Reduction of Radiation Exposure in Adrenal Vein Sampling: Impact of the Rapid Cortisol Assay.

Abstract

To determine radiation exposure associated with adrenal vein sampling and its reduction by implementing the rapid cortisol assay and modification of the sampling protocol. A single-center retrospective study of adrenal vein sampling performed between August 2009 and March 2020 revealed data from 151 procedures. Three subgroups were determined. In group I, a sampling protocol including sampling from the renal veins without the rapid cortisol assay was applied. In group II, blood was sampled using the same protocol but applying the rapid cortisol assay. In group III, a modified sampling protocol was used, in which the additional sampling from the renal veins was dispensed with, while the rapid cortisol assay was retained. Primary endpoints were radiation exposure parameters with dose area product, fluoroscopy time, and effective dose. As secondary endpoints, procedural data including technical success, lateralization, the correlation between patient BMI and radiation exposure, and concordance of lateralization with cross-sectional imaging were investigated. Furthermore, the correlation of aldosterone-cortisol ratios between the adrenal and ipsilateral renal vein was calculated to assess the benefit of sampling from the renal veins. For all procedures performed in the study collective, the median dose area product was 60.01 Gy*cm2 (5.71-789.31), the median fluoroscopy time was 14.90 min (3.27-80.90), and the calculated median effective dose was 12.60 mSv (1.20-165.76). Significant differences in radiation exposure parameters between the study subgroups could be revealed. Dose area product resulted in reductions of 57.94 % after implementation of the rapid cortisol assay and a further 40.44 % after revision of the sampling protocol. Fluoroscopy time was reduced by 40.48 % after integration of the rapid cortisol assay and a further 40.47 % after protocol refinement. Radiation doses were increased in cases of resampling (dose area product 51.31 vs. 118.11 Gy*cm2, fluoroscopy time of 12.48 vs. 28.70 min). A strong correlation between patient BMI and procedural dose area product could be found. After the introduction of the rapid cortisol assay, successive improvement of the technical success rate could be found (33.33 % in group I, 90.22 % in group II and 92.11 % in group III). The correlation of aldosterone-cortisol ratios between adrenal and renal veins was poor. The introduction of the rapid cortisol assay significantly decreased the radiation exposure and increased the technical success rate. Renal vein sampling did not provide further benefit in the evaluation of primary aldosteronism subtype and its omission resulted in a further reduction of radiation dose. · The rapid cortisol assay significantly reduces the procedure-related radiation dose in adrenal vein sampling and increases the procedural technical success.. · Since additional sampling from the renal veins offers no further diagnostic benefit, a refinement of the sampling protocol can enable a further reduction of radiation dose.. · Resampling, technical unsuccessful procedures, and higher patients' BMI are associated with higher radiation exposures.. · Augustin A, Dalla Torre G, Fuss CT et al. Reduction of Radiation Exposure in Adrenal Vein Sampling: Impact of the Rapid Cortisol Assay. Fortschr Röntgenstr 2021; 193: 1392 - 1402.