quality problems at " NY brain-imaging lab"

NEW YORK – A respected brain-imaging center run by Columbia University has halted some research after federal officials repeatedly complained that patients were getting drugs that failed purity tests.

The Food and Drug Administration found in a series of inspections that the center had failed to correct manufacturing problems in a lab that makes experimental drugs injected into psychiatric patients to help capture images of brain activity.

In one warning letter, an FDA office in New York described problems dating back to at least 2004. It cited a litany of violations, including a failure to reject batches of medication that didn't pass required tests. The drugs were for patients undergoing a type of brain scan called positron emission tomography, or PET.

"We are concerned about the quality control systems and procedural problems that have allowed these significant deficiencies to occur," the FDA told the center in the letter, written in December 2008.

In a statement sent Saturday to The Associated Press, Columbia University Medical Center said it was restructuring the laboratory that produces the drugs for the Kreitchman PET Center.

It said an internal investigation, performed at the FDA's request, had found "no evidence of patient harm," but that all activities relying on the manufactured compounds had been suspended while reforms were undertaken.