T Dirrichs
RWTH Aachen University
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Featured researches published by T Dirrichs.
Investigative Radiology | 2014
Sebastian Keil; Alexandra Barabasch; T Dirrichs; Philipp Bruners; Nienke Lynn Hansen; Heribert Bieling; Tim H. Brümmendorf; Christiane K. Kuhl
PurposeWe conducted a systematic analysis of factors (manual vs automated and unidimensional vs 3-dimensional size assessment, and impact of different target lesion selection) contributing to variability of response categorization in the Response Evaluation Criteria for Solid Tumors 1.1. Patients and MethodsA total of 41 female patients (58.1 ± 13.2 years old) with metastatic breast cancer underwent contrast-enhanced thoracoabdominal computed tomography for initial staging and first follow-up after systemic chemotherapy. Data were independently interpreted by 3 radiologists with 5 to 9 years of experience. In addition, response was evaluated by a computer-assisted diagnosis system that allowed automated unidimensional and 3-dimensional assessment of target lesions. ResultsOverall, between-reader agreement was moderate (&kgr; = 0.53), with diverging response classification observed in 19 of 41 patients (46%). In 25 patients, readers had chosen the same, and in 16, readers had chosen different target lesions. Selection of the same target lesions was associated with a 76% rate of agreement (19/25) with regard to response classification; selection of different target lesions was associated with an 81% rate of disagreement (13/16) (P < 0.001). After dichotomizing response classes according to their therapeutic implication in progressive versus nonprogressive, disagreement was observed in 11 of 41 patients (27%) (&kgr; = 0.57). In 9 of these 11 patients, readers had chosen different target lesions. Disagreement rates due to manual versus automated or unidimensional versus volumetric size measurements were less important (11/41 and 6/41; 27% and 15%, respectively). ConclusionsA major source of variability is not the manual or unidimensional measurement, but the variable choice of target lesions between readers. Computer-assisted diagnosis–based analysis or tumor volumetry can help avoid variability due to manual or unidimensional measurements only but will not solve the problem of target lesion selection.
Investigative Radiology | 2016
Simone Schrading; Kevin Strobel; Annika Keulers; T Dirrichs; Christiane K. Kuhl
Objective Magnetic resonance (MR)-guided vacuum-biopsy is technically demanding and may fail depending on target-lesion size or breast size, and location of lesions within the breast. We developed an MR-guided vacuum-assisted biopsy protocol that collects larger amounts of tissue, aiming at an at least partial or complete ablation of the target-lesion, just as it is intended during surgical (excisional) biopsy. Rationale is to avoid biopsy failures (false-negative results due to undersampling) by collecting larger amounts of tissue. We report on our experience with MR-guided vacuum-assisted large-volume breast biopsy (VALB) (MR-guided VALB) with regard to clinical success and complication rates. Materials Institutional review board–approved analysis of 865 patients with 1414 MR imaging (MRI)-only breast lesions who underwent tissue sampling under MRI guidance. Magnetic resonance–guided VALB was performed on a 1.5 T-system with a 9G system. Per target lesion, we collected at least 24 samples, with the biopsy notch directed toward the position of the target until on postbiopsy control imaging the target lesion appeared completely or at least greatly removed. The standard-of-reference was established by at least 24-months follow-up (for benign biopsy results), or results of surgical histology (for malignant or borderline results). We investigated the technical success rates as a function of factors that usually interfere with MR-guided vacuum biopsy. Results Target lesions were located in the central versus peripheral parts of the breast in 66.6% (941/1414) versus 33.6% (473/1414), occurred in large, intermediate, or small breasts in 22.7% (321/1414), 56.4% (797/1414), or 20.9% (296/1414), corresponded to nonmass enhancement (NME) versus mass enhancement (ME) in 64.0% (905/1414) vs. 36.0% (509/1414), with an average size of 23 mm for NME versus 9 mm for ME, respectively. Primary technical failures, that is, inability to reach the target lesion occurred in 0.2% of patients (2/865) and 0.1% of target lesions (2/1414). Successful biopsy, that is, an MR-guided VALB diagnosis matching with the standard of reference, was achieved in 99.5% (859/863) of patients and 99.7% (1408/1412) target lesions that had been amenable to MR-guided VALB. In 0.5% of patients (4/863) and 0.3% of target lesions (4/1412), a radiologic-pathologic mismatch suggested a false-negative biopsy, confirmed by secondary excisional biopsy. The likelihood of failure was independent of the lesions location in the breast, breast size, target lesion size, or target lesion type (NME vs ME). None of the patients with benign MR-guided VALB diagnoses developed breast cancer at the biopsy site during follow-up of 2 years. None of the patients developed major complications. Conclusion Magnetic resonance–guided VALB is a safe procedure that is associated with a high success rate (99.7%) that is independent of the size, type, or location of a target lesion, or the size of the breast, and is associated with a very low complication rate.
Muscles, ligaments and tendons journal | 2017
Matthias Gatz; Björn Rath; M. Tingart; V. Quack; T Dirrichs; Simone Schrading; M. Betsch; Christiane K. Kuhl
BACKGROUND Highly operator-based injection therapy with vasosclerosing and anesthetic polidocanol is used for tendinopathies. This pilot-study evaluates the topical application of polidocanol gel. METHODS Prospective case series. 39 patients with tendinopathies (14 Achilles, 14 patella, 11 wrist extensors) with a symptom duration > 6 months were included. Polidocanol and static stretching were the therapy in the first 2 weeks, while static stretching was continuously performed for 6 months. Clinical outcome was evaluated with VISA-A, VISA-P and DASH Scores and sonographically with B-Mode (B-Mode), Power Doppler (PD) and Shearwave Elastography (SWE). RESULTS 22 patients clinically improved (>+10 score points), 11 patients were without improvement (<+ 10) and 1 patient worsened during 6 months. The VISA-A Score increased in average 19 points from 56 to 75 (p< 0.01), VISA-P Score increased 13 points from 59 to 72 (p< 0,01) and the DASH-Score decreased 20 points from 40 to 20 (p< 0,01). SWE correlates better than B-Mode or PD with symptom improvement. CONCLUSION The combination of static training and topical polidocanol application seems to be successful in the treatment of tendinopathies. Further RCT studies need to evaluate the efficiency of topical polidocanol application. SWE is a more sensitive tool to describe symptom development than PD or B-Mode. LEVEL OF EVIDENCE IV.
Radiology | 2015
Simone Schrading; Martina Distelmaier; T Dirrichs; Sabine Detering; Liv Brolund; Kevin Strobel; Christiane K. Kuhl
Academic Radiology | 2016
T Dirrichs; V. Quack; Matthias Gatz; M. Tingart; Christiane K. Kuhl; Simone Schrading
Academic Radiology | 2015
T Dirrichs; Tobias Penzkofer; Sebastian Reinartz; Thomas Kraus; Andreas H. Mahnken; Christiane K. Kuhl
Journal of Nephrology | 2016
Xoana Barros; T Dirrichs; Ralf Koos; Sebastian Reinartz; Nadine Kaesler; Rafael Kramann; Ulrich Gladziwa; Markus Ketteler; Jürgen Floege; Nikolaus Marx; José Vicente Torregrosa; Andras Keszei; Vincent Brandenburg
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren | 2017
Simone Schrading; Annika Keulers; T Dirrichs; Kevin Strobel; Christiane K. Kuhl
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren | 2017
Simone Schrading; T Dirrichs; Hannah Schneider; Christiane K. Kuhl
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren | 2017
Simone Schrading; Annika Keulers; T Dirrichs; J Arnemann; Christiane K. Kuhl