Diane M Renz

Humboldt-Universität zu Berlin, Berlín, Berlin, Germany

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Publications (65)133.11 Total impact

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    ABSTRACT: Digital X-ray radiogrammetry (DXR) is a computer-assisted technique used to quantify cortical bone density of the metacarpals. The influence of metacarpal bone rotation and type of cast material on bone mineral density (BMD) measurements using the DXR technique was tested.
    International Journal of Computer Assisted Radiology and Surgery 07/2014; · 1.36 Impact Factor
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    ABSTRACT: The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) with mammography (MG) and combined CESM + MG in terms of detection and size estimation of histologically proven breast cancers in order to assess the potential to reduce radiation exposure. A total of 118 patients underwent MG and CESM and had final histological results. CESM was performed as a bilateral examination starting 2 min after injection of iodinated contrast medium. Three independent blinded radiologists read the CESM, MG, and CESM + MG images with an interval of at least 4 weeks to avoid case memorization. Sensitivity and size measurement correlation and differences were calculated, average glandular dose (AGD) levels were compared, and breast densities were reported. Fisher's exact and Wilcoxon tests were performed. A total of 107 imaging pairs were available for analysis. Densities were ACR1: 2, ACR2: 45, ACR3: 42, and ACR4: 18. Mean AGD was 1.89 mGy for CESM alone, 1.78 mGy for MG, and 3.67 mGy for the combination. In very dense breasts, AGD of CESM was significantly lower than MG. Sensitivity across readers was 77.9 % for MG alone, 94.7 % for CESM, and 95 % for CESM + MG. Average tumor size measurement error compared to postsurgical pathology was -0.6 mm for MG, +0.6 mm for CESM, and +4.5 mm for CESM + MG (p < 0.001 for CESM + MG vs. both modalities). CESM alone has the same sensitivity and better size assessment as CESM + MG and was significantly better than MG with only 6.2 % increase in AGD. The combination of CESM + MG led to systematic size overestimation. When a CESM examination is planned, additional MG can be avoided, with the possibility of saving up to 61 % of radiation dose, especially in patients with dense breasts.
    Breast Cancer Research and Treatment 07/2014; · 4.47 Impact Factor
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    ABSTRACT: In contrast to conventional breast imaging techniques, one major diagnostic benefit of breast magnetic resonance imaging (MRI) is the simultaneous acquisition of morphologic and dynamic enhancement characteristics, which are based on angiogenesis and therefore provide insights into tumor pathophysiology. The aim of this investigation was to intraindividually compare 2 macrocyclic MRI contrast agents, with low risk for nephrogenic systemic fibrosis, in the morphologic and dynamic characterization of histologically verified mass breast lesions, analyzed by blinded human evaluation and a fully automatic computer-assisted diagnosis (CAD) technique. Institutional review board approval and patient informed consent were obtained. In this prospective, single-center study, 45 women with 51 histopathologically verified (41 malignant, 10 benign) mass lesions underwent 2 identical examinations at 1.5 T (mean time interval, 2.1 days) with 0.1-mmol kg doses of gadoteric acid and gadobutrol. All magnetic resonance images were visually evaluated by 2 experienced, blinded breast radiologists in consensus and by an automatic CAD system, whereas the morphologic and dynamic characterization as well as the final human classification of lesions were performed based on the categories of the Breast imaging reporting and data system MRI atlas. Lesions were also classified by defining their probability of malignancy (morpho-dynamic index; 0%-100%) by the CAD system. Imaging results were correlated with histopathology as gold standard. The CAD system coded 49 of 51 lesions with gadoteric acid and gadobutrol (detection rate, 96.1%); initial signal increase was significantly higher for gadobutrol than for gadoteric acid for all and the malignant coded lesions (P < 0.05). Gadoteric acid resulted in more postinitial washout curves and fewer continuous increases of all and the malignant lesions compared with gadobutrol (CAD hot spot regions, P < 0.05). Morphologically, the margins of the malignancies were different between the 2 agents, whereas gadobutrol demonstrated more spiculated and fewer smooth margins (P < 0.05). Lesion classifications by the human observers and by the morpho-dynamic index compared with the histopathologic results did not significantly differ between gadoteric acid and gadobutrol. Macrocyclic contrast media can be reliably used for breast dynamic contrast-enhanced MRI. However, gadoteric acid and gadobutrol differed in some dynamic and morphologic characterization of histologically verified breast lesions in an intraindividual, comparison. Besides the standardization of technical parameters and imaging evaluation of breast MRI, the standardization of the applied contrast medium seems to be important to receive best comparable MRI interpretation.
    Investigative radiology 03/2014; · 4.85 Impact Factor
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    ABSTRACT: To evaluate postinterventional magnetic resonance imaging (MRI) characteristics following MRI-guided laser ablation of osteoid osteoma (OO). 35 patients treated with MRI-guided laser ablation underwent follow-up MRI immediately after the procedure, after 3, 6, 12, 24, 36, and up to 48 months. The imaging protocol included multiplanar fat-saturated T2w TSE, unenhanced and contrast-enhanced T1w SE, and subtraction images. MR images were reviewed regarding the appearance and size of treated areas, and presence of periablation bone and soft tissue changes. Imaging was correlated with clinical status. Mean follow-up time was 13.6 months. 28/35 patients (80%) showed a postinterventional "target-sign" appearance consisting of a fibrovascular rim zone and a necrotic core area. After an initial increase in total lesion diameter after 3 months, a subsequent progressive inward remodeling process of the zonal compartments was observed for up to 24 months. Periablation bone and soft tissue changes showed a constant decrease over time. MR findings correlated well with the clinical status. Clinical success was achieved in 32/35 (91%). Evaluation of long-term follow-up MRI after laser ablation of OO identified typical postinterventional changes and thus may contribute to the interpretation of therapeutic success and residual or recurrent OO in suspected cases.
    European journal of radiology 01/2014; · 2.65 Impact Factor
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    ABSTRACT: Background. The aim of this study was to evaluate imaging-based response to standardized neoadjuvant chemotherapy (NACT) regimen by dynamic contrast-enhanced magnetic resonance mammography (DCE-MRM), whereas MR images were analyzed by an automatic computer-assisted diagnosis (CAD) system in comparison to visual evaluation. MRI findings were correlated with histopathologic response to NACT and also with the occurrence of metastases in a follow-up analysis. Patients and methods. Fifty-four patients with invasive ductal breast carcinomas received two identical MRI examinations (before and after NACT; 1.5T, contrast medium gadoteric acid). Pre-therapeutic images were compared with post-therapeutic examinations by CAD and two blinded human observers, considering morphologic and dynamic MRI parameters as well as tumor size measurements. Imaging-assessed response to NACT was compared with histopathologically verified response. All clinical, histopathologic, and DCE-MRM parameters were correlated with the occurrence of distant metastases. Results. Initial and post-initial dynamic parameters significantly changed between pre- and post-therapeutic DCE-MRM. Visually evaluated DCE-MRM revealed sensitivity of 85.7%, specificity of 91.7%, and diagnostic accuracy of 87.0% in evaluating the response to NACT compared to histopathology. CAD analysis led to more false-negative findings (37.0%) compared to visual evaluation (11.1%), resulting in sensitivity of 52.4%, specificity of 100.0%, and diagnostic accuracy of 63.0%. The following dynamic MRI parameters showed significant associations to occurring metastases: Post-initial curve type before NACT (entire lesions, calculated by CAD) and post-initial curve type of the most enhancing tumor parts after NACT (calculated by CAD and manually). Conclusions. In the accurate evaluation of response to neoadjuvant treatment, CAD systems can provide useful additional information due to the high specificity; however, they cannot replace visual imaging evaluation. Besides traditional prognostic factors, contrast medium-induced dynamic MRI parameters reveal significant associations to patient outcome, i.e. occurrence of distant metastases.
    Acta oncologica (Stockholm, Sweden) 12/2013; · 2.27 Impact Factor
  • Annals of the rheumatic diseases 11/2013; · 8.11 Impact Factor
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    ABSTRACT: /st>Positioning central venous catheters (CVCs) in the proper part of the superior vena cava (SVC) is difficult. The aim of this exploratory study was to analyse topographic relationships of the extrapericardial SVC using chest X-ray (CXR) and computed tomography (CT). This included an appraisal of rules for optimal CVC tip placement. /st>We retrospectively evaluated 100 patients with CVCs who underwent bedside CXR and CT on the same day. Distances between the sternoclavicular joint (SCJ), tracheal carina, SVC origin, pericardial reflection, and CVC tip were analysed on CT and, if visible, on CXR. These measurements served to locate the extrapericardial SVC in relation to anatomical landmarks. Different strategies for CVC tip positioning were evaluated. /st>The mean (standard deviation) extrapericardial length of the SVC was 26 (12) mm. The average position of the pericardial reflection was 5 mm below the carina (range, 29 mm below to 25 mm above). In our patient population, the best results in terms of tip positions in the extrapericardial SVC would have been achieved by using 85% of the SCJ-to-carina distance (in 86%) or by positioning the CVC tip 9 mm above the carina (in 84% of patients). /st>The extrapericardial part of the SVC varies considerably in length and position, and rules of thumb based on anatomical landmarks should be used cautiously. In our series, using 85% of the SCJ-to-carina distance or placing the CVC tip 9 mm above the carina would have resulted in a high percentage of positions in the extrapericardial SVC.
    BJA British Journal of Anaesthesia 10/2013; · 4.24 Impact Factor
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    ABSTRACT: To compare mammography (MG), contrast-enhanced spectral mammography (CESM), and magnetic resonance imaging (MRI) in the detection and size estimation of histologically proven breast cancers using postoperative histology as the gold standard. After ethical approval, 80 women with newly diagnosed breast cancer underwent MG, CESM, and MRI examinations. CESM was reviewed by an independent experienced radiologist, and the maximum dimension of suspicious lesions was measured. For MG and MRI, routine clinical reports of breast specialists, with judgment based on the BI-RADS lexicon, were used. Results of each imaging technique were correlated to define the index cancer. Fifty-nine cases could be compared to postoperative histology for size estimation. Breast cancer was visible in 66/80 MG, 80/80 CESM, and 77/79 MRI examinations. Average lesion largest dimension was 27.31 mm (SD 22.18) in MG, 31.62 mm (SD 24.41) in CESM, and 27.72 mm (SD 21.51) in MRI versus 32.51 mm (SD 29.03) in postoperative histology. No significant difference was found between lesion size measurement on MRI and CESM compared with histopathology. Our initial results show a better sensitivity of CESM and MRI in breast cancer detection than MG and a good correlation with postoperative histology in size assessment. • Contrast-enhanced spectral mammography (CESM) is slowly being introduced into clinical practice. • Access to breast MRI is limited by availability and lack of reimbursement. • Initial results show a better sensitivity of CESM and MRI than conventional mammography. • CESM showed a good correlation with postoperative histology in size assessment. • Contrast-enhanced spectral mammography offers promise, seemingly providing information comparable to MRI.
    European Radiology 09/2013; · 4.34 Impact Factor
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    ABSTRACT: To evaluate the accuracy, safety, and efficacy of cervical nerve root injection therapy using magnetic resonance guidance in an open 1.0 T MRI system. Between September 2009 and April 2012, a total of 21 patients (9 men, 12 women; mean age 47.1 ± 11.1 years) underwent MR-guided cervical periradicular injection for cervical radicular pain in an open 1.0 T system. An interactive proton density-weighted turbo spin echo (PDw TSE) sequence was used for real-time guidance of the MR-compatible 20-gauge injection needle. Clinical outcome was evaluated on a verbal numeric rating scale (VNRS) before injection therapy (baseline) and at 1 week and 1, 3, and 6 months during follow-up. All procedures were technically successful and there were no major complications. The mean preinterventional VNRS score was 7.42 and exhibited a statistically significant decrease (P < 0.001) at all follow-up time points: 3.86 ± 1.53 at 1 week, 3.21 ± 2.19 at 1 month, 2.58 ± 2.54 at 3 months, and 2.76 ± 2.63 at 6 months. At 6 months, 14.3 % of the patients reported complete resolution of radicular pain and 38.1 % each had either significant (4-8 VNRS score points) or mild (1-3 VNRS score points) relief of pain; 9.5 % experienced no pain relief. Magnetic resonance fluoroscopy-guided periradicular cervical spine injection is an accurate, safe, and efficacious treatment option for patients with cervical radicular pain. The technique may be a promising alternative to fluoroscopy- or CT-guided injections of the cervical spine, especially in young patients and in patients requiring repeat injections.
    CardioVascular and Interventional Radiology 09/2013; · 2.09 Impact Factor
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    ABSTRACT: Purpose: To evaluate the additional benefit of true geometric (air-gap) magnification views for the characterization of microcalcifications in digital mammography.Materials and Methods: After ethical approval, we retrospectively reviewed patient records to identify 100 patients with suspicious microcalcifications (35 malignant, 65 benign) who had a standard digital mammography and an additional digital magnification view in the same projection within three months. All images were obtained using an amorphous silicon-based full-field digital system (Senographe 2000 D, GE Healthcare, Chalfont St. Giles, UK). Images were independently analyzed by six board-certified radiologists. The probability of malignancy was estimated using first standard contact mammography alone (MG) and then mammography in combination with the magnification view (MG+MAG) using a modified Breast Imaging Reporting and Data System (BI-RADS) classification system and a percentage scale. Results were compared using receiver operating characteristic (ROC) analysis. In addition, readers assessed the subjective visibility of the calcifications.Results: For all six readers combined, the area under the curve (AUC) was 0.664 ± 0.052 for MG and 0.813 ± 0.042 for MG + MAG, resulting in a statistically significant improvement of 0.148 ± 0.120. Each reader had a higher AUC for MG + MAG than MG, with the improvement being statistically significant in four of the six readers. In 76.34 % of the cases, MG + MAG resulted in better visibility of calcifications compared with mammography alone. In 33 % slightly more and in 39 % significantly more calcifications were found.Conclusion: Even in digital mammography with the option of using electronic magnification (zoom) at the viewing workstation, true geometric (air-gap) magnification views remain important for the visibility and correct classification of microcalcifications and for the assessment of their extent.Citation Format:
    RöFo - Fortschritte auf dem Gebiet der R 09/2013; · 2.76 Impact Factor
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    ABSTRACT: To compare the diagnostic efficacy of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) vs. multidetector computed tomography (MDCT) for the detection and classification of focal liver lesions, differentiated also for lesion entity and size; a separate analysis of pre- and postcontrast images as well as T2-weighted MRI sequences of focal and exclusively solid lesions was integrated. Twenty-nine patients with 130 focal liver lesions underwent MDCT (64-detector-row; contrast medium iopromide; native, arterial, portalvenous, venous phase) and MRI (1.5-T; dynamic and tissue-specific phase 20min after application of Gd-EOB-DTPA). Hepatic lesions were verified against a standard of reference (SOR). CT and MR images were independently analysed by four blinded radiologists on an ordinal 6-point-scale, determining lesion classification and diagnostic confidence. Among 130 lesions, 68 were classified as malignant and 62 as benign by SOR. The detection of malignant and benign lesions differed significantly between combined and postcontrast MRI vs. MDCT; overall detection rate was 91.5% for combined MRI and 80.4% for combined MDCT (p<0.05). Considering all four readers together, combined MDCT achieved sensitivity of 66.2%, specificity of 79.0%, and diagnostic accuracy of 72.3%; combined MRI reached superior diagnostic efficacy: sensitivity 86.8%, specificity 94.4%, accuracy 90.4% (p<0.05). Differentiated for lesion size, in particular lesions <20mm revealed diagnostic benefit by MRI. Postcontrast MRI also achieved higher overall sensitivity, specificity, and accuracy compared to postcontrast MDCT for focal and exclusively solid liver lesions (p<0.05). Combined and postcontrast Gd-EOB-DTPA-enhanced MRI provided significantly higher overall detection rate and diagnostic accuracy, including low inter-observer variability, compared to MDCT in a single centre study.
    European journal of radiology 08/2013; · 2.65 Impact Factor
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    ABSTRACT: Background and Purpose: Mammographic breast density is the strongest known marker of breast cancer risk. Visual breast density assessment is subject to significant intra- and inter-rater variability. The aim of the present study was to test the reproducibility of automatic breast density assessment and to compare the results to the visual assessment.Patients and Methods: Serial mammograms of 141 patients were retrospectively reviewed. Breast density was assessed both visually using a BI-RADS four-category breast density scale and with a software tool for volumetric breast density measurement.Results: The intra- and inter-rater reproducibility as well as inter-examination reproducibility were assessed for both techniques by calculating the intraclass correlation coefficient (ICC). The inter-examination reproducibility of the volumetric measurement of breast percent density was 0.91 (ICC; 95 % CI 0.87 - 0.93). There was no difference in the strength of the correlation between patients with a large vs. small difference in compression force. The intra- and inter-rater reproducibility ranged from 0.81 - 0.84 and 0.71 - 0.77, respectively. The inter-examination reproducibility of visual assessment was 0.75 - 0.81. The agreement of visual assessment with volumetric measurement was similar to the agreement among readers.Conclusion: Our results indicate that volumetric breast density measurement provides higher reproducibility in serial examinations than visual assessment and may thus be preferable in the longitudinal assessment of breast density and in the measurement of breast density for risk stratification.Citation Format:
    RöFo - Fortschritte auf dem Gebiet der R 07/2013; · 2.76 Impact Factor
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    ABSTRACT: Volumetric breast composition analysis represents a useful tool for assessing changes in breast composition over time. However, no data exist on the reproducibility of this method in serial mammograms. To assess the reproducibility of two volumetric breast composition parameters, breast percent density (PD) and fibroglandular tissue volume (FTV), in consecutive mammograms. Volumetric breast composition analysis to determine PD and FTV was performed in two consecutive unilateral mammograms of 211 patients. All mammograms were obtained on the same digital mammography unit within a maximum interval of 24 months. Volumetric data for analysis for both examinations were available for 174 patients. Thirty-two patients had successful volumetric analysis of additional consecutive examinations on a second digital mammography unit. Inter-examination correlation of measurements and absolute differences were analyzed. Bland-Altman analysis was performed to compare readings from different mammography units. Mean FTV remained constant over the study period. A reduction in PD of 0.5% and a mean increase in breast volume (BV) of 3% were observed. FTV measurements obtained on the same mammography unit were significantly more reproducible than PD measurements (Pearson correlation coefficients of 0.947 and 0.920, respectively; P < 0.05). A 15% difference between mean absolute volume measurements (FTV and BV) obtained on different mammography units was observed (P ≤ 0.001), while mean PD was close to the expected value. Volumetric breast composition analysis is highly reproducible in serial mammograms in normal women. FTV is a more reproducible parameter than PD, indicating that absolute quantification of breast parenchyma may be preferable to the measurement of relative parameters such as PD. However, a disadvantage of using FTV is that it is susceptible to systematic differences when measurements are obtained on different imaging platforms.
    Acta Radiologica 07/2013; · 1.33 Impact Factor
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    ABSTRACT: To evaluate the accuracy, safety and efficacy of magnetic resonance imaging (MRI)-guided facet joint injection therapy using a 1.0-T open MRI. One hundred and sixty-six facet joint blocks in 45 patients with lower back pain were performed under MR fluoroscopic guidance using a proton-density-weighted turbo-spin-echo sequence. An in-room monitor, wireless MR-mouse for operator-controlled multiplanar navigation, a flexible surface coil and MR-compatible 20-G needle were used. Clinical outcome was evaluated by questionnaire before intervention and after 1 week, 3, 6 and 12 months using a numerical visual analogue scale (VAS). All facet joint blocks were considered technically successful with distribution of the injectant within and/or around the targeted facet joint. No major complications occurred. The final outcome analysis included 38 patients. An immediate effect was reported by 63 % of the patients. A positive mid-/long-term effect was seen in 13 patients (34 %) after 6 months and in 9 patients (24 %) after 12 months. Mean VAS was reduced from 7.1 ± 1.7 (baseline) to 3.5 ± 2.2, 4.1 ± 3.0, 3.8 ± 2.9 and 4.6 ± 2.9 at 1 week, 3, 6 and 12 months (P < 0.01). MR-guided facet joint injection therapy of the lumbosacral spine is accurate, safe and efficient in the symptomatic treatment of lower back pain. • MR-guided facet joint infiltration provides an alternative to CT and conventional fluoroscopy. • Clinical outcomes are comparable with conventional fluoroscopy and CT-guided facet joint interventions. • Ionising radiation can be avoided for both patient and physician. • MR-guided facet joint injection provides safe and effective treatment of back pain.
    European Radiology 06/2013; · 4.34 Impact Factor
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    ABSTRACT: OBJECTIVES: To assess the feasibility, safety and efficacy of real-time MR guidance and thermometry of percutaneous laser disc decompression (PLDD). METHODS: Twenty-four discs in 22 patients with chronic low-back and radicular pain were treated by PLDD using open 1.0-T magnetic-resonance imaging (MRI). A fluoroscopic proton-density-weighted turbo spin-echo (PDw TSE) sequence was used to position the laser fibre. Non-spoiled gradient-echo (GRE) sequences were employed for real-time thermal monitoring based on proton resonance frequency (PRF). Radicular pain was assessed over 6 months with a numerical rating scale (NRS). RESULTS: PLDD was technically successful in all cases, with adequate image quality for laser positioning. The PRF-based real-time temperature monitoring was found to be feasible in practice. After 6 months, 21 % reported complete remission of radicular pain, 63 % at least great pain relief and 74 % at least mild relief. We found a significant decrease in the NRS score between the pre-intervention and the 6-month follow-up assessment (P < 0.001). No major complications occurred; the single adverse event recorded, moderate motor impairment, resolved. CONCLUSIONS: Real-time MR guidance and PRF-based thermometry of PLDD in the lumbar spine under open 1.0-T MRI appears feasible, safe and effective and may pave the way to more precise operating procedures. KEY POINTS: • Percutaneous laser disc decompression (PLDD) is increasingly used instead of conventional surgery. • Open 1.0-T MRI with temperature mapping seems technically successful in monitoring PLDD. • Pain relief was at least 'great' in 64 % of patients. • No major complications occurred. • Open 1.0-T MRI appears a safe and effective option for patient-tailored PLDD.
    European Radiology 05/2013; · 4.34 Impact Factor
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    ABSTRACT: OBJECTIVES: The objective of this study was to evaluate the accuracy, safety, and efficacy of magnetic resonance (MR)-guided periradicular nerve root injection therapy using an open 1.0-T magnetic resonance imaging (MRI) system with fast dynamic imaging. MATERIALS AND METHODS: Between April 2008 and November 2011, a total of 249 MR-guided periradicular nerve root injections were performed in 141 patients experiencing lumbosacral radicular pain. All interventions were performed in an open 1.0-T MRI system. An interactive proton-density-weighted fast spin-echo sequence was used for real-time guidance. An in-room monitor, a wireless MR mouse for operator-controlled multiplanar imaging, a flexible surface coil, and an MR-compatible 20-G needle were used. Informed consent was obtained from all patients. Clinical outcome was evaluated through clinical follow-up and a questionnaire before injection therapy (baseline) and 6 months after using a numeric visual analog scale. RESULTS: All procedures were technically successful. No major complications occurred. At 6 months, of the 103 patients (197 injections; 57 men, 46 women; mean age, 49.5 years; range, 20-80) who enrolled in the outcome analysis, 14.6% reported complete remission of radicular pain; 53.4%, significant relief of pain; 22.3%, mild relief; and 9.7%, no relief of pain. We found a significant decrease of the visual analog scale score from the preintervention compared with the follow-up after 6 months (P < 0.001). No significant difference in the outcome was observed between the patients with degenerative foraminal stenoses and the patients with herniated disks. CONCLUSIONS: Magnetic resonance fluoroscopy-guided periradicular injection therapy for the lumbosacral spine under open 1.0-T MRI guidance is accurate, safe, and efficient in the symptomatic treatment of radicular pain. This technique may be a promising alternative to fluoroscopy- or computed tomography-guided spinal injections in the lumbosacral region, especially for young patients and patients undergoing serial therapeutic regimens.
    Investigative radiology 02/2013; · 4.85 Impact Factor
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    ABSTRACT: INTRODUCTION: The aim of this study was to assess a novel approach for the quantification of finger joint space narrowing and joint destruction in patients with rheumatoid arthritis (RA) focusing on the peripheral hand articulations. METHODS: 280 patients with verified RA underwent computerized semi-automated measurements of joint space distance at the finger-articulations based on radiographs. The Z-Score, which can differentiate between joint space alterations caused by RA versus age/gender-related changes, was calculated as a comparative parameter. The severity of joint space narrowing was also quantified by the Sharp Score. Sensitivity and specificity of the Z-Score (based on joint space widths differentiated for each peripheral finger joint) were evaluated to reveal the potential for the occurrence of erosions. Additionally, the potential of the Z-Score regarding the differentiation of therapeutic effects on joint space widths in patients under a therapy of methotrexate versus leflunomide was performed. RESULTS: The Z-Scores of finger articulations in patients with RA were generally decreased. MCP-articulations showed a continuous significant decline of -1.65+/-0.30 SD dependent on Sharp Score. The PIP-joints also revealed a significant reduction of the Z-Score (-0.96+/-0.31 SD). The sensitivity and specificity of JSD-MCP for the detection of erosions was 85.4% versus 55.2 %. The Sharp joint space narrowing score was not able to detect different treatments, whereas an accentuated stabilization of joint space narrowing could be identified for the Z-Score of the MCP-joints in patients treated with leflunomide and methotrexate. CONCLUSIONS: The Z-Scoring method based on computer-aided analysis of joint space widths was able to reliably quantify severity-dependent joint space narrowing in RA patients. In the future calculation of a Z-Score based on gender- and age-specific reference data shows the potential for a surrogate marker of RA progression which comprehends the early identification of patients with RA and in particular those with erosive course of the disease, enabling a timely therapeutic strategy for cartilage protection.
    Arthritis research & therapy 02/2013; 15(1):R27. · 4.27 Impact Factor
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    ABSTRACT: OBJECTIVES: To compare the costs of CT- and MR-guided lumbosacral nerve root infiltration for minimally invasive treatment of low back pain and radicular pain. METHODS: Ninety patients (54 men, 36 women; mean age, 45.5 ± 12.8 years) underwent MR-guided single-site periradicular lumbosacral nerve root infiltration with 40 mg of triamcinolone acetonide. A further 91 patients (48 men, 43 women; mean age, 59.1 ± 13.8 years) were treated under CT fluoroscopy guidance. Prorated costs of equipment use (purchase, depreciation and maintenance), staff costs based on involvement times and expenditure for disposables were identified for MR- and CT-guided procedures. RESULTS: Mean intervention time was 20.6 min (14-30 min) for MR-guided and 14.3 min (7-32 min) for CT-guided treatment. The average total costs per patient were 177 for MR-guided and 88 for CT-guided interventions. These consisted of (MR/CT guidance) 93/29 for equipment use, 43/35 for staff and 41/24 for disposables. CONCLUSIONS: Lumbosacral nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. Given the advantages of no radiation exposure and possible future decrease in prices for MRI devices and MR-compatible injection needles, MR-guided nerve root infiltration may become a promising alternative to the CT-guided procedure. KEY POINTS : • MR-guided nerve root infiltration therapy is now technically and clinically established. • Costs using MRI guidance are still about double those for CT guidance. • MR guidance involves no radiation exposure to patients and personnel. • MR-guided nerve root infiltration may become a promising alternative to CT.
    European Radiology 01/2013; · 4.34 Impact Factor
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    ABSTRACT: OBJECTIVES: Assessment of contrast agent kinetics in contrast-enhanced MRI (CE-MRI) with gadolinium-containing contrast agents offers the opportunity to predict breast lesion malignancy. The goal of our study was to determine if similar patterns exist for spectral contrast-enhanced digital breast tomosynthesis (CE-DBT) using an iodinated contrast agent. METHODS: The protocol of our prospective study was approved by the relevant institutional review board and the German Federal Office for Radiation Protection. All patients provided written informed consent. We included 21 women with a mean age of 62.4 years. All underwent ultrasound-guided biopsy of a suspect breast lesion, spectral CE-DBT and CE-MRI. For every breast lesion, contrast agent kinetics was assessed by signal intensity-time curves for spectral CE-DBT and CE-MRI. Statistical comparison used Cohen's kappa and Spearman's rho test. RESULTS: Spearman's rho of 0.49 showed significant (P = 0.036) correlation regarding the contrast agent kinetics in signal intensity-time curves for spectral CE-DBT and CE-MRI. Cohen's kappa indicated moderate agreement (kappa = 0.438). CONCLUSION: There is a statistically significant correlation between contrast agent kinetics in the signal intensity-time curves for spectral CE-DBT and CE-MRI. Observing intralesional contrast agent kinetics in spectral CE-DBT may aid evaluation of malignant breast lesions. KEY POINTS : • Contrast agent kinetics can be assessed using spectral digital breast tomosynthesis (DBT). • Contrast agent kinetics patterns in spectral DBT are similar to those in contrast-enhanced MRI. • Multiple contrast enhancement for spectral DBT gives additional diagnostic information.
    European Radiology 01/2013; · 4.34 Impact Factor
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    ABSTRACT: Objectif L’analyse de l’interligne articulaire assistée par ordinateur (CAJSA) est une technique nouvellement développée, afin de mesurer la largeur de l’interligne articulaire radiogéométriquement des métacarpo-phalangiennes (JSD-MCP) et des interphalangiennes proximales (JSD-PIP). Le but de cette étude était de vérifier la sensibilité et la spécificité des mesures CAJSA dans l’évaluation des polyarthrites rhumatoïdes (PR) établies. Méthodes Quatre cent cinquante-huit participants (248 sujets sains et 210 patients présentant une PR) ont subi une mesure semi-automatique des JSD-MCP et JSD-PIP en utilisant un kit de radiogrammétrie CAJSA, version 1.3.6, en se basant sur des radiographies numérisées. Une évaluation du score de Sharp a été effectuée afin de déterminer un éventuel pincement de l’interligne articulaire. Résultats La réduction dépendant de la sévérité de la maladie était de –44,0 % pour le score JSD-MCP et de –26,5 % pour le score JSD-PIP entre les scores Sharp 0 et 3. La sensibilité et la spécificité du JSC-MCP (total) étaient respectivement de 88,1 % versus 77,8 % (aire sous la courbe [AUC] = 0,920 ; p < 0,001). Le JSD-PIP (total) avait révélé une sensibilité et spécificité plus basses avec des valeurs respectives de 61,4 % et de 88,7 % (AUC = 0,878 ; p < 0,001). Conclusion La méthode CAJSA est fiable pour l’évaluation du pincement radiographique chez les patients souffrant de PR, avec une excellente sensibilité/spécificité. En fournissant des données quantitatives, d’autres méthodes de cotation pourraient être significativement améliorées, permettant une meilleure précision diagnostique et une meilleure évaluation thérapeutique.
    Revue du Rhumatisme. 01/2013; 80(5):473–478.

Publication Stats

175 Citations
133.11 Total Impact Points

Institutions

  • 2014
    • Humboldt-Universität zu Berlin
      Berlín, Berlin, Germany
  • 2012
    • Freie Universität Berlin
      Berlín, Berlin, Germany
  • 2010–2012
    • Charité Universitätsmedizin Berlin
      Berlín, Berlin, Germany
  • 2007–2012
    • Friedrich-Schiller-University Jena
      • Institute of Diagnostic and Interventional Radiology
      Jena, Thuringia, Germany