Home
Radiology Guides Anatomy Physio & Path Medicine Physics Contact
ULTRASOUND-THERMAL INDEX (TI)

Physics

ULTRASOUND-THERMAL INDEX (TI)

1. The TI estimates the temperature rise in the patient.

2. There are three indices depending on the region being scanned: Soft tissue thermal index (TI S ), Bone thermal index (TI B ) for scanning through soft tissue into bone, Cranial thermal index (TI C ) for scanning through bone into soft tissue.

3. Thermal indices are pre-calculated by the manufacturer and so are a best guess only. Rule of thumb: The “real” temperature rise is ~ 2 x TI but guidelines are based on TI alone.

4. FDA states TI < 6 (except ophthalmology where it’s < 1). BMUS states TI < 3 for fetal scanning.


Avatar
REFERENCES

1. Bushberg, J. T. (2012). The essential physics of medical imaging. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins. Find it at Amazon
2. Heggie, J. C., Liddell, N. A., & Maher, K. P. (1997). Applied imaging technology. Melbourne: St. Vincents Hospital.

Ⓒ A. Manickam 2018

+ Home