Adrenal_washout v.1
The Adrenal washout calculator determines absolute and relative washout based on pre and post contrast and 15 minutes delayed CT scans.
To calculate the absolute and relative washout.
Use to calculate the absolute and relative washout. Formulas: Absolute Washout = 100 x (Post contrast HU – Delayed phase HU) / (Post contrast HU – Pre contrast HU) Relative Washout = 100 x (Post contrast HU – Delayed phase HU) / Post contrast HU Interpretation: Absolute washout ≥ 60% is strongly suggestive of adrenal adenoma. Relative washout ≥ 40% is strongly suggestive of adrenal adenoma. Regardless of absolute or relative washout, if pre-contrast attenuation is low (<10 HU), then adenoma should be further investigated.
Boland GW, Lee MJ, Gazelle GS, Halpern EF, McNicholas MM, Mueller PR. Characterization of adrenal masses using unenhanced CT: an analysis of the CT literature. AJR Am J Roentgenol. 1998 Jul;171(1):201-4. doi: 10.2214/ajr.171.1.9648789. PMID: 9648789.
openEHR-EHR-OBSERVATION.adrenal_washout
