the MRI scores. However, if all additional MRI parameters were integrated into the scoring systems, the correlations reached the values of the CT scores. The overall image quality was significantly higher for the CT examinations compared to the MRI sequences., Conclusions: One major diagnostic benefit of lung MRI in CF is the possible acquisition of several different morphologic and functional imaging features without the use of any radiation exposure. Lung MRI shows reliable associations with CT and clinical parameters, which suggests its implementation in CF for routine diagnosis, which would be particularly important in follow-up imaging over the long term.

Objectives: Transarterial chemoembolization (TACE) is established as bridging therapy of HCC listed for transplantation (LT). CT-guided brachytherapy (CTB) has not been evaluated as a bridging concept. We compared CTB and TACE for bridging before LT in HCC patients., Methods: Twelve patients with HCC received LT after CTB (minimal tumour dose, 15-20 Gy). Patients were matched (CTB:TACE, 1:2) by sex, age, number and size of lesions, and underlying liver disease with patients who received TACE before transplantation. Study endpoints were extent of necrosis at histopathology and recurrence rate after OLT., Results: There were no significant differences between the CTB and TACE groups regarding Child-Pugh category (p = 0.732), AFP (0.765), time on waiting list (p = 0.659), number (p = 0.698) and size (p = 0.853) of HCC lesions, fulfilment of Milan-criteria (p = 0.638), or previous liver-specific treatments. CTB achieved higher tumour necrosis rates than TACE (p = 0.018). The 1- and 3-year recurrence rate in the CTB group was 10 and 10 % vs. TACE, 14 and 30 % (p = 0.292)., Conclusions: Our data show comparable or even better response and post-LT recurrence rates of CTB compared to TACE for treating HCC in patients prior to LT. CTB should be further evaluated as an alternative bridging modality, especially for patients not suited for TACE., Key Points: • CT-guided interstitial brachytherapy (CTB) is a promising alternative to transarterial chemoembolization (TACE). • CTB instead of TACE is possible for bridging to liver transplantation in HCC patients. • HCC recurrence was not associated with CTB despite potential tumour seeding.

Objective: To investigate whether dose reduction via adaptive statistical iterative reconstruction (ASIR) affects image quality and diagnostic accuracy in neuroendocrine tumor (NET) staging., Methods: A total of 28 NET patients were enrolled in the study. Inclusion criteria were histologically proven NET and visible tumor in abdominal computed tomography (CT). In an intraindividual study design, the patients underwent a baseline CT (filtered back projection, FBP) and follow-up CT (ASIR 40%) using matched scan parameters. Image quality was assessed subjectively using a 5-grade scoring system and objectively by determining signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNRs). Applied volume computed tomography dose index (CTDIvol) of each scan was taken from the dose report., Results: ASIR 40% significantly reduced CTDIvol (10.17±3.06mGy [FBP], 6.34±2.25mGy [ASIR] (p<0.001) by 37.6% and significantly increased CNRs (complete tumor-to-liver, 2.76±1.87 [FBP], 3.2±2.32 [ASIR]) (p<0.05) (complete tumor-to-muscle, 2.74±2.67 [FBP], 4.31±4.61 [ASIR]) (p<0.05) compared to FBP. Subjective scoring revealed no significant changes for diagnostic confidence (5.0±0 [FBP], 5.0±0 [ASIR]), visibility of suspicious lesion (4.8±0.5 [FBP], 4.8±0.5 [ASIR]) and artifacts (5.0±0 [FBP], 5.0±0 [ASIR]). ASIR 40% significantly decreased scores for noise (4.3±0.6 [FBP], 4.0±0.8 [ASIR]) (p<0.05), contrast (4.4±0.6 [FBP], 4.1±0.8 [ASIR]) (p<0.001) and visibility of small structures (4.5±0.7 [FBP], 4.3±0.8 [ASIR]) (p<0.001)., Conclusion: In clinical practice ASIR can be used to reduce radiation dose without sacrificing image quality and diagnostic confidence in staging CT of NET patients. This may be beneficial for patients with frequent follow-up and significant cumulative radiation exposure., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Objectives: Evaluation of computed tomography (CT) and magnetic resonance imaging (MRI) for differentiation of pancreatic intraductal papillary mucinous neoplasm (IPMN) subtypes based on objective imaging criteria., Methods: Fifty-eight patients with 60 histologically confirmed IPMNs were included in this retrospective study. Eighty-three imaging studies (CT,n = 42; MRI,n = 41) were analysed by three independent blinded observers (O1-O3), using established imaging criteria to assess likelihood of malignancy (-5, very likely benign; 5, very likely malignant) and histological subtype (i.e., low-grade (LGD), moderate-grade (MGD), high-grade dysplasia (HGD), early invasive carcinoma (IPMC), solid carcinoma (CA) arising from IPMN)., Results: Forty-one benign (LGD IPMN,n = 20; MGD IPMN,n = 21) and 19 malignant (HGD IPMN,n = 3; IPMC,n = 6; solid CA,n = 10) IPMNs located in the main duct (n = 6), branch duct (n = 37), or both (n = 17) were evaluated. Overall accuracy of differentiation between benign and malignant IPMNs was 86/92 % (CT/MRI). Exclusion of overtly malignant cases (solid CA) resulted in overall accuracy of 83/90 % (CT/MRI). The presence of mural nodules and ductal lesion size ≥30 mm were significant indicators of malignancy (p = 0.02 and p < 0.001, respectively)., Conclusions: Invasive IPMN can be identified with high confidence and sensitivity using CT and MRI. The diagnostic problem that remains is the accurate radiological differentiation of premalignant and non-invasive subtypes., Key Points: • CT and MRI can differentiate benign from malignant forms of IPMN. • Identifying (pre)malignant histological IPMN subtypes by CT and MRI is difficult. • Overall, diagnostic performance with MRI was slightly (not significantly) superior to CT.

Purpose: The purpose of the present study was to evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) in patients with unresectable hepatocellular carcinoma (HCC)., Patients and Methods: Over a 6-year period, 98 patients with 212 unresectable HCC underwent CT-HDRBT applying a (192)Ir source at our institution. Magnetic resonance imaging (MRI) follow-up was performed 6 weeks after the intervention and then every 3 months. The primary endpoint was local tumor control (LTC); secondary endpoints included progression-free survival (PFS) and overall survival (OS)., Results: Patients were available for MRI evaluation for a mean follow-up of 23.1 months (range 4-64 months; median 20 months). Mean tumor diameter was 5 cm (range 1.8-12 cm). Eighteen of 212 (8.5 %) tumors showed local progression after a mean LTC of 21.1 months. In all, 67 patients (68.4 %) experienced distant tumor progression. The mean PFS was 15.2 months. Forty-six patients died during the follow-up period. Median OS was 29.2 months. Actuarial 1-, 2-, and 3-year OS rates were 80, 62, and 46 %, respectively., Conclusion: CT-HDRBT is an effective therapy to attain local tumor control in patients with unresectable HCC. Prospective randomized studies comparing CT-HDRBT with the standard treatments like Radiofrequency ablation (RFA) and chemoembolization (TACE) are mandatory.

Objective: To correctly display the left and right liver lobe separately on dynamic projection scintigraphy, it is essential to adjust the collimator to the angle of the plane between the two liver lobes. We propose an optimized protocol for separating left and right liver lobe in (99m)Tc-mebrofenin hepatobiliary scintigraphy in a hybrid SPECT-CT device. The protocol uses the inherent attenuation correction low-dose CT (AC-CT) for individually adjusting gamma camera head angulation. The results of this protocol are compared with hypothetical results based on previous MRI, fixed angle, and traditional frontal projection., Methods: The absolute and relative degrees of overlapping volume between left and right liver lobe parenchyma for frontal projection, 45° right anterior oblique (RAO) projection, RAO angulation based on previously acquired MRI, and RAO based on the AC-CT were measured in 14 patients who underwent (99m)Tc-mebrofenin hepatobiliary scintigraphy., Results: Relative degree of overlap was 31.3 ± 15.2 % for frontal projection, 8.2 ± 6.5 % for 45° RAO, 5.5 ± 3.5 % for RAO based on previous MRI, and 3.6 ± 2.5 % for RAO based on AC-CT. The relative overlap of RAO projections based on previous MRI was significantly lower than for frontal projection (p < 0.05). Use of the angle from the prior AC-CT, however, resulted in an even lower degree of overlap (p < 0.05)., Conclusions: Performing (99m)Tc-mebrofenin hepatobiliary scintigraphy using RAO detector alignment with an angle derived from a prior CT obtained in the SPECT-CT scanner can significantly reduce the degree of overlap between right and left liver lobe. If SPECT-CT is not available, previous CT or MRI or a fixed angle of 45° may be used.

Purpose: To evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) of unresectable colorectal liver metastases (CRLMs)., Materials and Methods: Retrospective analysis of all consecutive patients with unresectable CRLMs treated with CT-HDRBT between January 2008 and November 2012. Treatment was performed by CT-guided catheter placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed after 6 weeks and then every 3 months post-intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS)., Results: 80 heavily pretreated patients with 179 metastases were available for MRI evaluation for a mean follow-up time of 16.9 months. The mean tumor diameter was 28.5 mm (range: 8 - 107 mm). No major complications were observed. A total of 23 (12.9 %) local tumor progressions were observed. Lesions ≥ 4 cm in diameter showed significantly more local progression than smaller lesions (< 4 cm). 50 patients (62.5 %) experienced systemic tumor progression. The median TTP was 6 months. 28 (43 %) patients died during the follow-up period. The median OS after ablation was 18 months., Conclusion: CT-HDRBT is an effective technique for the treatment of unresectable CRLMs and warrants promising LTC rates compared to thermal ablative techniques. A combination with other local and systemic therapies should be evaluated in patients with lesions > 4 cm in diameter, in which higher progression rates are expected., Key Points: • CT-HDRBT enables a highly cytotoxic irradiation of colorectal liver metastases with simultaneous conservation of important neighboring structures (eg liver parenchyma, bile ducts and bowel)• The local tumor control rates obtained by CT-HDRBT in patients with colorectal liver metastases are promising, also compared to the local tumor control rates after RFA• Metastases with a diameter of 4 cm or abow, display a higher local progression rate after CT-HDRBT, therefor a combination therapy with other locoregional or systemic treatments should be investigated in prospective studies., (© Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: To retrospectively analyze the degree of artefacts in CT and MRI scans caused by coils and vascular plugs used for portal vein embolization (PVE)., Materials and Methods: All patients who underwent PVE between July 2011 and December 2012 and received either plug or coil embolization additional to particle embolization were retrospectively analyzed. Artefacts causes by embolization materials were measured in CT and MRI scans following PVE., Results: The sum of the artefact diameters caused from coils was significantly higher in CT (188.3 ± 26.1 mm) than in MRI T1 (50.5 ± 6.5 mm) or T2 imaging (39.5 ± 9.7 mm) (P<0.05). In MRI, the diameter in T1 and T2 sequences did not differ significantly (P=0.977). The sum of the artefact diameters from vascular plugs in MRI T1 sequences (62.5 ± 8.7 mm) was significantly higher than in CT (46.6 ± 4.8 mm; P<0.05) and MRI T2 sequences (52.8 ± 3.8 mm; P<0.05)., Conclusion: PVE with particles and vascular plug causes significantly fewer artefacts than PVE with particles and coils on CT scans following embolization, which can be important in the event of vascular complications or in follow-up scans, should the patient become unresectable., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Complete tumor resection is still the only potentially curative therapy option for patients with ductal adenocarcinoma of the pancreas. Surgical exploration is the gold standard for the determination of tumor resectability. Radiological resectability assessment is of great importance because many clearly unresectable cases can be identified preoperatively and it became essential for surgical planning. The evolving surgical and radiological techniques demand a continuous reappraisal of radiological criteria in resectability assessment. In the following, the criteria for resection planning are described along with surgical management and the role of radiology in some innovative surgical concepts is explained., (© Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: There are different therapeutic options in non-functional well to moderately differentiated (G1 and G2) pancreatic neuroendocrine tumors (pNET) with unresectable hepatic metastases including systemic chemotherapy and novel molecular targeted therapies. Treatment with somatostatin analogs (SSA) as antiproliferative agents is optional. At initial diagnosis watchful waiting until tumor progression is a well-established approach. Goal of this study was to evaluate imaging features as potential prognostic factors predicting early tumor progression in order to select patients that might benefit from an earlier initiation of medical treatment., Patients and Methods: In 44 patients we correlated tumor grade, chromogranin A (CgA) levels, treatment with SSA and imaging features of hepatic metastases on contrast-enhanced multiphase CT and MR imaging with time to tumor progression (TTP) according to RECIST 1.0., Results: In the total patient cohort none of the tested imaging features was found to be a statistically significant prognostic factor for TTP. Since treatment with SSA was associated with an increased TTP we also analyzed a subgroup of 30 patients not treated with SSA. In this subgroup of patients hypoenhancement of hepatic metastases during early contrast phases was found to be a negative prognostic factor for early tumor progression within 12 months (p=0.039). The other evaluated parameters including hepatic tumor load, number of metastases, and presence of regressive morphological changes did not reveal significant results., Conclusion: Hypovascularization of liver metastases from G1 and G2 pNET reflected by hypoenhancement during the early contrast phases seems to be associated with early tumor progression. In patients with hypoenhancing metastases repeated biopsy for reassessment of grading of these metastases, and early initiation of therapy should be considered., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To evaluate technical feasibility and clinical outcome of computed tomography-guided high-dose-rate-brachytherapy (CT-HDRBT) ablation of metastases adjacent to the liver hilum., Materials and Methods: Between November 2007 and May 2012, 32 consecutive patients with 34 metastases adjacent to the liver hilum (common bile duct or hepatic bifurcation ≤5 mm distance) were treated with CT-HDRBT. Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. MRI follow-up was performed 6 weeks and every 3 months post intervention. The primary endpoint was local tumor control (LTC); secondary endpoints included time to progression (TTP) and overall survival (OS)., Results: Patients were available for MRI evaluation for a mean follow-up time of 18.75 months (range: 3-56 months). Mean tumor diameter was 4.3 cm (range: 1.3-10.7 cm). One major complication was observed. Four (11.8%) local recurrences were observed after a local tumor control of 5, 8, 9 and 10 months, respectively. Twenty-two patients (68.75%) experienced a systemic tumor progression during the follow up period. Mean TTP was 12.9 months (range: 2-56 months). Nine patients died during the follow-up period. Median OS was 20.24 months., Conclusion: Minimally invasive CT-HDRBT is a safe and effective option also for unresectable liver metastases adjacent to the liver hilum that would have been untreatable by thermal ablation., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Objective: The objective of this study was to evaluate computed tomography (CT) findings in patients with sepsis with unknown inflammatory focus and acute respiratory distress syndrome., Methods: Acute respiratory distress syndrome findings on CT of 36 patients with sepsis were graded on a 6-point scale, and the percentage of affected lung was estimated. Resulting CT scores were correlated to intensive care scores and survival., Results: Forty-four percent of the patients died, revealing a significantly higher CT score than survivors (P = 0.01). Survivors showed larger areas of unaffected lung (P < 0.001), whereas patients with fatal outcome had more ground-glass opacities (P = 0.002; sensitivity, 73%; specificity, 57%) and traction bronchiectasis (P = 0.009; sensitivity, 54%; specificity, 68%). Pulmonary findings on CT did not allow discriminating between a pulmonary and extrapulmonary focus. No significant coherence between CT score and intensive care scores could be revealed., Conclusions: A CT scoring system based on pulmonary findings in patients with sepsis with acute respiratory distress syndrome comprises prognostic implications in terms of the patients' survival.

Aim: In combined positron emission tomography/computed tomography (PET/CT) of neuroendocrine neoplasms using (68)Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide ((68)Ga-DOTATOC), partial volume effects (PVEs) may occur in smaller lesions. This study determined the lesional cutoff size for the occurrence of PVEs in a clinical setting., Methods: Retrospective assessment of 51 PET/CT examinations (16-slice PET/CT device) for malignant PET foci was carried out. In all foci, the maximal standardized uptake value (SUVmax) and maximal lesion diameter on axial CT was documented. Determined SUVmax and lesional sizes were correlated via LOESS regression. In the resulting curve, the cutoff point for SUVmax size dependency was determined visually and mathematically using 2 approximating straight lines., Results: In 45 patients, 313 of 413 PET foci found were malignant, measurable on CT and had a roughly spherical geometry (SUVmax: 2.5-103.3, mean ± SD 20.5 ± 15.18; CT diameter: 5-103 mm, mean ± SD 21.8 ± 13.1 mm). The cutoff lesional size for the occurrence of PVEs was 20.4 mm by the mathematical approach and 25 mm by visual assessment., Conclusion: In (68)Ga-DOTATOC imaging, the clinical lesional size threshold is far larger than expected from systemic resolution only. Thus, tracer uptake quantification is only acceptable in sufficiently large lesions., (Copyright © 2013 S. Karger AG, Basel.)

Background: Intrahepatic recurrence after resection of intrahepatic or hilar cholangiocarcinoma represents a main reason for the poor prognosis of bile duct cancer. As no standard treatment has been established so far, the aim of this study was to analyse the safety and efficacy of computed tomography-guided high-dose rate brachytherapy (CT-HDRBT) as an alternative treatment in those patients., Methods: The outcomes of 10 patients, who had been treated at least once for recurrent cholangiocarcinoma by CT-HDRBT, were retrospectively analysed., Results: The median survival of all patients after primary liver resection was 85 months [95% confidence interval (CI) 68.129-101.871] with overall 1- and 5-year survival rates of 100% and 78.7%, respectively. After the occurrence of intrahepatic tumour recurrence, a total of 15 CT-HDRBT procedures were performed, alone or combined with other recurrence treatments, without any major complications according to the Society of Interventional Radiology classification. The 1-year and 5-year survival rates after recurrence treatment were 77.1% and 51.4%, respectively., Conclusions: CT-HDRBT represents a safe treatment option for patients with recurrent bile duct cancer. As a part of a multimodal concept, CT-HDRBT might lead to a prolongation of survival in selected patients but further studies are urgently needed to prove this concept., (© 2012 International Hepato-Pancreato-Biliary Association.)

Purpose: This study was designed to investigate the clinical outcome of patients with irresectable, intrahepatic cholangiocarcinoma (IHC) treated with computed tomography (CT)-guided HDR-brachytherapy (CT-HDRBT) for local tumor ablation., Method: Fifteen consecutive patients with histologically proven cholangiocarcinoma were selected for this retrospective study. Patients were treated by high-dose-rate internal brachytherapy (HDRBT) using an Iridium-192 source in afterloading technique through CT-guided percutaneous placed catheters. A total of 27 brachytherapy treatments were performed in these patients between 2006 and 2009. Median tumor enclosing target dose was 20 Gy, and mean target volume of the radiated tumors was 131 (±90) ml (range, 10-257 ml). Follow-up consisted of clinical visits and magnetic resonance imaging of the liver every third month. Statistical evaluation included survival analysis using the Kaplan-Meier method., Results: After a median follow-up of 18 (range, 1-27) months after local ablation, 6 of the 15 patients are still alive; 4 of them did not get further chemotherapy and are regarded as disease-free. The reached median local tumor control was 10 months; median local tumor control, including repetitive local ablation, was 11 months. Median survival after local ablation was 14 months and after primary diagnosis 21 months., Conclusion: In view of current clinical data on the clinical outcome of cholangiocarcinoma, locally ablative treatment with CT-HDRBT represents a promising and safe technique for patients who are not eligible for tumor resection.

Purpose: To analyze initial experience with computed tomography-guided high-dose-rate brachytherapy (CT-HDRBT) ablation of breast cancer liver metastases (BCLM)., Materials and Methods: Between January 2008 and December 2010, 37 consecutive women with 80 liver metastases were treated with CT-HDRBT in 56 sessions. Mean age was 58.6 years (range, 34-83 y). Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. The mean radiation dose was 18.57 Gy (standard deviation 2.27). Tumor response was evaluated by gadoxetic acid-enhanced liver magnetic resonance (MR) imaging performed before treatment, 6 weeks after treatment, and every 3 months thereafter., Results: Two patients were lost to follow-up; the remaining 35 patients were available for MR imaging evaluation for a mean follow-up time of 11.6 months (range 3-32 mo). Mean tumor diameter was 25.5 mm (range 8-74 mm). Two (2.6%) local recurrences were observed after local tumor control for 10 months and 12 months. Both local progressions were successfully retreated. Distant tumor progression (new metastases or enlargement of nontreated metastases) occurred during the follow-up period in 11 (31.4%) patients. Seven (20%) patients died during the follow-up period. Overall survival ranged from 3-39 months (median 18 months)., Conclusions: CT-HDRBT is a safe and effective ablative therapy, providing a high rate of local tumor control in patients with BCLM., (Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the safety and efficacy of CT-guided high-dose brachytherapy (CT-HDRBT) ablation of primary and metastatic lung tumors., Materials and Methods: Between November 2007 and May 2010, all consecutive patients with primary or metastatic lung tumors, unsuitable for surgery, were treated with CT-HDRBT. Imaging follow-up after treatment was performed with contrast-enhanced CT at 6 weeks, 3 months and every 6 months after the procedure. The endpoints of the study were local tumor control and time to progression. The Kaplan-Meier method was used to estimate survival functions and local tumor progression rates., Results: 34 procedures were carried out on 33 lesions in 22 patients. The mean diameter of the tumors was 33.3 mm (SD = 20.4). The first contrast-enhanced CT showed that complete ablation was achieved in all lesions. The mean minimal tumor enclosing dose was 18.9 Gy (SD = 2). Three patients developed a pneumothorax after the procedure. The mean follow-up time was 13.7 (3 - 29) months. 2 of 32 lesions (6.25 %) developed a local tumor progression. 8 patients (36.3 %) developed a distant tumor progression. After 17.7 months, 13 patients were alive and 9 patients had died., Conclusion: CT-HDRBT ablation is a safe and attractive treatment option for patients with lung malignancies and allows targeted destruction of tumor tissue with simultaneous preservation of important lung structures. Furthermore, CT-HDRBT is independent of the size of the lesion and its location within the lung parenchyma., (© Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: The purpose of this study was to retrospectively evaluate whether computed tomography (CT) findings have prognostic value for the prediction of mortality and severity of the clinical course in patients presenting with early stage of acute respiratory distress syndrome (ARDS) due to swine-origin influenza A (S-OIV)., Materials and Methods: Chest CT (16-/64-row multidetector CT) of 23 patients (of whom 9 patients died) were retrospectively reviewed by three independent blinded observers. The CT findings were graded on a 3-point scale (1: normal attenuation, 2: ground-glass attenuation, 3: consolidation). The extent of each abnormality was determined by visually estimating the percentage (to the nearest 10%) of the affected lung parenchyma in each zone and multiplied by the CT-score described above., Results: All patients presented with a mixture of bilateral patchy consolidations and ground glass opacities. Spearman rank correlation in evaluation of the presence and extent of lung abnormalities by the three different observers was good (correlation coefficient, 0.876-0.922; p < 0.001). The overall CT-score in survivors (mean, 96.0 (± 26.2); range, 53-158) was significantly lower than that in non-survivors (mean, 116.2 (± 14.0); range, 101-139). ROC analysis revealed an area under curve of 0.79 (p = 0.021) for the CT score with an optimal cutoff value of a CT-score of 100 for prediction of survival, with a sensitivity of 100% and a specificity of 64% (accuracy, 78%). For this optimal cutoff, Kaplan-Meier estimator showed a significant difference for the survival ratio (p = 0.011)., Conclusion: In patients with severe ARDS due to S-OIV-infection, the CT-score has a prognostic value in the prediction of mortality., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Gastroenteropancreatic neuroendocrine tumors and their metastases have an inconsistent appearance with only a small percentage of lesions appearing as cystic masses in computed tomography (CT) and magnetic resonance imaging (MRI) and can therefore be mistaken as benign or infectious lesions, leading to a false diagnosis with delayed and inadequate treatment. We report a patient with upper abdominal pain lasting for several months, caused by a huge cystic neuroendocrine carcinoma of the liver which was mistakenly interpreted as an echinococcus cyst and present the findings in the initial CT and the subsequently performed MRI under application of hepatocyte specific contrast material, which led to distinct differential diagnoses and therefore had a capacious impact on the therapeutic strategy.

Aim: Hepatic resection for hepatic ovarian cancer metastases remains controversial. The purpose of this study was to evaluate the clinical outcome of CT-guided high dose rate brachytherapy (CT-HDRBT) for minimally invasive cytoreduction of isolated metachronous ovarian cancer metastases to the liver., Patients and Methods: Seven patients with 12 isolated ovarian cancer metastases to the liver were treated with CT-HDRBT. To evaluate tumor response a gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced liver MRI was performed before, six weeks after and every third month after treatment., Results: The mean MRI-follow-up period was 15.4 months. Tumors ranged from 13 to 120 mm in diameter. Complete ablation was achieved for all lesions. No complications occurred. No local progression was observed in any of the included patients. Overall survival was 100% after 12 months. Two patients died after 14 and 25 months, respectively., Conclusion: CT-HDRBT is a safe and valid technique for performing minimally invasive cytoreduction of metachronous isolated liver metastases from ovarian cancer.

Purpose: To evaluate the accuracy of 64-row-multidetector computed tomography (MDCT) with different slice thickness (0.625 vs. 1.25 mm) in assessing the cerebellar arteries., Materials and Methods: A total of 21 consecutive patients who underwent computed tomography angiography (CTA) of the cervicocranial arteries (64-row MDCT; slice thickness, 0.625 mm) because of suspicion of cerebral ischemia were enrolled retrospectively. The MDCT data set was secondarily reconstructed to a slice thickness of 1.25 mm. The examinations were reviewed by three independent blinded observers. Recorded parameters for reconstructed slice thicknesses of 0.625 compared to 1.25 mm were visualization and edge enhancement (based on a developed phantom reference model) of the cerebellar arteries including anterior and posterior inferior cerebellar arteries and the superior cerebellar artery., Results: With 0.625-mm slices, significantly more vessel segments were visualized and edge enhancement was superior compared to 1.25-mm slices by the three readers, and a significant difference for the interaction between vessel segments and the slice thickness was found (P<.001). Furthermore, for a slice thickness of 1.25 mm, there was a significant difference in visualization (P=.0042) and edge enhancement (P=.0015) of vessel segments between the three readers, whereas for thinner slices (0.625 mm), no significant differences were found (P=.412, P=.465)., Conclusions: MDCT with slice thickness of 0.625 mm is superior to 1.25 mm reconstructed slice thickness regarding the visualization of cerebellar arteries, representative for smallest assessable arteries in CTA. This is paralleled by a sharper edge enhancement of the vessel contours resulting from a reduced partial volume effect. Conclusively, cranial CTA protocols should be routinely optimized to generate submillimeter slices for diagnostic purposes and digital storage as additional diagnostic value can be expected., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Unlabelled: The diagnostic value of neuroendocrine tumor (NET) imaging using PET with integrated CT is dependent on both components. This retrospective study assessed the value of the single CT phases of a triple-phase (early arterial, portal-venous inflow, and venous) CT protocol in comparison to (68)Ga-DOTATOC PET in a masked reading., Methods: (68)Ga-DOTATOC PET/CT examinations from 51 patients with known or suspected NET were included. Two readers assessed the data of PET and each of the 3 CT phases for NET lesions independently (using a 3-point score: 1 = benign, 2 = indeterminate, and 3 = malignant) and by consensus (using binary benign/malignant interpretation only). Only lesions within the field of the abdominal scan were evaluated. Clinical and imaging follow-up, histopathology (if available), and the decision of an interdisciplinary truth-panel served as a standard of reference. In addition to the calculation of standard statistical parameters (including general linear mixed models), interobserver reliability was estimated (Cohen's κ)., Results: Of 510 abdominal lesions observed, 354 were classified as malignant. Sensitivity was 77.1% for combined triple-phase CT, 53.4% for arterial CT, 66.1% for portal-venous CT, 66.9% for venous CT, and 72.8% for PET. The respective specificities were 85.3%, 92.9%, 92.3%, 89.7%, and 97.4%, and the respective accuracies were 79.6%, 65.5%, 74.1%, 73.9%, and 80.4%. Although arterial CT was found to be inferior to PET, portal-venous CT, and venous CT (P < 0.001), the differences between the other scans were not significant. Detection was exclusively by PET for 16.1% of lesions, by triple-phase CT for 20.3%, by arterial CT for 0.5%, by portal-venous CT for 3.9%, and by venous CT for 3.9%. Regarding interobserver reliability, the κ-value was 0.768 for PET, 0.391 for triple-phase CT, 0.577 for arterial CT, 0.583 for portal-venous CT, and 0.482 for venous CT., Conclusion: No CT phase can be omitted in NET imaging, and the triple-phase protocol continues to be strongly recommended also for PET/CT.

Objective: To assess the possible extent of dose reduction for low-dose computed tomography (CT) in the detection of body-packing (ingested drug packets) as an alternative to plain radiographs in an animal model., Materials and Methods: Twelve packets containing cocaine (purity >80%) were introduced into the intestine of an experimental animal (crossbred pig), which was then repeatedly examined by abdominal CT with stepwise dose reduction (tube voltage, 80 kV; tube current, 10-350 mA). Three blinded readers independently evaluated the CT datasets starting with the lowest tube current and noted the numbers of packets detected at the different tube currents used. In addition, 1 experienced reader determined the number of packets detectable on plain abdominal radiographs and ultrasound., Results: The threshold for correct identification of all 12 drug packets was 100 mA for reader 1 and 125 mA for readers 2 and 3. Above these thresholds all 3 readers consistently identified all 12 packets. The effective dose of a low-dose CT scan with 125 mA (including scout view) was 1.0 mSv, which was below that of 2 conventional abdominal radiographs (1.2 mSv). The reader interpreting the conventional radiographs identified a total of 9 drug packets and detected 8 packets by abdominal ultrasound., Conclusions: Extensive dose reduction makes low-dose CT a valuable alternative imaging modality for the examination of suspected body-packers and might replace conventional abdominal radiographs as the first-line imaging modality., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: preoperative assessment of pancreatic masses is still challenging as regards the characterization and assessment of irresectability. The opportunities of modern multidetector computed tomography (MDCT) with image postprocessing can be expected to enhance the diagnostic performance if accurate criteria are elaborated., Purpose: to estimate the accuracy of MDCT and multiplanar image reconstructions with the use of standardized imaging criteria for preoperative evaluation of pancreatic masses with respect to irresectability., Material and Methods: a total of 105 consecutive patients who underwent exploratory laparoscopy or pancreatic resection and had preoperative 3-phase MDCT (4-64 rows) were enrolled retrospectively. First, transverse sections and secondly additional 3Ds were reviewed by two independent blinded observers (O1/O2). Preoperative imaging findings were correlated with intraoperative and histopathologic results., Results: among all 105 patients, 70 malignant pancreatic tumors and 35 benign pancreatic diseases were found (accuracy of 93% for O1 and 91% for O2). For arterial tumor invasion, receiver operator characteristic (ROC) analysis (values averaged from the results of O1 and O2) revealed an area under the curve (AUC) of 0.931 for transverse sections and 0.986 for 3Ds. Regarding irresectability, positive predictive values were 97% (with 3Ds, 97%) for O1/O2; negative predictive values were 84% (with 3Ds, 89%) for O1 and 86% (with 3Ds, 91%) for O2., Conclusion: MDCT with 3Ds was highly accurate for evaluation and assessment of irresectability criteria in patients with pancreatic masses. However, due to the limited specificity regarding arterial tumor infiltration, the indication for surgical exploration should be made generously in case of inconclusive findings.

Purpose: To determine the additional value of fluorodeoxyglucose-positron emission tomography (PET) for clinical target volume definition in the planning of computed tomography (CT)-guided interstitial brachytherapy for liver metastases., Patients and Methods: A total of 19 patients with liver metastases from colorectal cancer treated in 25 sessions were included in the present study. All patients had undergone fluorodeoxyglucose-PET for patient evaluation before interstitial CT-guided brachytherapy. A contrast-enhanced CT scan of the upper abdomen was obtained for radiation planning. The clinical target volume (CTV) was defined by a radiation oncologist and radiologist. After registration of the CT scan with the PET data set, the target volume was defined again using the fusion images., Results: PET revealed one additional liver lesion that was not visible on CT. The median CT-CTV (defined using CT and magnetic resonance imaging) was 68 cm(3) (range 4-260). The PET/CT-CTV (median, 78 cm(3); range, 4-273) was significantly larger, with a median gain of 24.5% (interquartile range, 2.1-71.5%; p = .022). An increased CTV was observed in 15 cases and a decrease in 6; in 4 cases, the CT-CTV and PET/CT-CTV were equal. Incomplete dose coverage of PET/CT-CTVs was indicative of early local progression (p = .004); however, CT-based radiation plans did not show significant differences in the local control rates when stratified by dose coverage., Conclusion: Retrospective implementation of fluorodeoxyglucose-PET for CTV specification for CT-guided brachytherapy for colorectal liver metastases revealed a significant change in the CTVs. Additional PET-positive tumor regions with incomplete dose coverage could explain unexpected early local progression., (Copyright 2010 Elsevier Inc. All rights reserved.)

Purpose: Since meningiomas show a high expression of somatostatin receptor subtype 2, PET with (68)Ga-DOTATOC was proposed as an additional imaging modality beside CT and MRI for planning radiotherapy. We investigated the input of (68)Ga-DOTATOC-PET/CT on the definition of the "gross tumour volume" (GTV) in meningiomas, in order to assess the potential value of this method., Methods: Prior to radiotherapy, 42 patients with meningiomas (26 f, 16 m, mean age 55) underwent MRI and (68)Ga-DOTATOC-PET/CT examinations., History: operated n = 24, radiotherapy n = 1, operation and radiotherapy n = 8, no treatment n = 9. PET/CT and MRI data were co-registered using a BrainLAB workstation. For comparison, the GTV was defined first under consideration of CT and MRI data, then using PET data., Results: 3/42 patients were excluded from the analysis (two with negative PET results, one with an extensive tumour, not precisely delineable by MRI or PET/CT). The average GTV(CT/MRI) was 22(+/-19)cm(3); GTV(PET) was 23(+/-20)cm(3). Additional GTV, obtained as a result of PET was 9(+/-10)cm(3) and was observed in patients with osseous infiltration. In some pre-treated patients there were intratumoural areas (as identified in CT/MRI) without SR-expression (7(+/-11)cm(3)). Common GTV as obtained by both CT/MRI and PET was 15(+/-14)cm(3). The mean bi-directional difference between the GTV(CT/MRI) and GTV(PET) accounted to 16(+/-15)cm(3) (93%, p < 0.001). In a subgroup of seven patients with multiple meningiomas, PET showed a total of 19 lesions; nine of them were not recognizable by CT or MRI., Conclusion: (68)Ga-DOTATOC-PET enables delineation of SR-positive meningiomas and delivers additional information to both CT and MRI regarding the planning of stereotactic radiotherapy. The acquisition on a PET/CT scanner helps to estimate the relation of PET findings to anatomical structures and is especially useful for detection of osseous infiltration. (68)Ga-DOTATOC-PET also allows detection of additional lesions in patients with multiple meningiomas.