@article{IsraelRiehlButtetal.2023,
  author    = {Israel, Ina and Riehl, Gabriele and Butt, Elke and Buck, Andreas K. and Samnick, Samuel},
  title     = {Gallium-68-labeled KISS1-54 peptide for mapping KISS1 receptor via PET: initial evaluation in human tumor cell lines and in tumor-bearing mice},
  series = {Pharmaceuticals},
  volume    = {17},
  journal   = {Pharmaceuticals},
  number    = {1},
  issn      = {1424-8247},
  doi       = {10.3390/ph17010044},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-355898},
  year      = {2023},
  abstract  = {Kisspeptins (KPs, KISS1) and their receptor (KISS1R) play a pivotal role as metastasis suppressor for many cancers. Low or lost KP expression is associated with higher tumor grade, increased metastatic potential, and poor prognosis. Therefore, KP expression has prognostic relevance and correlates with invasiveness in cancers. Furthermore, KISS1R represents a very promising target for molecular imaging and therapy for KISS1R-expressing tumors. The goal of this study was to evaluate the developed KISS1-54 derivative, [\(^{68}\)Ga]KISS1-54, as a PET-imaging probe for KISS1R-expressing tumors. The NODAGA-KISS1-54 peptide was labeled by Gallium-68, and the stability of the resulting [\(^{68}\)Ga]KISS1-54 evaluated in injection solution and human serum, followed by an examination in different KISS1R-expressing tumor cell lines, including HepG2, HeLa, MDA-MB-231, MCF7, LNCap, SK-BR-3, and HCT116. Finally, [\(^{68}\)Ga]KISS1-54 was tested in LNCap- and MDA-MB-231-bearing mice, using µ-PET, assessing its potential as an imaging probe for PET. [\(^{68}\)Ga]KISS1-54 was obtained in a 77 ± 7\% radiochemical yield and at a >99\% purity. The [\(^{68}\)Ga]KISS1-54 cell uptake amounted to 0.6-4.4\% per 100,000 cells. Moreover, the accumulation of [\(^{68}\)Ga]KISS1-54 was effectively inhibited by nonradioactive KISS1-54. In [\(^{68}\)Ga]KISS1-54-PET, KISS1R-positive LNCap-tumors were clearly visualized as compared to MDA-MB-231-tumor implant with predominantly intracellular KISS1R expression. Our first results suggest that [\(^{68}\)Ga]KISS1-54 is a promising candidate for a radiotracer for targeting KISS1R-expressing tumors via PET.},
  language  = {en}
}
@article{MichalskiSchloetelburgHartrampfetal.2023,
  author    = {Michalski, Kerstin and Schl{\"o}telburg, Wiebke and Hartrampf, Philipp E. and Kosmala, Aleksander and Buck, Andreas K. and Hahner, Stefanie and Schirbel, Andreas},
  title     = {Radiopharmaceuticals for treatment of adrenocortical carcinoma},
  series = {Pharmaceuticals},
  volume    = {17},
  journal   = {Pharmaceuticals},
  number    = {1},
  issn      = {1424-8247},
  doi       = {10.3390/ph17010025},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-355901},
  year      = {2023},
  abstract  = {Adrenocortical carcinoma (ACC) represents a rare tumor entity with limited treatment options and usually rapid tumor progression in case of metastatic disease. As further treatment options are needed and ACC metastases are sensitive to external beam radiation, novel theranostic approaches could complement established therapeutic concepts. Recent developments focus on targeting adrenal cortex-specific enzymes like the theranostic twin [\(^{123/131}\)I]IMAZA that shows a good image quality and a promising therapeutic effect in selected patients. But other established molecular targets in nuclear medicine such as the C-X-C motif chemokine receptor 4 (CXCR4) could possibly enhance the therapeutic regimen as well in a subgroup of patients. The aims of this review are to give an overview of innovative radiopharmaceuticals for the treatment of ACC and to present the different molecular targets, as well as to show future perspectives for further developments since a radiopharmaceutical with a broad application range is still warranted.},
  language  = {en}
}
@article{TranGiaDenisBacelarFerreiraetal.2023,
  author    = {Tran-Gia, Johannes and Denis-Bacelar, Ana M. and Ferreira, Kelley M. and Robinson, Andrew P. and Bobin, Christophe and Bonney, Lara M. and Calvert, Nicholas and Collins, Sean M. and Fenwick, Andrew J. and Finocchiaro, Domenico and Fioroni, Federica and Giannopoulou, Katerina and Grassi, Elisa and Heetun, Warda and Jewitt, Stephanie J. and Kotzasarlidou, Maria and Ljungberg, Michael and Louren{\c{c}}o, Val{\´e}rie and McGowan, Daniel R. and Mewburn-Crook, Jamie and Sabot, Benoit and Scuffham, James and Sj{\"o}green Gleisner, Katarina and Solc, Jaroslav and Thiam, Cheick and Tipping, Jill and Wevrett, Jill and Lassmann, Michael},
  title     = {On the use of solid 133Ba sources as surrogate for liquid 131I in SPECT/CT calibration: a European multi-centre evaluation},
  series = {EJNMMI Physics},
  volume    = {10},
  journal   = {EJNMMI Physics},
  organization    = {The MRT Dosimetry Collaboration},
  doi       = {10.1186/s40658-023-00582-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357740},
  year      = {2023},
  abstract  = {Introduction Commissioning, calibration, and quality control procedures for nuclear medicine imaging systems are typically performed using hollow containers filled with radionuclide solutions. This leads to multiple sources of uncertainty, many of which can be overcome by using traceable, sealed, long-lived surrogate sources containing a radionuclide of comparable energies and emission probabilities. This study presents the results of a quantitative SPECT/CT imaging comparison exercise performed within the MRTDosimetry consortium to assess the feasibility of using 133Ba as a surrogate for 131I imaging. Materials and methods Two sets of four traceable 133Ba sources were produced at two National Metrology Institutes and encapsulated in 3D-printed cylinders (volume range 1.68-107.4 mL). Corresponding hollow cylinders to be filled with liquid 131I and a mounting baseplate for repeatable positioning within a Jaszczak phantom were also produced. A quantitative SPECT/CT imaging comparison exercise was conducted between seven members of the consortium (eight SPECT/CT systems from two major vendors) based on a standardised protocol. Each site had to perform three measurements with the two sets of 133Ba sources and liquid 131I. Results As anticipated, the 131I pseudo-image calibration factors (cps/MBq) were higher than those for 133Ba for all reconstructions and systems. A site-specific cross-calibration reduced the performance differences between both radionuclides with respect to a cross-calibration based on the ratio of emission probabilities from a median of 12-1.5\%. The site-specific cross-calibration method also showed agreement between 133Ba and 131I for all cylinder volumes, which highlights the potential use of 133Ba sources to calculate recovery coefficients for partial volume correction. Conclusion This comparison exercise demonstrated that traceable solid 133Ba sources can be used as surrogate for liquid 131I imaging. The use of solid surrogate sources could solve the radiation protection problem inherent in the preparation of phantoms with 131I liquid activity solutions as well as reduce the measurement uncertainties in the activity. This is particularly relevant for stability measurements, which have to be carried out at regular intervals.},
  language  = {en}
}
@phdthesis{Kemmer2024,
  author    = {Kemmer, Luisa Diana},
  title     = {Darstellung von Inflammation in Atherosklerose mit dem CXCR4-gerichteten PET-Tracer \(^{68}\)Ga-Pentixafor im Vergleich zur \(^{18}\)F-FDG-PET/CT},
  doi       = {10.25972/OPUS-36001},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-360013},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Herz-Kreislauf-Erkrankungen z{\"a}hlen zu den h{\"a}ufigsten Todesursachen weltweit. Ein ihr zugrundeliegender pathologischer Prozess ist die Atherosklerose. Die Ruptur eines atheroskelrotischen Plaques kann lebensbedrohlich sein. Derzeit existieren weder ein evaluierter Biomarker noch eine Bildgebungstechnik, die das Risiko einer solchen Plaqueruptur und eines nachfolgenden akuten kardiovaskul{\"a}ren Ereignisses vorhersagen k{\"o}nnen. Um die bildgebenden Verfahren zur Detektion der Atherosklerose zu optimieren, wurde in dieser Dissertationsarbeit untersucht, ob der PET/CT-Tracer 68Ga-Pentixafor im Vergleich zu 18F-FDG bessere Ergebnisse in der Diagnostik der Atherosklerose erzielen kann. Insgesamt wurden 144 onkologische Patienten in die Studie einbezogen, bei denen die 18F-FDG-PET/CT sowie 68Ga-Pentifaxor-PET/CT aus klinischen Gr{\"u}nden indiziert waren. Befunde, bei denen eine gegen{\"u}ber dem Hintergrund vermehrte Speicherung ohne physiologische Erkl{\"a}rung nachgewiesen werden konnte, wurden als positiv bewertet. Um Unterschiede zwischen den Patienten außer Acht lassen zu k{\"o}nnen, wurde die target-to-background-ratio (TBR) berechnet. Zur Beschreibung der Speicherintensit{\"a}t einer L{\"a}sion wurde der standardized uptake value (SUV) bestimmt. Nach Auswertung der Daten zeigte sich eine m{\"a}ßige Korrelation der Anzahl von 68Ga-Pentixafor-positiven L{\"a}sionen mit der Anzahl der 18F-FDG positiven L{\"a}sionen. Die CXCR4-gerichtete Bildgebung mit 68Ga-Pentixafor identifizierte mehr L{\"a}sionen als die 18F-FDG-PET/CT. Bez{\"u}glich ihres Verteilungsmusters wiesen die beiden Tracer eine geringe Korrelation auf. Die Aufnahmeintensit{\"a}t beider Tracer korrelierte umgekehrt mit dem Ausmaß der Verkalkung. Stark verkalkte Plaques zeigten die niedrigste Traceraufnahme f{\"u}r beide PET-Tracer. Weitere Studien zur Aufkl{\"a}rung der zugrunde liegenden biologischen Mechanismen und Quellen der CXCR4-Positivit{\"a}t sind in hohem Maße gerechtfertigt.},
  subject      = {Arteriosklerose},
  language  = {de}
}
@phdthesis{Heinrich2024,
  author    = {Heinrich, Marieke},
  title     = {Bildgebung des Prostatakarzinoms im PSMA-PET/CT: Die halbautomatische Quantifizierung des Tumorvolumens zeigt (noch) keine verbesserte Pr{\"a}diktion des Krankheitsverlaufs},
  doi       = {10.25972/OPUS-35968},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-359684},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Die molekularen Parameter PSMA-TV und TL-PSMA im 68Ga-PSMA PET/CT leiten sich ab von MTV und TLG im FDG PET/CT. Mit der vorliegenden Arbeit wurden die Grenzen neuer Autosegmentierungsprogramme durch eine maximale Belastung mit großen Tumorvolumina von Patienten unter taxanbasierter Chemotherapie ausgelotet. Die Programme Syngo.via und FIJI kamen zu vergleichbaren Ergebnissen. Patienten mit einem Gleason Score von 8-10 zeigten unter Therapie eine signifikante Zunahme des PSMA-TV und TL-PSMA im Gegensatz zu Patienten mit Gleason Score 6-7b. Ein hoher PSA-Wert korrelierte zu allen Zeitpunkten signifikant mit einem hohen PSMA-TV und TL-PSMA, ebenso korrelierte ein steigender PSA-Wert signifikant mit steigenden Werten in PSMA-TV und TL-PSMA. Patienten mit einem biochemischen Progress und einem Progress nach modifiziertem PERCIST zeigten vor Therapie ein signifikant h{\"o}heres PSMA-TV und TL-PSMA als Patienten ohne Progress und unter Therapie eine signifikante Zunahme des PSMA-TV und TL-PSMA im Vergleich zu Patienten ohne Progress. Eine Einteilung des Therapieansprechens aller Patienten in CR, PR, SD und PD nach PSMA-TV, TL-PSMA, PSA-Wert und modifiziertem PERCIST stimmte nicht in allen Patienten {\"u}berein. Ein signifikant k{\"u}rzeres Gesamt{\"u}berleben zeigten lediglich Patienten mit einem nach dem PSA-Wert definiertem Progress. Im praktischen Vergleich der beiden Programme ben{\"o}tigte Syngo.via f{\"u}r eine komplette Segmentierung signifikant mehr Zeit als FIJI, vor allem da der Wechsel von VOI zu VOI signifikant l{\"a}nger dauerte. Unabh{\"a}ngig vom Autosegmentierungsprogramm dauerte eine komplette Segmentierung l{\"a}nger, je gr{\"o}ßer das PSMA-TV und das TL-PSMA war, je mehr VOIs das Programm automatisch setzte und je mehr VOIs manuell gel{\"o}scht und neu gesetzt wurden. In der Gesamtschau bieten PSMA-TV und TL-PSMA in Kombination mit den sich schnell weiterentwickelnden Autosegmentierungs-Programmen die M{\"o}glichkeit, auch sehr hohe Tumorlasten des PCas objektiv und vergleichbar zu beschreiben.},
  subject      = {Hormonrefrakt{\"a}rer Prostatakrebs},
  language  = {de}
}
@article{LisowskiHartrampfHasenaueretal.2023,
  author    = {Lisowski, Dominik and Hartrampf, Philipp E. and Hasenauer, Natalie and Nickl, Vera and Monoranu, Camelia-Maria and Tamihardja, J{\"o}rg},
  title     = {Complete loss of E-cadherin expression in a rare case of metastatic malignant meningioma: a case report},
  series = {BMC Neurology},
  volume    = {23},
  journal   = {BMC Neurology},
  doi       = {10.1186/s12883-023-03450-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-357996},
  year      = {2023},
  abstract  = {Background Hematogenous tumor spread of malignant meningiomas occurs very rarely but is associated with very poor prognosis. Case presentation We report an unusual case of a patient with a malignant meningioma who developed multiple metastases in bones, lungs and liver after initial complete resection of the primary tumor. After partial hepatic resection, specimens were histologically analyzed, and a complete loss of E-cadherin adhesion molecules was found. No oncogenic target mutations were found. The patient received a combination of conventional radiotherapy and peptide receptor radionuclide therapy (PRRT). Due to aggressive tumor behavior and rapid spread of metastases, the patient deceased after initiation of treatment. Conclusions E-cadherin downregulation is associated with a higher probability of tumor invasion and distant metastasis formation in malignant meningioma. Up to now, the efficacy of systemic therapy, including PRRT, is very limited in malignant meningioma patients.},
  language  = {en}
}
@article{JanzWalzCirnuetal.2024,
  author    = {Janz, Anna and Walz, Katharina and Cirnu, Alexandra and Surjanto, Jessica and Urlaub, Daniela and Leskien, Miriam and Kohlhaas, Michael and Nickel, Alexander and Brand, Theresa and Nose, Naoko and W{\"o}rsd{\"o}rfer, Philipp and Wagner, Nicole and Higuchi, Takahiro and Maack, Christoph and Dudek, Jan and Lorenz, Kristina and Klopocki, Eva and Erg{\"u}n, S{\"u}leyman and Duff, Henry J. and Gerull, Brenda},
  title     = {Mutations in DNAJC19 cause altered mitochondrial structure and increased mitochondrial respiration in human iPSC-derived cardiomyocytes},
  series = {Molecular Metabolism},
  volume    = {79},
  journal   = {Molecular Metabolism},
  issn      = {2212-8778},
  doi       = {10.1016/j.molmet.2023.101859},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350393},
  year      = {2024},
  abstract  = {Highlights • Loss of DNAJC19's DnaJ domain disrupts cardiac mitochondrial structure, leading to abnormal cristae formation in iPSC-CMs. • Impaired mitochondrial structures lead to an increased mitochondrial respiration, ROS and an elevated membrane potential. • Mutant iPSC-CMs show sarcomere dysfunction and a trend to more arrhythmias, resembling DCMA-associated cardiomyopathy. Background Dilated cardiomyopathy with ataxia (DCMA) is an autosomal recessive disorder arising from truncating mutations in DNAJC19, which encodes an inner mitochondrial membrane protein. Clinical features include an early onset, often life-threatening, cardiomyopathy associated with other metabolic features. Here, we aim to understand the metabolic and pathophysiological mechanisms of mutant DNAJC19 for the development of cardiomyopathy. Methods We generated induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) of two affected siblings with DCMA and a gene-edited truncation variant (tv) of DNAJC19 which all lack the conserved DnaJ interaction domain. The mutant iPSC-CMs and their respective control cells were subjected to various analyses, including assessments of morphology, metabolic function, and physiological consequences such as Ca\(^{2+}\) kinetics, contractility, and arrhythmic potential. Validation of respiration analysis was done in a gene-edited HeLa cell line (DNAJC19tv\(_{HeLa}\)). Results Structural analyses revealed mitochondrial fragmentation and abnormal cristae formation associated with an overall reduced mitochondrial protein expression in mutant iPSC-CMs. Morphological alterations were associated with higher oxygen consumption rates (OCRs) in all three mutant iPSC-CMs, indicating higher electron transport chain activity to meet cellular ATP demands. Additionally, increased extracellular acidification rates suggested an increase in overall metabolic flux, while radioactive tracer uptake studies revealed decreased fatty acid uptake and utilization of glucose. Mutant iPSC-CMs also showed increased reactive oxygen species (ROS) and an elevated mitochondrial membrane potential. Increased mitochondrial respiration with pyruvate and malate as substrates was observed in mutant DNAJC19tv HeLa cells in addition to an upregulation of respiratory chain complexes, while cellular ATP-levels remain the same. Moreover, mitochondrial alterations were associated with increased beating frequencies, elevated diastolic Ca\(^{2+}\) concentrations, reduced sarcomere shortening and an increased beat-to-beat rate variability in mutant cell lines in response to β-adrenergic stimulation. Conclusions Loss of the DnaJ domain disturbs cardiac mitochondrial structure with abnormal cristae formation and leads to mitochondrial dysfunction, suggesting that DNAJC19 plays an essential role in mitochondrial morphogenesis and biogenesis. Moreover, increased mitochondrial respiration, altered substrate utilization, increased ROS production and abnormal Ca\(^{2+}\) kinetics provide insights into the pathogenesis of DCMA-related cardiomyopathy.},
  language  = {en}
}
@article{HartrampfWeinzierlBucketal.2022,
  author    = {Hartrampf, Philipp E. and Weinzierl, Franz-Xaver and Buck, Andreas K. and Rowe, Steven P. and Higuchi, Takahiro and Seitz, Anna Katharina and K{\"u}bler, Hubert and Schirbel, Andreas and Essler, Markus and Bundschuh, Ralph A. and Werner, Rudolf A.},
  title     = {Matched-pair analysis of [\(^{177}\)Lu]Lu-PSMA I\&T and [\(^{177}\)Lu]Lu-PSMA-617 in patients with metastatic castration-resistant prostate cancer},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {49},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {9},
  doi       = {10.1007/s00259-022-05744-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324581},
  pages     = {3269-3276},
  year      = {2022},
  abstract  = {Background Labelled with lutetium-177, the urea-based small molecules PSMA I\&T and PSMA-617 are the two agents most frequently used for radioligand therapy (RLT) in patients with advanced metastatic castration-resistant and prostate-specific membrane antigen (PSMA) expressing prostate cancer (mCRPC). In this matched-pair analysis, we aimed to compare the toxicity and efficacy of both agents for PSMA-directed RLT. Materials and methods A total of 110 mCRPC patients from two centres were accrued, 55 individuals treated with [\(^{177}\)Lu]Lu-PSMA I\&T, and a matched cohort of 55 patients treated with [\(^{177}\)Lu]Lu-PSMA-617. Matching criteria included age at the first cycle, Gleason score, prostate-specific antigen (PSA) values, and previous taxane-based chemotherapy. Using common terminology criteria for adverse events (CTCAE v. 5.0), toxicity profiles were investigated (including bone marrow and renal toxicity). Overall survival (OS) between both groups was compared. Results Toxicity assessment revealed grade III anaemia in a single patient (1.8\%) for [\(^{177}\)Lu]Lu-PSMA I\&T and five (9.1\%) for [\(^{177}\)Lu]Lu-PSMA-617. In addition, one (1.9\%) grade III thrombopenia for [\(^{177}\)Lu]Lu-PSMA-617 was recorded. Apart from that, no other grade III/IV toxicities were present. A median OS of 12 months for patients treated with [\(^{177}\)Lu]Lu-PSMA I\&T did not differ significantly when compared to patients treated with [\(^{177}\)Lu]Lu-PSMA-617 (median OS, 13 months; P = 0.89). Conclusion In this matched-pair analysis of patients receiving one of the two agents most frequently applied for PSMA RLT, the rate of clinically relevant toxicities was low for both compounds. In addition, no relevant differences for OS were observed.},
  language  = {en}
}
@article{LinzBrandsKertelsetal.2021,
  author    = {Linz, Christian and Brands, Roman C. and Kertels, Olivia and Dierks, Alexander and Brumberg, Joachim and Gerhard-Hartmann, Elena and Hartmann, Stefan and Schirbel, Andreas and Serfling, Sebastian and Zhi, Yingjun and Buck, Andreas K. and K{\"u}bler, Alexander and Hohm, Julian and Lapa, Constantin and Kircher, Malte},
  title     = {Targeting fibroblast activation protein in newly diagnosed squamous cell carcinoma of the oral cavity - initial experience and comparison to [\(^{18}\)F]FDG PET/CT and MRI},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {48},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {12},
  issn      = {1619-7070},
  doi       = {10.1007/s00259-021-05422-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-307246},
  pages     = {3951-3960},
  year      = {2021},
  abstract  = {Purpose While [\(^{18}\)F]-fluorodeoxyglucose ([\(^{18}\)F]FDG) is the standard for positron emission tomography/computed tomography (PET/CT) imaging of oral squamous cell carcinoma (OSCC), diagnostic specificity is hampered by uptake in inflammatory cells such as neutrophils or macrophages. Recently, molecular imaging probes targeting fibroblast activation protein α (FAP), which is overexpressed in a variety of cancer-associated fibroblasts, have become available and might constitute a feasible alternative to FDG PET/CT. Methods Ten consecutive, treatment-na{\"i}ve patients (8 males, 2 females; mean age, 62 ± 9 years) with biopsy-proven OSCC underwent both whole-body [\(^{18}\)F]FDG and [\(^{68}\)Ga]FAPI-04 (FAP-directed) PET/CT for primary staging prior to tumor resection and cervical lymph node dissection. Detection of the primary tumor, as well as the presence and number of lymph node and distant metastases was analysed. Intensity of tracer accumulation was assessed by means of maximum (SUV\(_{max}\)) and peak (SUV\(_{peak}\) standardized uptake values. Histological work-up including immunohistochemical staining for FAP served as standard of reference. Results [\(^{18}\)F]FDG and FAP-directed PET/CT detected all primary tumors with a SUVmax of 25.5 ± 13.2 (FDG) and 20.5 ± 6.4 (FAP-directed) and a SUVpeak of 16.1 ± 10.3 ([\(^{18}\)F]FDG) and 13.8 ± 3.9 (FAP-directed), respectively. Regarding cervical lymph node metastases, FAP-directed PET/CT demonstrated comparable sensitivity (81.3\% vs. 87.5\%; P = 0.32) and specificity (93.3\% vs. 81.3\%; P = 0.16) to [\(^{18}\)F]FDG PET/CT. FAP expression on the cell surface of cancer-associated fibroblasts in both primary lesions as well as lymph nodes metastases was confirmed in all samples. Conclusion FAP-directed PET/CT in OSCC seems feasible. Future research to investigate its potential to improve patient staging is highly warranted.},
  language  = {en}
}
@article{GieselKratochwilSchlittenhardtetal.2021,
  author    = {Giesel, Frederik L. and Kratochwil, Clemens and Schlittenhardt, Joel and Dendl, Katharina and Eiber, Matthias and Staudinger, Fabian and Kessler, Lukas and Fendler, Wolfgang P. and Lindner, Thomas and Koerber, Stefan A. and Cardinale, Jens and Sennung, David and Roehrich, Manuel and Debus, Juergen and Sathekge, Mike and Haberkorn, Uwe and Calais, Jeremie and Serfling, Sebastian and Buck, Andreas L.},
  title     = {Head-to-head intra-individual comparison of biodistribution and tumor uptake of \(^{68}\)Ga-FAPI and \(^{18}\)F-FDG PET/CT in cancer patients},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {48},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {13},
  issn      = {1619-7070},
  doi       = {10.1007/s00259-021-05307-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-307252},
  pages     = {4377-4385},
  year      = {2021},
  abstract  = {Purpose FAPI ligands (fibroblast activation protein inhibitor), a novel class of radiotracers for PET/CT imaging, demonstrated in previous studies rapid and high tumor uptake. The purpose of this study is the head-to-head intra-individual comparison of \(^{68}\)Ga-FAPI versus standard-of-care \(^{18}\)F-FDG in PET/CT in organ biodistribution and tumor uptake in patients with various cancers. Material and Methods This international retrospective multicenter analysis included PET/CT data from 71 patients from 6 centers who underwent both \(^{68}\)Ga-FAPI and \(^{18}\)F-FDG PET/CT within a median time interval of 10 days (range 1-89 days). Volumes of interest (VOIs) were manually drawn in normal organs and tumor lesions to quantify tracer uptake by SUVmax and SUVmean. Furthermore, tumor-to-background ratios (TBR) were generated (SUVmax tumor/ SUVmax organ). Results A total of 71 patients were studied of, which 28 were female and 43 male (median age 60). In 41 of 71 patients, the primary tumor was present. Forty-three of 71 patients exhibited 162 metastatic lesions. \(^{68}\)Ga-FAPI uptake in primary tumors and metastases was comparable to 18F-FDG in most cases. The SUVmax was significantly lower for \(^{68}\)Ga-FAPI than \(^{18}\)F-FDG in background tissues such as the brain, oral mucosa, myocardium, blood pool, liver, pancreas, and colon. Thus, \(^{68}\)Ga-FAPI TBRs were significantly higher than 18F-FDG TBRs in some sites, including liver and bone metastases. Conclusion Quantitative tumor uptake is comparable between \(^{68}\)Ga-FAPI and \(^{18}\)F-FDG, but lower background uptake in most normal organs results in equal or higher TBRs for \(^{68}\)Ga-FAPI. Thus, \(^{68}\)Ga-FAPI PET/CT may yield improved diagnostic information in various cancers and especially in tumor locations with high physiological \(^{18}\)F-FDG uptake.},
  language  = {en}
}
@phdthesis{Boeser2024,
  author    = {B{\"o}ser, Janis},
  title     = {Einfluss der PSMA-PET/CT auf das psychische Befinden von Patienten mit Prostatakarzinom},
  doi       = {10.25972/OPUS-35204},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-352046},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Das fr{\"u}hzeitige Erkennen psychoonkologischer Belastungen ist Bestandteil des optimalen therapeutischen Managements von Tumorpatienten. Nur wenige, widerspr{\"u}chliche Studien untersuchten bisher das psychische Befinden im Verlauf einer PET/CT. Bezogen auf das Prostatakarzinom gibt es bislang keine spezifische Studie, obwohl es die h{\"a}ufigste onkologische Erkrankung des Mannes darstellt. Aufgrund der insgesamt guten Prognose wird von einer geringeren psychischen Belastung ausgegangen. Mithilfe dieser Studie sollte durch Kombination etablierter Frageb{\"o}gen das psychische Befinden im Verlauf der PET/CT explorativ untersucht werden. Von Oktober 2018 bis Februar 2020 wurde 531 m{\"a}nnlichen Patienten der Nuklearmedizin des Universit{\"a}tsklinikums W{\"u}rzburg die Teilnahme angeboten. N = 85 Patienten (n = 38 Patienten mit Prostatakarzinom sowie n = 47 Patienten mit anderen malignen Erkrankungen) stimmten einer vollst{\"a}ndigen Teilnahme zu. Es wurden zwei Messzeitpunkte (T1 nach Durchf{\"u}hrung der PET/CT; T2 nach Ergebnismitteilung) festgelegt. Als Messinstrumente wurden der PA-F-KF, QUICC, DT, STAI-X1, PANAS und ein Selbsteinsch{\"a}tzungsbogen verwendet. 24 \% (T1) bzw. 35 \% (T2) der Patienten mit Prostatakarzinom gaben eine dysfunktionale Progredienzangst an, 55 \% (T1+T2) eine pathologische psychische Belastung. 53 \% (T1) bzw. 50 \% (T2) der Patienten zeigten eine relevant erh{\"o}hte Zustandsangst. Die Progredienzangst stieg nach Ergebnismitteilung an (p = 0,048; η² = 0,106), die Ungewissheit {\"u}ber den Stand der Erkrankung (p = 0,014; η² = 0,165) und Bew{\"a}ltigbarkeit des Alltags (p = 0,016; η² = 0,163) reduzierten sich. Allgemeine {\"A}ngste wie die Zustandsangst, der Distress und negative Affekte ver{\"a}nderten sich nicht. PSA-Werte ohne bildmorphologisches Korrelat l{\"o}sten eine gr{\"o}ßere Unsicherheit bez{\"u}glich des aktuellen Krankheitszustandes aus (p = 0,029; η² = 0,128). J{\"u}ngere Patienten zeigten vor (p = 0,005; η² = 0,207) und nach (p = 0,001; η² = 0,290) Ergebnismitteilung eine h{\"o}here Angst um ihre Berufst{\"a}tigkeit und gaben eine geringere Erleichterung nach Ergebnismitteilung (p = 0,016; η² = 0,165) an. Als Limitationen sind die geringe Fallzahl und Teilnahmequote, multiple Testung und fehlende Erfragung psychischer Erkrankungen zu beachten. Insgesamt zeigen sich eine hohe psychische Belastung und {\"A}ngste im Verlauf der PET/CT. Patienten mit Prostatakarzinom sind zu diesem Zeitpunkt nicht weniger belastet als Patienten mit anderen malignen Erkrankungen.},
  subject      = {Angst},
  language  = {de}
}
@article{HiguchiSerflingRoweetal.2022,
  author    = {Higuchi, Takahiro and Serfling, Sebastian E. and Rowe, Steven P. and Werner, Rudolf A.},
  title     = {Therapeutic effects of lipid lowering medications on myocardial blood flow, inflammation, and sympathetic nerve activity using nuclear techniques},
  series = {Current Cardiology Reports},
  volume    = {24},
  journal   = {Current Cardiology Reports},
  number    = {12},
  doi       = {10.1007/s11886-022-01792-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324599},
  pages     = {1849-1853},
  year      = {2022},
  abstract  = {Purpose of Review Statins are routinely applied in patients with coronary artery disease, as they allow significantly to reduce blood cholesterol levels. Although those drugs are endorsed by current guidelines and prescribed routinely, a substantial portion of patients are still statin-intolerant and image-piloted strategies may then be helpful to identify patients that need further intensified treatment, e.g., to initiate treatment with proprotein convertase subtilisin / kexin type 9 inhibitors (PCSK9i). In addition, it has also been advocated that statins exhibit nonlipid, cardio-protective effects including improved cardiac nerve integrity, blood flow, and anti-inflammatory effects in congestive heart failure (HF) patients. Recent Findings In subjects after myocardial infarction treated with statins, \(^{123}\)I-metaiodobenzylguanidine (MIBG) scintigraphy has already revealed enhanced cardiac nerve function relative to patients without statins. In addition, all of those aforementioned statin-targeted pathways in HF can be visualized and monitored using dedicated cardiac radiotracers, e.g., \(^{123}\)I-MIBG or \(^{18}\)F-AF78 (for cardiac nerve function), \(^{18}\)F-flurpiridaz (to determine coronary flow) or \(^{68}\)Ga-PentixaFor (to detect inflammation). Summary Statins exhibit various cardio-beneficial effects, including improvement of cardiac nerve function, blood flow, and reduction of inflammation, which can all be imaged using dedicated nuclear cardiac radiotracers. This may allow for in vivo monitoring of statin-induced cardioprotection beyond lipid profiling in HF patients.},
  language  = {en}
}
@article{HartrampfBundschuhWeinzierletal.2022,
  author    = {Hartrampf, Philipp E. and Bundschuh, Ralph A. and Weinzierl, Franz-Xaver and Serfling, Sebastian E. and Kosmala, Aleksander and Seitz, Anna Katharina and K{\"u}bler, Hubert and Buck, Andreas K. and Essler, Markus and Werner, Rudolf A.},
  title     = {mCRPC patients with PSA fluctuations under radioligand therapy have comparable survival benefits relative to patients with sustained PSA decrease},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {49},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {13},
  doi       = {10.1007/s00259-022-05910-w},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324562},
  pages     = {4727-4735},
  year      = {2022},
  abstract  = {Introduction In men with metastatic castration-resistant prostate cancer (mCRPC) scheduled for prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT), biochemical response is assessed based on repeated measurements of prostate-specific antigen (PSA) levels. We aimed to determine overall survival (OS) in patients experiencing sustained PSA increase, decrease, or fluctuations during therapy. Materials and methods In this bicentric study, we included 176 mCRPC patients treated with PSMA-directed RLT. PSA levels were determined using blood samples prior to the first RLT and on the admission days for the following cycles. We calculated relative changes in PSA levels compared to baseline. Kaplan-Meier curves as well as log-rank test were used to compare OS of different subgroups, including patients with sustained PSA increase, decrease, or fluctuations (defined as change after initial decrease or increase after the first cycle). Results Sixty-one out of one hundred seventy-six (34.7\%) patients showed a sustained increase and 86/176 (48.8\%) a sustained decrease in PSA levels. PSA fluctuations were observed in the remaining 29/176 (16.5\%). In this subgroup, 22/29 experienced initial PSA decrease followed by an increase (7/29, initial increase followed by a decrease). Median OS of patients with sustained decrease in PSA levels was significantly longer when compared to patients with sustained increase of PSA levels (19 vs. 8 months; HR 0.35, 95\% CI 0.22-0.56; P < 0.001). Patients with PSA fluctuations showed a significantly longer median OS compared to patients with sustained increase of PSA levels (18 vs. 8 months; HR 0.49, 95\% CI 0.30-0.80; P < 0.01), but no significant difference relative to men with sustained PSA decrease (18 vs. 19 months; HR 1.4, 95\% CI 0.78-2.49; P = 0.20). In addition, in men experiencing PSA fluctuations, median OS did not differ significantly between patients with initial decrease or initial increase of tumor marker levels (16 vs. 18 months; HR 1.2, 95\% CI 0.38-4.05; P = 0.68). Conclusion Initial increase or decrease of PSA levels is sustained in the majority of patients undergoing RLT. Sustained PSA decrease was linked to prolonged survival and men with PSA fluctuations under treatment experienced comparable survival benefits. As such, transient tumor marker oscillations under RLT should rather not lead to treatment discontinuation, especially in the absence of radiological progression.},
  language  = {en}
}
@article{GoeringSchumannMuelleretal.2022,
  author    = {G{\"o}ring, Lukas and Schumann, Sarah and M{\"u}ller, Jessica and Buck, Andreas K. and Port, Matthias and Lassmann, Michael and Scherthan, Harry and Eberlein, Uta},
  title     = {Repair of a-particle-induced DNA damage in peripheral blood mononuclear cells after internal ex vivo irradiation with \(^{223}\)Ra},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {49},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {12},
  doi       = {10.1007/s00259-022-05860-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324557},
  pages     = {3981-3988},
  year      = {2022},
  abstract  = {Purpose As α-emitters for radiopharmaceutical therapies are administered systemically by intravenous injection, blood will be irradiated by α-particles that induce clustered DNA double-strand breaks (DSBs). Here, we investigated the induction and repair of DSB damage in peripheral blood mononuclear cells (PBMCs) as a function of the absorbed dose to the blood following internal ex vivo irradiation with [\(^{223}\)Ra]RaCl2. Methods Blood samples of ten volunteers were irradiated by adding [\(^{223}\)Ra]RaCl2 solution with different activity concentrations resulting in absorbed doses to the blood of 3 mGy, 25 mGy, 50 mGy and 100 mGy. PBMCs were isolated, divided in three parts and either fixed directly (d-samples) or after 4 h or 24 h culture. After immunostaining, the induced γ-H2AX α-tracks were counted. The time-dependent decrease in α-track frequency was described with a model assuming a repair rate R and a fraction of non-repairable damage Q. Results For 25 mGy, 50 mGy and 100 mGy, the numbers of α-tracks were significantly increased compared to baseline at all time points. Compared to the corresponding d-samples, the α-track frequency decreased significantly after 4 h and after 24 h. The repair rates R were (0.24 ± 0.05) h-1 for 25 mGy, (0.16 ± 0.04) h-1 for 50 mGy and (0.13 ± 0.02) h-1 for 100 mGy, suggesting faster repair at lower absorbed doses, while Q-values were similar. Conclusion The results obtained suggest that induction and repair of the DSB damage depend on the absorbed dose to the blood. Repair rates were similar to what has been observed for irradiation with low linear energy transfer.},
  language  = {en}
}
@article{HartrampfSeitzWeinzierletal.2022,
  author    = {Hartrampf, Philipp E. and Seitz, Anna Katharina and Weinzierl, Franz-Xaver and Serfling, Sebastian E. and Schirbel, Andreas and Rowe, Steven P. and K{\"u}bler, Hubert and Buck, Andreas K. and Werner, Rudolf A.},
  title     = {Baseline clinical characteristics predict overall survival in patients undergoing radioligand therapy with [\(^{177}\)Lu]Lu-PSMA I\&T during long-term follow-up},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {49},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {12},
  doi       = {10.1007/s00259-022-05853-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324573},
  pages     = {4262-4270},
  year      = {2022},
  abstract  = {Background Radioligand therapy (RLT) with \(^{177}\)Lu-labeled prostate-specific membrane antigen (PSMA) ligands is associated with prolonged overall survival (OS) in patients with advanced, metastatic castration-resistant prostate cancer (mCRPC). A substantial number of patients, however, are prone to treatment failure. We aimed to determine clinical baseline characteristics to predict OS in patients receiving [\(^{177}\)Lu]Lu-PSMA I\&T RLT in a long-term follow-up. Materials and methods Ninety-two mCRPC patients treated with [\(^{177}\)Lu]Lu-PSMA I\&T with a follow-up of at least 18 months were retrospectively identified. Multivariable Cox regression analyses were performed for various baseline characteristics, including laboratory values, Gleason score, age, prior therapies, and time interval between initial diagnosis and first treatment cycle (interval\(_{Diagnosis-RLT}\), per 12 months). Cutoff values for significant predictors were determined using receiver operating characteristic (ROC) analysis. ROC-derived thresholds were then applied to Kaplan-Meier analyses. Results Baseline C-reactive protein (CRP; hazard ratio [HR], 1.10, 95\% CI 1.02-1.18; P = 0.01), lactate dehydrogenase (LDH; HR, 1.07, 95\% CI 1.01-1.11; P = 0.01), aspartate aminotransferase (AST; HR, 1.16, 95\% CI 1.06-1.26; P = 0.001), and interval\(_{Diagnosis-RLT}\) (HR, 0.95, 95\% CI 0.91-0.99; P = 0.02) were identified as independent prognostic factors for OS. The following respective ROC-based thresholds were determined: CRP, 0.98 mg/dl (area under the curve [AUC], 0.80); LDH, 276.5 U/l (AUC, 0.83); AST, 26.95 U/l (AUC, 0.73); and interval\(_{Diagnosis-RLT}\), 43.5 months (AUC, 0.68; P < 0.01, respectively). Respective Kaplan-Meier analyses demonstrated a significantly longer median OS of patients with lower CRP, lower LDH, and lower AST, as well as prolonged interval\(_{Diagnosis-RLT}\) (P ≤ 0.01, respectively). Conclusion In mCRPC patients treated with [\(^{177}\)Lu]Lu-PSMA I\&T, baseline CRP, LDH, AST, and time interval until RLT initiation (thereby reflecting a possible indicator for tumor aggressiveness) are independently associated with survival. Our findings are in line with previous findings on [\(^{177}\)Lu]Lu-PSMA-617, and we believe that these clinical baseline characteristics may support the nuclear medicine specialist to identify long-term survivors.},
  language  = {en}
}
@article{BuckSerflingLindneretal.2022,
  author    = {Buck, Andreas K. and Serfling, Sebastian E. and Lindner, Thomas and H{\"a}nscheid, Heribert and Schirbel, Andreas and Hahner, Stefanie and Fassnacht, Martin and Einsele, Hermann and Werner, Rudolf A.},
  title     = {CXCR4-targeted theranostics in oncology},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {49},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {12},
  doi       = {10.1007/s00259-022-05849-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324545},
  pages     = {4133-4144},
  year      = {2022},
  abstract  = {A growing body of literature reports on the upregulation of C-X-C motif chemokine receptor 4 (CXCR4) in a variety of cancer entities, rendering this receptor as suitable target for molecular imaging and endoradiotherapy in a theranostic setting. For instance, the CXCR4-targeting positron emission tomography (PET) agent [\(^{68}\)Ga]PentixaFor has been proven useful for a comprehensive assessment of the current status quo of solid tumors, including adrenocortical carcinoma or small-cell lung cancer. In addition, [\(^{68}\)Ga]PentixaFor has also provided an excellent readout for hematological malignancies, such as multiple myeloma, marginal zone lymphoma, or mantle cell lymphoma. PET-based quantification of the CXCR4 capacities in vivo allows for selecting candidates that would be suitable for treatment using the theranostic equivalent [\(^{177}\)Lu]/[\(^{90}\)Y]PentixaTher. This CXCR4-directed theranostic concept has been used as a conditioning regimen prior to hematopoietic stem cell transplantation and to achieve sufficient anti-lymphoma/-tumor activity in particular for malignant tissues that are highly sensitive to radiation, such as the hematological system. Increasing the safety margin, pretherapeutic dosimetry is routinely performed to determine the optimal activity to enhance therapeutic efficacy and to reduce off-target adverse events. The present review will provide an overview of current applications for CXCR4-directed molecular imaging and will introduce the CXCR4-targeted theranostic concept for advanced hematological malignancies.},
  language  = {en}
}
@article{HiguchiWerner2023,
  author    = {Higuchi, Takahiro and Werner, Rudolf A.},
  title     = {Unfolding the cardioprotective potential of sigma-1 receptor-directed molecular imaging},
  series = {Journal of Nuclear Cardiology},
  volume    = {30},
  journal   = {Journal of Nuclear Cardiology},
  number    = {2},
  doi       = {10.1007/s12350-022-03077-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324600},
  pages     = {662-664},
  year      = {2023},
  abstract  = {No abstract available.},
  language  = {en}
}
@article{LambertiniHartrampfHiguchietal.2022,
  author    = {Lambertini, Alessandro and Hartrampf, Philipp E. and Higuchi, Takahiro and Serfling, Sebastian E. and Meybohm, Patrick and Schirbel, Andreas and Buck, Andreas K. and Werner, Rudolf A.},
  title     = {CXCR4-targeted molecular imaging after severe SARS-Cov-2 infection},
  series = {European Journal of Nuclear Medicine and Molecular Imaging},
  volume    = {50},
  journal   = {European Journal of Nuclear Medicine and Molecular Imaging},
  number    = {1},
  doi       = {10.1007/s00259-022-05932-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324619},
  pages     = {228-229},
  year      = {2022},
  abstract  = {No abstract available.},
  language  = {en}
}
@article{WeichHiguchiBundschuhetal.2022,
  author    = {Weich, Alexander and Higuchi, Takahiro and Bundschuh, Ralph A. and Lapa, Constantin and Serfling, Sebastian E. and Rowe, Steven P. and Pomper, Martin G. and Herrmann, Ken and Buck, Andreas K. and Derlin, Thorsten and Werner, Rudolf A.},
  title     = {Training on reporting and data system (RADS) for somatostatin-receptor targeted molecular imaging can reduce the test anxiety of inexperienced readers},
  series = {Molecular Imaging and Biology},
  volume    = {24},
  journal   = {Molecular Imaging and Biology},
  number    = {4},
  doi       = {10.1007/s11307-022-01712-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324645},
  pages     = {631-640},
  year      = {2022},
  abstract  = {Purpose For somatostatin receptor (SSTR)-positron emission tomography/computed tomography (PET/CT), a standardized framework termed SSTR-reporting and data system (RADS) has been proposed. We aimed to elucidate the impact of a RADS-focused training on reader's anxiety to report on SSTR-PET/CT, the motivational beliefs in learning such a system, whether it increases reader's confidence, and its implementation in clinical routine. Procedures A 3-day training course focusing on SSTR-RADS was conducted. Self-report questionnaires were handed out prior to the course (Pre) and thereafter (Post). The impact of the training on the following categories was evaluated: (1) test anxiety to report on SSTR-PET/CT, (2) motivational beliefs, (3) increase in reader's confidence, and (4) clinical implementation. To assess the effect size of the course, Cohen's d was calculated (small, d = 0.20; large effect, d = 0.80). Results Of 22 participants, Pre and Post were returned by 21/22 (95.5\%). In total, 14/21 (66.7\%) were considered inexperienced (IR, < 1 year experience in reading SSTR-PET/CTs) and 7/21 (33.3\%) as experienced readers (ER, > 1 year). Applying SSTR-RADS, a large decrease in anxiety to report on SSTR-PET/CT was noted for IR (d =  - 0.74, P = 0.02), but not for ER (d = 0.11, P = 0.78). For the other three categories motivational beliefs, reader's confidence, and clinical implementation, agreement rates were already high prior to the training and persisted throughout the course (P ≥ 0.21). Conclusions A framework-focused reader training can reduce anxiety to report on SSTR-PET/CTs, in particular for inexperienced readers. This may allow for a more widespread adoption of this system, e.g., in multicenter trials for better intra- and interindividual comparison of scan results.},
  language  = {en}
}
@article{BrumbergBlazhenetsSchroeteretal.2019,
  author    = {Brumberg, Joachim and Blazhenets, Ganna and Schr{\"o}ter, Nils and Frings, Lars and Jost, Wolfgang H. and Lapa, Constantin and Meyer, Philipp T.},
  title     = {Imaging cardiac sympathetic innervation with MIBG: linear conversion of the heart-to-mediastinum ratio between different collimators},
  series = {EJNMMI Physics},
  volume    = {6},
  journal   = {EJNMMI Physics},
  doi       = {10.1186/s40658-019-0250-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-221675},
  year      = {2019},
  abstract  = {Background The heart-to-mediastinum (H/M) ratio is a commonly used parameter to measure cardiac I-123 metaiodobenzylguanidine (MIBG) uptake. Since the H/M ratio is substantially influenced by the collimator type, we investigated whether an empirical linear conversion of H/M ratios between camera systems with low-energy (LE) and medium-energy (ME) collimator is possible. Methods We included 18 patients with parkinsonism who were referred to one of the two participating molecular imaging facilities for the evaluation of cardiac sympathetic innervation by MIBG scintigraphy. Two consecutive planar image datasets were acquired with LE and ME collimators at 4 h after MIBG administration. Linear regression analyses were performed to describe the association between the H/M ratios gained with both collimator settings, and the accuracy of a linear transfer of the H/M ratio between collimators and across centers was assessed using a leave-one-out procedure. Results H/M ratios acquired with LE and ME collimators showed a strong linear relationship both within each imaging facility (R\(^2\) = 0.99, p < 0.001 and R\(^2\) = 0.90, p < 0.001) and across centers (H/M-LE = 0.41 × H/M-ME + 0.63, R\(^2\) = 0.97, p < 0.001). A linear conversion of H/M ratios between collimators and across centers was estimated to be very accurate (mean absolute error 0.05 ± 0.04; mean relative absolute error 3.2 ± 2.6\%). Conclusions The present study demonstrates that a simple linear conversion of H/M ratios acquired with different collimators is possible with high accuracy. This should greatly facilitate the exchange of normative data between settings and pooling of data from different institutions.},
  language  = {en}
}