The magnetic field in MRI is measured in

Tesla =magnetic fieldHounsfield units =CT numberMHz = To denote probe frequency in USGThe units of magnetic field strength are Gauss and Tesla. Tesla was the father of alternating current and Gauss was German mathematician. 1Tesla = 10 KG = 10, 000 Gauss Gauss is a measure of low magnetic field strength. Eah's magnetic field strength is approximately 0.6 G. MR systems used for clinical purpose have the strength ranging from 0.2 to 3 Tesla. Field strengths higher than 3T are used for research purposes. SNR and resolution increase with the field strength. Advanced MR applications like Spectroscopy, functional MRI, cardiac MR are possible only on higher field strengths like 1.5 T and above.(Ref: MRI made Easy by Chavan; 2nd Edition, Page No 23)