91 results on '"Dreher C"'
Search Results
2. MR-guided adaptive versus ITV-based stereotactic body radiotherapy for hepatic metastases (MAESTRO): a randomized controlled phase II trial
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Hoegen, P., Zhang, K. S., Tonndorf-Martini, E., Weykamp, F., Regnery, S., Naumann, P., Lang, K., Ristau, J., Körber, S. A., Dreher, C., Buchele, C., Rippke, C., Renkamp, C. K., Paul, K. M., König, L., Büsch, C., Krisam, J., Sedlaczek, O., Schlemmer, H.-P., Niyazi, M., Corradini, S., Debus, J., Klüter, S., and Hörner-Rieber, J.
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- 2022
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3. Früherkennung und Screening für die onkologische Prävention
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Dreher, C. and Bickelhaupt, S.
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- 2020
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4. Genomic analysis of perinatal sucking reflex in German Brown Swiss calves
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Dreher, C., Wellmann, R., Stratz, P., Schmid, M., Preuß, S., Hamann, H., and Bennewitz, J.
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- 2019
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5. Cyanobacteria-ferrihydrite aggregates, BIF sedimentation and implications for Archaean-Palaeoproterozoic seawater geochemistry.
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Li, Y., Sutherland, B. R., Ilin, A. M., Schad, M., Robbins, L. J., Kappler, A., Yusta, I., Sánchez-España, J., Owttrim, G. W., Dreher, C. L., Smith, A. J. B., Alessi, D. S., Gingras, M. K., and Konhauser, K. O.
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BANDED iron formations ,OCEAN waves ,MINERAL aggregates ,MARINE sediments ,OCEAN currents - Abstract
Precambrian banded iron formations (BIFs) are iron- and silica-rich (bio)chemical sediments that are widely believed to have been precipitated by microbial oxidation of dissolved Fe(II). The by-product of these metabolisms - insoluble ferric iron - would have settled through the water column, often as aggregates with the cell biomass. While the mineralogy, composition and physical properties of cell-iron mineral aggregates formed by anaerobic Fe(II)-oxidising photoferrotrophic bacteria have been extensively studied, there are limited studies that characterise cyanobacteriairon mineral aggregates that formed during oxygenic photosynthesis. This gap in knowledge is important because it impacts sedimentation velocities and the Fe(III) to organic carbon (C
org ) ratios in the marine sediment pile. Here, we used a recently introduced approach to precisely measure the sedimentation velocity of cyanobacteria-ferrihydrite aggregates and the Fe(III):Corg ratios of the cyanobacteria-ferrihydrite aggregates over a wide range of pH and initial Fe(II) concentrations under predicted Palaeoproterozoic atmospheric conditions. Our results indicate that it was highly unlikely BIFs formed at pH <7 via chemical oxidation due to the insufficient sedimentation velocity, even at the maximum predicted Fe(II) concentration of 1800 µM with excess oxygen. Instead, large Banded Iron Formation (BIF) deposits, such as those associated with the ca. 2.47 Ga Kuruman Formation in South Africa, would only had been deposited at minimum Fe(II) concentrations of 500 mM at pH 7 or 250 mM at pH 8. The Fe:Corg ratios in cyanobacteriaferrihydrite sediments formed during initially anoxic Fe(II) oxidation experiments represent the maximum values under each condition because we specifically extracted samples after all Fe(II) was oxidised. The Fe(III) to organic carbon ratio was consistently below 4, which is also the ratio required for dissimilatory Fe(III) reduction (DIR). This result indicates that biomass in this case was in excess, which contradicts the low organic carbon content seen in most BIFs. Thus, we suggest that biomass was either physically separated from ferrihydrite aggregates during sedimentation under the influence of ocean currents and waves, or it was degraded prior to DIR. The mineralogical and geochemical evidences of both oxide and carbonate facies from the Kuruman Iron Formation (IF) suggest that ferrihydrite was most likely the precursor along with a significant initial organic carbon input, supporting the proposed cyanobacterially-mediated BIF depositional model and experimental results. [ABSTRACT FROM AUTHOR]- Published
- 2024
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6. Diffusionsbildgebung – diagnostische Erweiterung oder Ersatz von Kontrastmitteln in der Früherkennung von Malignomen?
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Bickelhaupt, S., Dreher, C., König, F., Deike-Hofmann, K., Paech, D., Schlemmer, H. P., and Kuder, T. A.
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- 2019
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7. Exploring MR regression patterns in rectal cancer during neoadjuvant radiochemotherapy with daily T2- and diffusion-weighted MRI
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Bostel, T., Dreher, C., Wollschläger, D., Mayer, A., König, F., Bickelhaupt, S., Schlemmer, H. P., Huber, P. E., Sterzing, F., Bäumer, P., Debus, J., and Nicolay, N. H.
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- 2020
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8. Diffusion-weighted breast imaging
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Deike-Hofmann, K., Kuder, T., König, F., Paech, D., Dreher, C., Delorme, S., Schlemmer, H.‑P., and Bickelhaupt, S.
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- 2018
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9. Radiomics in diffusion data: a test–retest, inter- and intra-reader DWI phantom study
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Dreher, C., Kuder, T.A., König, F., Mlynarska-Bujny, A., Tenconi, C., Paech, D., Schlemmer, H.-P., Ladd, M.E., and Bickelhaupt, S.
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- 2020
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10. PO-1099: Response prediction by daily fractional MRI during neoadjuvant radiochemotherapy in rectal cancer
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Bostel, T., Dreher, C., Wollschläger, D., Mayer, A., Bickelhaupt, S., Schlemmer, H., Huber, P., Sterzing, F., Debus, J., and Nicolay, N.
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- 2020
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11. PD-0298: Long-term characterization of MRImorphologic alterations after active motion-compensated liver SBRT
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Miebach, G., Dreher, C., Wojtal, P., Oppitz, H., Jahnke, A., Sarria, G., Giordano, F.A., Blanck, O., and Boda-Heggemann, J.
- Published
- 2020
- Full Text
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12. Multiplicities in highp t hadron-nucleus interactions
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Bärwolff, H., Bohm, G., Dreher, C., Friebel, W., Gensch, U., Meyer, A., Naumann, T., Roloff, H., Spiering, C., Denes, E., Diosy, L., Gemesy, T., Jenik, L., Krasznovsky, J., Pinter, Gy., Wagner, I., Bannikov, A. V., Böhm, J., Grishkevich, Ya. V., Khomenko, B. A., Krumstein, Z. V., Merekov, Yu. P., Petrukhin, V. I., Piska, K., Safarik, K., Shelkov, G. A., Tkachev, L. G., Vertogradov, L. S., Soukup, T., Valkarova, A., Valkar, S., Zavada, P., Penev, V. N., Shklovskaya, A. I., Javrishvili, A. K., Kharchilava, A. I., Lomtadze, T. A., Razdolskaya, L. A., Dominik, W., Gajewski, J., Majewski, S., Pniewska, K., Ropelewski, L., Zakrzewski, J. A., and RISK Collaboration
- Published
- 1986
- Full Text
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13. Charge and energy flow in π+ p,K + p andpp interactions at 250 GeV/c
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Ajinenko, I. V., Baladyan, S. G., Belokopytov, Yu. A., Böttcher, H., Botterweck, F., Chliapnikov, P. V., Crijns, F., De Roeck, A., De Wolf, E. A., Dreher, C., Dziunikowska, K., Ermolov, P. F., Garutchava, Z. C., Gerdyukov, L. N., Gevorkyan, G. V., Grässler, H., van Hal, P., Haupt, T., Kittel, W., Meijers, F., Michałowska, A. B., Nikolaenko, V. I., Oliveira, L. C., Olkiewicz, K., Pöllänen, R., Ronjin, V. M., Rybin, A. M., Saarikko, H. M. T., Schmitz, W., Scholten, L., Shabalina, E. K., Stepaniak, J., Tchikilev, O. G., Tomaradze, A. G., Uvarov, V. A., Verbeure, F., Wischnewski, R., Yarba, Yu. V., Zielinski, W., and EHS-NA22 Collaboration
- Published
- 1989
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14. Inclusive π0 production in π+ p,K + p andpp interactions at 250 GeV/c
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Aiinenko, I. V., Atayan, M. R., Belokopytov, Yu. A., Białkowska, H., Boettcher, H., Brun, R., Chliapnikov, P. V., Crijns, F., De Roeck, A., De Wolf, E. A., Dreher, C., Dziunikowska, K., Endler, A. M. F., Friebel, W., Gevorkyan, G. V., Graessler, H., Gumenyuk, S. A., van Hal, P., Hrubec, J., Karamyan, J. K., Kistenev, E. P., Kittel, W., Kowalski, M., Kurnosenko, A. I., Meijers, F., Minaev, N. G., Michałowska, A. B., Neuhofer, G., Nikolaenko, V. I., Oliveira, L. C. S., Olkiewicz, K., Petrovykh, L. P., Riipinen, E., Rybin, A. M., Saarikko, H. M. T., Saarikko, Y. T. M., Schmitz, P., Schmitz, W., Scholten, L., Sotnikova, N. A., Stepaniak, J., Stergiou, A., Stopchenko, V. A., Tchikilev, O. G., Tikhonova, L. A., Toet, D., Uvarov, V. A., Verbeure, F., Vorobjev, A. P., Wischnewski, R., Wróblewski, A., Zotkin, S. A., and NA22 Collaboration
- Published
- 1987
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15. Charge and energy flow in π p, K p and pp interactions at 250 GeV/c.
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Ajinenko, I., Baladyan, S., Belokopytov, Yu., Böttcher, H., Botterweck, F., Chliapnikov, P., Crijns, F., Roeck, A., Wolf, E., Dreher, C., Dziunikowska, K., Ermolov, P., Garutchava, Z., Gerdyukov, L., Gevorkyan, G., Grässler, H., Hal, P., Haupt, T., Kittel, W., and Meijers, F.
- Abstract
We present data on the flow of energy and charge in π p, K p and pp interactions at 250 GeV/c. The energy and charge flow in the beam c.m. hemisphere is analysed in terms of the cluster-invariant Bialas-Ochs-Stodolsky variable λ=cot θ/ E . The profile functions dQ/dλ and dE/dλ indicate a widening in p of jets between 32 and 250 GeV/c incident laboratory momentum, whereas the ratio dQ/dE is energy independent. The data are compared to μ p deep-inelastic scattering resutls and to expectations from the single string LUND model, the Dual Parton Model and the two-string LUND model (FRITIOF). [ABSTRACT FROM AUTHOR]
- Published
- 1989
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16. Neutral strange particle production in high transverse momentum π nucleus interactions at ∼40 GeV/c.
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Bärwolff, H., Dreher, C., Friebel, W., Gensch, U., Roloff, H., Schreiber, H., Spiering, C., Denes, E., Diosi, L., Gemesy, T., Jenik, L., Krasznovsky, J., Pinter, Gy., Wagner, I., Bannikov, A., Boehm, J., Grishkevich, Yu., Khomenko, B., Krumstein, Z., and Merekov, Yu.
- Abstract
Measurements of K, Λ and $$\bar \Lambda $$ production in π nucleus (C, Cu, Pb) interactions are presented. The experiment was carried out with the streamer chamber spectrometer RISK using a π beam of ∼40 GeV/c and a trigger requiring a secondary charged particle with transverse momentum above 1.1 GeV/c. Production cross sections, relative production rates and distributions of Feynman x and transverse momentum squared as well as correlations between the V and the trigger particle are presented. The results are compared and found to be in agreement with K, Λ and $$\bar \Lambda $$ data from untriggered π p and π C interactions, except for the relative production rate of antilambdas which is about to times larger in high- p collisions. Our results can be well interpreted within the dual topological unitarization model. [ABSTRACT FROM AUTHOR]
- Published
- 1988
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17. Inclusive π production in π p, K p and pp interactions at 250 GeV/c.
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Aiinenko, I., Atayan, M., Belokopytov, Yu., Białkowska, H., Boettcher, H., Brun, R., Chliapnikov, P., Crijns, F., Roeck, A., Wolf, E., Dreher, C., Dziunikowska, K., Endler, A., Friebel, W., Gevorkyan, G., Graessler, H., Gumenyuk, S., Hal, P., Hrubec, J., and Karamyan, J.
- Abstract
Data are presented on inclusive π production in the forward c.m. hemisphere ( x>0.025) in π p, K p and pp interactions at 250 GeV/c. These data are compared to results at other energies and interpreted in terms of quark-parton models. [ABSTRACT FROM AUTHOR]
- Published
- 1987
- Full Text
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18. Multiplicities in high p hadron-nucleus interactions.
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Bärwolff, H., Bohm, G., Dreher, C., Friebel, W., Gensch, U., Meyer, A., Naumann, T., Roloff, H., Spiering, C., Denes, E., Diosy, L., Gemesy, T., Jenik, L., Krasznovsky, J., Pinter, Gy., Wagner, I., Bannikov, A., Böhm, J., Grishkevich, Ya., and Khomenko, B.
- Abstract
We present results obtained in π A ( A=C, Cu, Pb) - collisions at 38 GeV/c. A single particle trigger selects events with one charged particle in the central region and large transverse momentum. The effect of this trigger on the multiplicities of all charged particles and of protons is shown. [ABSTRACT FROM AUTHOR]
- Published
- 1986
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19. Broadcast Control Operation.
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Dreher, C.
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- 1928
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20. An Oscillation Source for Radio Receiver Investigations.
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Weinberger, J. and Dreher, C.
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- 1919
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21. Reply to Basu.
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Dreher, C.
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LETTERS , *COMPUTER software - Abstract
A response to a letter about the implementation of the Hoffer-Q formula in the IOLMaster software is presented.
- Published
- 2007
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22. ChemInform Abstract: Metal Complexes with Tetrapyrrole Ligands. Part 48. Vilsmeier Formylation of Metal Porphyrins of Co(II), Ni(II), Pd(II), Pt(II), Cu(II), Zn(II), Co(III), Cr(III), Mn(III), Fe(III), Al(III), Si(IV), and Pt(IV) and Its Dependence on the Central Metal.
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BUCHLER, J. W., DREHER, C., and HERGET, G.
- Published
- 1988
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23. ChemInform Abstract: Synthesis and Coordination Chemistry of Noble Metal Porphyrins.
- Author
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BUCHLER, J. W., DREHER, C., and KUENZEL, F. M.
- Published
- 1996
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24. Automatic referral to genetic counseling for identification of BRCA1/2 mutations: a pilot program at Norton Cancer Institute, Louisville, KY.
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Lewis, A. L., Alabek, M. L., Dreher, C., Goldberg, J. M., and Brooks, S. E.
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CANCER research , *CANCER genetics , *CANCER treatment , *CANCER prevention , *CANCER diagnosis , *GENETIC counseling , *BRCA genes - Abstract
BACKGROUND: Identifying a hereditary cancer syndrome has the potential to significantly impact a patient's treatment and long-term management, as well as prevent future malignancies among relatives. Therefore, referral of patients appropriate for genetic counseling and testing is critical. Providers traditionally initiate patient referral; however, this can lead to inconsistent referrals and results in failure to refer more than 50% of appropriate individuals, according to recent studies. In an attempt to address these quality issues, we developed an automatic referral program using the National Comprehensive Cancer Network guidelines, which was approved through our cancer committee and implemented 10/1/10. This pilot was conducted within a genetic counseling program staffed by board certified genetic counselors and associated with a private, multi-disciplinary oncology practice that is part of an American College of Surgeons accredited Network Cancer Center. Our Cancer Center is part of a five-hospital integrated healthcare system and a part of the National Cancer Institute Community Cancer Centers Program network. METHODS: We conducted weekly reviews of oncology patients scheduled for upcoming appointments to identify individuals diagnosed with breast cancer before age 50 or with ovarian, fallopian, or primary peritoneal cancer at any age. Patients previously referred to our genetic counseling program were excluded. Providers were notified weekly of their patients identified via this program, with the option to decline referral. We undertook a retrospective review of the outcomes of individuals identified from 10/1/10 through 10/1/11, with follow up as of 6/1/12. IRB approval was obtained through the University of Louisville. RESULTS: We identified 521 patients for referral, 24 (4.6%) of whom were declined by a provider, resulting in 497 referrals. Three hundred forty one (69%) referrals had breast cancer and 156 (31%) had other malignancies. Of referrals, 139 (28%) have been seen, 223 (45%) have declined, and 135 (27%) are in process. Testing was pursued by 108 (78%) of referrals seen, all of whom had BRCA1/2 testing and 5 (4.6%) of whom had additional testing. We identified 11 (10%) individuals with a BRCA1/2 mutation. An additional 17 (16%) individuals who completed testing were counseled to consider enhanced surveillance in the absence of a confirmed hereditary cancer syndrome. The total number of first degree relatives with potential to benefit from this program is 62 among individuals with a BRCA1/2 mutation and 86 among individuals without a confirmed hereditary cancer syndrome. CONCLUSIONS: Initiation of an automatic genetic counseling referral program in the setting of a large oncology practice is feasible and has the potential to identify individuals with a BRCA1/2 mutation who might otherwise go undetected. Few providers object to referral, and the majority of patients are receptive to referral. The impact of this program extends beyond those identified with a BRCA1/2 mutation. This project was funded in part with federal funds: NCI, NIH Contract No. HHSN261200800001E. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
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25. Is digital psychiatry really for all? A cross-sectional analysis from two randomized clinical trials.
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Gallois C, Machado M, Oliveira C, Xavier ACM, Dreher C, and Manfro GG
- Abstract
Introduction: Digital psychiatry holds promise for expanding accessibility to mental health treatment, but concerns exist regarding its inclusivity and the potential for exacerbation of digital exclusion among vulnerable populations. This study aims to evaluate the inclusivity of digital psychiatry research and interventions, and to explore their potential to worsen digital exclusion., Methods: We conducted a cross-sectional analysis of sociodemographic data from two clinical trials that utilize psychiatric online treatment modalities in Brazil. Participants were recruited nationwide through digital media platforms., Results: The sample comprised 224 individuals, predominantly female (95.1%) and Caucasian (71.87%) participants, with an average of 15.12 years of schooling. It was observed that White individuals were overrepresented compared to national averages (42.8%). Additionally, participants had a higher average number of years of schooling compared to the national average (10.1 years). Our analysis revealed a clear profile among psychiatric patients with access to and interest in digital interventions, predominantly younger, White, educated, and female individuals., Discussion: As digital therapeutic solutions advance, ensuring their inclusivity and accessibility for vulnerable individuals is crucial. Initiatives to promote digital inclusion and reassess participant recruitment strategies are needed to effectively address digital exclusion. By adopting multifaceted approaches, digital mental health care can be made more effective and accessible to all., Competing Interests: No conflicts of interest declared concerning the publication of this article.
- Published
- 2024
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26. Pituitary metastasis arising from hepatocellular carcinoma: a case report and update of the literature.
- Author
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Rodriguez I, Vogel L, Dreher C, Cherkezov A, Giordano F, Frölich M, Ebert MP, Teufel A, and Boda-Heggemann J
- Subjects
- Humans, Female, Aged, Diagnosis, Differential, Treatment Outcome, Liver Neoplasms secondary, Liver Neoplasms diagnosis, Liver Neoplasms pathology, Carcinoma, Hepatocellular secondary, Carcinoma, Hepatocellular pathology, Pituitary Neoplasms secondary, Pituitary Neoplasms pathology, Pituitary Neoplasms therapy, Pituitary Neoplasms diagnosis
- Abstract
Hepatocellular carcinoma (HCC) is the sixth most common neoplasia and the third leading cause of cancer-associated deaths worldwide. Most cases arise in patients with cirrhosis, and early detection through periodic screening can make it potentially curable. The presence of extrahepatic metastases (EHM) affects treatment decisions and curability. The lungs are the most common site for EHM, followed by lymph nodes, bones, and the adrenal glands. Interestingly, approximately only 15 cases of HCC metastasizing to the pituitary gland have been reported so far.The most common symptoms of pituitary metastasis (PM) arising from HCC are nerve palsies affecting the third, fourth, and sixth cranial nerves. Other symptoms, such as diabetes insipidus or pituitary insufficiencies, are present in a minority of cases. Detecting PM is difficult given its rarity. Gold-standard treatments for these patients have not yet been established, but the prognosis is dismal, with a median overall survival of only 4.5 months. In this paper, we present an interesting case of PM as the first symptom of an HCC in a 75-year-old female. We also present an overview of all cases reported to date with emphasis on symptom presentation and survival after diagnosis.Given the improvement of systemic therapy, more cases are diagnosed in both oligometastatic and palliative conditions. Therefore, better approaches and treatment modalities for extrahepatic metastases due to HCC should be defined., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2024
- Full Text
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27. Evidence-based practice - implementation level and attitude among physical, occupational, and speech and language therapists in Germany: status quo.
- Author
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Reinecke S, Mijic M, Gerhard J, Jung A, Ernst K, Dreher C, Lohmann M, Koch M, Jahjah A, Fichtemüller A, and Balzer J
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- Humans, Germany, Cross-Sectional Studies, Male, Female, Adult, Surveys and Questionnaires, Occupational Therapists psychology, Middle Aged, Physical Therapists psychology, Physical Therapists education, Occupational Therapy education, Health Knowledge, Attitudes, Practice, Language Therapy methods, Evidence-Based Practice, Attitude of Health Personnel
- Abstract
Introduction: Evidence-based practice (EBP) is an important component of clinical practice in public health. Its implementation involves interpreting scientific studies and then applying this knowledge to clinical decision-making. In Germany, the therapy professions are often trained in non-academic medical schools, and only a small number of therapists are university graduates., Aims: This study assessed the current status of EBP among physiotherapists, occupational therapists, and speech and language therapists and to determine whether academization influences the implementation of EBP in Germany., Methods: To assess the EBP implementation level and therapists' attitudes toward EBP, a cross-sectional study was conducted using the German version of the Evidence-Based Practice Inventory (EBPI), which consists of five dimensions: attitude; subjective norm; perceived behavioral control; decision-making; and intention and behavior. The structural validity and internal consistency of the EBPI survey were also tested., Results: Of the 2,412 responses, only 557 were eligible. There were statistically significant differences between academically educated vs. non-academically educated therapists in four of the five EBPI dimensions. Furthermore, four of the five dimensions had sufficient unidimensionality and internal consistency., Conclusion: There are differences between academically educated and non-academically educated therapists regarding EBP knowledge, attitudes, and implementation. Academically educated therapists are more likely to use EBP than non-academically educated therapists. There are still barriers to clinical application that need to be addressed., Spanish Abstract: http://links.lww.com/IJEBH/A195., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 JBI. Unauthorized reproduction of this article is prohibited.)
- Published
- 2024
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28. Changes in Pulmonary Functions of Adolescents with Pectus Excavatum Throughout the Nuss Procedure.
- Author
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Dreher C, Reinsberg M, Oetzmann von Sochaczewski C, Siebert S, Strohm J, Kurz R, Ziegler AM, Heydweiller A, and Yavuz ST
- Subjects
- Humans, Male, Adolescent, Female, Lung, Vital Capacity, Lung Volume Measurements, Forced Expiratory Volume, Funnel Chest surgery
- Abstract
Background: We aimed to determine the longitudinal changes in pulmonary functions of adolescents with Pectus Excavatum who underwent the Nuss procedure, the minimally invasive repair of pectus excavatum (MIRPE)., Methods: Lung function measurements were performed before bar implantation (T
0 ), at least six weeks to ten months after implantation (T1a ), at least eleven months to sixty-one months after bar implantation (T1b ) and at least two weeks after bar explantation (T2 )., Results: Data of 114 patients (83.3% male) whose median age at implantation was 15.6 years and at explantation 18.7 years were analyzed. Shortly after implantation at T1a a significant decline of vital capacity (VC; n = 82), forced vital capacity (FVC; n = 78) and forced expiratory volume in 1 second (FEV1 ; n = 80) compared to T0 was seen. At T1b a significant decline for the residual volume (RV; n = 83), the residual volume/total lung capacity ratio (RV/TLC; n = 81), the total specific airway resistance (sRaw; n = 80) and the total airway resistance (Raw; n = 84) also compared to T0 was measured. In the comparison of T1 b to T2 a significant increase of VC, FVC (n = 67), FEV1 (n = 69), TLC (n = 67) and a significant decrease of Raw (n = 66), sRaw, RV (n = 65) and the RV/TLC (n = 64) ratio could be observed. In the direct analysis between T0 and T2 , after the explantation of the bar a significant increase in VC (n = 54), FVC (n = 52), and TLC (n = 55) and a significant decrease of RV (n = 51) and the RV/TLC index (n = 50), and in airway resistance parameters like Raw (n = 52) and sRaw (n = 51) could be detected., Conclusions: Lung function values along with markers of airway resistance improve in patients after the complete procedure of MIRPE., Level of Evidence: Level II., (Copyright © 2023 Elsevier Inc. All rights reserved.)- Published
- 2023
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29. Long-term characterization of MRI-morphologic alterations after active motion-compensated liver SBRT: a multi-institutional pooled analysis.
- Author
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Dreher C, Sarria GR, Miebach G, Weiss C, Buergy D, Wojtal P, Tavakoli AA, Krug D, Oppitz H, Giordano FA, Both M, Lohr F, Dunst J, Blanck O, and Boda-Heggemann J
- Subjects
- Humans, Retrospective Studies, Magnetic Resonance Imaging, Radiotherapy Dosage, Radiosurgery adverse effects, Radiosurgery methods, Liver Neoplasms diagnostic imaging, Liver Neoplasms radiotherapy, Liver Neoplasms pathology
- Abstract
Background: Stereotactic body radiotherapy (SBRT) is an effective therapeutic approach in patients with liver metastases. However, long-term changes in hepatic normal tissue have to be taken into account in multimodal treatment regimes. Magnetic-resonance-imaging (MRI) based morphologic liver alterations (MMA) after liver SBRT have been analyzed longitudinally., Material and Methods: 57 patients treated with gantry-based or robotic-based SBRT of 69 treatment volumes of liver metastases, who had long-term follow-up (FU) ≥6 months were included in this retrospective analysis. Post-SBRT MMAs were contoured on each contrast-enhanced-T1-weighted (T1w) MRI-sequence. Morphologic/volumetric data of the liver and MMAs were evaluated longitudinally, including the dependency on treatment-related factors of the planning target volume (PTV) and liver., Results: The median FU time was 1 year [6-48 months]. 66 of 69 treatment volumes developed MMAs (mean 143.8 ± 135.1 ccm at first appearance). 31.8% of MMAs resolved completely during FU. Of the persisting MMAs 82.2%/13.3% decreased/increased in size until last available FU. Morphological characterization of the MMAs at first appearance included 75% hypointense and 25% hyperintense T1w-MRI-based appearances. Hypointense as compared to hyperintense appearance was significantly associated with a higher mean liver dose EQD2
α/β=3 Gy ( p = 0.0212) and non-significantly greater MMA size. Variance analysis demonstrated a significant reduction of MMA and total liver volume after SBRT ( p < 0.0001). The volume reduction decelerated longitudinally for both MMA ( p < 0.0001) and liver size ( p = 0.0033). Radiation doses (PTV-BEDα/β=3 Gy and 10 Gy ) were not significantly associated with MMA volume reduction. SBRT of liver metastases with mean liver dose EQD2α/β=3 Gy > 18 Gy were characterized by greater MMA volumes ( p = 0.0826) and steeper MMA reduction gradients during FU than those with EQD2α/β=3 Gy ≤ 18 Gy ( p < 0.0001)., Conclusion: Radiogenic MMAs either completely resolve or usually decrease in volume with pronounced reduction during short-term FU. This course was independent of the MMA's morphological appearance. Further, increased mean liver dose was associated with greater MMA size and a greater gradient of MMA size reduction during FU.- Published
- 2023
- Full Text
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30. Pancreatic imaging using diffusivity mapping - Influence of sequence technique on qualitative and quantitative analysis.
- Author
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Tavakoli AA, Dreher C, Mlynarska A, Kuder TA, Gnirs R, Schlemmer HP, and Bickelhaupt S
- Subjects
- Diffusion Magnetic Resonance Imaging methods, Humans, Pancreas diagnostic imaging, Reproducibility of Results, Retrospective Studies, Artifacts, Echo-Planar Imaging methods
- Abstract
Purpose: To compare image quality of an optimized diffusion weighted imaging (DWI) sequence with advanced post-processing and motion correction (advanced-EPI) to a standard DWI protocol (standard-EPI) in pancreatic imaging., Materials and Methods: 62 consecutive patients underwent abdominal MRI at 1.5 T were included in this retrospective analysis of data collected as part of an IRB approved study. All patients received a standard-EPI and an advanced-EPI DWI with advanced post-processing and motion correction. Two blinded radiologists evaluated the parameters image quality, detail of parenchyma, sharpness of boundaries and discernibility from adjacent structures on b = 900 s/mm
2 images using a Likert-like scale. Segmentation of pancreatic head, body and tail were obtained and apparent diffusion coefficient (ADC) was calculated separately for each region. Apparent tissue-to-background ratio (TBR) was calculated at b = 50 s/mm2 and at b = 900 s/mm2 ., Results: The advanced-EPI yielded significantly higher scores for pancreatic parameters of image quality, detail level of parenchyma, sharpness of boundaries and discernibility from adjacent structures in comparison to standard-EPI (p < 0.001 for all, kappa = [0.46,0.71]) and was preferred in 96% of the cases when directly compared. ADC of the pancreas was 7% lower in advanced-EPI (1.236 ± 0.152 vs. 1.146 ± 0.126 μm2 /ms, p < 0.001). ADC in the pancreatic tail was significantly lower for both sequences compared to head and body (all p < 0.001). There was comparable TBR for both sequences at b = 50 s/mm2 (standard-EPI: 19.0 ± 5.9 vs. advanced-EPI: 19.0 ± 6.4, p = 0.96), whereas at b = 900 s/mm2 , TBR was 51% higher for advanced-EPI (standard-EPI: 7.1 ± 2.5 vs. advanced-EPI: 10.8 ± 5.1, p < 0.001)., Conclusion: An advanced DWI sequence might increase image quality for focused imaging of the pancreas and providing improved parenchymal detail levels compared to a standard DWI., (Copyright © 2021. Published by Elsevier Inc.)- Published
- 2022
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31. Predictors of Airway Hyperresponsiveness in Symptomatic Children with Normal Spirometry and Suspicious of Possible Asthma.
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Reinsberg M, Siebert S, Dreher C, Bogs T, Ganschow R, and Yavuz ST
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- Bronchial Provocation Tests, Child, Cough, Forced Expiratory Volume, Humans, Methacholine Chloride, Respiratory Sounds, Retrospective Studies, Spirometry, Asthma diagnosis, Asthma epidemiology, Bronchial Hyperreactivity diagnosis, Bronchial Hyperreactivity epidemiology, Respiratory Hypersensitivity
- Abstract
Background: Asthma diagnosis may be challenging particularly in patients with mild symptoms without an obstructive pattern in spirometry. Detection of airway hyperresponsiveness (AHR) by a positive methacholine challenge (MCC) is still an important diagnostic tool to confirm the presence of asthma with reasonable certainty. However, it is time consuming and could be exhausting for patients. We aimed to identify the predictive factors for AHR in children with respiratory symptoms without obstructive pattern in spirometry., Methods: Data from children who had undergone MCC were analyzed retrospectively. The demographic features of patients along with laboratory results were collected., Results: A total of 123 children with a median age of 10.5 years were enrolled. AHR was detected in 81 children (65.8%). The age of the children with AHR was significantly younger. The prevalences of aeroallergen sensitization, nocturnal cough, wheezing, and a baseline forced expiratory flow at 75% of vital capacity (FEF75) <65% were significantly more frequent in children with AHR. Multivariate logistic regression analysis revealed age, ever wheezing, nocturnal cough, tree pollen allergy, and FEF75 <65% as independent predictors of AHR. A weighted clinical risk score was developed (range, 0-75 points). At a cutoff point of 35, the presence of AHR is predicted with a specificity of 90.5% and a positive predictive value of 91.5%., Conclusion: In children suspected of having asthma, but without an obstructive pattern in the spirometry, combining independent predictors, which can be easily obtained in clinical practice, might be used to identify children with AHR., (© 2021 S. Karger AG, Basel.)
- Published
- 2022
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32. Beneficial effects of dynamic groundwater flow and redox conditions on Natural Attenuation of mono-, poly-, and NSO-heterocyclic hydrocarbons.
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Salowsky H, Schäfer W, Schneider AL, Müller A, Dreher C, and Tiehm A
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- Biodegradation, Environmental, Oxidation-Reduction, Groundwater, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
Natural Attenuation (NA) processes have been demonstrated to reduce pollutant loads at different contaminated groundwater sites world-wide and are increasingly considered in contaminated site management concepts. However, data are mainly available for steady state groundwater flow and stable redox conditions as well as pollutants listed in standard regulatory schemes. In this study, the influence of transient groundwater flow and redox conditions on NA was examined at a former gas works site near the river Rhine in Germany. The investigated 78 pollutants included 40 mono- and polyaromatic hydrocarbons (MAHs, PAHs) and 38 NSO-heterocyclic aromatic hydrocarbons (NSO-HET). In the highly polluted areas, the MAHs benzene, indene and indane, the PAHs naphthalene, acenaphthene, 1- and 2-methylnaphthalene and the NSO-HET 2-methylquinoline, carbazole, benzothiophene, dibenzofuran and benzofuran were predominant. Pollutant concentrations decreased with increasing distance from the sources of contamination. At the plume fringes, the MAHs benzene and indane, the PAH acenaphthene, the NSO-HET carbazole, 5-methylbenzothiophene, 2- and 3-methylbenzofuran and 2-methyldibenzofuran were predominant, indicating low retention and slow intrinsic biodegradation of these compounds. The influence of surface water on groundwater level, pollutant concentrations, and redox conditions in the monitoring wells was observed with a permanently installed groundwater sensor. The temporary availability of oxygen was observed at the plume fringes, resulting in aerobic and ferric iron reducing biodegradation processes. Field and laboratory data were used to set-up a groundwater flow and reactive transport model used for quantification of the field mass transfer rates. In conclusion, the study demonstrates that NA is effective under transient flow and redox conditions. A conceptual model and reactive transport simulation can facilitate the interpretation of pronounced fluctuations of pollutant concentration in monitoring wells. Based on the analysis of 78 pollutants, indane, indene and several NSO-HET like carbazole, benzothiophene and 2-methyldibenzofuran are recommended for monitoring at tar oil polluted sites, besides EPA-PAHs and BTEX., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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33. Promoting Integrated Care through a Global Treatment Budget: A Qualitative Study in German Mental Health Care using Rogers' Diffusion of Innovation Theory.
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Afraz FC, Vogel A, Dreher C, and Berghöfer A
- Abstract
Introduction: Since 2003, as a means of enabling integrated care the German mental health care system has offered the innovative option of agreeing a Global Treatment Budget (GTB, also known as a regional psychiatric budget or innovative flexible and integrative forms of treatment FIT) with health insurers and regional care providers across sectors. Despite promoting legal frameworks and positive evidence on improving quality of patient care, this model has not spread widely. The aim of this study is to identify inhibiting and facilitating factors for the innovation diffusion., Theory and Methods: We conducted expert interviews with 19 actors from nine German regions involved in GTBs, using a self-developed questionnaire based on Rogers' theory on innovation diffusion extended by the innovation system approach. Interviews were analysed applying qualitative content analysis. Code categories were built deductively operationalising Rogers' theory and inductively from the data generated., Results: Observability of the innovation was perceived as good, but trialability, reversibility, compatibility with regular care structures as low, and thus the perceived risks of adoption as high. Complexity up to implementation is high, caused by numerous individuals and stakeholder groups involved. Diffusion took place in environments of strong individuals with venturesomeness, opinion leadership, and informal networking. As favourable framework conditions the monopoly and non-profit position of hospitals in well-defined care regions were identified., Discussion and Conclusions: Diffusion of integrated care could be accelerated by dissolving the multi-actor constellation, changing the communication strategy, and adapting the legal framework., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2021 The Author(s).)
- Published
- 2021
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34. Liver SBRT with active motion-compensation results in excellent local control for liver oligometastases: An outcome analysis of a pooled multi-platform patient cohort.
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Stera S, Miebach G, Buergy D, Dreher C, Lohr F, Wurster S, Rödel C, Marcella S, Krug D, Frank A G, Ehmann M, Fleckenstein J, Blanck O, and Boda-Heggemann J
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- Follow-Up Studies, Humans, Liver, Retrospective Studies, Survival Rate, Radiosurgery adverse effects
- Abstract
Background: Local treatment of metastases in combination with systemic therapy can prolong survival of oligo-metastasized patients. To fully exploit this potential, safe and effective treatments are needed to ensure long-term metastases control. Stereotactic body radiotherapy (SBRT) is one means, however, for moving liver tumors correct delivery of high doses is challenging. After validating equal in-vivo treatment accuracy, we analyzed a pooled multi-platform liver-SBRT-database for clinical outcome., Methods: Local control (LC), progression-free interval (PFI), overall survival (OS), predictive factors and toxicity was evaluated in 135 patients with 227 metastases treated by gantry-based SBRT (deep-inspiratory breath-hold-gating; n = 71) and robotic-based SBRT (fiducial-tracking, n = 156) with mean gross tumor volume biological effective dose (GTV-BED
α/β=10Gy ) of 146.6 Gy10 ., Results: One-, and five-year LC was 90% and 68.7%, respectively. On multivariate analysis, LC was significantly predicted by colorectal histology (p = 0.006). Median OS was 20 months with one- and two-year OS of 67% and 37%. On multivariate analysis, ECOG-status (p = 0.003), simultaneous chemotherapy (p = 0.003), time from metastasis detection to SBRT-treatment (≥2months; p = 0.021) and LC of the treated metastases (≥12 months, p < 0.009) were significant predictors for OS. One- and two-year PFI were 30.5% and 14%. Acute toxicity was mild and rare (14.4% grade I, 2.3% grade II, 0.6% grade III). Chronic °III/IV toxicities occurred in 1.1%., Conclusions: Patient selection, time to treatment and sufficient doses are essential to achieve optimal outcome for SBRT with active motion compensation. Local control appears favorable compared to historical control. Long-term LC of the treated lesions was associated with longer overall survival., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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35. Radiomics for liver tumours.
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Dreher C, Linde P, Boda-Heggemann J, and Baessler B
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- Aftercare, Chemoembolization, Therapeutic, Combined Modality Therapy, Deep Learning, Humans, Liver Neoplasms secondary, Liver Neoplasms therapy, Organs at Risk, Prognosis, Radiosurgery, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted methods, Radiotherapy, Image-Guided, Surgery, Computer-Assisted, Computational Biology, Image Processing, Computer-Assisted methods, Liver Neoplasms diagnostic imaging, Radiation Oncology methods
- Abstract
Current research, especially in oncology, increasingly focuses on the integration of quantitative, multiparametric and functional imaging data. In this fast-growing field of research, radiomics may allow for a more sophisticated analysis of imaging data, far beyond the qualitative evaluation of visible tissue changes. Through use of quantitative imaging data, more tailored and tumour-specific diagnostic work-up and individualized treatment concepts may be applied for oncologic patients in the future. This is of special importance in cross-sectional disciplines such as radiology and radiation oncology, with already high and still further increasing use of imaging data in daily clinical practice. Liver targets are generally treated with stereotactic body radiotherapy (SBRT), allowing for local dose escalation while preserving surrounding normal tissue. With the introduction of online target surveillance with implanted markers, 3D-ultrasound on conventional linacs and hybrid magnetic resonance imaging (MRI)-linear accelerators, individualized adaptive radiotherapy is heading towards realization. The use of big data such as radiomics and the integration of artificial intelligence techniques have the potential to further improve image-based treatment planning and structured follow-up, with outcome/toxicity prediction and immediate detection of (oligo)progression. The scope of current research in this innovative field is to identify and critically discuss possible application forms of radiomics, which is why this review tries to summarize current knowledge about interdisciplinary integration of radiomics in oncologic patients, with a focus on investigations of radiotherapy in patients with liver cancer or oligometastases including multiparametric, quantitative data into (radio)-oncologic workflow from disease diagnosis, treatment planning, delivery and patient follow-up.
- Published
- 2020
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36. Advanced Diffusion-Weighted Abdominal Imaging: Qualitative and Quantitative Comparison of High and Ultra-High b-Values for Lesion Detection and Image Quality.
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Dreher C, Kuder TA, König F, Paech D, Tavakoli A, Laun FB, Flothow F, Gnirs R, Benkert T, Strecker R, Schlemmer HP, and Bickelhaupt S
- Subjects
- Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Phantoms, Imaging, Prospective Studies, Reproducibility of Results, Young Adult, Abdomen diagnostic imaging, Abdominal Neoplasms diagnosis, Diffusion Magnetic Resonance Imaging methods
- Abstract
Introduction: Magnetic resonance imaging (MRI) of the abdomen increasingly incorporates diffusion-weighted imaging (DWI) sequences. Whereas DWI can substantially aid in detecting and characterizing suspicious findings, it remains unclear to what extent the use of ultra-high b-value DWI might further be of aid for the radiologist especially when using DWI sequences with advanced processing. The target of this study was therefore to compare high and ultra-high b-value DWI in abdominal MRI examinations., Methods: This institutional review board-approved, prospective study included abdominal MRI examinations of 70 oncologic patients (mean age, 58 years; range, 21-90 years) examined with a clinical 1.5 T MRI scanner (MAGNETOM Aera, Siemens Healthcare, Erlangen, Germany) with an advanced echo planar DWI sequence (b = 0, 50, 900, and 1500 s/mm) after ex vivo phantom and in vivo volunteer investigations. High b900 and ultra-high b1500 DWIs were compared by a qualitative reading for image quality and lesion conspicuity using a 5-point Likert scale with 2 radiologists as readers. The ratios of apparent signal intensities of suspicious lesions/normal tissue of the same organ (LNTRs) were calculated. Appropriate methods were used for statistical analysis, including Wilcoxon signed-rank test and κ statistic for interreader agreement analysis (P < 0.05/0.0125/0.005 after Bonferroni correction)., Results: Image quality was significantly increased with b900 as compared with b1500 DWI (P < 0.001) despite using an advanced DWI sequence. A total of 153 suspicious lesions were analyzed. Overall reader confidence for characterization/detection of malignant lesions and, correspondingly, the LNTR (mean, 2.7 ± 1.8 vs 2.4 ± 1.6) were significantly higher with b900 than with b1500 DWI (P < 0.001 and P < 0.001). The increased confidence of lesion recognition and LNTR in the b900 DWI remained significant qualitatively in lymphatic and hepatic lesions and quantitatively in lymphatic, pulmonal, and osseous lesions., Conclusions: Using high b-value DWI (900 s/mm) provided an improved image quality and also lesion conspicuity as compared with ultra-high b-value DWI (1500 s/mm) in oncologic abdominal examinations despite using advanced processing. Consequently, the value for additional ultra-high b-value DWI in oncologic examinations should be critically evaluated in future studies.
- Published
- 2020
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37. Modulating Diffusion-Weighted Magnetic Resonance Imaging for Screening in Oncologic Tertiary Prevention: A Prospective Ex Vivo and In Vivo Study.
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Dreher C, Kuder TA, König F, Paech D, Tavakoli A, Laun FB, Flothow F, Gnirs R, Benkert T, Nickel D, Strecker R, Schlemmer HP, and Bickelhaupt S
- Subjects
- Adult, Aged, Aged, 80 and over, Artifacts, Female, Humans, Male, Middle Aged, Motion, Phantoms, Imaging, Prospective Studies, Reproducibility of Results, Signal-To-Noise Ratio, Young Adult, Abdominal Neoplasms diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Image Interpretation, Computer-Assisted methods, Tertiary Prevention methods
- Abstract
Introduction: Diffusion-weighted imaging (DWI) is an important part of oncological magnetic resonance imaging (MRI) examinations, especially for tertiary cancer prevention in terms of early detection of recurrent disease. However, abdominal studies can be challenged by motion artifacts, poor signal-to-noise ratios, and visibility of retroperitoneal structures, which necessitates sequence optimization depending on the investigated region. This study aims at prospectively evaluating an adapted DWI sequence ex vivo and in vivo in oncologic patients undergoing abdominal MRI., Methods: This institutional review board-approved, prospective study included phantom measurements, volunteer examinations, and oncologic patient examinations of the abdomen. Fifty-seven MRI examinations in 54 patients (mean age, 58 years; range, 21-90 years) were included into the analysis. The MRI examination were performed at a 1.5 T MRI scanner (MAGNETOM Aera; Siemens Healthcare, Erlangen, Germany) and included both a standard EPI-DWI (s-DWI; b = 50, 900 s/mm) and an adapted DWI (opt-DWI; EPI-DWI with b = 0, 50, 900, 1500 s/mm, acquisition with higher spatial resolution and optimized processing for the abdomen including motion correction, adaptive image combination, and background suppression). For b = 900 s/mm, the ratio of signal intensity in the normal tissue and the standard deviation of the noise in the surrounding air was quantitatively calculated; image quality and tissue differentiation parameters were rated by 2 independent, blinded readers using a 5-point Likert scale. Statistics included Wilcoxon signed-rank test and kappa statistic (P < 0.05/0.0125 after Bonferroni correction)., Results: The DWI phantom demonstrated an optimized contour sharpness and inlay differentiation for opt-DWI. The apparent ratio of normal tissue signal/standard deviation of background noise at b = 900 s/mm of the right/left hemiabdomen was significantly increased in opt-DWI (mean, 71.9 ± 23.5/86.0 ± 43.3) versus s-DWI (mean, 51.4 ± 15.4/63.4 ± 36.5; P < 0.001). Image quality parameters (contour sharpness and tissue differentiation of upper abdominal and retroperitoneal structures) were significantly increased in opt-DWI versus s-DWI (P < 0.001). Interreader reliability test showed good agreement (kappa = 0.768; P < 0.001)., Discussion: This study prospectively evaluated the potential of adapted DWI for screening in tertiary prevention of oncologic patients. An optimized DWI protocol with advanced processing achieved improved image quality in quantitative and qualitative analyses. Oncological optimization of DWI should be performed before its application in cancer patients to improve both screening and follow-up examinations, to better unleash the diagnostic potential of DWI.
- Published
- 2019
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38. Relaxation-compensated amide proton transfer (APT) MRI signal intensity is associated with survival and progression in high-grade glioma patients.
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Paech D, Dreher C, Regnery S, Meissner JE, Goerke S, Windschuh J, Oberhollenzer J, Schultheiss M, Deike-Hofmann K, Bickelhaupt S, Radbruch A, Zaiss M, Unterberg A, Wick W, Bendszus M, Bachert P, Ladd ME, and Schlemmer HP
- Subjects
- Adult, Aged, Amides, Brain Neoplasms enzymology, Brain Neoplasms pathology, Disease Progression, Female, Glioblastoma diagnostic imaging, Glioblastoma enzymology, Glioblastoma pathology, Glioma enzymology, Glioma pathology, Humans, Isocitrate Dehydrogenase metabolism, Kaplan-Meier Estimate, Male, Middle Aged, Neoplasm Grading, Prognosis, Progression-Free Survival, Prospective Studies, Protons, Brain Neoplasms diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Glioma diagnostic imaging
- Abstract
Objectives: The purpose of this study was to investigate the association of relaxation-compensated chemical exchange saturation transfer (CEST) MRI with overall survival (OS) and progression-free survival (PFS) in newly diagnosed high-grade glioma (HGG) patients., Methods: Twenty-six patients with newly diagnosed high-grade glioma (WHO grades III-IV) were included in this prospective IRB-approved study. CEST MRI was performed on a 7.0-T whole-body scanner. Association of patient OS/PFS with relaxation-compensated CEST MRI (amide proton transfer (APT), relayed nuclear Overhauser effect (rNOE)/NOE, downfield-rNOE-suppressed APT (dns-APT)) and diffusion-weighted imaging (apparent diffusion coefficient) were assessed using the univariate Cox proportional hazards regression model. Hazard ratios (HRs) and corresponding 95% confidence intervals were calculated. Furthermore, OS/PFS association with clinical parameters (age, gender, O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation status, and therapy: biopsy + radio-chemotherapy vs. debulking surgery + radio-chemotherapy) were tested accordingly., Results: Relaxation-compensated APT MRI was significantly correlated with patient OS (HR = 3.15, p = 0.02) and PFS (HR = 1.83, p = 0.009). The strongest association with PFS was found for the dns-APT metric (HR = 2.61, p = 0.002). These results still stand for the relaxation-compensated APT contrasts in a homogenous subcohort of n = 22 glioblastoma patients with isocitrate dehydrogenase (IDH) wild-type status. Among the tested clinical parameters, patient age (HR = 1.1, p = 0.001) and therapy (HR = 3.68, p = 0.026) were significant for OS; age additionally for PFS (HR = 1.04, p = 0.048)., Conclusion: Relaxation-compensated APT MRI signal intensity is associated with overall survival and progression-free survival in newly diagnosed, previously untreated glioma patients and may, therefore, help to customize treatment and response monitoring in the future., Key Points: • Amide proton transfer (APT) MRI signal intensity is associated with overall survival and progression in glioma patients. • Relaxation compensation enhances the information value of APT MRI in tumors. • Chemical exchange saturation transfer (CEST) MRI may serve as a non-invasive biomarker to predict prognosis and customize treatment.
- Published
- 2019
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39. Incidental dose distribution to locoregional lymph nodes of breast cancer patients undergoing adjuvant radiotherapy with tomotherapy - is it time to adjust current contouring guidelines to the radiation technique?
- Author
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Mayinger M, Borm KJ, Dreher C, Dapper H, Duma MN, Oechsner M, Kampfer S, Combs SE, and Habermehl D
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- Breath Holding, Female, Humans, Middle Aged, Prognosis, Radiotherapy Dosage, Radiotherapy, Conformal methods, Radiotherapy, Intensity-Modulated, Retrospective Studies, Breast Neoplasms radiotherapy, Lymph Nodes radiation effects, Organs at Risk radiation effects, Radiation Injuries prevention & control, Radiotherapy Planning, Computer-Assisted methods, Radiotherapy, Adjuvant standards, Radiotherapy, Conformal standards
- Abstract
Purpose/objective(s): Along with breast-conserving surgery (BCS), adjuvant radiotherapy (RT) of patients with early breast cancer plays a crucial role in the oncologic treatment concept. Conventionally, irradiation is carried out with the aid of tangentially arranged fields. However, more modern and more complex radiation techniques such as IMRT (intensity-modulated radio therapy) are used more frequently, as they improve dose conformity and homogeneity and, in some cases, achieve better protection of adjacent risk factors. The use of this technique has implications for the incidental- and thus unintended- irradiation of adjacent loco regional lymph drainage in axillary lymph node levels I-III and internal mammary lymph nodes (IMLNs). A comparison of a homogeneous "real-life" patient collective, treated with helical tomotherapy (TT), patients treated with 3D conformal RT conventional tangentially arranged fields (3DCRT) and deep inspiration breath hold (3DCRT-DIBH), was conducted., Materials/methods: This study included 90 treatment plans after BCS, irradiated in our clinic from January 2012 to August 2016 with TT (n = 30) and 3D-CRT (n = 30), 3DCRT DIBH (n = 30). PTVs were contoured at different time points by different radiation oncologists (> 7). TT was performed with a total dose of 50.4 Gy and a single dose of 1.8 Gy with a simultaneous integrated boost (SIB) to the tumor cavity (TT group). Patients irradiated with 3DCRT/3DCRT DIBH received 50 Gy à 2 Gy and a sequential boost. Contouring of lymph drainage routes was performed retrospectively according to RTOG guidelines., Results: Average doses (DMean) in axillary lymph node Level I/Level II/Level III were 31.6 Gy/8.43 Gy/2.38 Gy for TT, 24.0 Gy/11.2 Gy/3.97 Gy for 3DCRT and 24.7 Gy/13.3 Gy/5.59 Gy for 3DCRT-DIBH patients. Internal mammary lymph nodes (IMLNs) Dmean were 27.8 Gy (TT), 13.5 Gy (3DCRT), and 18.7 Gy (3DCRT-DIBH). Comparing TT to 3DCRT-DIBH dose varied significantly in all axillary lymph node levels and the IMLNs. Comparing TT to 3DCRT significant dose difference in Level I and IMLNs was observed., Conclusion: Dose applied to locoregional lymph drainage pathways varies comparing tomotherapy plans to conventional tangentially arranged fields. Studies are warranted whether dose variations influence loco-regional spread and must have implications for target volume definition guidelines.
- Published
- 2019
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40. Chemical exchange saturation transfer (CEST) signal intensity at 7T MRI of WHO IV° gliomas is dependent on the anatomic location.
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Dreher C, Oberhollenzer J, Meissner JE, Windschuh J, Schuenke P, Regnery S, Sahm F, Bickelhaupt S, Bendszus M, Wick W, Unterberg A, Zaiss M, Bachert P, Ladd ME, Schlemmer HP, Radbruch A, and Paech D
- Subjects
- Adult, Healthy Volunteers, Humans, Magnetic Resonance Imaging, Middle Aged, Prospective Studies, Reproducibility of Results, Young Adult, Brain diagnostic imaging, Brain Neoplasms diagnostic imaging, Diffusion Magnetic Resonance Imaging, Glioblastoma diagnostic imaging, Gliosarcoma diagnostic imaging
- Abstract
Background: Chemical exchange saturation transfer (CEST) is a novel MRI technique applied to brain tumor patients., Purpose: To investigate the anatomic location dependence of CEST MRI obtained at 7T and histopathological/molecular parameters in WHO IV° glioma patients., Study Type: Analytic prospective study., Population: Twenty-one patients with newly diagnosed WHO IV° gliomas were studied prior to surgery; 11 healthy volunteers were investigated., Field Strength/sequence: Conventional MRI (contrast-enhanced, T
2 w and diffusion-weighted imaging) at 3T and T2 w and CEST MRI at 7T was performed for patients and both patients and volunteers., Assessment: Mean CEST signal intensities (nuclear-Overhauser-enhancement [NOE], amide-proton-transfer [APT], downfield NOE-suppressed APT [dns-APT]), ADC values, and histopathological/molecular parameters were evaluated with regard to hemisphere location and contact with the subventricular zone. CEST signal intensities of cerebral tissue of healthy volunteers were evaluated with regard to hemisphere discrimination., Statistical Tests: Spearman correlation, Mann-Whitney U-test, Wilcoxon signed-rank-test, Fisher's exact test, and area under the receiver operating curve., Results: Maximum APT and dns-APT signal intensities were significantly different in right vs. left hemisphere gliomas (P = 0.037 and P = 0.007), but not in right vs. left hemisphere cerebral tissue of healthy subjects (P = 0.062-0.859). Mean ADC values were significantly decreased in right vs. left hemisphere gliomas (P = 0.044). Mean NOE signal intensity did not differ significantly between gliomas of either hemisphere (P = 0.820), but in case of subventricular zone contact (P = 0.047). A significant correlation was observed between APT and dns-APT and ADC signal intensities (rs = -0.627, P = 0.004 and rs = -0.534, P = 0.019), but not between NOE and ADC (rs = -0.341, P = 0.154). Histopathological/molecular parameters were not significantly different concerning the tumor location (P = 0.104-1.000, P = 0.286-0.696)., Data Conclusion: APT, dns-APT, and ADC were inversely correlated and depended on the gliomas' hemisphere location. NOE showed significant dependence on subventricular zone contact. Location dependency of APT- and NOE-mediated CEST effects should be considered in clinical investigations of CEST MRI., Level of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:777-785., (© 2018 International Society for Magnetic Resonance in Medicine.)- Published
- 2019
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41. Abbreviated MRI Protocols in Breast Cancer Diagnostics.
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Deike-Hofmann K, Koenig F, Paech D, Dreher C, Delorme S, Schlemmer HP, and Bickelhaupt S
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- Breast diagnostic imaging, Contrast Media pharmacology, Early Detection of Cancer methods, Female, Humans, Image Processing, Computer-Assisted methods, Multimodal Imaging methods, Breast Neoplasms diagnostic imaging, Magnetic Resonance Imaging methods
- Abstract
Oncologic imaging focused on the detection of breast cancer is of increasing importance, with over 1.7 million new cases detected each year worldwide. MRI of the breast has been described to be one of the most sensitive imaging modalities in breast cancer detection; however, clinical use is limited due to high costs. In the past, the objective and clinical routine of oncologic imaging was to provide one extended imaging protocol covering all potential needs and clinical implications regardless of the specific clinical indication or question. Future protocols might be more focused according to a "keep it short and simple" approach, with a reduction of patient magnet time and a limited number of images to review. Rather than replacing conventional full-diagnostic breast MRI protocols, these approaches aim at introducing a new thinking in oncologic imaging using a diversification of available imaging approaches targeted to the dedicated clinical needs of the individual patient. Here we review current approaches on using abbreviated protocols that aim to increase the clinical availability and use of breast MRI for improved early detection of breast cancer. Level of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:647-658., (© 2018 International Society for Magnetic Resonance in Medicine.)
- Published
- 2019
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42. Assessing the predictability of IDH mutation and MGMT methylation status in glioma patients using relaxation-compensated multipool CEST MRI at 7.0 T.
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Paech D, Windschuh J, Oberhollenzer J, Dreher C, Sahm F, Meissner JE, Goerke S, Schuenke P, Zaiss M, Regnery S, Bickelhaupt S, Bäumer P, Bendszus M, Wick W, Unterberg A, Bachert P, Ladd ME, Schlemmer HP, and Radbruch A
- Subjects
- Adult, Aged, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Female, Follow-Up Studies, Glioma diagnostic imaging, Glioma pathology, Humans, Male, Middle Aged, Neoplasm Grading, Predictive Value of Tests, Prospective Studies, ROC Curve, Brain Neoplasms genetics, DNA Methylation, DNA Modification Methylases genetics, DNA Repair Enzymes genetics, Diffusion Magnetic Resonance Imaging methods, Glioma genetics, Isocitrate Dehydrogenase genetics, Mutation, Tumor Suppressor Proteins genetics
- Abstract
Background: Early identification of prognostic superior characteristics in glioma patients such as isocitrate dehydrogenase (IDH) mutation and O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation status is of great clinical importance. The study purpose was to investigate the non-invasive predictability of IDH mutation status, MGMT promoter methylation, and differentiation of low-grade versus high-grade glioma (LGG vs HGG) in newly diagnosed patients employing relaxation-compensated multipool chemical exchange saturation transfer (CEST) MRI at 7.0 Tesla., Methods: Thirty-one patients with newly diagnosed glioma were included in this prospective study. CEST MRI was performed at a 7T whole-body scanner. Nuclear Overhauser effect (NOE) and isolated amide proton transfer (APT; downfield NOE-suppressed APT = dns-APT) CEST signals (mean value and 90th signal percentile) were quantitatively investigated in the whole tumor area with regard to predictability of IDH mutation, MGMT promoter methylation status, and differentiation of LGG versus HGG. Statistics were performed using receiver operating characteristic (ROC) and area under the curve (AUC) analysis. Results were compared with advanced MRI methods (apparent diffusion coefficient and relative cerebral blood volume ROC/AUC analysis) obtained at 3T., Results: dns-APT CEST yielded highest AUCs in IDH mutation status prediction (dns-APTmean = 91.84%, P < 0.01; dns-APT90 = 97.96%, P < 0.001). Furthermore, dns-APT metrics enabled significant differentiation of LGG versus HGG (AUC: dns-APTmean = 0.78, P < 0.05; dns-APT90 = 0.83, P < 0.05). There was no significant difference regarding MGMT promoter methylation status at any contrast (P > 0.05)., Conclusions: Relaxation-compensated multipool CEST MRI, particularly dns-APT imaging, enabled prediction of IDH mutation status and differentiation of LGG versus HGG and should therefore be considered as a non-invasive MR biomarker in the diagnostic workup.
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- 2018
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43. New Classes of Polycationic Compounds as Preservatives for Ophthalmic Formulations.
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von Deylen D, Dreher C, Seidelmann O, and Reichl S
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- Administration, Ophthalmic, Benzalkonium Compounds administration & dosage, Benzalkonium Compounds chemical synthesis, Benzalkonium Compounds therapeutic use, Cell Line, Drug Compounding, Epithelial Cells drug effects, Humans, Microbial Sensitivity Tests, Polyelectrolytes, Polymers administration & dosage, Polymers chemical synthesis, Polymers therapeutic use, Pseudomonas aeruginosa drug effects, Anti-Infective Agents administration & dosage, Anti-Infective Agents chemistry, Ophthalmic Solutions administration & dosage, Ophthalmic Solutions chemistry, Polyamines, Preservatives, Pharmaceutical administration & dosage, Preservatives, Pharmaceutical chemistry
- Abstract
Purpose: The purpose of this research work was to develop new polycationic compounds based on pyridine and piperidine structures with high antimicrobial activities against bacteria and fungi. Furthermore, the compounds should offer a lower toxicity than the commonly used preservatives for ophthalmic formulations, such as benzalkonium chloride (BAC) and polyquaternium-1 (PQ1)., Methods: Two polymers and three dimeric compounds were developed. Minimum inhibitory concentrations were determined for Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis. The compounds were characterized regarding their impact on cell viability, cytotoxicity, epithelial integrity and surface tension. MTT and CytoTox-Glo™ assays, permeation studies with mannitol and transepithelial electrical resistance (TEER) measurements were performed on human corneal epithelial or MDCK I cells. BAC and PQ1 were used as references., Results: Three polycationic compounds exhibited high antimicrobial activity against the tested microorganisms comparable to that of BAC. Four compounds were tolerated as well as or better than PQ1. In addition, the TEER, permeability and surface tension were only affected by compounds with amphiphilic properties., Conclusion: The pyridine- and piperidine-based polycationic compounds are promising candidates as new preservatives for ophthalmic formulations. Their high antimicrobial efficacy and good tolerability indicate a different mechanism of action compared to BAC.
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- 2018
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44. Chemical exchange saturation transfer MRI serves as predictor of early progression in glioblastoma patients.
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Regnery S, Adeberg S, Dreher C, Oberhollenzer J, Meissner JE, Goerke S, Windschuh J, Deike-Hofmann K, Bickelhaupt S, Zaiss M, Radbruch A, Bendszus M, Wick W, Unterberg A, Rieken S, Debus J, Bachert P, Ladd M, Schlemmer HP, and Paech D
- Abstract
Purpose: To prospectively investigate chemical exchange saturation transfer (CEST) MRI in glioblastoma patients as predictor of early tumor progression after first-line treatment., Experimental Design: Twenty previously untreated glioblastoma patients underwent CEST MRI employing a 7T whole-body scanner. Nuclear Overhauser effect (NOE) as well as amide proton transfer (APT) CEST signals were isolated using Lorentzian difference (LD) analysis and relaxation compensated by the apparent exchange-dependent relaxation rate (AREX) evaluation. Additionally, NOE-weighted asymmetric magnetic transfer ratio (MTRasym) and downfield-NOE-suppressed APT (dns-APT) were calculated. Patient response to consecutive treatment was determined according to the RANO criteria. Mean signal intensities of each contrast in the whole tumor area were compared between early-progressive and stable disease., Results: Pre-treatment tumor signal intensity differed significantly regarding responsiveness to first-line therapy in NOE-LD ( p = 0.0001), NOE-weighted MTRasym ( p = 0.0186) and dns-APT ( p = 0.0328) contrasts. Hence, significant prediction of early progression was possible employing NOE-LD (AUC = 0.98, p = 0.0005), NOE-weighted MTRasym (AUC = 0.83, p = 0.0166) and dns-APT (AUC = 0.80, p = 0.0318). The NOE-LD provided the highest sensitivity (91%) and specificity (100%)., Conclusions: CEST derived contrasts, particularly NOE-weighted imaging and dns-APT, yielded significant predictors of early progression after fist-line therapy in glioblastoma. Therefore, CEST MRI might be considered as non-invasive tool for customization of treatment in the future., Competing Interests: CONFLICTS OF INTEREST The authors declare no potential conflicts of interest.
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- 2018
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45. Prospective feasibility analysis of a novel off-line approach for MR-guided radiotherapy.
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Bostel T, Pfaffenberger A, Delorme S, Dreher C, Echner G, Haering P, Lang C, Splinter M, Laun F, Müller M, Jäkel O, Debus J, Huber PE, Sterzing F, and Nicolay NH
- Subjects
- Adult, Aged, Cone-Beam Computed Tomography, Feasibility Studies, Female, Humans, Male, Middle Aged, Neoplasm Staging, Outcome and Process Assessment, Health Care, Patient Positioning, Pelvic Neoplasms diagnostic imaging, Pelvic Neoplasms pathology, Prospective Studies, Magnetic Resonance Imaging methods, Pelvic Neoplasms radiotherapy, Radiotherapy, Image-Guided methods
- Abstract
Background: The present work aimed to analyze the feasibility of a shuttle-based MRI-guided radiation therapy (MRgRT) in the treatment of pelvic malignancies., Patients and Methods: 20 patients with pelvic malignancies were included in this prospective feasibility analysis. Patients underwent daily MRI in treatment position prior to radiotherapy at the German Cancer Research Center. Positional inaccuracies, time and patient compliance were assessed for the application of off-line MRgRT., Results: In 78% of applied radiation fractions, MR imaging for position verification could be performed without problems. Additionally, treatment-related side effects and reduced patient compliance were only responsible for omission of MRI in 9% of radiation fractions. The study workflow took a median time of 61 min (range 47-99 min); duration for radiotherapy alone was 13 min (range 7-26 min). Patient positioning, MR imaging and CT imaging including patient repositioning and the shuttle transfer required median times of 10 min (range 7-14 min), 26 min (range 15-60 min), 5 min (range 3-8 min) and 8 min (range 2-36 min), respectively. To assess feasibility of shuttle-based MRgRT, the reference point coordinates for the x, y and z axis were determined for the MR images and CT obtained prior to the first treatment fraction and correlated with the coordinates of the planning CT. In our dataset, the median positional difference between MR imaging and CT-based imaging based on fiducial matching between MR and CT imaging was equal to or less than 2 mm in all spatial directions. The limited space in the MR scanner influenced patient selection, as the bore of the scanner had to accommodate the immobilization device and the constructed stereotactic frame. Therefore, obese, extremely muscular or very tall patients could not be included in this trial in addition to patients for whom exposure to MRI was generally judged inappropriate., Conclusion: This trial demonstrated for the first time the feasibility and patient compliance of a shuttle-based off-line approach to MRgRT of pelvic malignancies.
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- 2018
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46. Evaluation of the tumor movement and the reproducibility of two different immobilization setups for image-guided stereotactic body radiotherapy of liver tumors.
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Dreher C, Oechsner M, Mayinger M, Beierl S, Duma MN, Combs SE, and Habermehl D
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- Humans, Movement, Patient Positioning, Reproducibility of Results, Immobilization instrumentation, Liver Neoplasms radiotherapy, Radiosurgery instrumentation, Radiotherapy, Image-Guided instrumentation
- Abstract
Background: The purpose of this study is to evaluate the tumor movement and accuracy of patient immobilization in stereotactic body radiotherapy of liver tumors with low pressure foil or abdominal compression., Methods: Fifty-four liver tumors treated with stereotactic body radiotherapy were included in this study. Forty patients were immobilized by a vacuum couch with low pressure foil, 14 patients by abdominal compression. We evaluated the ratio of gross tumor volume/internal target volume, the tumor movement in 4D-computed tomography scans and daily online adjustments after cone beam computed tomography scans., Results: The ratio of gross tumor volume/internal target volume was smaller with low pressure foil. The tumor movement in 4D-computed tomography scans was smaller with abdominal compression, the cranial movement even significantly different (p = 0.02). The mean online adjustments and their mean absolute values in the vertical, lateral and longitudinal axis were smaller with abdominal compression. The online adjustments were significantly different (p < 0.013), their absolute values in case of the longitudinal axis (p = 0.043). There was no significant difference of the adjustments' 3D vectors., Conclusions: In comparison to low pressure foil, abdominal compression leads to a reduction of the tumor movement. Online adjustments decreased significantly, thus leading to higher accuracy in patient positioning.
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- 2018
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47. Effective radiotherapeutic treatment intensification in patients with pancreatic cancer: higher doses alone, higher RBE or both?
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Dreher C, Habermehl D, Jäkel O, and Combs SE
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- Humans, Pancreatic Neoplasms pathology, Radiotherapy Dosage, Treatment Outcome, Tumor Burden, Heavy Ion Radiotherapy, Pancreatic Neoplasms radiotherapy, Radiotherapy Planning, Computer-Assisted methods, Relative Biological Effectiveness
- Abstract
Pancreatic cancer, especially in case of locally advanced stage has a poor prognosis. Radiotherapy in general can lead to tumor volume reduction, but further improvements, such as ion beam therapy have to be promoted in order to enable dose escalation, which in turn results in better local control rates and downsizing of the tumor itself. Ion beam therapy with its highly promising physical properties is also accompanied by distinct inter- and intrafractional challenges in case of robustness. First clinical results are promising, but further research in motion mitigation and biological treatment planning is necessary, in order to determine the best clinical rationales and conditions of ion beam therapy of pancreatic cancer. This review summarizes the current knowledge and studies on ion beam therapy of pancreatic cancer.
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- 2017
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48. Clinical Rationale and Indications for Particle Therapy.
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Dreher C and Combs SE
- Abstract
Particle therapy is characterized by distinct physical properties leading to a reduction of integral dose compared to photons. While protons have an almost comparable biological effect, carbon ions and other heavier charged particles offer an increased relative biological effectiveness. The potential clinical benefit has been pointed out by several groups. Most likely, for protons, children have the largest margin of benefit since their normal tissue is very sensitive to radiation, and curative treatments lead to extremely long-term survivors having a lot of scope for long-term side effects. Many clinical studies, mostly of a retrospective nature, have shown promising results for various tumor types being treated with proton and heavy ion radiotherapy. Further clinical trials are needed in order to evaluate the opportunities of ion beam therapy and its prognostic influence on the general outcome, and many studies are currently recruiting patients. The aim here is to summarize current knowledge, possible clinical rationales, and indications for ion beam therapy., (© 2018 S. Karger AG, Basel.)
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- 2017
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49. Optimization of Carbon Ion Treatment Plans by Integrating Tissue Specific α/β-Values for Patients with Non-Resectable Pancreatic Cancer.
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Dreher C, Scholz C, Pommer M, Brons S, Prokesch H, Ecker S, Debus J, Jäkel O, Combs SE, and Habermehl D
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- Aged, Female, Humans, Male, Middle Aged, Neoplasm Staging, Pancreatic Neoplasms diagnostic imaging, Pancreatic Neoplasms pathology, Radiotherapy Dosage, Spinal Cord radiation effects, Tomography, X-Ray Computed, Heavy Ion Radiotherapy, Pancreatic Neoplasms radiotherapy, Radiotherapy Planning, Computer-Assisted
- Abstract
Background: The aim of the thesis is to improve treatment plans of carbon ion irradiation by integrating the tissues' specific [Formula: see text]-values for patients with locally advanced pancreatic cancer (LAPC)., Material and Methods: Five patients with LAPC were included in this study. By the use of the treatment planning system Syngo RT Planning (Siemens, Erlangen, Germany) treatment plans with carbon ion beams have been created. Dose calculation was based on [Formula: see text]-values for both organs at risk (OAR) and the tumor. Twenty-five treatment plans and thirty-five forward calculations were created. With reference to the anatomy five field configurations were included. Single Beam Optimization (SBO) and Intensity Modulated Particle Therapy (IMPT) were used for optimization. The plans were analyzed with respect to both dose distributions and individual anatomy. The plans were evaluated using a customized index., Results: With regard to the target, a field setup with one single posterior field achieves the highest score in our index. Field setups made up of three fields achieve good results in OAR sparing. Nevertheless, the field setup with one field is superior in complex topographic conditions. But, allocating an [Formula: see text]-value of 2 Gy to the spinal cord leads to critical high maximum doses in the spinal cord. The evaluation of dose profiles showed significant dose peaks at borders of the [Formula: see text]-gradient, especially in case of a single posterior field., Conclusion: Optimization with specific [Formula: see text]-values allows a more accurate view on dose distribution than previously. A field setup with one single posterior field achieves good results in case of difficult topographic conditions, but leads to high maximum doses to the spinal cord. So, field setups with multiple fields seem to be more adequate in case of LAPC, being surrounded by highly radiosensitive normal tissues., Competing Interests: Christian Scholz is employed by Siemens AG. Mira Pommer is employed by Germany Hottinger Baldwin Messtechnik GmbH. Mr. Scholz and Ms. Pommer worked for the Imaging & Therapy Division in the Healthcare Sector of Siemens AG during the study period. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors. The authors received no specific funding for this work. Siemens AG and Germany Hottinger Baldwin Messtechnik GmbH provided support in the form of salaries for authors [CS] and [MP], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.
- Published
- 2016
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50. Metabolic liver function after stereotactic body radiation therapy for hepatocellular carcinoma.
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Dreher C, Høyer KI, Fode MM, Habermehl D, Combs SE, and Høyer M
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- Adult, Aged, Aged, 80 and over, Alanine Transaminase blood, Alkaline Phosphatase blood, Bilirubin blood, Carcinoma, Hepatocellular mortality, Female, Humans, Kaplan-Meier Estimate, Liver radiation effects, Liver Cirrhosis metabolism, Liver Cirrhosis pathology, Liver Function Tests, Liver Neoplasms mortality, Male, Middle Aged, Radiation Dosage, Radiosurgery methods, Serum Albumin metabolism, Carcinoma, Hepatocellular radiotherapy, Liver metabolism, Liver Neoplasms radiotherapy, Radiosurgery adverse effects
- Abstract
Purpose The time course of changes of the liver function after stereotactic body radiotherapy (SBRT) was analyzed in patients treated for non-resectable hepatocellular carcinoma (HCC). Patients and methods Twenty-six patients with non-resectable HCC treated with SBRT were included in this study. Clinical, biochemical and treatment-related parameters were retrospectively collected. S-albumin, s-bilirubin, s-alkaline phosphatase (AP) and s-alanine transaminase (ALAT) at 0, 3, 6, and 12 months after radiotherapy were analyzed. Results Seventeen and nine patients were Child-Pugh class A and B, respectively. The liver was exposed to relatively high radiation doses with mean doses of 1.9-26 Gy. None of the patients developed classic radiotherapy-induced liver disease (RILD), but two patients developed non-classic RILD. Two patients developed grade 3 ascites and no grade 4-5 toxicities were observed. Six patients declined in Child-Pugh class. The s-albumin decreased significantly from a pretreatment median of 37.4-34.36 g/l at three months after SBRT and stabilized thereafter. S-bilirubin, s-AP and s-ALAT did not change significantly over the study period. Conclusion Despite the fact that patients received high radiation dose to the liver, there was only moderate morbidity related to the treatment. The s-albumin decreases over three months after SBRT reflecting minor to moderate hepatic toxicity. S-albumin should be observed in the follow-up of HCC patients treated with SBRT.
- Published
- 2016
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