Rapid urine dilution to improve pelvic imaging in bone scanning

A significant reduction in the contribution of bladder radioactivity to total counts seen on the anterior pelvic view of a bone scintiscan can be effected by the administration of 16 to 32 oz of water given immediately after the initial series of bone images (3 hr delayed) with a repeat pelvic spot view immediately thereafter. A mean reduction of bladder radioactivity from 29% of total pelvic counts to 7.5% was facilitated using this modification of our routine bone imaging protocol. This sample, rapid dilution technique improved image quality in each of a total of 11 arbitrarily selected patients evaluated by bone scintigraphy, without increasing total scan time or resulting in any adverse or untoward effects