June 16, 2021 — A novel positron emission tomography (PET) radiotracer has been shown to effectively measure increases in brain tau—a distinguishing characteristic of...
News from the Society of Nuclear Medicine and Molecular Imaging (SNMMI) and its annual meeting. It is the primary medical society for nuclear imaging (PET and SPECT) and nuclear medicine treatments for cancer.
Figure 1. Tau accumulation over one year measured in composite A) mesial temporal ROI; and B) temporoparietal ROI in cognitively unimpaired participants (blue) and cognitively impaired participants (red). The CI group included participants with clinical mild cognitive impairment and dementia. Higher rates of tau accumulation were observed in participants on the AD continuum (CU Aβ+ve and CI Aβ+ve). Participants with the highest baseline tau and rates of tau accumulation were younger and more likely to be CI Aβ+ve. Image courtesy of SNMMI
Figure 1. A: COVID-19-related spatial covariance pattern of cerebral glucose metabolism overlaid onto an MRI template. Voxels with negative region weights are color-coded in cool colors, and regions with positive region weights in hot colors. B: Association between the expression of COVID-19-related covariance pattern and the Montreal Cognitive Assessment (MoCA) score adjusted for years of education. Each dot represents individual patient. C: Results of a statistical parametric mapping analysis. Upper row illustrates regions that show significant increases of normalized FDG uptake in COVID-19 patients at 6-months follow-up compared to the subacute stage (paired t test, p < 0.01, false discovery rate-corrected). Bottom row depicts regions that still show significant decreases of normalized FDG uptake in COVID-19 patients at 6-months follow-up compared to the age-matched control cohort at an exploratory statistical threshold (two-sample t test, p < 0.005). Image Credit: G Blazhenets et al., Department of Nuclear Medicine, Medical Center – University of Freiburg, Faculty of Medicine, University of Freiburg
Result of the Hoffman brain phantom study. Top row: same PET slice reconstructed with A) 2mm static OSEM, B) 1mm static OSEM, C) proposed SR method and D) corresponding CT slice (note that the CT image can be treated as a high-resolution reference). Middle row: zoom on region of interest for corresponding images. Bottom row: Line profiles for corresponding data. Image created by Y Chemli, et al., Gordon Center for Medical Imaging: Department of Radiology Massachusetts General Hospital, Harvard Medical School, Boston, MA.
A) Axial CT images through the mouse lungs at 7 and 14 days after intratracheal administration of bleomycin or saline (as a control), demonstrating increased lung fibrosis in the bleomycin group (white arrows). (B) CT attenuation histograms in Hounsfield units (HU) after lung segmentation demonstrate increased attenuation in the lungs in the bleomycin group than the control group (p <0.05), consistent with increasing fibrosis (n=3). (C) Representative axial PET/CT fusion images at 20 and 60 min demonstrating increased FAPI uptake in the lungs of the bleomycin group (white arrows) with no significant uptake in the control group (yellow arrows). (D) Time-activity curve of lung uptake ROI analysis demonstrating higher FAPI uptake in the lungs of the bleomycin group than the control (p < 0.05), 14 days after bleomycin (n=3). (E) Ex vivo biodistribution data of lung tissue demonstrating higher radiotracer uptake in the lungs of the bleomycin group than the control (n=3). *p<0.05, **p<0.01. Image created by CA Ferreira et al., University of Wisconsin-Madison, Madison, WI.
After radiosurgery concurrent with nivolumab in 59-year-old patient with melanoma BM (patient 1; Supplemental Tables 3 and 5), F-18 FET PET at follow-up 12 weeks after treatment initiation (bottom row) shows significant decrease of metabolic activity (TBRmean, ?28%) compared with baseline (top row), although MRI changes were consistent with progression according to iRANO criteria. Reduction of metabolic activity was associated with stable clinical course over 10 mo. CE = contrast-enhanced. Image created by N. Galldiks et al., Research Center Juelich, Juelich, Germany.
CXCR4-directed PET correlates with MRI-determined lymphoma lesions. Depicted are representative MR images (T1c- and FLAIR- sequences), and the corresponding CXCR4- directed PET images and fusion images (MRI-FLAIR and PET), of two patients with PCNSL and SCNSL, respectively. Images created by Department of Nuclear Medicine, School of Medicine, Technische Universität München, Munich, Germany.
Tau (blue) and amyloid (orange) distribution patterns for super-agers, normal-agers and MCI patients, when compared to a group of younger, healthy, cognitively normal, amyloid-negative individuals. Brain projections are depicted at an uncorrected significance level of p < .0001. Color bars represent the respective t-statistic. Image courtesy of Merle C. Hoenig, Institute for Neuroscience and Medicine II - Molecular Organization of the Brain, Research Center Juelich, Juelich, Germany, and Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany.
PSMA PET/CT accurately detects recurrent prostate cancer in 67-year-old man. 18F-DCFPyL-PSMA PET/CT shows extensive, intensely PSMA-avid local recurrence in prostate (bottom row; solid arrow) in keeping with the known tumor recurrence in the prostate. Right: PET shows extensive, intensely PSMA-avid local recurrence in prostate (top row; solid arrow) and a solitary bone metastasis in left rib 2 (bottom row; dotted arrow). Image courtesy of Ur Metser, et al.
Total-body dynamic 18F-FDG PET imaging with the uEXPLORER scanner allows us to monitor the spatiotemporal distribution of glucose concentration in metastatic tumors in the entire body (a). As compared to a typical clinical standardized uptake value image (b), the parametric image of FDG influx rate (Ki) can achieve higher lesion-to-background (e.g., the liver) contrast. In addition to glucose metabolism imaging by Ki, total-body dynamic PET also enables multiparametric characterization of tumors and organs using additional physiologically important parameters, for example, glucose transport rate K1 (d), across the entire body. Image courtesy of G.B. Wang, M. Parikh, L. Nardo, et al., University of California Davis, Calif.
PET/CT imaging showing uptake and retention of 86Y-NM600 (imaging agent) in immunocompetent mice bearing prostate tumors. PET imaging data was employed to estimate tumor dosimetry and prescribe an immunomodulatory 90Y-NM600 (therapy agent) injected activity. Image courtesy of R Hernandez et al., University of Wisconsin-Madison, WI.
Adult male with decades of right neck pain, discomfort and tightening following birth injury. The patient had failed multiple standard therapeutic maneuvers before presenting for 18F-FDG PET/MR imaging. Images shows abnormally elevated FDG uptake (white arrows; SUVmax = 1.2) observed in a linear pattern in the space in the posterolateral right neck, between the oblique capitis inferior and the semispinalis capitis muscles, where the greater occipital nerve resides. By comparison, the same region on the contralateral, asymptomatic side of the neck has an SUVmax = 0.7. This result encouraged a surgeon to explore the area. The surgeon ultimately found a collection of small arteries wrapped around the nerve in this location. The small arteries underwent lysis by the surgeon and the patient reported tremendous relief of symptoms. (A) Coronal thick slab MIP of 18F-FDG PET. (B) Axial LAVA FLEX MRI through the cervical spine. (C) Axial PET at the same slice as the axial MRI. (D) Fused axial PET/MRI. Image courtesy of Cipriano, et al., Stanford University, CA.
Left: Total-body PET/CT in psoriatic arthritis: multiple joints affected, shoulders, elbows, wrists, knees, ankles and small joints of the hands/feet. Arrow: left wrist; arrowhead: right wrist. Middle: Total-body PET/CT in rheumatoid arthritis: multiple joints affected, right shoulder, small joints of the left hand. Arrowhead at the 4th proximal interphalangeal joint shows classic ring-like uptake pattern. Arrow on the foot images demonstrates the hammer toe deformity besides big toe arthritis. Right: Total-body PET/CT in osteoarthritis: affected joints include the left elbow, right knee (arrow) and right big toe (arrowhead). Image courtesy of YG Abdelhafez et al., University of California Davis, Sacramento, CA.
Maximum-intensity projections, transaxial fusion, and PET images of 18F-PSMA1007 (A-C) and 68Ga-PSMA-11 (D-F) PET/CT scans of 67-y-old patient with GS 8 and PSA 4.9 ng/mL. Marked uptake is seen in urinary bladder and left ureter (arrow) on maximum-intensity projection image of 68Ga-PSMA-11 (D), as opposed to nearly negligible 18F-PSMA-1007 urinary excretion (A). Dominant lesion in left prostatic lobe is evident on both scans (arrowheads). However, second lesion is seen in right lobe only on 18F-PSMA-1007 scan (arrow in C), later verified on pathology as true malignant lesion. Images created by J. Kuten et al., Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.