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Purpose: To evaluate the impact of video sequences (cine-loops) on the interobserver agreement (IOA) using risk stratification systems (RSSs) for thyroid nodules (TNs). Methods: Twenty TNs were randomly selected from a large database and evaluated by twelve experienced observers using five different RSSs (Kwak-, ACR-, EU-, Korean-TIRADS, ATA Guidelines). In the first step, the evaluation was conducted based on static ultrasound (US) images in two planes (“static”). Six months later, these cases were reevaluated by the same observers using video sequences in two planes (“cine-loops”). Fleiss’ kappa (κ) was calculated for the IOA analyses. Results: IOA on static was moderate with κ values of 0.46, 0.42, 0.40, 0.45, and 0.38 for the Kwak-, ACR-, EU-, Korean-TIRADS, and ATA Guidelines, respectively, while the IOA on cine-loops was fair with κ values of 0.41, 0.38, 0.37, 0.36, and 0.34 for the Kwak-, ACR-, EU-, Korean-TIRADS, and ATA Guidelines, respectively. The overall IOA was superior in static images versus cine-loops (p = 0.024). Among other findings, the subgroup analyses (related to age, gender, US certificates, number of thyroid US per week, and RSSs experience) particularly showed that the experience of the observers in using RSSs had a significant influence on the IOA. Conclusions: The overall IOA (all twelve observers and all five RSSs) was superior on static US images in comparison to cine-loops. Furthermore, the overall IOA of the five US features revealed superior κ values of the static images over cine-loops. However, this impact was significantly lower when the observers were highly experienced in the use of US RSSs of TNs.

(1) Background: PSMA ligand PET/CT is increasingly important for diagnostics of prostate cancer and other tumor diseases. In particular, the radiopharmaceutical [68Ga]Ga-PSMA-11 is widely used. Besides its tumor-specific binding, the uptake within the kidneys is dominant and seems to visualize the renal cortex specifically. Kidney diseases may alter the uptake of radiopharmaceuticals. Therefore, the correlation between renal uptake in PET/CT imaging and renal function should be investigated. (2) Methods: A group of 103 male patients were retrospectively evaluated for eGFR according to the CKD-EPI equation, tracer uptake intensity (SUVmax, SUVpeak, SUVmean), the molecular volume of the renal cortex, morphological kidney size, and total renal uptake. Manual and three different computer-assisted contouring methods (thresholds at 50% of SUVmax, 30% of SUVmax, and absolute SUV of 20) were used for measurements. Correlations between parameters were calculated using linear regression models. (3) Results: Renal SUVmax, SUVpeak, and SUVmean do not correlate with eGFR for manual or computer-assisted measurements. In contrast, molecular cortex volume shows a moderate correlation with eGFR (R2 = 0.231, p < 0.001), superior to morphological kidney size. A contouring threshold of 30% of SUVmax outperformed the other settings for renal cortex volume and total renal uptake. (4) Conclusions: Renal uptake of [68Ga]Ga-PSMA-11 cannot predict eGFR, but the functional renal cortex can be quantified by PET/CT imaging.