The presence of a cochlear implant (CI) used to be an absolute contraindication for MRI unless the internal magnet was surgically removed prior to scanning. More recently implant manufacturers produced devices labelled as MR conditional. The main complications in MRI arise from the magnetic force and torque on the internal magnet from B0. To address … More Are cochlear implants MR conditional?
A fascinating ebook/website has been compiled by Graeme Bydder and Martyn Paley outlining the history of the development of MR imaging and spectroscopy in the UK. There are personal accounts from some of the pioneers including the late Ian Young and Bill Edelstein and many others. There are also obituaries for international researchers including Nobel … More History of MR in the UK
Listed below are some international and national (esp. UK and Australasia) MR safety standards and professional guidance documents. Reproduced from Essentials of MRI Safety. They are listed alphabetically. ACR Guidance Document on MR Safe Practices: 2013, American College of Radiology Expert panel on MR Safety Kanal et al. Magn. Reson. Imag. 37:501-530. Link: https://www.acr.org/Clinical-Resources/Radiology-Safety/MR-Safety Status: US-based … More MRI Safety Standards and Guidance
MR signal and contrast calculator (SE) The MR signal and contrast calculator lets you choose two tissue T1 and T2 whilst manipulating the scanner parameters: TR and TE to show the signal, contrast and relative contrast to noise ratio (CNR). Use the calculator to explore the weightings below. MR gradient echo signal and contrast calculator … More MR signal and contrast calculators
Gradient echo (GE, GRE, FLASH, SPGR, T1-FFE, FE) is one of the hardest elements of MRI to understand. Image signal and contrast in spoiled gradient echo depends upon three user-selected parameters: Flip angle <90º TR – repetition time, typically > 10 ms TE – echo time, typically > 2 ms Signal and contrast also depend … More Gradient echo signal and contrast