Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Keywords: RADIOFREQUENCY ABLATION ; TISSUE ABLATION
    Abstract: BACKGROUND: Size and shape of the treatment zone after Irreversible electroporation (IRE) can be difficult to depict due to the use of multiple applicators with complex spatial configuration. Exact geometrical definition of the treatment zone, however, is mandatory for acute treatment control since incomplete tumor coverage results in limited oncological outcome. In this study, the "Chebyshev Center Concept" was introduced for CT 3d rendering to assess size and position of the maximum treatable tumor at a specific safety margin. METHODS: In seven pig livers, three different IRE protocols were applied to create treatment zones of different size and shape: Protocol 1 (n = 5 IREs), Protocol 2 (n = 5 IREs), and Protocol 3 (n = 5 IREs). Contrast-enhanced CT was used to assess the treatment zones. Technique A consisted of a semi-automated software prototype for CT 3d rendering with the "Chebyshev Center Concept" implemented (the "Chebyshev Center" is the center of the largest inscribed sphere within the treatment zone) with automated definition of parameters for size, shape and position. Technique B consisted of standard CT 3d analysis with manual definition of the same parameters but position. RESULTS: For Protocol 1 and 2, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were not significantly different between Technique A and B. For Protocol 3, short diameter of the treatment zone and diameter of the largest inscribed sphere within the treatment zone were significantly smaller for Technique A compared with Technique B (41.1 +/- 13.1 mm versus 53.8 +/- 1.1 mm and 39.0 +/- 8.4 mm versus 53.8 +/- 1.1 mm; p 〈 0.05 and p 〈 0.01). For Protocol 1, 2 and 3, sphericity of the treatment zone was significantly larger for Technique A compared with B. CONCLUSIONS: Regarding size and shape of the treatment zone after IRE, CT 3d rendering with the "Chebyshev Center Concept" implemented provides significantly different results compared with standard CT 3d analysis. Since the latter overestimates the size of the treatment zone, the "Chebyshev Center Concept" could be used for a more objective acute treatment control.
    Type of Publication: Journal article published
    PubMed ID: 24410997
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Keywords: SURVIVAL ; DIAGNOSIS ; tomography ; MULTIPLE-MYELOMA ; ENHANCEMENT ; CLINICAL STAGING SYSTEM ; BONE-MARROW INFILTRATION ; MYELOMA WORKING GROUP ; CONVENTIONAL RADIOGRAPHY
    Abstract: PURPOSE: To compare sensitivity of whole-body Computed Tomography (wb-CT) and whole-body Magnetic Resonance Imaging (wb-MRI) with Projection Radiography (PR) regarding each method's ability to detect osteolyses in patients with monoclonal plasma cell disease. PATIENTS AND METHODS: The bone status of 171 patients was evaluated. All patients presented with multiple myeloma (MM) of all stages, monoclonal gammopathy of unknown significance (MGUS) or solitary plasmacytoma. Two groups were formed. Group A consisted of 52 patients (26 females, 26 males) with an average age of 62 years (range, 45-89 years) who received, both, PR and wb-CT as part of their diagnostic work-up. Group B comprised 119 patients (58 females, 61 males) averaging 57 years of age (range, 20-80 years) who received, both, PR and wb-MRI. Two experienced radiologists were blinded regarding the disease status and assessed the number and location of osteolyses in consensus. A distinction was made between axial and extra-axial lesions. RESULTS: In group A, wb-CT revealed osteolyses in 12 patients (23%) that were not detected in PR. CT was superior in detecting lesions in patients with osteopenia and osteoporosis. Compared with PR, wb-CT was significantly more sensitive in detecting osteolyses than PR (p〈0.001). This was particularly true for axial lesions. Additionally, CT revealed clinically relevant incidental findings in 33 patients (63%). In group B, wb-MRI revealed lesions in 19 patients (16%) that were not detected in PR. All lesions detected by PR were also detected by wb-MRI and wb-CT. Wb-MRI and wb-CT are each superior to PR in detecting axial lesions. CONCLUSION: Wb-CT can detect 23% more focal lesions than PR, especially in the axial skeleton. Therefore, this imaging method should be preferred over PR in the diagnostic work-up and staging of patients with monoclonal plasma cell disease.
    Type of Publication: Journal article published
    PubMed ID: 24793843
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Abstract: PURPOSE: To investigate the value of multiparametric magnetic resonance imaging (mpMRI) and to predict extracapsular extension (ECE), seminal vesicle (SV) infiltration, and a negative surgical margin (SM) status at radical prostatectomy (RP) for different prostate cancer (PC) risk groups. PATIENTS AND METHODS: In the study, 805 men underwent 3 tesla mpMRI without endorectal coil before MRI/transrectal ultrasonography-fusion guided prostate biopsy. MRIs were analyzed using the prostate imaging reporting and data system. The cohort was classified into risk groups according to National Comprehensive Cancer Network (NCCN) criteria. Of 132 men who subsequently underwent RP, pathologic stage and SM status at RP were used as reference. Retrospectively, we investigated a European Society of Urogenital Radiology (ESUR) score for ECE and SV-infiltration. Statistical analyses included regression analyses, receiver operating characteristics (ROC), and Youden Index to assess an ESUR-score cutoff. RESULTS: Area under the curve in ROC curve analyses was 0.82 for ESUR-ECE score to detect pT3a-disease and 0.77 for ESUR-SV score for pT3b. Using a cutoff of 4 for ECE and of 2 for SV, the positive predictive value of the ECE-score for harboring pT3 was 50.0%, 90.0%, and 88.8% for the low-, intermediate- and high-risk cohort. Retrospectively, the use of the ESUR-ECE score preoperatively would have changed the initial surgical plan, according to NCCN criteria, in 31.1% of patients. In the high-risk subgroup, 9/35 (25.7%) patients were correctly assessed as not harboring pT3 by imaging (ECE score 〈4), and would have allowed secure robot-assisted radical prostatectomy and nerve-sparing surgery (NSS). When T3 suspicion on preoperative MRI would be taken into account, intraoperative frozen-sections (IFS) might avoid positive SM in 12/18 high-risk patients and an oncologic secure NSS in 8/20 intermediate-risk patients. CONCLUSION: Prediction of pT3 disease is crucial to plan NSS and to achieve negative SM in RP. Standardized ECE scoring on mpMRI is an independent predictor of pT3 and may help to plan RP with oncologic security, even in high-risk patients. In addition, it allows more accurate selection of a subgroup of patients for systematic and MRI-guided IFS.
    Type of Publication: Journal article published
    PubMed ID: 26154571
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Abstract: On February 26th, 2013 the patient law became effective in Germany. Goal of the lawmakers was a most authoritative case law for liability of malpractice and to improve enforcement of the rights of the patients. The following article contains several examples detailing legal situation. By no means should these discourage those persons who treat patients. Rather should they be sensitized to to various aspects of this increasingly important field of law. To identify relevant sources according to judicial standard research was conducted including first- and second selection. Goal was the identification of jurisdiction, literature and other various analyses that all deal with liability of malpractice and patient law within the field of Interventional Radiology - with particular focus on transarterial chemoembolization of the liver and related procedures. In summary, 89 different sources were included and analyzed. The individual who treats a patient is liable for an error in treatment if it causes injury to life, the body or the patient's health. Independent of the error in treatment the individual providing medical care is liable for mistakes made in the context of obtaining informed consent. Prerequisite is the presence of an error made when obtaining informed consent and its causality for the patient's consent for the treatment. Without an effective consent the treatment is considered illegal whether it was free of treatment error or not. The new patient law does not cause material change of the German liablity of malpractice law. Key points: * On February 26th, 2013 the new patient law came into effect. Materially, there was no fundamental remodeling of the German liability for medical malpractice.* Regarding a physician's liability for medical malpractice two different elements of an offence come into consideration: for one the liability for malpractice and, in turn, liability for errors made during medical consultation in the process of obtaining informed consent.* Forensic practice shows that patients frequently enforce both offences concurrently. Citation Format: * Sommer SA, Geissler R, Stampfl U et al. Medical Liability and Patient Law in Germany: Main Features with Particular Focus on Treatments in the Field of Interventional Radiology. Fortschr Rontgenstr 2016; 188: 353 - 358.
    Type of Publication: Journal article published
    PubMed ID: 26716403
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    Abstract: PURPOSE: To characterize parametric changes measured by sequential dynamic contrast enhanced perfusion MRI (DCE-MRI) during primary proton and carbon ion irradiation of prostate cancer using a novel hypofractionated raster scan technique to determine the potential of pharmacokinetic analysis for monitoring treatment effects of this novel irradiation scheme. MATERIALS AND METHODS: Ninety-two patients were evaluated prospectively with DCE-MRI at baseline, day 10 during therapy, and 6weeks, 6months and 18months after treatment completion. After motion correction and co-registration to morphological T2-weighted images, tumors and normal appearing contralateral parenchyma (NACP) were segmented manually on T2W images and ROI statistics calculated for pharmacokinetic parameters K(trans), kep and ve using the standard Tofts model. RESULTS: The volume transfer constant (K(trans), p〈0.001/p=0.010) and the leakage space partial volume (ve, p〈0.001/p=0.005) showed a statistically significant increase during therapy with protons and carbon ions, respectively. Parametric increases occurred only in patients naive to antihormonal therapy (AHT), and were maximal 10days after the begining of treatment. The rate constant (kep) showed a significant increase only for proton, but not for carbon irradiation (p=0.021). Statistically significant differences between PC and NACP were observed for all parameters (p〈0.001). AHT naive patients with persistent PSA elevation above 1ng/ml at 12months experienced statistically significant elevation of K(trans) and ve compared to those with PSA suppression (p=0.04/p=0.023). CONCLUSION: DCE parametric changes following ion particle irradiation of the prostate have not been previously reported. Their development into potential non-invasive imaging biomarkers for assessment of treatment response and efficacy is expected to be aided by the data on the magnitude and temporal evolution of parametric responses of cancer and normal tissue during and after therapy presented here, especially the changes of K(trans) and ve during therapy and their different measurement levels within tumors and in normal appearing contralateral tissue.
    Type of Publication: Journal article published
    PubMed ID: 27237059
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    Abstract: BACKGROUND: Multiparametric magnetic resonance imaging (mpMRI) and MRI fusion targeted biopsy (FTB) detect significant prostate cancer (sPCa) more accurately than conventional biopsies alone. OBJECTIVE: To evaluate the detection accuracy of mpMRI and FTB on radical prostatectomy (RP) specimen. DESIGN, SETTING AND PARTICIPANTS: From a cohort of 755 men who underwent transperineal MRI and transrectal ultrasound fusion biopsy under general anesthesia between 2012 and 2014, we retrospectively analyzed 120 consecutive patients who had subsequent RP. All received saturation biopsy (SB) in addition to FTB of lesions with Prostate Imaging Reporting and Data System (PI-RADS) score 〉/=2. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The index lesion was defined as the lesion with extraprostatic extension, the highest Gleason score (GS), or the largest tumor volume (TV) if GS were the same, in order of priority. GS 3+3 and TV 〉/=1.3ml or GS 〉/=3+4 and TV 〉/=0.55ml were considered sPCa. We assessed the detection accuracy by mpMRI and different biopsy approaches and analyzed lesion agreement between mpMRI and RP specimen. RESULTS AND LIMITATIONS: Overall, 120 index and 71 nonindex lesions were detected. Overall, 107 (89%) index and 51 (72%) nonindex lesions harbored sPCa. MpMRI detected 110 of 120 (92%) index lesions, FTB (two cores per lesion) alone diagnosed 96 of 120 (80%) index lesions, and SB alone diagnosed 110 of 120 (92%) index lesions. Combined SB and FTB detected 115 of 120 (96%) index foci. FTB performed significantly less accurately compared with mpMRI (p=0.02) and the combination for index lesion detection (p=0.002). Combined FTB and SB detected 97% of all sPCa lesions and was superior to mpMRI (85%), FTB (79%), and SB (88%) alone (p〈0.001 each). Spearman's rank correlation coefficient for index lesion agreement between mpMRI and RP was 0.87 (p〈0.001). Limitations included the retrospective design, multiple operators, and nonblinding of radiologists. CONCLUSIONS: MpMRI identified 92% of index lesions compared with RP histopathology. The combination of FTB and SB was superior to both approaches alone, reliably detecting 97% of sPCa lesions. PATIENT SUMMARY: Multiparametric magnetic resonance imaging detects the index lesion accurately in 9 of 10 patients; however, the combined biopsy approach, while missing less significant cancer, comes at the cost of detecting more insignificant cancer.
    Type of Publication: Journal article published
    PubMed ID: 26810346
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    Keywords: POPULATION ; AGE ; RELIABILITY ; HEAD ; ADULTS ; HEALTHY-SUBJECTS ; NORMATIVE VALUES ; ELBOW POSITION ; HAND ; DYNAMOMETER
    Abstract: PURPOSE: The objective of this study was to examine the influence of anthropometric data, occupational manual strain, DASH (disability of arm, shoulder and hand) score and range of motion (ROM) on grip strength and key pinch. An additional goal was to develop models that enable the prediction of hand strength using the aforementioned parameters. METHODS: Normative data generated from a healthy working population (n = 750) served as basis for the statistical analysis. Prediction models for hand strength were developed using multivariate regression analysis. RESULTS: Gender, body weight and height, BMI and extension ROM correlate positively, age and DASH score, however, correlate negatively with grip strength and key pinch. Occupational manual strain has no influence on hand strength. The predictive power of the developed models was 68.4 % for grip strength and 57.1 % for key pinch. CONCLUSIONS: The developed models enable the prediction of hand strength using easily obtainable data points. The models will have application in clinical practice, physiological studies, medical evidence and rehab decisions.
    Type of Publication: Journal article published
    PubMed ID: 22983146
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    Keywords: MANAGEMENT ; WRIST ARTHROSCOPY ; OSTEOTOMY
    Abstract: PURPOSE: To compare short- and midterm functional and subjective outcomes of arthroscopically repaired Palmer 1B tears. METHODS: At 2 time points, we evaluated 49 patients with Palmer 1B tears who underwent arthroscopic repair. We examined 46 patients (23 males and 23 females) in the short-term at an average of 11 months (range, 6-23 mo) postoperatively. In a second midterm follow-up, we examined 40 patients (20 males and 20 females) an average of 4.8 years (range, 4.2-5.9 y) after repair. Between short- and midterm follow-ups, 6 patients underwent an ulnar-shortening osteotomy to alleviate persistent ulnar-sided symptoms. Objective and subjective evaluation included the determination of range of motion, grip strength, pain, and wrist scores (modified Mayo wrist score and Disabilities of Arm, Shoulder, and Hand score). RESULTS: Compared with short-term repair results, midterm outcomes showed a further improvement in pain, wrist scores, grip strength, and motion. Neither static nor dynamic ulnar variance was correlated to preoperative and postoperative Disabilities of the Arm, Shoulder, and Hand scores, short-term modified Mayo wrist scores, or need for ulnar-shortening osteotomy. Five patients improved only after having received an ulnar shortening osteotomy. CONCLUSIONS: After repair of Palmer 1B lesions, patients continued to improve in function and comfort at least into the second year, although some needed to have the ulna shortened to achieve this result. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.
    Type of Publication: Journal article published
    PubMed ID: 23101530
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    Abstract: PURPOSE: The purpose of this study was to compare safety and feasibility of proton therapy with that of carbon ion therapy in hypofractionated raster-scanned irradiation of the prostate, in a prospective randomized phase 2 trial. METHODS AND MATERIALS: In this trial, 92 patients with localized prostate cancer were enrolled. Patients were randomized to receive either proton therapy (arm A) or carbon ion therapy (arm B) and treated with a total dose of 66 Gy(relative biological effectiveness [RBE]) administered in 20 fractions (single dose of 3.3 Gy[RBE]). Patients were stratified by the use of antihormone therapy. Primary endpoint was the combined assessment of safety and feasibility. Secondary endpoints were specific toxicities, prostate-specific antigen progression-free survival (PFS), overall survival (OS), and quality of life (QoL). RESULTS: Ninety-one patients completed therapy and have had a median follow-up of 22.3 months. Among acute genitourinary toxicities, grade 1 cystitis rates were 34.1% (39.1% in A; 28.9% in B) and 17.6% grade 2 (21.7% in A; 13.3% in B). Seven patients (8%) required urinary catheterization during treatment due to urinary retention, 5 of whom were in arm A. Regarding acute gastrointestinal toxicities, 2 patients treated with protons developed grade 3 rectal fistulas. Grade 1 radiation proctitis occurred in 12.1% (13.0% in A; 11.1% in B) and grade 2 in 5.5% (8.7% in A; 2.2% in B). No statistically significant differences in toxicity profiles between arms were found. Reduced QoL was evident mainly in fatigue, pain, and urinary symptoms during therapy and 6 weeks thereafter. All European Organization for Research and Treatment of Cancer QLQ-C30 and -PR25 scores improved during follow-up. CONCLUSIONS: Hypofractionated irradiation using either carbon ions or protons results in comparable acute toxicities and QoL parameters. We found that hypofractionated particle irradiation is feasible and may be safe. Due to the occurrence of gel in the rectal wall and the consecutive occurrence of 2 rectal fistulas, we stopped using the insertion of spacer gel. Longer follow-up is necessary for evaluation of PFS and OS. (Ion Prostate Irradiation (IPI); NCT01641185; ClinicalTrials.gov.).
    Type of Publication: Journal article published
    PubMed ID: 27084659
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    Abstract: OBJECTIVE: To evaluate the diagnostic performance of an automated analysis tool for the assessment of prostate cancer based on multiparametric magnetic resonance imaging (mpMRI) of the prostate. METHODS: A fully automated analysis tool was used for a retrospective analysis of mpMRI sets (T2-weighted, T1-weighted dynamic contrast-enhanced, and diffusion-weighted sequences). The software provided a malignancy prediction value for each image pixel, defined as Malignancy Attention Index (MAI) that can be depicted as a colour map overlay on the original images. The malignancy maps were compared to histopathology derived from a combination of MRI-targeted and systematic transperineal MRI/TRUS-fusion biopsies. RESULTS: In total, mpMRI data of 45 patients were evaluated. With a sensitivity of 85.7% (with 95% CI of 65.4-95.0), a specificity of 87.5% (with 95% CI of 69.0-95.7) and a diagnostic accuracy of 86.7% (with 95% CI of 73.8-93.8) for detection of prostate cancer, the automated analysis results corresponded well with the reported diagnostic accuracies by human readers based on the PI-RADS system in the current literature. CONCLUSION: The study revealed comparable diagnostic accuracies for the detection of prostate cancer of a user-independent MAI-based automated analysis tool and PI-RADS-scoring-based human reader analysis of mpMRI. Thus, the analysis tool could serve as a detection support system for less experienced readers. The results of the study also suggest the potential of MAI-based analysis for advanced lesion assessments, such as cancer extent and staging prediction.
    Type of Publication: Journal article published
    PubMed ID: 27454770
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...