7 Tesla MRI – Novel Imaging Biomarkers (Paech)
- Research Focus
- Dynamic Glucose-Enhanced (DGE) MRI: Prospective Investigation in Glioblastoma Patients
- Chemical Exchange Saturation Transfer (CEST) Imaging at 7 Tesla (7T) in Glioma Patients
- Mapping Brain Metabolism Using Dynamic O17 MRI at 7 Tesla in Healthy Volunteers and Glioblastoma Patients
- Monitoring Early Treatment Response Effects of Brain Cancer Patients in the Course of Radiotherapy Employing Longitudinal CEST and Sodium MR Imaging at 7T
- CEST Imaging in Breast and Prostate Cancer at 7 Tesla and Clinical Field Strength (3T)
Research Focus
The 7 Tesla (7T) oncologic imaging group at the German Cancer Research Center (DKFZ) focusses on the investigation and clinical translation of molecular MRI contrasts at ultra-high field strength. The goal is to further characterize tumor biology and to assess tumor response in clinical trials employing novel imaging biomarkers sensitive to cellular and microenvironmental information. The research group consists of an interdisciplinary team of scientists from the department of Radiology (E010) and the department of Medical Physics in Radiology (E020). Several projects are ongoing.
Dynamic Glucose-Enhanced (DGE) MRI: Prospective Investigation in Glioblastoma Patients
Contact: Paech/ Görke/ Boyd
DGE MRI uses natural unlabeled glucose as biodegradable MR contrast agent. The aim of this work is to evaluate the contrast's potential to detect intracerebral regions of increased glucose uptake and potentially tumor metabolism following intravenous glucose administration. We could show that a dynamic glucose-enhanced contrast can be obtained that enables the identification of increased glucose uptake in gray matter structures of the brain and the delineation of pathophysiologically altered glucose uptake in glioblastoma, both with high temporal resolution. DGE MRI may allow glucose-enhanced imaging without the limitations of ionizing radiation and the expenses of radioisotopes.
This work is funded by the German Research Foundation (DFG) as part of the research grant " D. PAECH: Chemical exchange sensitive MRI as biomarker of early therapeutic response in glioma patients".
Chemical Exchange Saturation Transfer (CEST) Imaging at 7 Tesla (7T) in Glioma Patients
Contact: Paech/ Schlemmer
CEST imaging is a non-invasive novel molecular MRI technique sensitive to endogenous proteins and their tissue specific concentration. Amide Proton Transfer (APT) and Nuclear Overhauser Enhancement (NOE) mediated CEST imaging are the most commonly used CEST-contrast. We could show that CEST MRI at 7T provides additional information on tumor heterogeneity and displays increased signal intensities beyond the borders of blood brain barrier disruption that may be linked to tumor infiltration. In ongoing research studies possible clinical applications such as therapy assessment or biopsy planning are investigated. Particularly, the response of brain tumors to radiation therapy is assessed in prospective clinical trials employing CEST MRI.
This work is funded by the German Research Foundation (DFG) as part of the research grant " D. PAECH: Chemical exchange sensitive MRI as biomarker of early therapeutic response in glioma patients".
Mapping Brain Metabolism Using Dynamic O17 MRI at 7 Tesla in Healthy Volunteers and Glioblastoma Patients
Contact: Paech/ Platt
Dynamic 17O MRI utilizes the MR detectable oxygen isotope (17O) to determine functional dynamics in the human brain. The energy metabolism of the human brain (cerebral metabolic rate of oxygen consumption (CMRO2)) is an indicator of cell viability. In many diseases such as cancer (‘Warburg effect’), Parkinson’s or in Alzheimer’s disease CMRO2 is reduced and might therefore be an important diagnostic parameter. In 2012, the world wide first glioblastoma patient successfully underwent 17O MRI at 7 Tesla at the German Cancer Research Center. The method, which includes inhalation of 17O2 gas, was subsequently validated in a volunteer cohort study. In ongoing studies, we investigate the 17O contrast in brain tumor patients, in order to evaluate the method's potential as metabolic imaging technique in clinical cohorts.
Monitoring Early Treatment Response Effects of Brain Cancer Patients in the Course of Radiotherapy Employing Longitudinal CEST and Sodium MR Imaging at 7T
Contact: Paech/ Adeberg / Regnery
Sodium (23Na) MR imaging can be used to assess the tissue sodium concentration (TSC) in human brain parenchyma and tumors. The aim of this work is the evaluation of variations in the TSC for brain tumor patients in the course of radiation therapy, both in the tumor region and surrounded tissue to monitor treatment effects. TSC is linked to the viability of cells in the observed tissue and could therefore give insights into early treatment response effects.
Furthermore, novel imaging biomarkers such as CEST MRI are investigated in radiotherapy patients in order to evaluate how these advanced imaging methods could contribute to clinical decision making.
CEST Imaging in Breast and Prostate Cancer at 7 Tesla and Clinical Field Strength (3T)
Contact: Paech/ Bickelhaupt/ Bonekamp
CEST MRI yields physiological information about protein concentration and pH of living tissue and therefore provides a new MR imaging (MRI) contrast which may highlight active tumor regions. Moreover, it may help to monitor tumor progression and guide treatment of cancer patients. Since CEST uses endogenous metabolite protons, this information is obtained without the need of contrast agents.
In our work, we evaluate the potential of CEST imaging at 7T for breast and prostate lesion detection and characterization. Ultimately, the research group is working on the translation of these novel MRI contrasts to clinical scanners (at 3T field strength) into benefit for patients in daily clinical practice.
Selected Publications
Paech D, Nagel AM, Schultheiss M, et al. Quantitative dynamic oxygen 17 MRI at 7.0 T for the cerebral oxygen metabolism in glioma. (2020) Radiology 295.1 (2020): 181-189. doi.org/10.1148/radiol.2020191711
Loi L, Zimmermann, F, [...], and Paech D. Relaxation-compensated CEST (chemical exchange saturation transfer) imaging in breast cancer diagnostics at 7T. (2020) European Journal of Radiology. May 24;129:109068. doi.org/10.1016/j.ejrad.2020.109068
Paech D, Dreher C, Regnery S, et al. Relaxation-compensated amide proton transfer (APT) MRI signal intensity is associated with survival and progression in high-grade glioma patients. (2019) European Radiology DOI:10.1007/s00330-019-06066-2:
Paech D, Windschuh J, Oberhollenzer J, et al. Assessing the predictability of IDH mutation and MGMT methylation status in glioma patients using relaxation-compensated multi-pool CEST MRI at 7.0 Tesla. (2018) Neuro-Oncology 20:1661-1671. DOI:10.1093/neuonc/noy073.
Regnery S, Adeberg S, [...], and Paech D. Chemical exchange saturation transfer MRI serves as predictor of early progression in glioblastoma patients. (2018) Oncotarget 9(47), 28772.
Paech D, Schuenke P, Koehler C, et al. T1ρ -weighted dynamic glucose enhanced MRI in the human brain. (2017) Radiology 285(3):914-922. DOI:10.1148/radiol.2017162351.
Links
Contact:
Dr. med. Dipl.-Phys. Daniel Paech
https://www.dkfz.de/de/radiologie/mitarbeiterfotos/CV_Paech.pdf
Daniel C Paech (@PaechDC) | Twitter
Funding:
D. Paech is funded by the German Research Foundation (DFG).
Publications:
https://www.ncbi.nlm.nih.gov/pubmed/?term=paech+d
Dynamic glucose-enhance MRI in the media (selected):
- Glucose-MRI technique at 7T aids tumor evaluation (AuntMinnie.com) https://www.auntminnie.com/index.aspx?sec=ser&sub=def&pag=dis&ItemID=117696
- MRI without contrast agents? Yes, with sugar (ScienceDaily) https://www.sciencedaily.com/releases/2017/06/170623110548.htm
- Zuckerlösung statt Kontrastmittel (ÄrzteZeitung) https://www.aerztezeitung.de/medizin/krankheiten/krebs/article/938501/mrt-zuckerloesung-statt-kontrastmittel.html
Oxygen-17 MRI at 7 Tesla in the media (selected):
- A direct window into brain metabolism, Editorial by O. Rapalino (Harvard Medical School): https://pubs.rsna.org/doi/10.1148/radiol.2020192820
- Using oxygen to make cancer visible (Federal Ministry of Education and Research): http://www.research-in-germany.org/news/2020/2/2020-02-19_Using_oxygen_to_make_cancer_visible.html and https://www.dkfz.de/en/presse/pressemitteilungen/2020/dkfz-pm-20-08-Using-oxygen-to-make-cancer-visible.php
- Oxygen provides insights into tumour metabolism (healthcare-in-europe.com): https://healthcare-in-europe.com/en/news/oxygen-makes-cancer-visible-in-mri.htm