HIGH-FIELD CLOSED MRI 
A closed MRI machine gives the Radiologist the best image because the magnet encircles the entire body and is generally much stronger than the magnets in open MRI machines; however, a closed MRI machine can make some patients feel uncomfortable, because the enclosed area ("tube") is somewhat narrow and small. (The patient lies down on a moveable examination table, and is slowly inserted into the "tube," either feet first or head first, depending on what area of the body needs to be examined/imaged.) The patient is instructed to lie still, and the inside of the scanner is well lit and has its own ventilation. The technologist (person taking the MRI scanned image) can see and communicate with the patient (using a two-way intercom system) during the entire procedure, and the patient can also communicate at all times with the technologist. A closed MRI machine can only take a patient weighing up to 300 pounds.
LOW-FIELD OR MID-FIELD OPEN MRI
An open MRI machine is open on one side, and can make the patient feel more comfortable. The magnet strength is not as strong as a closed MRI machine, and an open MRI machine can take patients up to 450 pounds. The Camp Lowell Imaging Center now offers our new Altaire mid-field open MRI machine (see picture).
HIGH-FIELD ESPREE OPEN MRI
An Espree open MRI machine appears to be a closed MRI machine; however, it has a wide opening ("tube") - of more than two feet in diameter. The Espree open MRI machine generally has a stronger magnet than the open MRI machine, but not as strong as a closed MRI machine.