Adaptation of a standard low-field (0.3-T) system to the operating room: focus on pituitary adenomas

Intraoperative MRI (iMRI) is a reliable and safe tool to monitor the extent of resection and to avoid complications in the transsphenoidal surgical approach for pituitary tumors. The best indication for its application in transsphenoidal surgery is for patients with pituitary macroadenomas with suprasellar extension. The low-field 0.3-T magnet has a diagnostic imaging quality that provides surgeons with good intraoperative detail of the anatomic relations in the sellar region. In our experience, iMRI provided a distinct benefit in planned subtotal resection for invasive macroadenomas that compress the optic chiasm and in planned gross total resection for noninvasive tumors. The iMRI design adopted at our center includes important features, such as the use of ferromagnetic surgical instruments, elimination of patient transportation, and capability as a shared resource, that allow multipurpose diagnostic use and increased cost-effectiveness.