Siemens wins FDA clearance for Magnetom Open MRI scanner

FDA finishes device review in four months

Medical imaging vendors are enjoying a rare burst of productivityfrom Food and Drug Administration product reviewers, who havebeen granting marketing clearance to imaging devices at a frenziedpace this year. The latest winner in the device review lotteryis Siemens Medical Systems. The German vendor received word lastmonth of FDA clearance for Magnetom Open, a 0.2-tesla scannercapable of interventional MRI procedures. The FDA's action cameonly four months after Open's 510(k) application was filed.

Magnetom Open was introduced at the Radiological Society ofNorth America meeting last year (SCAN 11/17/93). The system, whichemploys resistive magnet technology and actively shielded gradients,is shaped like a giant C-arm to give clinicians access to patients.

Siemens hopes to use Open to forge new ground in interventionalMRI, but has plans for the scanner beyond this still-emergingniche. The vendor will also market Open as a cost-effective systemthat can pay for itself with traditional MRI procedures whileclinicians explore the utility of interventional scanning. Siemensplans to set the unit's list price under $1 million.

One of Magnetom Open's beta sites will be the newly formedCenter for Interventional MRI at the University of Californiaat Los Angeles. There, clinicians will use Open for MRI-guidedradio-frequency thermal ablation of primary and metastatic braintumors (SCAN 3/2/94).

Siemens competitor GE Medical Systems is also developing aninterventional MRI scanner, Signa MRT. The system has a superconducting0.5-tesla magnet in a "double doughnut" shape to facilitateaccess to the patient. Unlike Open, the GE system will be dedicatedto interventional procedures.