The dosage of technicium-99m for a lung scan is 20. µCi/kg of body mass. How many millicuries of technicium-99m should be given to a person weighing 50. kg (1 mCi = 1000 µCi)

Verified step by step guidance

1. Step 1: Understand the problem. The dosage of technicium-99m is given as 20 µCi/kg of body mass, and the person weighs 50 kg. The goal is to calculate the total dosage in millicuries (mCi). Note that 1 mCi = 1000 µCi.
2. Step 2: Calculate the total dosage in microcuries (µCi) by multiplying the dosage per kilogram by the person's weight. Use the formula: $\mathrm{Total}=\mathrm{Dosage}\times \mathrm{Weight}$, where Dosage = 20 µCi/kg and Weight = 50 kg.
3. Step 3: Convert the total dosage from microcuries (µCi) to millicuries (mCi). Use the conversion factor: $1\mathrm{mCi}=1000\mathrm{\mu Ci}$. Divide the total dosage in µCi by 1000 to get the value in mCi.
4. Step 4: Write the final expression for the dosage in mCi: $\mathrm{Dosage}=\frac{\mathrm{Total}\mathrm{\mu Ci}}{1000}$. Substitute the calculated value from Step 2 into this formula.
5. Step 5: Verify the units and ensure the final answer is expressed in millicuries (mCi). Double-check the calculations for accuracy and confirm the result aligns with the problem requirements.

Key Concepts

Radioactive Dosage Calculation

Radioactive dosage calculation involves determining the appropriate amount of a radioactive substance to administer based on a patient's body mass. In this case, the dosage of technetium-99m is given in microcuries per kilogram, requiring multiplication by the patient's weight to find the total dosage in microcuries.

Unit Conversion

Unit conversion is the process of changing a quantity expressed in one unit to another unit. In this scenario, it is essential to convert microcuries (µCi) to millicuries (mCi) since the final answer is required in millicuries. Understanding the relationship between these units (1 mCi = 1000 µCi) is crucial for accurate calculations.

Technetium-99m

Technetium-99m is a widely used radioactive isotope in medical imaging, particularly in nuclear medicine for diagnostic scans. Its properties allow for effective imaging of various organs, including the lungs, making it essential to understand its dosage and safety in clinical applications. Knowledge of its half-life and biological behavior is also important for ensuring patient safety.