Ga-DOTATOC uptake in the thoracic aorta exhibited a significant correlation with cardiovascular risk factors, which suggests the feasibility of Ga-DOTATOC PET for vulnerable plaque imaging, with a simple measurement of the single VOI method that is comparable to the multi-sample ROI-based approach.

Planar scintigraphy using Tc-99m pertechnetate is useful for snapshot evaluation of hot thyroid nodules, which are pathologically follicular adenoma and seldom, if ever, malignant. The autonomy of the hot nodules has been demonstrated by the presence of thyroid-stimulating hormone-dependent extra-nodular thyroid tissue besides the hot nodules. Here, we present two cases of hot thyroid nodules in patients who underwent quantitative single-photon emission computed tomography/computed tomography (SPECT/CT). In addition to the nodules, contralateral normal thyroid parenchyma was evaluated based on standardized uptake values. One patient had a traditional follicular adenoma suppressing other thyroid tissue, whereas the other patient seemed to have a nodule erupting from underlying hyperfunctioning, not suppressed, thyroid tissue. This novel approach using quantitative SPECT/CT unveils a new pathology of hot thyroid nodule that does not suppress, but coincides with hyperfunctioning thyroid tissue.

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Purpose Although 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is a standard imaging modality for response evaluation in FDG-avid lymphoma, there is a controversy using FDG PET in indolent lymphoma. The purpose of this study was to investigate the effectiveness of quantitative indexes on FDG PET in response evaluation of the indolent lymphoma. Methods Fifty-seven indolent lymphoma patients who completed chemotherapy were retrospectively enrolled. FDG PET/ computed tomography (CT) scans were performed at baseline, interim, and end of treatment (EOT). Response was determined by Lugano classification, and progression-free survival (PFS) by follow-up data. Maximum standardized uptake value (SUV max ), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured in the single hottest lesion (target A) or five hottest lesions (target B). Their efficacies regarding response evaluation and PFS prediction were evaluated. Results On EOT PET, SUV max , and MTVof both targets were well associated with visual analysis. Changes between initial and EOT PET were not significantly different between CR and non-CR groups. On interim PET, SUV max , and %ΔSUV max in both targets were significantly different between CR and non-CR groups. For prediction of PFS, most tested indexes were significant on EOT and interim PET, with SUV max being the most significant prognostic factor. Conclusion Quantitative indexes of FDG PET are well associated with Lugano classification in indolent lymphoma. SUV max measured in the single hottest lesion can be effective in response evaluation and prognosis prediction on interim and EOT PET.

Background: Elevated metabolic activity of amygdala is known to be related to atherosclerotic cardiovascular event by increasing inflammatory cell production from bone marrow. We tried to identify the factors of metabolic activity in the amygdala, vertebrae, liver, spleen, and internal carotid artery related to the future vascular events after stroke. Methods: A total of 110 patients with acute stroke were included (72±10 years of age, 39% women) and underwent whole-body 18 F-fluorodeoxyglucose (FDG) positron emission tomography between August 1, 2015 and February 28, 2020. We compared the FDG uptake in the amygdala, vertebrae, liver, spleen, and internal carotid artery between patients with and without recurrent vascular event. Cox proportional hazards model was used to identify factors related to recurrent stroke and vascular event. Results: During the median follow-up period of 18 months, 22 patients experienced vascular events, including 15 stroke recurrence. Patients with recurred vascular event had a significantly higher FDG uptake in the amygdala and vertebrae than those without. The Cox proportional hazard model including diabetes, renal function, and carotid stenosis showed that a higher FDG uptake in the amygdala was independently associated with total vascular events (hazard ratio, 3.11 [95% CI, 1.11–8.70]) and higher FDG uptake in the vertebrae with stroke recurrence (hazard ratio, 4.94 [95% CI, 1.29–18.9]). Conclusions: The increased metabolic activities of the vertebrae and amygdala are related to future vascular event among stroke survivors.