This is one article title that caught my attention instantly – “Why 1.5T MRI is Leading the Pack”.
Perfectly valid question, and my answer to it was – ‘because its cheaper (than 3T) and gets the job done”, well apparently, I was only half correct.
According to Alan R. Moody (radiologist in chief, department of diagnostic imaging, Sunnybrook Health Sciences Centre in Toronto), even though 3T systems can scan faster or at higher resolution than 1.5T scanners, the proven, reliable imaging strength and quality of 1.5T are what many medical imaging professionals continue to compare everything else to.
“While 3T is excellent for neurological and musculoskeletal applications, it lags behind 1.5T in abdominal imaging and cardiac imaging, which are areas in which “we tend to put the majority of our work for the 1.5T,” he notes. Another challenge of higher strength magnets is the interaction with metal implants such as stents, aneurysm clips and even prosthetic devices. With 1.5T, patients who have these safety concerns are not an issue and can be imaged without an increase in metal artifact.
Another limitation of 3T, and thus a benefit of 1.5T, is related to its energy deposition. 3T might enable faster and higher resolution imaging, however, the restriction is in how much energy can be put back into the patient. “With 3T you have to ease back on the throttle, and you potentially lose some of the advantages you had of ramping up to that field strength in the first place,” Moody says, who adds that there seems to be a slight plateauing of that linear progression of the low field strength. Instead of racing to the next level in magnet strength, the imaging community has hit a plateau, staying strong with 1.5T MRI for its applicability across imaging applications.”
I guess bigger isn’t always better 🙂