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1.
Cancer Immunol Immunother ; 70(4): 893-907, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33006650

ABSTRACT

Thermal ablative therapies are standard treatments for localized hepatocellular carcinoma (HCC). In addition to local tumor destruction, ablation leads to abscopal effects in distant lesions most likely mediated by an anti-tumor immune response. Although microwave ablation (MWA) is increasingly substituting other ablative techniques, its systemic immunostimulatory effects are poorly studied. We analyzed tumor-specific immune responses in peripheral blood of HCC patients after thermal ablation with regard to T cell responses and disease outcome. While comprehensive flow cytometric analyses in sequential samples of a prospective patient cohort (n = 23) demonstrated only moderate effects of MWA on circulating immune cell subsets, fluorospot analyses of specific T cell responses against seven tumor-associated antigens (TTAs) revealed de-novo or enhanced tumor-specific immune responses in 30% of patients. This anti-tumor immune response was related to tumor control as Interferon-y and Interleukin-5 T cell responses against TAAs were more frequent in patients with a long-time remission (> 1 year) after MWA (7/16) compared to patients suffering from an early relapse (0/13 patients) and presence of tumor-specific T cell response (IFN-y and/or IL-5) was associated to longer progression-free survival (27.5 vs. 10.0 months). Digital image analysis of immunohistochemically stained archival HCC samples (n = 18) of patients receiving combined MWA and resection revealed a superior disease-free survival of patients with high T cell abundance at the time of thermal ablation (37.4 vs. 13.1 months). Our data demonstrates remarkable immune-related effects of MWA in HCC patients and provides additional evidence for a combination of local ablation and immunotherapy in this challenging disease.


Subject(s)
Carcinoma, Hepatocellular/immunology , Catheter Ablation/methods , Immunity/immunology , Liver Neoplasms/immunology , Microwaves/therapeutic use , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Female , Follow-Up Studies , Humans , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Prognosis , Prospective Studies , Survival Rate
2.
Eur Radiol ; 30(7): 3968-3976, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32125516

ABSTRACT

OBJECTIVES: Peritoneal carcinomatosis (PC) is a prognostically relevant metastatic disease which may be difficult to depict in postoperative patients, particularly in early stages. This study aimed to determine whether PC could be diagnosed more accurately when using a combination of spectral detector CT (SDCT)-derived conventional images (CI) and iodine overlay images (IO) compared with CI only. METHODS: Thirty patients with PC and 30 patients with benign peritoneal alterations (BPA) who underwent portal-venous abdominal SDCT were included. Four radiologists determined the presence/absence of PC for each patient and assessed lesion conspicuity, diagnostic certainty, and image quality using 5-point Likert scales. Subjective assessment was conducted in two sessions comprising solely CI and CI/IO between which a latency of 6 weeks was set. Iodine uptake and HU attenuation were determined ROI-based to analyze quantitative differentiation of PC/BPA. RESULTS: Specificity for PC was significantly higher when using CI/IO compared with using CI only (0.86 vs. 0.78, p ≤ 0.05), while sensitivity was comparable (0.79 vs. 0.81, p = 1). In postoperative patients, the increase in specificity was the highest (0.93 vs. 0.80, p ≤ 0.05). Lesion conspicuity was rated higher in CI/IO (4 (3-5)) compared with that in CI only (3 (3-4); p ≤ 0.05). Diagnostic certainty was comparable (both 4 (3-5); p = 0.5). CI/IO received the highest rating for overall image quality and assessability (CI/IO 5 (4-5) vs. CI 4 (4-4) vs. IO 4 (3-4); p ≤ 0.05). Area under the receiver operating characteristics curve (AUC) for quantitative differentiation between PC and BPA was higher for iodine (AUCIodine = 0.95, AUCHU = 0.90). CONCLUSIONS: Compared with CI, combination of CI/IO improves specificity in the assessment of peritoneal carcinomatosis at comparable sensitivity, particularly in postoperative patients. KEY POINTS: • Combination of iodine overlays and conventional images improves specificity when assessing patients with peritoneal carcinomatosis at comparable sensitivity. • Particularly in postsurgical patients, iodine overlays could help to avoid false-positive diagnosis of peritoneal disease. • Iodine overlays alone provided inferior image quality and assessability than conventional images, while the combination of both received the highest ratings. Iodine overlays should therefore be used in addition to and not as a substitute for conventional images.


Subject(s)
Iodine/metabolism , Peritoneal Neoplasms/diagnosis , Peritoneum/diagnostic imaging , Tomography, X-Ray Computed/methods , Aged , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Portal Vein , ROC Curve
3.
Eur Radiol ; 29(4): 2098-2106, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30324387

ABSTRACT

OBJECTIVE: To comprehensively assess precision, reproducibility, and repeatability of iodine maps from spectral detector CT (SDCT) in a phantom and in patients with repetitive examination of the abdomen. METHODS: Seventy-seven patients who underwent examination two (n = 52) or three (n = 25) times according to clinical indications were included in this IRB-approved, retrospective study. The anthropomorphic liver phantom and all patients were scanned with a standardized protocol (SSDE in patients 15.8 mGy). In patients, i.v. contrast was administered and portal venous images were acquired using bolus-tracking technique. The phantom was scanned three times at three time points; in one acquisition, image reconstruction was repeated three times. Region of interest (ROI) were placed automatically (phantom) or manually (patients) in the liver parenchyma (mimic) and the portal vein; attenuation in conventional images (CI [HU]) and iodine map concentrations (IM [mg/ml]) were recorded. The coefficient of variation (CV [%]) was used to compare between repetitive acquisitions. If present, additional ROI were placed in cysts (n = 29) and hemangioma (n = 29). RESULTS: Differences throughout all phantom examinations were < 2%. In patients, differences between two examinations were higher (CV for CI/IM: portal vein, 2.5%/3.2%; liver parenchyma, -0.5%/-3.0% for CI/IM). In 80% of patients, these differences were within a ± 20% limit. Differences in benign liver lesions were even higher (68% and 38%, for CI and IM, respectively). CONCLUSIONS: Iodine maps from SDCT allow for reliable quantification of iodine content in phantoms; while in patients, rather large differences between repetitive examinations are likely due to differences in biological distribution. This underlines the need for careful clinical interpretation and further protocol optimization. KEY POINTS: • Spectral detector computed tomography allows for reliable quantification of iodine in phantoms. • In patients, the offset between repetitive examinations varies by 20%, likely due to differences in biological distribution. • Clinically, iodine maps should be interpreted with caution and should take the intra-individual variability of iodine distribution over time into account.


Subject(s)
Image Processing, Computer-Assisted/methods , Iodine/analysis , Liver Diseases/diagnosis , Liver/chemistry , Phantoms, Imaging , Tomography, X-Ray Computed/methods , Female , Humans , Liver Diseases/metabolism , Male , Middle Aged , Reproducibility of Results , Retrospective Studies
4.
Eur J Haematol ; 100(4): 383-385, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29140544

ABSTRACT

Cryptosporidium infection is a rare cause of enterocolitis. In immunocompromised patients, cryptosporidiosis may lead to debilitating and life-threatening diarrhea and malabsorption, occasionally with multi-organ involvement. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) requires long-term immunosuppressive therapy, while cellular immunity is usually compromised due to intensive conditioning chemotherapy. Diarrhea in patients who underwent allo-HSCT may be a sign of an infection, but can also be the result of intestinal graft-versus-host disease (GvHD). Here, we describe the case of a patient who developed severe diarrhea following allo-HSCT for relapsed T-lymphoblastic lymphoma. Initially, GvHD was suspected and treatment was initiated accordingly. However, a colon biopsy showed signs of cryptosporide oocysts alongside only low-grade GvHD. Following molecular confirmation of the diagnosis of cryptosporidiosis, an intensive treatment regimen was started. Despite the severe clinical course, the patient recovered and was discharged with only residual symptoms.


Subject(s)
Cryptosporidiosis/etiology , Hematopoietic Stem Cell Transplantation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Adult , Antiparasitic Agents/therapeutic use , Colon/microbiology , Colon/pathology , Cryptosporidiosis/diagnosis , Cryptosporidiosis/drug therapy , Cryptosporidium/genetics , Female , Graft vs Host Disease/etiology , Graft vs Host Disease/prevention & control , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Polymerase Chain Reaction , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Recurrence , Transplantation, Homologous , Treatment Outcome
5.
Acta Radiol ; 59(12): 1458-1465, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29569933

ABSTRACT

BACKGROUND: A novel, multi-energy, dual-layer spectral detector computed tomography (SDCT) is commercially available now with the vendor's claim that it yields the same or better quality of polychromatic, conventional CT images like modern single-energy CT scanners without any radiation dose penalty. PURPOSE: To intra-individually compare the quality of conventional polychromatic CT images acquired with a dual-layer spectral detector (SDCT) and the latest generation 128-row single-energy-detector (CT128) from the same manufacturer. MATERIAL AND METHODS: Fifty patients underwent portal-venous phase, thoracic-abdominal CT scans with the SDCT and prior CT128 imaging. The SDCT scanning protocol was adapted to yield a similar estimated dose length product (DLP) as the CT128. Patient dose optimization by automatic tube current modulation and CT image reconstruction with a state-of-the-art iterative algorithm were identical on both scanners. CT image contrast-to-noise ratio (CNR) was compared between the SDCT and CT128 in different anatomic structures. Image quality and noise were assessed independently by two readers with 5-point-Likert-scales. Volume CT dose index (CTDIvol), and DLP were recorded and normalized to 68 cm acquisition length (DLP68). RESULTS: The SDCT yielded higher mean CNR values of 30.0% ± 2.0% (26.4-32.5%) in all anatomic structures ( P < 0.001) and excellent scores for qualitative parameters surpassing the CT128 (all P < 0.0001) with substantial inter-rater agreement (κ ≥ 0.801). Despite adapted scan protocols the SDCT yielded lower values for CTDIvol (-10.1 ± 12.8%), DLP (-13.1 ± 13.9%), and DLP68 (-15.3 ± 16.9%) than the CT128 (all P < 0.0001). CONCLUSION: The SDCT scanner yielded better CT image quality compared to the CT128 and lower radiation dose parameters.


Subject(s)
Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted/methods , Radiography, Abdominal/methods , Radiography, Thoracic/methods , Tomography, X-Ray Computed/instrumentation , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Image Processing, Computer-Assisted/methods , Male , Middle Aged , Reproducibility of Results
6.
Eur Radiol ; 27(9): 3625-3634, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28168371

ABSTRACT

OBJECTIVES: The objective of this study was to assess the influence of an iterative CT reconstruction algorithm (IA), newly available for CT-fluoroscopy (CTF), on image noise, readers' confidence and effective dose compared to filtered back projection (FBP). METHODS: Data from 165 patients (FBP/IA = 82/74) with CTF in the thorax, abdomen and pelvis were included. Noise was analysed in a large-diameter vessel. The impact of reconstruction and variables (e.g. X-ray tube current I) influencing noise and effective dose were analysed by ANOVA and a pairwise t-test with Bonferroni-Holm correction. Noise and readers' confidence were evaluated by three readers. RESULTS: Noise was significantly influenced by reconstruction, I, body region and circumference (all p ≤ 0.0002). IA reduced the noise significantly compared to FBP (p = 0.02). The effect varied for body regions and circumferences (p ≤ 0.001). The effective dose was influenced by the reconstruction, body region, interventional procedure and I (all p ≤ 0.02). The inter-rater reliability for noise and readers' confidence was good (W ≥ 0.75, p < 0.0001). Noise and readers' confidence were significantly better in AIDR-3D compared to FBP (p ≤ 0.03). Generally, IA yielded a significant reduction of the median effective dose. CONCLUSION: The CTF reconstruction by IA showed a significant reduction in noise and effective dose while readers' confidence increased. KEY POINTS: • CTF is performed for image guidance in interventional radiology. • Patient exposure was estimated from DLP documented by the CT. • Iterative CT reconstruction is appropriate to reduce image noise in CTF. • Using iterative CT reconstruction, the effective dose was significantly reduced in abdominal interventions.


Subject(s)
Fluoroscopy/methods , Tomography, X-Ray Computed/methods , Abdomen/diagnostic imaging , Adult , Aged , Aged, 80 and over , Algorithms , Female , Humans , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Male , Middle Aged , Observer Variation , Pelvis/diagnostic imaging , Quality Improvement , Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted/methods , Radiography, Interventional/methods , Reproducibility of Results , Thorax/diagnostic imaging
7.
Skeletal Radiol ; 46(1): 51-58, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27771753

ABSTRACT

OBJECTIVE: To assess the technical success and duration of magnetic resonance imaging (MRI)-guided freehand direct shoulder arthrography (FDSA) with near real-time imaging implemented in a routine shoulder MRI examination on an open 1.0-T MRI scanner, and to assess the learning curve of residents new to this technique. METHODS: An experienced MRI interventionalist (the expert) performed 125 MRI-guided FDSA procedures, and 75 patients were treated by one of three residents without previous experience in MRI-guided FDSA. Technical success rate and duration of MRI-guided FDSA of the expert and the residents were compared. The residents' learning curves were assessed. The occurrence of extra-articular deposition and leakage of contrast media from the puncture site and the subsequent impairment of image interpretation were retrospectively analyzed. RESULTS: Overall technical success was 97.5 %. The expert needed overall fewer puncture needle readjustments and was faster at puncture needle positioning (p < 0.01). The learning curve of the residents, however, was steep. They leveled with the performance of the expert after ≈ 15 interventions. With a minimal amount of training all steps of MRI-guided FDSA can be performed in ≤10 min. CONCLUSION: Magnetic resonance-guided FDSA in an open 1.0-T MRI scanner can be performed with high technical success in a reasonably short amount of time. Only a short learning curve is necessary to achieve expert level.


Subject(s)
Education, Medical, Graduate , Magnetic Resonance Imaging, Interventional/methods , Orthopedics/education , Radiology/education , Shoulder Injuries/diagnostic imaging , Shoulder Joint/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Internship and Residency , Learning Curve , Male , Middle Aged , Retrospective Studies
8.
Pol J Radiol ; 82: 498-505, 2017.
Article in English | MEDLINE | ID: mdl-29662579

ABSTRACT

BACKGROUND: Cardiac magnetic resonance imaging (cMRI) has become the non-invasive reference standard for the evaluation of cardiac function and viability. The introduction of open, high-field, 1.0T (HFO) MR scanners offers advantages for examinations of obese, claustrophobic and paediatric patients.The aim of our study was to compare standard cMRI sequences from an HFO scanner and those from a cylindrical, 1.5T MR system. MATERIAL/METHOD: Fifteen volunteers underwent cMRI both in an open HFO and in a cylindrical MR system. The protocol consisted of cine and unenhanced tissue sequences. The signal-to-noise ratio (SNR) for each sequence and blood-myocardium contrast for the cine sequences were assessed. Image quality and artefacts were rated. The location and number of non-diagnostic segments was determined. Volunteers' tolerance to examinations in both scanners was investigated. RESULTS: SNR was significantly lower in the HFO scanner (all p<0.001). However, the contrast of the cine sequence was significantly higher in the HFO platform compared to the 1.5T MR scanner (0.685±0.41 vs. 0.611±0.54; p<0.001). Image quality was comparable for all sequences (all p>0.05). Overall, only few non-diagnostic myocardial segments were recorded: 6/960 (0.6%) by the HFO and 17/960 (1.8%) segments by the cylindrical system. The volunteers expressed a preference for the open MR system (p<0.01). CONCLUSIONS: Standard cardiac MRI sequences in an HFO platform offer a high image quality that is comparable to the quality of images acquired in a cylindrical 1.5T MR scanner. An open scanner design may potentially improve tolerance of cardiac MRI and therefore allow to examine an even broader patient spectrum.

9.
Comput Methods Programs Biomed ; 240: 107647, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37329803

ABSTRACT

Backgound and Objective: Deep learning-based segmentation of the liver and hepatic lesions therein steadily gains relevance in clinical practice due to the increasing incidence of liver cancer each year. Whereas various network variants with overall promising results in the field of medical image segmentation have been successfully developed over the last years, almost all of them struggle with the challenge of accurately segmenting hepatic lesions in magnetic resonance imaging (MRI). This led to the idea of combining elements of convolutional and transformer-based architectures to overcome the existing limitations. METHODS: This work presents a hybrid network called SWTR-Unet, consisting of a pretrained ResNet, transformer blocks as well as a common Unet-style decoder path. This network was primarily applied to single-modality non-contrast-enhanced liver MRI and additionally to the publicly available computed tomography (CT) data of the liver tumor segmentation (LiTS) challenge to verify the applicability on other modalities. For a broader evaluation, multiple state-of-the-art networks were implemented and applied, ensuring direct comparability. Furthermore, correlation analysis and an ablation study were carried out, to investigate various influencing factors on the segmentation accuracy of the presented method. RESULTS: With Dice similarity scores of averaged 98±2% for liver and 81±28% lesion segmentation on the MRI dataset and 97±2% and 79±25%, respectively on the CT dataset, the proposed SWTR-Unet proved to be a precise approach for liver and hepatic lesion segmentation with state-of-the-art results for MRI and competing accuracy in CT imaging. CONCLUSION: The achieved segmentation accuracy was found to be on par with manually performed expert segmentations as indicated by inter-observer variabilities for liver lesion segmentation. In conclusion, the presented method could save valuable time and resources in clinical practice.


Subject(s)
Liver Neoplasms , Neural Networks, Computer , Humans , Magnetic Resonance Imaging/methods , Tomography, X-Ray Computed/methods , Liver Neoplasms/diagnostic imaging , Image Processing, Computer-Assisted/methods
10.
Front Oncol ; 11: 669437, 2021.
Article in English | MEDLINE | ID: mdl-34336661

ABSTRACT

OBJECTIVE: Liver cancer is one of the most commonly diagnosed cancer, and energy-based tumor ablation is a widely accepted treatment. Automatic and robust segmentation of liver tumors and ablation zones would facilitate the evaluation of treatment success. The purpose of this study was to develop and evaluate an automatic deep learning based method for (1) segmentation of liver and liver tumors in both arterial and portal venous phase for pre-treatment CT, and (2) segmentation of liver and ablation zones in both arterial and portal venous phase for after ablation treatment. MATERIALS AND METHODS: 252 CT images from 63 patients undergoing liver tumor ablation at a large University Hospital were retrospectively included; each patient had pre-treatment and post-treatment multi-phase CT images. 3D voxel-wise manual segmentation of the liver, tumors and ablation region by the radiologist provided reference standard. Deep learning models for liver and lesion segmentation were initially trained on the public Liver Tumor Segmentation Challenge (LiTS) dataset to obtain base models. Then, transfer learning was applied to adapt the base models on the clinical training-set, to obtain tumor and ablation segmentation models both for arterial and portal venous phase images. For modeling, 2D residual-attention Unet (RA-Unet) was employed for liver segmentation and a multi-scale patch-based 3D RA-Unet for tumor and ablation segmentation. RESULTS: On the independent test-set, the proposed method achieved a dice similarity coefficient (DSC) of 0.96 and 0.95 for liver segmentation on arterial and portal venous phase, respectively. For liver tumors, the model on arterial phase achieved detection sensitivity of 71%, DSC of 0.64, and on portal venous phase sensitivity of 82%, DSC of 0.73. For liver tumors >0.5cm3 performance improved to sensitivity 79%, DSC 0.65 on arterial phase and, sensitivity 86%, DSC 0.72 on portal venous phase. For ablation zone, the model on arterial phase achieved detection sensitivity of 90%, DSC of 0.83, and on portal venous phase sensitivity of 90%, DSC of 0.89. CONCLUSION: The proposed deep learning approach can provide automated segmentation of liver tumors and ablation zones on multi-phase (arterial and portal venous) and multi-time-point (before and after treatment) CT enabling quantitative evaluation of treatment success.

11.
PLoS One ; 16(6): e0252678, 2021.
Article in English | MEDLINE | ID: mdl-34129650

ABSTRACT

OBJECTIVES: To investigate whether virtual monoenergetic images (VMI) and iodine maps derived from spectral detector computed tomography (SDCT) improve early assessment of technique efficacy in patients who underwent microwave ablation (MWA) for hepatocellular carcinoma (HCC) in liver cirrhosis. METHODS: This retrospective study comprised 39 patients with 49 HCC lesions treated with MWA. Biphasic SDCT was performed 7.7±4.0 days after ablation. Conventional images (CI), VMI and IM were reconstructed. Signal- and contrast-to-noise ratio (SNR, CNR) in the ablation zone (AZ), hyperemic rim (HR) and liver parenchyma were calculated using regions-of-interest analysis and compared between CI and VMI between 40-100 keV. Iodine concentration and perfusion ratio of HR and residual tumor (RT) were measured. Two readers evaluated subjective contrast of AZ and HR, technique efficacy (complete vs. incomplete ablation) and diagnostic confidence at determining technique efficacy. RESULTS: Attenuation of liver parenchyma, HR and RT, SNR of liver parenchyma and HR, CNR of AZ and HR were significantly higher in low-keV VMI compared to CI (all p<0.05). Iodine concentration and perfusion ratio differed significantly between HR and RT (all p<0.05; e.g. iodine concentration, 1.6±0.5 vs. 2.7±1.3 mg/ml). VMI50keV improved subjective AZ-to-liver contrast, HR-to-liver contrast, visualization of AZ margin and vessels adjacent to AZ compared to CI (all p<0.05). Diagnostic accuracy for detection of incomplete ablation was slightly higher in VMI50keV compared to CI (0.92 vs. 0.89), while diagnostic confidence was significantly higher in VMI50keV (p<0.05). CONCLUSIONS: Spectral detector computed tomography derived low-keV virtual monoenergetic images and iodine maps provide superior early assessment of technique efficacy of MWA in HCC compared to CI.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Microwaves/therapeutic use , Radiofrequency Ablation/methods , Tomography, X-Ray Computed/methods , Aged , Algorithms , Carcinoma, Hepatocellular/complications , Carcinoma, Hepatocellular/surgery , Female , Humans , Liver/diagnostic imaging , Liver/pathology , Liver/surgery , Liver Cirrhosis/complications , Liver Neoplasms/complications , Liver Neoplasms/surgery , Male , Middle Aged , Radiographic Image Interpretation, Computer-Assisted/methods , Retrospective Studies , Signal-To-Noise Ratio
12.
Eur Radiol ; 20(8): 1985-93, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20306080

ABSTRACT

OBJECTIVE: To determine the feasibility and safety of image-guided brachytherapy employing a modified open high-field MR system. METHODS: This is a follow-up study of a development project enabling technologies for interventional use of 1.0T open MRI. Modifications included coils and in-bore visualization, fluoroscopic sequences and user interfaces. We recruited 104 patients with 224 liver malignancies to receive MR-guided brachytherapy. Interventions were performed >20 min after Gd-EOB-DTPA. We recorded interventional parameters including the intervention time (from acquisition of the first scout until the final sequence for brachytherapy treatment planning). Two reviewers assessed MR-fluoroscopic images in comparison to plain CT as used in CT intervention, applying a rating scale of 1-10. Statistical analysis included Friedman and Kendall's W tests. RESULTS: We employed freehand puncture with interactive dynamic imaging for navigation. Technical success rate was 218 complete ablations in 224 tumours (97%). The median intervention time was 61 min. We recorded no adverse events related to the use of MRI. No major complications occurred. The rate of minor complications was 4%. Local control at 3 months was 96%. Superiority of MR-fluoroscopic, Gd-EOB-DTPA-enhanced images over plain CT was highly significant (P < 0.001). CONCLUSION: MR-guided brachytherapy employing open high-field MRI is feasible and safe.


Subject(s)
Brachytherapy/methods , Liver Neoplasms/pathology , Liver Neoplasms/radiotherapy , Magnetic Resonance Imaging/methods , Radiotherapy, Computer-Assisted/methods , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Treatment Outcome
13.
Eur Radiol ; 20(11): 2699-706, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20563725

ABSTRACT

OBJECTIVE: To prospectively evaluate diffusion-weighted imaging (DWI) for early prediction of tumour response in patients with colorectal liver metastases following selective internal radiotherapy (SIRT). METHODS: We evaluated 41 metastases in 21 patients, age 62.9 ± 9.9 years. All patients underwent magnetic resonance imaging (MRI) including breath-hold echoplanar DWI sequences. Imaging was performed before therapy (baseline MRI), 2 days after SIRT (early MRI) as well as 6 weeks later (follow-up MRI). Tumour volume (TV) and intratumoural apparent diffusion coefficient (ADC) were measured independently by two radiologists at all time points. RESULTS: Metastases were categorised as responding lesions (RL; n = 33) or non-responding lesions (NRL; n = 8) according to changes in TV after 6 weeks. We found an inverse correlation of changes in TV and ADC at follow-up MRI with a Pearson's correlation coefficient of r = -0.66 (p < 0.0001). On early MRI, no significant changes in TV were found for either RL or NRL. Conversely, ADC decreased significantly in RL by 10.7 ± 8.4% (p < 0.0001). ADC increased in NRL by 9.6 ± 20.8%, which was not statistically significant (p = 0.40). CONCLUSION: DWI was capable of predicting therapy effects of SIRT in patients with colorectal hepatic metastases as early as 2 days following treatment.


Subject(s)
Brachytherapy , Colorectal Neoplasms/pathology , Diffusion Magnetic Resonance Imaging , Liver Neoplasms/diagnosis , Liver Neoplasms/secondary , Yttrium Radioisotopes/therapeutic use , Adult , Aged , Combined Modality Therapy , Female , Hepatectomy , Humans , Liver Neoplasms/radiotherapy , Male , Middle Aged
14.
PLoS One ; 15(3): e0230024, 2020.
Article in English | MEDLINE | ID: mdl-32196535

ABSTRACT

OBJECTIVE: The objective of this study is to evaluate if intensified pre-scan patient preparation (IPPP) that comprises custom-made educational material on dynamic phase imaging and supervised pre-imaging breath-hold training in addition to standard informative conversation with verbal explanation of breath-hold commands (standard pre-scan patient preparation-SPPP) might reduce the incidence of gadoxetate disodium (Gd-EOB-DTPA)-related transient severe respiratory motion (TSM) and severity of respiratory motion (RM) during dynamic phase liver MRI. MATERIAL AND METHODS: In this bi-institutional study 100 and 110 patients who received Gd-EOB-DTPA for dynamic phase liver MRI were allocated to either IPPP or SPPP at site A and B. The control group comprised 202 patients who received gadoterate meglumine (Gd-DOTA) of which each 101 patients were allocated to IPPP or SPPP at site B. RM artefacts were scored retrospectively in dynamic phase images (1: none- 5: extensive) by five and two blinded readers at site A and B, respectively, and in the hepatobiliary phase of the Gd-EOB-DTPA-enhanced scans by two blinded readers at either site. RESULTS: The incidence of TSM was 15% at site A and 22.7% at site B (p = 0.157). IPPP did not reduce the incidence of TSM in comparison to SPPP: 16.7% vs. 21.6% (p = 0.366). This finding was consistent at site A: 12% vs. 18% (p = 0.401) and site B: 20.6% vs. 25% (p = 0.590). The TSM incidence in patients with IPPP and SPPP did not differ significantly between both sites (p = 0.227; p = 0.390). IPPP did not significantly mitigate RM in comparison to SPPP in any of the Gd-EOB-DTPA-enhanced dynamic phases and the hepatobiliary phase in patients without TSM (all p≥0.072). In the Gd-DOTA control group on the other hand, IPPP significantly mitigated RM in all dynamic phases in comparison to SPPP (all p≤0.031). CONCLUSIONS: We conclude that Gd-EOB-DTPA-related TSM cannot be mitigated by education and training and that Gd-EOB-DTPA-related breath-hold difficulty does not only affect the subgroup of patients with TSM or exclusively the arterial phase as previously proposed.


Subject(s)
Artifacts , Gadolinium DTPA , Heterocyclic Compounds , Liver/diagnostic imaging , Magnetic Resonance Imaging/methods , Movement , Organometallic Compounds , Respiration , Aged , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged
15.
Rofo ; 192(7): 641-656, 2020 Jul.
Article in English, German | MEDLINE | ID: mdl-32615626

ABSTRACT

BACKGROUND: Radiological reports of pancreatic lesions are currently widely formulated as free texts. However, for optimal characterization, staging and operation planning, a wide range of information is required but is sometimes not captured comprehensively. Structured reporting offers the potential for improvement in terms of completeness, reproducibility and clarity of interdisciplinary communication. METHOD: Interdisciplinary consensus finding of structured report templates for solid and cystic pancreatic tumors in computed tomography (CT) and magnetic resonance imaging (MRI) with representatives of the German Society of Radiology (DRG), German Society for General and Visceral Surgery (DGAV), working group Oncological Imaging (ABO) of the German Cancer Society (DKG) and other radiologists, oncologists and surgeons. RESULTS: Among experts in the field of pancreatic imaging, oncology and pancreatic surgery, as well as in a public online survey, structured report templates were developed by consensus. These templates are available on the DRG homepage under www.befundung.drg.de and will be regularly revised to the current state of scientific knowledge by the participating specialist societies and responsible working groups. CONCLUSION: This article presents structured report templates for solid and cystic pancreatic tumors to improve clinical staging (cTNM, ycTNM) in everyday radiology. KEY POINTS: · Structured report templates offer the potential of optimized radiological reporting with regard to completeness, reproducibility and differential diagnosis.. · This article presents consensus-based, structured reports for solid and cystic pancreatic lesions in CT and MRI.. · These structured reports are available open source on the homepage of the German Society of Radiology (DRG) under www.befundung.drg.de.. CITATION FORMAT: · Persigehl T, Baumhauer M, Baeßler B et al. Structured Reporting of Solid and Cystic Pancreatic Lesions in CT and MRI: Consensus-Based Structured Report Templates of the German Society of Radiology (DRG). Fortschr Röntgenstr 2020; 192: 641 - 655.


Subject(s)
Magnetic Resonance Imaging/methods , Pancreatic Cyst/diagnostic imaging , Pancreatic Diseases/diagnostic imaging , Pancreatic Neoplasms/diagnostic imaging , Radiology Information Systems , Research Design , Tomography, X-Ray Computed/methods , Germany , Humans , Radiology , Societies, Medical
16.
Anasthesiol Intensivmed Notfallmed Schmerzther ; 44(10): 670-7; quiz 679, 2009 Oct.
Article in German | MEDLINE | ID: mdl-19834832

ABSTRACT

Image guided minimally invasive local and locoregional tumor ablation techniques like radiofrequency ablation, interstitial brachytherapy, transarterial chemoembolization (TACE) and selective internal radiotherapy (SIRT) with (90)Yttrium ( (90)Y) microspheres have been established as valuable amendments in oncologic therapy concepts. These techniques allow the destruction of extensive liver tumors with an acceptable toxicity profile. Necessity for a safe performance of these procedures is a close collaboration between interventional radiologist and anesthetist.


Subject(s)
Catheter Ablation , Minimally Invasive Surgical Procedures , Neoplasms/surgery , Radiosurgery , Anesthesia , Brachytherapy/adverse effects , Catheter Ablation/adverse effects , Embolization, Therapeutic , Humans , Minimally Invasive Surgical Procedures/adverse effects , Neoplasms/radiotherapy , Radiography, Interventional/adverse effects , Radiosurgery/adverse effects , Vascular Neoplasms/radiotherapy , Vascular Neoplasms/surgery
17.
Eur J Radiol ; 118: 215-222, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31439245

ABSTRACT

PURPOSE: Dual energy CT (DECT) can contribute to the diagnosis of benign and malignant pancreatic lesions. This study examined whether a novel, detector-based spectral CT scanner (SDCT) may improve subjective assessment of different types of pancreatic lesions and if various quantitative maps may improve lesion contrast and differentiation. MATERIALS AND METHODS: 61 consecutive patients who underwent clinical, contrast-agent enhanced, abdominal SDCT scans and showed pancreatic lesions of different origins were included. Subjective image analysis was performed by two readers who assessed image quality, lesion conspicuity and diagnostic confidence on 5-point Likert scales for conventional polyenergetic reconstructions (polyE), virtual monoenergetic images (monoE), virtual non-contrast images, iodine density, iodine overlay, and Z effective (Zeff) maps. Two readers acquired quantitative values from these maps ROI-based from which contrast-to-noise and lesion-to-parenchyma ratios were calculated. RESULTS: MonoE images at low keV levels yielded highest Likert scores regarding lesion conspicuity and reader confidence; iodine overlays facilitated lesion delineation. Inter-observer agreement ranged between substantial and excellent (kappa values 0.73-0.81). Contrast-to-noise-ratios for low keV monoE images were significantly higher, compared to polyE images (e.g. monoE 40 keV p < 0.0001). Marked overlap between PDAC and miscellaneous non-PDAC lesions was present in various spectral reconstructions. CONCLUSIONS: In line with previous studies, monoE images at low keV levels and iodine overlay maps facilitated subjective lesion delineation which was substantiated by the quantitative analysis. Hence, spectral detector CT improves pancreatic lesion conspicuity, while its value for lesion differentiation needs to be further evaluated in larger study cohorts.


Subject(s)
Pancreatic Neoplasms/diagnostic imaging , Tomography, X-Ray Computed/methods , Adult , Aged , Contrast Media , Humans , Iodine , Middle Aged , Observer Variation , Radiographic Image Interpretation, Computer-Assisted/methods , Retrospective Studies , Signal-To-Noise Ratio , Tomography Scanners, X-Ray Computed , Young Adult
18.
Cardiovasc Intervent Radiol ; 42(2): 239-249, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30488303

ABSTRACT

BACKGROUND AND AIMS: The aim of this single-center, open-label phase II study was to assess the efficacy of image-guided high-dose-rate (HDR) brachytherapy (iBT) compared with conventional transarterial embolization (cTACE) in unresectable hepatocellular carcinoma. METHODS: Seventy-seven patients were treated after randomization to iBT or cTACE, as single or repeated interventions. Crossover was allowed if clinically indicated. The primary endpoint was time to untreatable progression (TTUP). Eligibility criteria included a Child-Pugh score of ≤ 8 points, absence of portal vein thrombosis (PVT) at the affected liver lobe, and ≤ 4 lesions. Survival was analyzed by using the Cox proportional hazard model with stratification for Barcelona Clinic Liver Cancer (BCLC) stages. RESULTS: Twenty patients were classified as BCLC-A (iBT/cTACE 8/12), 35 as BCLC-B (16/19), and 22 as BCLC-C (13/9). The 1-, 2-, and 3-year TTUP probabilities for iBT compared with cTACE were 67.5% versus 55.2%, 56.0% versus 27.4%, and 29.5% versus 11.0%, respectively, with an adjusted hazard ratio (HR) of 0.49 (95% confidence interval 0.27-0.89; p = 0.019). The 1-, 2-, and 3-year TTPs for iBT versus cTACE were 56.0% versus 28.2%, 23.9% versus 6.3%, and 15.9% versus 6.3%, respectively, with an adjusted HR of 0.49 (0.29-0.85; p = 0.011). The 1-, 2-, and 3-year OS rates were 78.4% versus 67.7%, 62.0% versus 47.3%, and 36.7% versus 27.0%, respectively, with an adjusted HR of 0.62 (0.33-1.16; p = 0.136). CONCLUSIONS: This explorative phase II trial showed a superior outcome of iBT compared with cTACE in hepatocellular carcinoma and supports proceeding to a phase III trial.


Subject(s)
Brachytherapy/methods , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Radiography, Interventional/methods , Tomography, X-Ray Computed/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Liver/diagnostic imaging , Male , Middle Aged , Proportional Hazards Models , Treatment Outcome
19.
Cardiovasc Intervent Radiol ; 40(6): 884-893, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28160096

ABSTRACT

OBJECTIVE: To assess the feasibility of a hybrid approach employing MRI-guided bile duct (BD) puncture for subsequent fluoroscopy-guided biliary interventions in patients with non-dilated (≤3 mm) or dilated BD (≥3 mm) but unfavorable conditions for ultrasonography (US)-guided BD puncture. METHODS: A total of 23 hybrid interventions were performed in 21 patients. Visualization of BD and puncture needles (PN) in the interventional MR images was rated on a 5-point Likert scale by two radiologists. Technical success, planning time, BD puncture time and positioning adjustments of the PN as well as technical success of the biliary intervention and complication rate were recorded. RESULTS: Visualization even of third-order non-dilated BD and PN was rated excellent by both radiologists with good to excellent interrater agreement. MRI-guided BD puncture was successful in all cases. Planning and BD puncture times were 1:36 ± 2.13 (0:16-11:07) min. and 3:58 ± 2:35 (1:11-9:32) min. Positioning adjustments of the PN was necessary in two patients. Repeated capsular puncture was not necessary in any case. All biliary interventions were completed successfully without major complications. CONCLUSION: A hybrid approach which employs MRI-guided BD puncture for subsequent fluoroscopy-guided biliary intervention is feasible in clinical routine and yields high technical success in patients with non-dilated BD and/or unfavorable conditions for US-guided puncture. Excellent visualization of BD and PN in near-real-time interventional MRI allows successful cannulation of the BD.


Subject(s)
Bile Ducts/diagnostic imaging , Cholestasis/therapy , Drainage/methods , Magnetic Resonance Imaging, Interventional/methods , Punctures/methods , Aged , Aged, 80 and over , Catheterization , Cholestasis/diagnostic imaging , Feasibility Studies , Female , Humans , Male , Middle Aged
20.
Dtsch Med Wochenschr ; 142(5): 341-345, 2017 Mar.
Article in German | MEDLINE | ID: mdl-28282682

ABSTRACT

History and admission findings A 46-year-old woman was admitted because of recurrent postprandial vomiting including weight loss of 30 kg within the last 5 - 6 months. The physical investigation was indicative of preileus. Investigations CT scan revealed an unclear thickening of the jejunum. Treatment and course Explorative laparotomy was performed because of the considerable degree of suffering and a tendency of worsening. Intraoperatively, the preoperatively observed thickening was confirmed at 3 subsequent segments of the jejunum (3 cm long each) prompting to segmental resection of the jejunum. The postoperative course was uneventful. Histopathology revealed submucous, partially transmural, segmental edema compatible with an angioneurotic edema. Amyloidosis, sprue and malignancy could be excluded. A C1 esterase inhibitor test war normal. A further search for possible causes revealed ACE inhibitor medication for hypertension. Conclusion The differential diagnostic assessment of isolated small intestine diseases must take into account rare systemic disease. The knowledge of the history of medicine can be useful to detect the - not mandatory - connection to angioedema.


Subject(s)
Abdominal Pain/chemically induced , Abdominal Pain/diagnosis , Angioedema/chemically induced , Angioedema/diagnosis , Angiotensin-Converting Enzyme Inhibitors/adverse effects , Jejunal Diseases/chemically induced , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Diagnosis, Differential , Female , Humans , Hypertension/complications , Hypertension/drug therapy , Jejunal Diseases/diagnosis , Middle Aged , Recurrence
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