If the thermal index (TI) equals 1, which statement is true?

If the thermal index (TI) equals 1, which statement is true?

• A. The output level is high enough that temperature could increase as much as 1 degree C if the transducer were held stationary.
• B. The patient’s temperature has increased 1 degree C as a result of the ultrasound scan.
• C. The patient’s temperature has increased 2 degrees C as a result of the ultrasound scan.
• D. You must limit your scanning to 1 minute.

Answer: (A)

Thermal Index (TI) reflects how much tissue temperature could rise from the ultrasound exposure. It’s an estimate, not a measured temperature. When TI is 1, it means the ultrasound could increase tissue temperature by about 1°C if the transducer were held stationary and emitting continuously. So this option correctly interprets TI as a potential rise under those defined conditions. The other statements describe actual temperature increases or a time limit, which TI does not assert. The actual rise depends on duration, motion, and settings, and TI provides a cautionary guideline rather than a guaranteed change or a required time restriction.

Thermal Index (TI) reflects how much tissue temperature could rise from the ultrasound exposure. It’s an estimate, not a measured temperature. When TI is 1, it means the ultrasound could increase tissue temperature by about 1°C if the transducer were held stationary and emitting continuously.

So this option correctly interprets TI as a potential rise under those defined conditions. The other statements describe actual temperature increases or a time limit, which TI does not assert. The actual rise depends on duration, motion, and settings, and TI provides a cautionary guideline rather than a guaranteed change or a required time restriction.