EJNMMI Rep
November 2024
Background: To investigate the ability of artificial intelligence (AI)-based and semi-quantitative dynamic contrast enhanced (DCE) multiparametric MRI (mpMRI), performed within [F]-PSMA-1007 PET/MRI, in differentiating benign from malignant prostate tissues in patients with primary prostate cancer (PC).
Results: A total of seven patients underwent whole-body [F]-PSMA-1007 PET/MRI examinations including a pelvic mpMRI protocol with T2w, diffusion weighted imaging (DWI) and DCE image series. Conventional analysis included visual reading of PET/MRI images and Prostate Imaging Reporting & Data System (PI-RADS) scoring of the prostate.
Personalized treatment strategies based on non-invasive biomarkers have potential to improve patient management in patients with newly diagnosed glioblastoma (GBM). The residual tumour burden after surgery in GBM patients is a prognostic imaging biomarker. However, in clinical patient management, its assessment is a manual and time-consuming process that is at risk of inter-rater variability.
View Article and Find Full Text PDFClin Infect Dis
August 2022
Hybrid imaging with positron emission tomography (PET) in combination with computer tomography (CT) is a well-established diagnostic tool in oncological staging and restaging. The combination of PET with magnetic resonance imaging (MRI) as a clinical scanner was introduced approximately 10 years ago. Although MRI provides superb soft tissue contrast and functional information without the radiation exposure of CT, PET-MRI is not as widely introduced in oncologic imaging as PET-CT.
View Article and Find Full Text PDFClin Infect Dis
August 2022
Objective: To assess the feasibility of performing dose measurements in the target (prostate) and an adjacent organ at risk (rectum) using polymer dosimetry gel and thermoluminescence detectors (TLDs) in an anthropomorphic, deformable, and multimodal pelvis phantom (ADAM PETer).
Methods: The 3D printed prostate organ surrogate of the ADAM PETer phantom was filled with polymer dosimetry gel. Nine TLD600 (LiF:Mg,Ti) were installed in 3 × 3 rows on a specifically designed 3D-printed TLD holder.
Background: This study prospectively assessed the diagnostic capacity of dynamic carbon-11 methionine (C-11 MET) positron-emission tomography (PET)/computed tomography for the diagnosis of pathologies in patients with primary unknown musculoskeletal lesions (MSLs). In total, 13 patients with MSLs underwent dynamic scans (5-10 [phase 1], 10-15 [phase 2], 15-20 [phase 3], 20-25 [phase 4], 25-30 [phase 5], and 30-35 [phase 6] min post-injection of C-11 MET). We statistically compared the maximum standardised uptake values (SUVmax) and corresponding retention index for dynamic scans (RI-SUV) for five benign MSLs (BMSLs), five primary malignant musculoskeletal tumours (PMMSTs), four metastatic musculoskeletal tumours (MMSTs), and three malignant lymphoma (ML) cases and explored their diagnostic capacities using receiver operating characteristic (ROC) curve analyses.
View Article and Find Full Text PDFWe aimed to assess the differential diagnostic efficacy of dynamic F-18 fluorodeoxyglucose (FDG) positron emission tomography / computed tomography (PET / CT) and to evaluate the appropriate scan timings for diagnosis of musculoskeletal lesions (MSLs). Dynamic scans (5-15 [phase 1], 15-25 [phase 2], and 25-35 [phase 3] min after F-18 FDG injection) and dual-time-point scans (1 and 2 h after injection) were acquired for 23 MSLs [4 benign MSLs (BMSLs). 10 primary malignant musculoskeletal tumors (PMMSTs), and 9 metastatic musculoskeletal tumors (MMSTs)].
View Article and Find Full Text PDFPurpose: This prospective trial investigates the association of time to recurrence (TTR) in glioblastoma with [C]methionine (MET) tracer uptake before postoperative radiochemotherapy (RCT) aiming to guide radiotherapy boost regions.
Experimental Design: Between 2013 and 2016, 102 patients with glioblastoma were recruited. RCT was performed with concurrent and adjuvant temozolomide to a total dose of 60 Gy.
Objective: To develop an anthropomorphic, deformable and multimodal pelvis phantom with positron emission tomography extension for radiotherapy (ADAM PETer).
Methods: The design of ADAM PETer was based on our previous pelvis phantom (ADAM) and extended for compatibility with PET and use in 3T magnetic resonance imaging (MRI). The formerly manually manufactured silicon organ surrogates were replaced by three-dimensional (3D) printed organ shells.
Clinical/methodical Issue: Optimizing radiotherapy demands precise delineation of the target structure, not only before but also during the course of radiotherapy.
Standard Radiological Methods: For many years, planning of external radiation treatment planning has been based on computer tomography data.
Methodological Innovations: With the advent of image-guided radiotherapy (IGRT), magnetic resonance imaging (MRI) and functional hybrid imaging are increasingly being integrated into radiation treatment planning.
Objective: To implement computed tomography (CT)-based attenuation maps of radiotherapy (RT) positioning hardware and radiofrequency (RF) coils to enable hybrid positron emission tomography/magnetic resonance imaging (PET/MRI)-based RT treatment planning.
Materials And Methods: The RT positioning hardware consisted of a flat RT table overlay, coil holders for abdominal scans, coil holders for head and neck scans and an MRI compatible hip and leg immobilization device. CT images of each hardware element were acquired on a CT scanner.
Background And Purpose: Radiotherapy is a standard treatment option for high-grade gliomas. Brain atrophy has previously been associated with radiotherapy. The goal of this study was to investigate dose dependent cerebellar atrophy using prospective, longitudinal MR data from adult glioma patients who received radiotherapy.
View Article and Find Full Text PDFGenes Chromosomes Cancer
October 2020
Gastrointestinal stromal tumors (GISTs) are the most frequent mesenchymal tumors of the gastrointestinal tract. Inactivating mutations or epigenetic deregulation of succinate dehydrogenase complex (SDH) genes are considered defining features of a subset of GIST occurring in the stomach. Based on comprehensive molecular profiling and biochemical analysis within a precision oncology program, we identified hallmarks of SDH deficiency (germline SDHB-inactivating mutation accompanied by somatic loss of heterozygosity, lack of SDHB expression, global DNA hypermethylation, and elevated succinate/fumarate ratio) in a 40-year-old woman with undifferentiated gastric spindle cell sarcoma that did not meet the diagnostic criteria for other mesenchymal tumors of the stomach, including GIST.
View Article and Find Full Text PDFAlthough olfactory dysfunction is one of the most well-established prodromal symptoms in Parkinson's disease (PD), its correlation with clinical disease progression or dopaminergic dysfunction still remains unclear. We here evaluated the association of striatal dopamine metabolism and olfactory function in a homogenous cohort of 30 patients with early untreated de novo PD. Striatal dopamine metabolism was assessed by the extended Fluorodopa PET scanning protocol to measure Fluorodopa uptake (K) and the effective dopamine distribution volume ratio (EDVR) as the inverse of dopamine turnover.
View Article and Find Full Text PDFWe previously reported that L-DOPA effects on reward-based decision-making in a randomized, placebo-controlled, double-blind, crossover study were consistent with an inverted U-shaped function whereby both low and high extremes of dopamine signaling are associated with high-impulsive choice. To test this hypothesis, we performed [F]DOPA positron emission tomography in 60 of the 87 participants in that study, and measured the effective distribution volume ratio (EDVR) of [F]DOPA influx rate to [F]dopamine washout rate, an index of presynaptic dopaminergic function. Participants with higher baseline EDVR self-reported lower impulsivity, and discounted rewards as a function of delay more strongly after receiving L-DOPA, whereas the opposite was detected for those with lower baseline EDVR.
View Article and Find Full Text PDFBackground And Objective: To investigate the predictive value of striatal dopamine turnover in patients with de novo Parkinson's disease (PD) for later occurrence of major non-motor health outcomes.
Methods: This retrospective, observer-blinded cohort study followed up 29 patients with de novo PD for a median of 10.7 years, who completed 18Fluorodopa PET imaging to measure striatal effective distribution volume ratio (EDVR, inverse of dopamine turnover) prior to antiparkinsonian treatment.
Objective: The objective of this study was to evaluate the effects of common functional polymorphisms in genes involved in dopamine metabolism on striatal dopamine turnover in de novo Parkinson's disease (PD).
Methods: This was an observer-blinded cohort study investigating effects of common functional polymorphisms in dopa decarboxylase (DDC, rs921451), monoamine oxidase B (MAOB; rs1799836), catechol-O-methyltransferase (COMT, rs4680), and dopamine transporter/solute carrier family 6 member 3 (DAT/SLC6A3, variable number tandem repeats) genes on F-fluorodopa uptake and an effective distribution volume ratio (inverse of dopamine turnover) measured by F-fluorodopa PET in 28 untreated PD patients.
Results: Patients carrying the MAOB genotype (low/intermediate enzyme activity) had a lower dopamine turnover in the putamen (higher mean effective distribution volume ratio) when compared with patients with MAOB genotype (high enzyme activity).
The original version of this article, published on 6 July 2018, unfortunately contained a mistake.
View Article and Find Full Text PDFObjectives: To determine the value of F-FDG-PET/MRI in the diagnosis and management of patients with pelvic recurrence of rectal cancer.
Methods: Forty-four patients (16 women, 28 men) with a history of rectal cancer who received FDG-PET/MRI between June 2011 and February 2017 at our institution were retrospectively enrolled. Three patients received two FDG-PET/MRIs; thus a total of 47 examinations were included.
The integration of data from positron-emission-tomography, combined with computed tomography as positron emission tomography computed tomography (PET/CT) or combined with magnet resonance imaging as PET/MRI, into radiation treatment planning of prostate cancer is gaining higher impact with the development of more sensitive and specific radioligands. The classic PET-tracer for prostate cancer imaging are [11C]choline and [11C]acetate, which are currently outperformed by ligands binding to the prostate-specific-membrane-antigen (PSMA). [68Ga]PSMA-11, which is the most frequently applied tracer, has shown to detect lymph node metastases, local recurrences, distant metastases and intraprostatic foci with high sensitivity, even at relatively low PSA levels.
View Article and Find Full Text PDFEur Neuropsychopharmacol
June 2018
Existing literature suggests that striatal dopamine (DA) tone may be altered in individuals with higher body mass index (BMI), but evidence accrued so far only offers an incomplete view of their relationship. Here, we characterized striatal DA tone using more comprehensive measures within a larger sample than previously reported. In addition, we explored if there was a relationship between striatal DA tone and disinhibited eating.
View Article and Find Full Text PDFClinical/methodical Issue: Magnet resonance imaging (MRI) is an excellent anatomical reference method for the combination with positron emission tomography (PET). But MRI does not produce data, which can be directly used for attenuation correction of PET data, potentially compromising quantitative accuracy of PET.
Standard Radiological Methods: Hybrid-positron emission tomography/computed tomography (PET/CT) is an established standard diagnostic tool, particularly for staging and restaging in oncology.
Background And Purpose: To compare the structural and hemodynamic changes of healthy brain tissue in the cerebral hemisphere contralateral to the tumor following photon and proton radiochemotherapy.
Materials And Methods: Sixty-seven patients (54.9 ±14.
Objective: To assess the feasibility of positron emission tomography/magnetic resonance imaging (PET/MR) with 18F-fluordeoxyglucose (FDG) for initial staging of sarcoma.
Materials And Methods: Twenty-nine patients with sarcoma were included in this study. Weighted kappa (κ) was used to assess the agreement between PET/MR and conventional imaging (CT and MR).