washout curve
Time-activity curve showing radiotracer clearance from normal versus abnormal parathyroid tissue on nuclear imaging.
Full Definition
The washout curve in parathyroid nuclear medicine imaging represents the rate of radiotracer clearance from parathyroid tissue over time, typically measured during sestamibi scanning. Normal parathyroid tissue shows rapid washout of the radiotracer, while hyperfunctioning parathyroid adenomas demonstrate delayed washout or retention. This differential washout pattern helps distinguish abnormal parathyroid tissue from normal thyroid tissue and other structures. The curve is analyzed by comparing early and delayed imaging phases, usually at 20 minutes and 2-3 hours post-injection.
Usage
Usage note: May be written as one word 'washout' or hyphenated 'wash-out' depending on institutional preference.
In Context
- "The washout curve demonstrated delayed clearance consistent with parathyroid adenoma." — nuclear medicine report
- "Analysis of the washout curve helped differentiate the adenoma from thyroid tissue." — imaging interpretation