Günther Engel

Dr. Günther Engel

orcid

Research Focus & Metrics

Academic Career Length

35Years (1992-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 June 2019 in Cancer Imaging
Verified
Journal Article
Open access
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LALisa Adams
Lisa Adams
KBKeno Bressem
Keno Bressem
PJPhilipp Sebastian Jurmeister
Philipp Sebastian Jurmeister
UFUte Fahlenkamp
Ute Fahlenkamp
BRBernhard Ralla
Bernhard Ralla
MMMarcus R. Makowski
Marcus R. Makowski
Correct staging and grading of patients with clear cell renal cell carcinoma (cRCC) is of clinical relevance for the prediction of operability and for individualized patient management. As partial or radial resection with postoperative tumor grading currently remain the methods of choice for the classification of cRCC, non-invasive preoperative alternatives to differentiate lower grade from higher grade cRCC would be beneficial. This institutional-review-board approved cross-sectional study included twenty-seven patients (8 women, mean age ± SD, 61.3 ± 14.2) with histopathologically confirmed cRCC, graded according to the International Society of Urological Pathology (ISUP). A native, balanced steady-state free precession T2 mapping sequence (TrueFISP) was performed at 1.5 T. Quantitative T2 values were measured with circular 2D ROIs in the solid tumor portion and also in the normal renal parenchyma (cortex and medulla). To estimate the optimal cut-off T2 value for identifying lower grade cRCC, a Receiver Operating Characteristic Curve (ROC) analysis was performed and sensitivity and specificity were calculated. Students’ t-tests were used to evaluate the differences in mean values for continuous variables, while intergroup differences were tested for significance with two-tailed Mann-Whitney-U tests. There were significant differences between the T2 values for lower grade (ISUP 1–2) and higher grade (ISUP 3–4) cRCC (p < 0.001), with higher T2 values for lower grade cRCC compared to higher grade cRCC. The sensitivity and specificity for the differentiation of lower grade from higher grade tumors were 83.3% (95% CI: 0.59–0.96) and 88.9% (95% CI: 0.52–1.00), respectively, using a threshold value of ≥110 ms. Intraobserver/interobserver agreement for T2 measurements was excellent/substantial. Native T2 mapping based on a balanced steady-state free precession MR sequence might support an image-based distinction between lower and higher grade cRCC in a two-tier-system and could be a helpful addition to multiparametric imaging.

15 October 2018 in European Radiology
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Journal Article
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GEGünther Engel
Günther Engel
YBYvonne Y. Bender
Yvonne Y. Bender
LALisa C. Adams
Lisa C. Adams
SBSarah M. Boker
Sarah M. Boker
UFUte L. Fahlenkamp
Ute L. Fahlenkamp
MMMarcus R. Makowski
Marcus R. Makowski

3 August 2023 in Diagnostics
Verified
Journal Article
Open access
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JEJonathan Ehmig
Jonathan Ehmig
GEGünther Engel
Günther Engel
JLJoachim Lotz
Joachim Lotz
WLWolfgang Lehmann
Wolfgang Lehmann
STShahed Taheri
Shahed Taheri
BPBabak Panahi
Babak Panahi
Osteoarthritis (OA) is a common degenerative joint disease that affects millions of people worldwide. Magnetic resonance imaging (MRI) has emerged as a powerful tool for the evaluation and monitoring of OA due to its ability to visualize soft tissues and bone with high resolution. This review aims to provide an overview of the current state of MRI in OA, with a special focus on the knee, including protocol recommendations for clinical and research settings. Furthermore, new developments in the field of musculoskeletal MRI are highlighted in this review. These include compositional MRI techniques, such as T2 mapping and T1rho imaging, which can provide additional important information about the biochemical composition of cartilage and other joint tissues. In addition, this review discusses semiquantitative joint assessment based on MRI findings, which is a widely used method for evaluating OA severity and progression in the knee. We analyze the most common scoring methods and discuss potential benefits. Techniques to reduce acquisition times and the potential impact of deep learning in MR imaging for OA are also discussed, as these technological advances may impact clinical routine in the future.

20 June 2021 in Diagnostics
Verified
Journal Article
Open access
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UFUte Fahlenkamp
Ute Fahlenkamp
JKJan Kunkel
Jan Kunkel
KZKatharina Ziegeler
Katharina Ziegeler
KNKonrad Neumann
Konrad Neumann
LALisa Adams
Lisa Adams
MMMarcus Richard Makowski
Marcus Richard Makowski
MR relaxometry increasingly contributes to liver imaging. Studies on native relaxation times mainly describe relation to the presence of fibrosis. The hypothesis was that relaxation times are also influenced by other inherent factors, including changes in liver synthesis function. With the approval of the local ethics committee and written informed consent, data from 94 patients referred for liver MR imaging, of which 20 patients had cirrhosis, were included. Additionally to standard sequences, both native T1 and T2 parametric maps and T1 maps in the hepatobiliary phase of gadoxetate disodium were acquired. Associations with laboratory variables were assessed. Altogether, there was a negative correlation between albumin and all acquired relaxation times in cirrhotic patients. In non-cirrhotic patients, only T1 values exhibited a negative correlation with albumin. In all patients, bilirubin correlated significantly with post-contrast T1 relaxation times, whereas native relaxation times correlated only in cirrhotic patients. Evaluating patients with pathological INR values, post-contrast relaxation times were significantly higher, whereas native relaxation times did not correlate. In conclusion, apart from confirming the value of hepatobiliary phase T1 mapping, our results show a correlation of native T1 with serum albumin even in non-cirrhotic liver parenchyma, suggesting a direct influence of liver’s synthesis capacity on T1 relaxation times.

1 August 2018 in Clinical Radiology
Verified
Journal Article
Closed access
LALisa Adams
Lisa Adams
BRBernhard Ralla
Bernhard Ralla
GEGünther Engel
Günther Engel
GDG. Diederichs
G. Diederichs
BHB. Hamm
B. Hamm
MMM.R. Makowski
M.R. Makowski

1 January 1992 in Zeitschrift für Kristallographie
Verified
Journal Article
Closed access
GEGünther Engel
Günther Engel
KFK. Fütterer
K. Fütterer
GMG. Mattern
G. Mattern