[en] To evaluate the frequency of visualization of the right adrenal vein (RAV) on dual adrenal venous phase multi-detector computed tomography (MDCT) in patients with primary aldosteronism. Images of contrast-enhanced dual adrenal venous phase MDCT (45- and 55-second delays) in 90 patients with primary aldosteronism who underwent adrenal venous sampling were retrospectively evaluated. The degree of RAV visualization on each phase image was evaluated by two radiologists using a five-point scale and RAV visualization rates were estimated. The RAV visualization rates on the first- and second-phase images were 89 % and 91 % by radiologist A, and 93 % and 90 % by radiologist B, respectively. No significant differences in the score of RAV visualization were observed between the first- and second-phase images by the two readers (P = 0.164 and P = 0.06). The kappa values for inter-observer agreement of RAV visualization on the first- and second-phase images were 0.57 and 0.46, respectively. The consensual RAV visualization rates on the first- and second-phase images were 91 % and 92 %, respectively. The overall RAV visualization rate by using both phase images was 98 %. Dual adrenal venous phase MDCT can visualize the RAV in almost all patients with primary aldosteronism. (orig.)