Q. Sometimes my doctor orders an M.R.I., sometimes a CAT scan or an ultrasound. If one is best, why not just order it every time?

A. The rationale for selecting an imaging test is complicated, but some general principles can be helpful.

Read on:

https://www.nytimes.com/2018/11/23/well/live/which-type-of-medical-scan-is-right-for-me.html

By Richard Klasco, M.D.
Nov. 23, 2018
The New York Times