1. What is a DLP Calculator?

Definition: This calculator computes the Dose Length Product (DLP) in CT scans by multiplying the CTDIvol by the scan length.

Purpose: It helps radiologists and medical professionals estimate patient radiation exposure during CT examinations.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( DLP \) — Dose Length Product (mGy·cm)
• \( CTDI_{vol} \) — Volume CT Dose Index (mGy)
• \( Scan\ Length \) — Length of the scanned area (cm)

Explanation: The CTDIvol (a standardized dose measurement) is multiplied by the scan length to get the total radiation dose for the examination.

3. Importance of DLP Calculation

Details: DLP provides a standardized way to compare radiation doses between different CT protocols and helps in patient dose monitoring and optimization.

4. Using the Calculator

Tips: Enter the CTDIvol (found in the CT dose report) in mGy and the scan length in cm. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical CTDIvol value?
A: CTDIvol varies by exam type: ~10-20 mGy for head CT, ~5-15 mGy for chest CT, depending on protocol and equipment.

Q2: How does DLP relate to effective dose?
A: Effective dose (in mSv) can be estimated by multiplying DLP by a tissue-specific conversion factor.

Q3: Why is DLP important in CT?
A: DLP allows comparison of radiation doses between different CT exams and helps track patient exposure over time.

Q4: Where can I find CTDIvol on my scanner?
A: CTDIvol is automatically displayed on the dose report generated by the CT scanner for each examination.

Q5: Does DLP account for patient size?
A: No, DLP is a machine output metric. For patient-specific dose, size-specific dose estimate (SSDE) may be more appropriate.