Siemens delays FDA filing for P8

Siemens Medical Systems has delayed filing a 510(k) applicationwith the Food and Drug Administration for marketing its 0.2-teslaMagnetom P8 magnetic resonance imaging system. The company hadplanned to seek FDA clearance in mid-February for its first U.S.venture in low-field MRI, according to Chris Ruebeck, MRI productmanager.

Delaying the FDA filing should not prevent Siemens from meetingits late spring or early summer target for the launch of P8 salesin the U.S. The vendor plans to ask for market approval no laterthan mid-April, Ruebeck said.

The delay was a matter of establishing priorities in the backlogof planned FDA filings, according to Siemens officials. Applicationsfor several MRI coils and minor software upgrades were first inline for regulatory staff attention.

The P8 was developed by Siemens-Asahi Medical Systems, a Japanesejoint venture, and launched in Japan last April (SCAN 4/25/90).European sales were initiated later in 1990.

Siemens' main competition for the P8 in the U.S. comes fromHitachi. There are 35 U.S. installations of Hitachi's 0.2-teslaMRP 20 and its successor, the MRP 5000. Hitachi also introduceda 0.3-tesla system, the MRP 7000, into this market late last year.Siemens' low-field systems are installed at 10 facilities in Japanand Europe.

Both the Siemens and Hitachi scanners are permanent magnetsystems, which the manufacturers claim can generate profits onvolumes as low as three patients a day. Sales efforts for theP8 will be directed at the second-unit and small hospital markets,Ruebeck said.

The P8 is a compact system that can operate in 270 square feet,compared to 350 square feet for the Hitachi or 0.064-tesla ToshibaAccess. It weighs slightly under 9 metric tons, he said.

The unit's permanent magnet produces a horizontal field thathelps improve coil signal-to-noise performance. The system producesa 5-gauss line at 2.2 meters from the center of the magnet alongthe median plane. The gantry is 21 inches wide and 20.5 incheshigh. Options will include a full line of coils and three-dimensionalworkstation for multiplanar reconstructions, Ruebeck said.

BRIEFLY NOTED:

• Biomagnetic Technologies (BTI) of San Diego applied fora patent last month on a process to manufacture Josephson junctionsout of high-temperature ceramic superconducting material. Josephsonjunctions are used in the manufacture of superconducting quantuminterference devices (SQUIDS). SQUIDS, in turn, are a key componentin biomagnetometers produced by BTI and other companies. Biomagnetometersmeasure magnetic fields emanating from electrical activity inthe brain, heart and neuromuscular system.

The use of high-temperature ceramic SQUIDS could simplify anddecrease the cost of producing these diagnostic systems, BTI said.The company has not completed testing the technology for its usefulnessin biomagnetometry and other applications, however. BTI has fabricatedover 50 double-junction SQUIDS that can function using liquidnitrogen cryogens at the relatively high temperature of -196´Celsius.