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51. Metabolic patterns on [18F]FDG PET/CT in patients with unresectable stage III NSCLC undergoing chemoradiotherapy ± durvalumab maintenance treatment

Author

Holzgreve, Adrien, Taugner, Julian, Käsmann, Lukas, Müller, Philipp, Tufman, Amanda, Reinmuth, Niels, Li, Minglun, Winkelmann, Michael, Unterrainer, Lena M., Nieto, Alexander E., Bartenstein, Peter, Kunz, Wolfgang G., Ricke, Jens, Belka, Claus, Eze, Chukwuka, Unterrainer, Marcus, and Manapov, Farkhad

Published
2023
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52. Development of PSMA-PET-guided CT-based radiomic signature to predict biochemical recurrence after salvage radiotherapy

Author

Spohn, Simon K. B., Schmidt-Hegemann, Nina-Sophie, Ruf, Juri, Mix, Michael, Benndorf, Matthias, Bamberg, Fabian, Makowski, Marcus R., Kirste, Simon, Rühle, Alexander, Nouvel, Jerome, Sprave, Tanja, Vogel, Marco M. E., Galitsnaya, Polina, Gschwend, Jürgen E., Gratzke, Christian, Stief, Christian, Löck, Steffen, Zwanenburg, Alex, Trapp, Christian, Bernhardt, Denise, Nekolla, Stephan G., Li, Minglun, Belka, Claus, Combs, Stephanie E., Eiber, Matthias, Unterrainer, Lena, Unterrainer, Marcus, Bartenstein, Peter, Grosu, Anca-L., Zamboglou, Constantinos, and Peeken, Jan C.

Published
2023
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53. PSMA-PET/CT-guided salvage radiotherapy in recurrent or persistent prostate cancer and PSA < 0.2 ng/ml

Author

Solomonidou, Nantia, Germanou, Daphnie, Strouthos, Iosif, Karagiannis, Efstratios, Farolfi, Andrea, Koerber, Stefan A., Debus, Juergen, Peeken, Jan C., Vogel, Marco E., Vrachimis, Alexis, Spohn, Simon K. B., Shelan, Mohamed, Aebersold, Daniel, Grosu, Anca-Ligia, Ceci, Francesco, Kroeze, Stephanie G. C., Guckenberger, Matthias, Fanti, Stefano, Belka, Claus, Hruby, George, Scharl, S., Wiegel, Thomas, Bartenstein, Peter, Henkenberens, Christoph, Emmett, Louise, Schmidt-Hegemann, Nina Sophie, Ferentinos, Konstantinos, and Zamboglou, Constantinos

Published
2023
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54. TSPO PET signal using [18F]GE180 is associated with survival in recurrent gliomas

Author

Quach, Stefanie, Holzgreve, Adrien, Kaiser, Lena, Unterrainer, Marcus, Dekorsy, Franziska J., Nelwan, Debie V., Bartos, Laura M., Kirchleitner, Sabrina V., Weller, Jonathan, Weidner, Lorraine, Niyazi, Maximilian, Ruf, Viktoria C., Herms, Jochen, Stöcklein, Sophia, Wetzel, Christian, Riemenschneider, Markus J., v. Baumgarten, Louisa, Thon, Niklas, Brendel, Matthias, Rupprecht, Rainer, Bartenstein, Peter, Tonn, Joerg-Christian, and Albert, Nathalie L.

Published
2023
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55. Feasibility of radiomic feature harmonization for pooling of [18F]FET or [18F]GE-180 PET images of gliomas

Author

Adrian Jun Zounek, Nathalie Lisa Albert, Adrien Holzgreve, Marcus Unterrainer, Julia Brosch-Lenz, Simon Lindner, Andreas Bollenbacher, Guido Boening, Rainer Rupprecht, Matthias Brendel, Louisa von Baumgarten, Joerg-Christian Tonn, Peter Bartenstein, Sibylle Ziegler, and Lena Kaiser

Subjects
Radiomics, Robustness, Data Pooling, FET PET, TSPO PET, Glioma, Medical physics. Medical radiology. Nuclear medicine, R895-920
Abstract

Introduction: Large datasets are required to ensure reliable non-invasive glioma assessment with radiomics-based machine learning methods. This can often only be achieved by pooling images from different centers. Moreover, trained models should perform with high accuracy when applied to data from different centers. In this study, the impact of reconstruction settings and segmentation methods on radiomic features derived from amino acid and TSPO PET images of glioma patients was examined. Additionally, the ability to model and thus reduce feature differences was investigated. Methods: [18F]FET and [18F]GE-180 PET data were acquired from 19 glioma patients. For each acquisition, 10 reconstruction settings and 9 segmentation methods were included to emulate multicentric data. Statistical robustness measures were calculated before and after ComBat harmonization. Differences between features due to setting variations were assessed using Friedman test, coefficient of variation (CV) and inter-rater reliability measures, including intraclass and Spearman’s rank correlation coefficients and Fleiss’ Kappa. Results: According to Friedman analyses, most features (>60%) showed significant differences. Yet, CV and inter-rater reliability measures indicated higher robustness. ComBat resulted in almost complete harmonization (>87%) according to Friedman test and little to no improvement according to CV and inter-rater reliability measures. [18F]GE-180 features were more sensitive to reconstruction settings than [18F]FET features. Conclusions: According to Friedman test, feature distributions could be successfully aligned using ComBat. However, depending on settings, changes in patient ranks were observed for some features and could not be eliminated by harmonization. Thus, for clinical utilization it is recommended to exclude affected features.

Published
2023
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57. Combination of pre-treatment dynamic [18F]FET PET radiomics and conventional clinical parameters for the survival stratification in patients with IDH-wildtype glioblastoma

Author

Li, Zhicong, Holzgreve, Adrien, Unterrainer, Lena M., Ruf, Viktoria C., Quach, Stefanie, Bartos, Laura M., Suchorska, Bogdana, Niyazi, Maximilian, Wenter, Vera, Herms, Jochen, Bartenstein, Peter, Tonn, Joerg-Christian, Unterrainer, Marcus, Albert, Nathalie L., and Kaiser, Lena

Published
2023
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58. Additive value of [18F]PI-2620 perfusion imaging in progressive supranuclear palsy and corticobasal syndrome

Author

Katzdobler, Sabrina, Nitschmann, Alexander, Barthel, Henryk, Bischof, Gerard, Beyer, Leonie, Marek, Ken, Song, Mengmeng, Wagemann, Olivia, Palleis, Carla, Weidinger, Endy, Nack, Anne, Fietzek, Urban, Kurz, Carolin, Häckert, Jan, Stapf, Theresa, Ferschmann, Christian, Scheifele, Maximilian, Eckenweber, Florian, Biechele, Gloria, Franzmeier, Nicolai, Dewenter, Anna, Schönecker, Sonja, Saur, Dorothee, Schroeter, Matthias L., Rumpf, Jost-Julian, Rullmann, Michael, Schildan, Andreas, Patt, Marianne, Stephens, Andrew W., van Eimeren, Thilo, Neumaier, Bernd, Drzezga, Alexander, Danek, Adrian, Classen, Joseph, Bürger, Katharina, Janowitz, Daniel, Rauchmann, Boris-Stephan, Stöcklein, Sophia, Perneczky, Robert, Schöberl, Florian, Zwergal, Andreas, Höglinger, Günter U., Bartenstein, Peter, Villemagne, Victor, Seibyl, John, Sabri, Osama, Levin, Johannes, and Brendel, Matthias

Published
2023
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60. Correction to: Next‑generation PET/CT imaging in meningioma—first clinical experiences using the novel SSTR‑targeting peptide [18F]SiTATE

Author

Unterrainer, Marcus, Kunte, Sophie C., Unterrainer, Lena M., Holzgreve, Adrien, Delker, Astrid, Lindner, Simon, Beyer, Leonie, Brendel, Matthias, Kunz, Wolfgang G., Winkelmann, Michael, Cyran, Clemens C., Ricke, Jens, Jurkschat, Klaus, Wängler, Carmen, Wängler, Björn, Schirrmacher, Ralf, Belka, Claus, Niyazi, Maximilian, Tonn, Joerg‑Christian, Bartenstein, Peter, and Albert, Nathalie L.

Published
2023
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61. The maximum standardized uptake value in patients with recurrent or persistent prostate cancer after radical prostatectomy and PSMA-PET-guided salvage radiotherapy—a multicenter retrospective analysis

Author

Spohn, Simon K. B., Farolfi, Andrea, Schandeler, Sarah, Vogel, Marco M. E., Ruf, Juri, Mix, Michael, Kirste, Simon, Ceci, Francesco, Fanti, Stefano, Lanzafame, Helena, Serani, Francesca, Gratzke, Christian, Sigle, August, Combs, Stephanie E., Bernhardt, Denise, Gschwend, Juergen E., Buchner, Josef A., Trapp, Christian, Belka, Claus, Bartenstein, Peter, Unterrainer, Lena, Unterrainer, Marcus, Eiber, Matthias, Nekolla, Stephan G., Schiller, Kilian, Grosu, Anca L., Schmidt-Hegemann, Nina-Sophie, Zamboglou, Constantinos, and Peeken, Jan C.

Published
2022
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62. Addition of Y-90 radioembolization increases tumor response and local disease control in hepatocellular carcinoma patients receiving sorafenib

Author

Öcal, Osman, Schütte, Kerstin, Zech, Christoph J., Loewe, Christian, van Delden, Otto, Vandecaveye, Vincent, Verslype, Chris, Gebauer, Bernhard, Sengel, Christian, Bargellini, Irene, Iezzi, Roberto, Philipp, Alexander, Berg, Thomas, Klümpen, Heinz J., Benckert, Julia, Pech, Maciej, Gasbarrini, Antonio, Amthauer, Holger, Bartenstein, Peter, Sangro, Bruno, Malfertheiner, Peter, Ricke, Jens, and Seidensticker, Max

Published
2022
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63. Cytokine Signaling in Pediatric Kidney Tumor Cell Lines WT-CLS1, WT-3ab and G-401

Author

Elizaveta Fasler-Kan, Milan Milošević, Sabrina Ruggiero, Nijas Aliu, Dietmar Cholewa, Frank-Martin Häcker, Gabriela Dekany, Andreas Bartenstein, and Steffen M. Berger

Subjects
cytokine, JAK-STAT pathway, Wilms tumor, pediatric kidney tumor, signaling, Biology (General), QH301-705.5, Chemistry, QD1-999
Abstract

Renal tumors comprise ~7% of all malignant pediatric tumors. Approximately 90% of pediatric kidney tumors comprise Wilms tumors, and the remaining 10% include clear cell sarcoma of the kidney, malignant rhabdoid tumor of the kidney, renal cell carcinoma and other rare renal tumors. Over the last 30 years, the role of cytokines and their receptors has been considerably investigated in both cancer progression and anti-cancer therapy. However, more effective immunotherapies require the cytokine profiling of each tumor type and comprehensive understanding of tumor biology. In this study, we aimed to investigate the activation of signaling pathways in response to cytokines in three pediatric kidney tumor cell lines, in WT-CLS1 and WT-3ab cells (both are Wilms tumors), and in G-401 cells (a rhabdoid kidney tumor, formerly classified as Wilms tumor). We observed that interferon-alpha (IFN-α) and interferon-gamma (IFN-γ) very strongly induced the activation of the STAT1 protein, whereas IL-6 and IFN-α activated STAT3 and IL-4 activated STAT6 in all examined tumor cell lines. STAT protein activation was examined by flow cytometry and Western blot using phospho-specific anti-STAT antibodies which recognize only activated (phosphorylated) STAT proteins. Nuclear translocation of phospho-STAT proteins upon activation with specific cytokines was furthermore confirmed by immunofluorescence. Our results also showed that both IFN-α and IFN-γ caused upregulation of major histocompatibility complex (MHC) class I proteins, however, these cytokines did not have any effect on the expression of MHC class II proteins. We also observed that pediatric kidney tumor cell lines exhibit the functional expression of an additional cytokine signaling pathway, the tumor necrosis factor (TNF)-α-mediated activation of nuclear factor kappa B (NF-κB). In summary, our data show that human pediatric renal tumor cell lines are responsive to stimulation with various human cytokines and could be used as in vitro models for profiling cytokine signaling pathways.

Published
2024
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67. Feasibility of [68Ga]Ga-FAPI-46 PET/CT for detection of nodal and hematogenous spread in high-grade urothelial carcinoma

Author

Unterrainer, Lena M., Lindner, Simon, Eismann, Lennert, Casuscelli, Jozefina, Gildehaus, Franz-Josef, Bui, Vinh Ngoc, Albert, Nathalie L., Holzgreve, Adrien, Beyer, Leonie, Todica, Andrei, Brendel, Matthias, Cyran, Clemens C., Karl, Alexander, Stief, Christian G., Ledderose, Stephan T., Unterrainer, Marcus, Bartenstein, Peter, Wenter, Vera, and Kretschmer, Alexander

Published
2022
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68. Non-invasive in vivo imaging of porcine islet xenografts in a preclinical model with [68Ga]Ga-exendin-4

Author

Felix Lindheimer, Magdalena Julia Lindner, Rosel Oos, Mohsen Honarpisheh, Yichen Zhang, Yutian Lei, Lelia Wolf-van Buerck, Franz Josef Gildehaus, Simon Lindner, Peter Bartenstein, Elisabeth Kemter, Eckhard Wolf, Jochen Seissler, and Sibylle Ziegler

Subjects
PET, exendin-4, xenografts, transplantation, autoradiography, Medical physics. Medical radiology. Nuclear medicine, R895-920
Abstract

IntroductionIslet xenotransplantation may be a therapeutic option in type 1 diabetes. Recent advances in generating genetically modified source pigs offer advantages as immune suppressants can potentially be eliminated after the transplantation. Therapy monitoring would greatly benefit from noninvasive methods for assessing the viability of transplanted islets. Peptide-based positron emission tomography (PET) targeting the glucagon-like peptide-1 receptor (GLP1R) expression on beta cells may offer a procedure that can directly be translated from an experimental setting to the clinic. The aim of this study was to establish the labeling of the GLP1R ligand [68Ga]Ga-exendin-4, to demonstrate the feasibility of imaging porcine islet xenografts in vivo and to compare signal quality for three different transplantation sites in a mouse model.Materials and methodsMice with engrafted neonatal porcine islet cell clusters (NPICCs) under the kidney capsule, into the inguinal fold, or the lower hindlimb muscle were studied. After reaching normoglycemia, the mice were injected with [68Ga]Ga-exendin-4 for PET data acquisition. Subsequent autoradiography (AR) was used for comparing ex vivo data with in vivo uptake.ResultsNPICCs in the lower right hindlimb muscle could be detected in vivo and in AR. Due to the high background in the kidney and urinary bladder, islets could not be detected in the PET data at transplantation sites close to these organs, while AR showed a clear signal for the islets in the inguinal fold.DiscussionPET with [68Ga]Ga-exendin-4 detects islets transplanted in the hindlimb muscle tissue of mice, offering the potential of longitudinal monitoring of viable porcine islets. Other sites are not suitable for in vivo imaging owing to high activity accumulation of Exendin-4 in kidney and bladder.

Published
2023
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69. The Traumatic Inoculation Process Affects TSPO Radioligand Uptake in Experimental Orthotopic Glioblastoma

Author

Lukas Gold, Enio Barci, Matthias Brendel, Michael Orth, Jiying Cheng, Sabrina V. Kirchleitner, Laura M. Bartos, Dennis Pötter, Maximilian A. Kirchner, Lena M. Unterrainer, Lena Kaiser, Sibylle Ziegler, Lorraine Weidner, Markus J. Riemenschneider, Marcus Unterrainer, Claus Belka, Joerg-Christian Tonn, Peter Bartenstein, Maximilian Niyazi, Louisa von Baumgarten, Roland E. Kälin, Rainer Glass, Kirsten Lauber, Nathalie L. Albert, and Adrien Holzgreve

Subjects
TSPO PET and autoradiography, glioblastoma, traumatic brain injury (TBI), orthotopic implantation, immunohistochemistry, Biology (General), QH301-705.5
Abstract

Background: The translocator protein (TSPO) has been proven to have great potential as a target for the positron emission tomography (PET) imaging of glioblastoma. However, there is an ongoing debate about the potential various sources of the TSPO PET signal. This work investigates the impact of the inoculation-driven immune response on the PET signal in experimental orthotopic glioblastoma. Methods: Serial [18F]GE-180 and O-(2-[18F]fluoroethyl)-L-tyrosine ([18F]FET) PET scans were performed at day 7/8 and day 14/15 after the inoculation of GL261 mouse glioblastoma cells (n = 24) or saline (sham, n = 6) into the right striatum of immunocompetent C57BL/6 mice. An additional n = 25 sham mice underwent [18F]GE-180 PET and/or autoradiography (ARG) at days 7, 14, 21, 28, 35, 50 and 90 in order to monitor potential reactive processes that were solely related to the inoculation procedure. In vivo imaging results were directly compared to tissue-based analyses including ARG and immunohistochemistry. Results: We found that the inoculation process represents an immunogenic event, which significantly contributes to TSPO radioligand uptake. [18F]GE-180 uptake in GL261-bearing mice surpassed [18F]FET uptake both in the extent and the intensity, e.g., mean target-to-background ratio (TBRmean) in PET at day 7/8: 1.22 for [18F]GE-180 vs. 1.04 for [18F]FET, p < 0.001. Sham mice showed increased [18F]GE-180 uptake at the inoculation channel, which, however, continuously decreased over time (e.g., TBRmean in PET: 1.20 at day 7 vs. 1.09 at day 35, p = 0.04). At the inoculation channel, the percentage of TSPO/IBA1 co-staining decreased, whereas TSPO/GFAP (glial fibrillary acidic protein) co-staining increased over time (p < 0.001). Conclusion: We identify the inoculation-driven immune response to be a relevant contributor to the PET signal and add a new aspect to consider for planning PET imaging studies in orthotopic glioblastoma models.

Published
2024
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71. Risk Factors and Outcomes of Nonmelanoma Skin Cancer in Children and Young Adults

Author

Huang, Jennifer T, Coughlin, Carrie C, Hawryluk, Elena B, Hook, Kristen, Humphrey, Stephen R, Kruse, Lacey, Lawley, Leslie, Al-Sayegh, Hasan, London, Wendy B, Marghoob, Ashfaq, Phung, Thuy L, Pope, Elena, Gerami, Pedram, Schmidt, Birgitta, Robinson, Sarah, Bartenstein, Diana, Bahrani, Eman, Brahmbhatt, Meera, Chen, Lily, Haddock, Ellen, Mansour, Danny, Nguyen, Julie, Raisanen, Tom, Tran, Gary, Travis, Kate, Wolner, Zachary, and Eichenfield, Lawrence F

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Oncology and Carcinogenesis, Cancer, Prevention, Pediatric, Clinical Research, Adolescent, Antifungal Agents, Antineoplastic Agents, Carcinoma, Basal Cell, Carcinoma, Squamous Cell, Case-Control Studies, Child, Child, Preschool, Female, Genetic Predisposition to Disease, Humans, Immunosuppressive Agents, Infant, Male, Radiotherapy, Retrospective Studies, Risk Factors, Skin Neoplasms, United States, Voriconazole, Young Adult, basal cell nevus syndrome, chemotherapy, genodermatosis, iatrogenic, prolonged immunosuppression, radiation therapy, voriconazole, xeroderma pigmentosum, Human Movement and Sports Sciences, Paediatrics and Reproductive Medicine, Pediatrics, Paediatrics
Abstract

ObjectiveTo identify risk factors associated with nonmelanoma skin cancer (NMSC) occurrence and survival in children.Study designThis was a multicenter, retrospective, case-control study of patients 12 months prior to diagnosis and 49% of patients were diagnosed with ≥2 skin cancers. At last follow-up, 5% (6 of 124) of patients with NMSC died. Voriconazole exposure was noted in 7 cases and associated with worse 3-year overall survival (P = .001).ConclusionsNMSC in children and young adults is often associated with a predisposing condition or iatrogenic exposure. High-risk patients should be identified early to provide appropriate counseling and management.

Published
2019

72. 68Ga-EMP-100 PET/CT—a novel ligand for visualizing c-MET expression in metastatic renal cell carcinoma—first in-human biodistribution and imaging results

Author

Mittlmeier, Lena M., Todica, Andrei, Gildehaus, Franz-Josef, Unterrainer, Marcus, Beyer, Leonie, Brendel, Matthias, Albert, Nathalie L., Ledderose, Stephan T., Vettermann, Franziska J., Schott, Melanie, Rodler, Severin, Marcon, Julian, Ilhan, Harun, Cyran, Clemens C., Stief, Christian G., Staehler, Michael, and Bartenstein, Peter

Published
2022
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73. High burden of clonal hematopoiesis in first responders exposed to the World Trade Center disaster

Author

Jasra, Sakshi, Giricz, Orsi, Zeig-Owens, Rachel, Pradhan, Kith, Goldfarb, David G., Barreto-Galvez, Angelica, Silver, Alexander J., Chen, Jiahao, Sahu, Srabani, Gordon-Mitchell, Shanisha, Choudhary, Gaurav S., Aluri, Srinivas, Bhagat, Tushar D., Shastri, Aditi, Bejan, Cosmin A., Stockton, Shannon S., Spaulding, Travis P., Thiruthuvanathan, Victor, Goto, Hiroki, Gerhardt, Jeannine, Haider, Syed Hissam, Veerappan, Arul, Bartenstein, Matthias, Nwankwo, George, Landgren, Ola, Weiden, Michael D., Lekostaj, Jacqueline, Bender, Ryan, Fletcher, Frederick, Greenberger, Lee, Ebert, Benjamin L., Steidl, Ulrich, Will, Britta, Nolan, Anna, Madireddy, Advaitha, Savona, Michael R., Prezant, David J., and Verma, Amit

Published
2022
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83. Dosimetry and optimal scan time of [18F]SiTATE-PET/CT in patients with neuroendocrine tumours

Author

Beyer, Leonie, Gosewisch, Astrid, Lindner, Simon, Völter, Friederike, Mittlmeier, Lena M., Tiling, Reinhold, Brendel, Matthias, Cyran, Clemens C., Unterrainer, Marcus, Rübenthaler, Johannes, Auernhammer, Christoph J., Spitzweg, Christine, Böning, Guido, Gildehaus, F. J., Jurkschat, Klaus, Wängler, Carmen, Wängler, Björn, Schirrmacher, Ralf, Wenter, Vera, Todica, Andrei, Bartenstein, Peter, and Ilhan, Harun

Published
2021
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87. Machine learning-based approach reveals essential features for simplified TSPO PET quantification in ischemic stroke patients.

Author

Zatcepin, Artem, Kopczak, Anna, Holzgreve, Adrien, Hein, Sandra, Schindler, Andreas, Duering, Marco, Kaiser, Lena, Lindner, Simon, Schidlowski, Martin, Bartenstein, Peter, Albert, Nathalie, Brendel, Matthias, and Ziegler, Sibylle I.

Abstract

Neuroinflammation evaluation after acute ischemic stroke is a promising option for selecting an appropriate post-stroke treatment strategy. To assess neuroinflammation in vivo , translocator protein PET (TSPO PET) can be used. However, the gold standard TSPO PET quantification method includes a 90 min scan and continuous arterial blood sampling, which is challenging to perform on a routine basis. In this work, we determine what information is required for a simplified quantification approach using a machine learning algorithm. We analyzed data from 18 patients with ischemic stroke who received 0–90 min [18F]GE-180 PET as well as T1-weigted (T1w), FLAIR, and arterial spin labeling (ASL) MRI scans. During PET scans, five manual venous blood samples at 5, 15, 30, 60, and 85 min post injection (p.i.) were drawn, and plasma activity concentration was measured. Total distribution volume (V T) was calculated using Logan plot with the full dynamic PET and an image-derived input function (IDIF) from the carotid arteries. IDIF was scaled by a calibration factor derived from all the measured plasma activity concentrations. The calculated V T values were used for training a random forest regressor. As input features for the model, we used three late PET frames (60–70, 70–80, and 80–90 min p.i.), the ASL image reflecting perfusion, the voxel coordinates, the lesion mask, and the five plasma activity concentrations. The algorithm was validated with the leave-one-out approach. To estimate the impact of the individual features on the algorithm's performance, we used Shapley Additive Explanations (SHAP). Having determined that the three late PET frames and the plasma activity concentrations were the most important features, we tested a simplified quantification approach consisting of dividing a late PET frame by a plasma activity concentration. All the combinations of frames/samples were compared by means of concordance correlation coefficient and Bland-Altman plots. When using all the input features, the algorithm predicted V T values with high accuracy (87.8 ± 8.3%) for both lesion and non-lesion voxels. The SHAP values demonstrated high impact of the late PET frames (60–70, 70–80, and 80–90 min p.i.) and plasma activity concentrations on the V T prediction, while the influence of the ASL-derived perfusion, voxel coordinates, and the lesion mask was low. Among all the combinations of the late PET frames and plasma activity concentrations, the 70–80 min p.i. frame divided by the 30 min p.i. plasma sample produced the closest V T estimate in the ischemic lesion. Reliable TSPO PET quantification is achievable by using a single late PET frame divided by a late blood sample activity concentration. [ABSTRACT FROM AUTHOR]

Published
2024
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91. Early-phase [18F]PI-2620 tau-PET imaging as a surrogate marker of neuronal injury

Author

Beyer, Leonie, Nitschmann, Alexander, Barthel, Henryk, van Eimeren, Thilo, Unterrainer, Marcus, Sauerbeck, Julia, Marek, Ken, Song, Mengmeng, Palleis, Carla, Respondek, Gesine, Hammes, Jochen, Barbe, Michael T., Onur, Özgür, Jessen, Frank, Saur, Dorothee, Schroeter, Matthias L., Rumpf, Jost-Julian, Rullmann, Michael, Schildan, Andreas, Patt, Marianne, Neumaier, Bernd, Barret, Olivier, Madonia, Jennifer, Russell, David S., Stephens, Andrew W., Roeber, Sigrun, Herms, Jochen, Bötzel, Kai, Levin, Johannes, Classen, Joseph, Höglinger, Günter U., Bartenstein, Peter, Villemagne, Victor, Drzezga, Alexander, Seibyl, John, Sabri, Osama, and Brendel, Matthias

Published
2020
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92. Mapping 3-year changes in gray matter and metabolism in Aβ-positive nondemented subjects

Author

Caballero, Miguel Ángel Araque, Brendel, Matthias, Delker, Andreas, Ren, Jinyi, Rominger, Axel, Bartenstein, Peter, Dichgans, Martin, Weiner, Michael W, Ewers, Michael, and Initative, Alzheimer's Disease Neuroimaging

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Alzheimer's Disease, Brain Disorders, Biomedical Imaging, Dementia, Clinical Research, Aging, Alzheimer's Disease including Alzheimer's Disease Related Dementias (AD/ADRD), Acquired Cognitive Impairment, Neurodegenerative, Neurosciences, Detection, screening and diagnosis, 4.1 Discovery and preclinical testing of markers and technologies, Neurological, Aged, Aged, 80 and over, Amyloid beta-Peptides, Atrophy, Cognitive Dysfunction, Female, Glucose, Gray Matter, Humans, Magnetic Resonance Imaging, Male, Positron-Emission Tomography, Time Factors, Longitudinal, Neurodegeneration, Alzheimer's, Neuroimaging, Multivariate, Multimodal, Alzheimer's Disease Neuroimaging Initative, Neurology & Neurosurgery, Biological psychology
Abstract

Gray matter (GM) atrophy and brain glucose hypometabolism are already detected in the predementia stages of Alzheimer's disease (AD), but the regional and longitudinal associations between the two are not well understood. Here, we analyzed the patterns of longitudinal atrophy (magnetic resonance imaging [MRI]) and (18)F-Fluorodeoxyglucose-positron emission tomography ([18F]FDG-PET) metabolism decline in 40 cognitively healthy control (HC) and 52 mildly impaired (mild cognitive impairment [MCI]) subjects during 3 years. Based on cerebrospinal fluid and brain amyloid-PET, the subjects were divided into amyloid-beta (Aβ)- and Aβ+ subgroups. In voxel-based and region of interest analyses, we compared the 3-year rates of change in GM and glucose metabolism between Aβ-subgroups, within each diagnostic group. In joint-independent component analyses, we assessed the patterns of covariation between longitudinal change in GM volume and glucose metabolism. MCI-Aβ+ showed faster atrophy than MCI-Aβ- within the temporal, medial temporal, and medial parietal lobes. HC-Aβ+ showed faster atrophy within the precuneus than HC-Aβ-. For FDG-PET metabolism, MCI-Aβ+ exhibited faster decline than MCI-Aβ- in temporoparietal regions, whereas no differences between HC subgroups were observed. Joint-independent component analysis showed that accelerated atrophy and metabolism decline correlated across distant brain regions for MCI-Aβ+. In conclusion, abnormally increased levels of Aβ in nondemented subjects were associated with accelerated decline in both GM and glucose metabolism, where both types of neurodegeneration progress in spatially divergent patterns.

Published
2015

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