@article{NeubauerHassoldWarmuthMetzetal.2014,
  author    = {Neubauer, Henning and Hassold, Nicole and Warmuth-Metz, Monika and Winkler, Beate and Kreissl, Michael C. and Ernestus, Karen and Beer, Meinrad},
  title     = {Hit the mark with diffusion-weighted imaging: metastases of rhabdomyosarcoma to the extraocular eye muscles},
  doi       = {10.1186/1471-2431-14-57},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110106},
  year      = {2014},
  abstract  = {Background Rhabdomyosarcoma is the most frequent malignant intraorbital tumour in paediatric patients. Differentiation of tumour recurrence or metastases from post-therapeutic signal alteration can be challenging, using standard MR imaging techniques. Diffusion-weighted MRI (DWI) is increasingly considered a helpful supplementary imaging tool for differentiation of orbital masses. Case presentation We report on a 15-year-old female adolescent of Caucasian ethnicity who developed isolated bilateral thickening of extraocular eye muscles about two years after successful multimodal treatment of orbital alveolar rhabdomyosarcoma. Intramuscular restricted diffusion was the first diagnostic indicator suggestive of metastatic disease to the eye muscles. DWI subsequently showed signal changes consistent with tumour progression, complete remission under chemoradiotherapy and tumour recurrence. Conclusions Restricted diffusivity is a strong early indicator of malignancy in orbital tumours. DWI can be the key to correct diagnosis in unusual tumour manifestations and can provide additional diagnostic information beyond standard MRI and PET/CT. Diffusion-weighted MRI is useful for monitoring therapy response and for detecting tumour recurrence.},
  language  = {en}
}
@article{NeubauerEvangelistaMorbachetal.2012,
  author    = {Neubauer, Henning and Evangelista, Laura and Morbach, Henner and Girschick, Hermann and Prelog, Martina and K{\"o}stler, Herbert and Hahn, Dietbert and Beer, Meinrad},
  title     = {Diffusion-weighted MRI of bone marrow oedema, soft tissue oedema and synovitis in paediatric patients: feasibility and initial experience},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75521},
  year      = {2012},
  abstract  = {Background: MRI has become the mainstay of diagnostic imaging in paediatric rheumatology for lesion detection, differential diagnosis and therapy surveillance. MR imaging of synovitis, in particular, is indispensable for early diagnosis and follow-up in arthritis patients. We used diffusion-weighted MRI (DWI) as a new imaging modality in comparison to standard MRI sequences to study bone marrow oedema, soft-tissue oedema and synovitis in paediatric patients. Methods: A total of 52 patients (mean age 11 ± 5 years) with bone marrow oedema (n = 31), soft-tissue oedema (n = 20) and synovitis (n = 15) were examined with transversal diffusion-weighted single-shot echoplanar imaging in addition to standard MR sequences (T2W TIRM, T1W pre- and post-contrast). Diffusion-weighted images were used for lesion detection and apparent diffusion coefficient (ADC, unit × 10-3 mm2/s) values were measured with ROI technique on ADC maps. Results: In 50 of 52 patients, DWI delineated the lesion of interest corresponding to pathological signal increase on standard sequences. Mean ADC was 1.60 ± 0.14 (range 1.38 - 1.99) in osseous lesions, 1.72 ± 0.31 (range 1.43 - 2.56) in soft tissue oedema and 2.82 ± 0.24 (range 2.47 - 3.18) for joint effusion (ANOVA p<0.001). No significant difference in mean ADC was seen for inflammatory vs. non-inflammatory lesions. Relative signal intensity of oedema was similar for DWI and T2W TIRM. DWI visualised synovial restricted diffusion with a mean ADC of 2.12 ± 0.45 in 12 of 15 patients with synovitis. Conclusions: Diffusion-weighted MRI reliably visualises osseous and soft tissue oedema, as compared to standard sequences. DWI of synovitis is feasible in large joints and presents a novel approach to contrast-free imaging of synovitis. Whole-body DWI for chronic non-bacterial osteomyelitis should be evaluated in future studies.},
  subject      = {Medizin},
  language  = {en}
}
@article{RufBeerKoestleretal.2019,
  author    = {Ruf, Katharina and Beer, Meinrad and K{\"o}stler, Herbert and Weng, Andreas Max and Neubauer, Henning and Klein, Alexander and Platek, Kathleen and Roth, Kristina and Beneke, Ralph and Hebestreit, Helge},
  title     = {Size-adjusted muscle power and muscle metabolism in patients with cystic fibrosis are equal to healthy controls - a case control study},
  series = {BMC Pulmonary Medicine},
  volume    = {19},
  journal   = {BMC Pulmonary Medicine},
  doi       = {10.1186/s12890-019-1039-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200981},
  pages     = {269},
  year      = {2019},
  abstract  = {Background Skeletal muscle function dysfunction has been reported in patients with cystic fibrosis (CF). Studies so far showed inconclusive data whether reduced exercise capacity is related to intrinsic muscle dysfunction in CF. Methods Twenty patients with CF and 23 age-matched controls completed an incremental cardiopulmonary cycling test. Further, a Wingate anaerobic test to assess muscle power was performed. In addition, all participants completed an incremental knee-extension test with 31P magnetic resonance spectroscopy to assess muscle metabolism (inorganic phosphate (Pi) and phosphocreatinine (PCr) as well as intracellular pH). In the MRI, muscle cross-sectional area of the M. quadriceps (qCSA) was also measured. A subgroup of 15 participants (5 CF, 10 control) additionally completed a continuous high-intensity, high-frequency knee-extension exercise task during 31P magnetic resonance spectroscopy to assess muscle metabolism. Results Patients with CF showed a reduced exercise capacity in the incremental cardiopulmonary cycling test (VO2peak: CF 77.8 ± 16.2\%predicted (36.5 ± 7.4 ml/qCSA/min), control 100.6 ± 18.8\%predicted (49.1 ± 11.4 ml/qCSA/min); p < 0.001), and deficits in anaerobic capacity reflected by the Wingate test (peak power: CF 537 ± 180 W, control 727 ± 186 W; mean power: CF 378 ± 127 W, control 486 ± 126 W; power drop CF 12 ± 5 W, control 8 ± 4 W. all: p < 0.001). In the knee-extension task, patients with CF achieved a significantly lower workload (p < 0.05). However, in a linear model analysing maximal work load of the incremental knee-extension task and results of the Wingate test, respectively, only muscle size and height, but not disease status (CF or not) contributed to explaining variance. In line with this finding, no differences were found in muscle metabolism reflected by intracellular pH and the ratio of Pi/PCr at submaximal stages and peak exercise measured through MRI spectroscopy. Conclusions The lower absolute muscle power in patients with CF compared to controls is exclusively explained by the reduced muscle size in this study. No evidence was found for an intrinsic skeletal muscle dysfunction due to primary alterations of muscle metabolism.},
  language  = {en}
}
@article{GrunzSailerLangetal.2022,
  author    = {Grunz, Jan-Peter and Sailer, Lukas and Lang, Patricia and Sch{\"u}le, Simone and Kunz, Andreas Steven and Beer, Meinrad and Hackenbroch, Carsten},
  title     = {Dual-energy CT in sacral fragility fractures: defining a cut-off Hounsfield unit value for the presence of traumatic bone marrow edema in patients with osteoporosis},
  series = {BMC Musculoskeletal Disorders},
  volume    = {23},
  journal   = {BMC Musculoskeletal Disorders},
  number    = {1},
  doi       = {10.1186/s12891-022-05690-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-301125},
  year      = {2022},
  abstract  = {Background Demographic change entails an increasing incidence of fragility fractures. Dual-energy CT (DECT) with virtual non-calcium (VNCa) reconstructions has been introduced as a promising diagnostic method for evaluating bone microarchitecture and marrow simultaneously. This study aims to define the most accurate cut-off value in Hounsfield units (HU) for discriminating the presence and absence of bone marrow edema (BME) in sacral fragility fractures. Methods Forty-six patients (40 women, 6 men; 79.7 ± 9.2 years) with suspected fragility fractures of the sacrum underwent both DECT (90 kVp / 150 kVp with tin prefiltration) and MRI. Nine regions-of-interest were placed in each sacrum on DECT-VNCa images. The resulting 414 HU measurements were stratified into "edema" (n = 80) and "no edema" groups (n = 334) based on reference BME detection in T2-weighted MRI sequences. Area under the receiver operating characteristic curve was calculated to determine the desired cut-off value and an associated conspicuity range for edema detection. Results The mean density within the "edema" group of measurements (+ 3.1 ± 8.3 HU) was substantially higher compared to the "no edema" group (-51.7 ± 21.8 HU; p < 0.010). Analysis in DECT-VNCa images suggested a cut-off value of -12.9 HU that enabled sensitivity and specificity of 100\% for BME detection compared to MRI. A range of HU values between -14.0 and + 20.0 is considered indicative of BME in the sacrum. Conclusions Quantitative analysis of DECT-VNCa with a cut-off of -12.9 HU allows for excellent diagnostic accuracy in the assessment of sacral fragility fractures with associated BME. A diagnostic "one-stop-shop" approach without additional MRI is feasible.},
  language  = {en}
}