Adrenal scintigraphy with 75Se selenonorcholestenol: a review.

We have reviewed 58 patients on whom adrenal scintigraphy has been performed using 75Se selenonorcholestenol. For 15 patients whose adrenal function was biochemically normal, the upper limit of normal of the 7 day adrenal uptake test was 0.45%, considerably higher than the generally accepted value of 0.3%. There is evidence from this group of patients that stress and obesity might account for uptakes in the range 0.3-0.45%. The sensitivity of the uptake test is poor, with 7 out of 23 patients with Cushing's syndrome having uptakes within the normal range. Scintigraphy of such patients may still be useful in differentiating between unilateral and bilateral adrenal involvement.