An Orange County Superior Court judge has dismissed charges against a radiologist from Newport Beach and co-defendants accused of widespread worker's compensation fraud.

Prosecutors say they plan to refile the case.

On Dec. 13, Judge William Froeberg dismissed the 884 counts against Dr. Sim Carlisle Hoffman, 61, who was indicted by a grand jury in May 2011. Froeberg said he based his ruling on the fact that evidence was withheld from the grand jury.

Prosecutors had alleged that Hoffman, Dr. Thomas Michael Heric of Malibu, Louis Umberto Santillan of Chino Hills and Beverly Jane Mitchell of Westlake Village were part of a $17-million fraud scheme that billed insurance companies for expensive and unnecessary procedures, some of which were never performed.

Hoffman owns Advanced Professional Imaging, Advanced Management Services and Better Sleeping Medical Center, all located at 6800 Lincoln Ave., Buena Park.

Santillan worked as a bill collector for Advanced Professional Imaging. He was charged with 141 felony counts of insurance fraud, according to a news release from the Orange County district attorney's office.

Mitchell was in charge of insurance billing for all three of Hoffman's businesses. She faced the same charges as Hoffman.

Heric was a neurologist at Better Sleeping. He was charged with 296 counts of insurance fraud and one felony count of aiding and abetting the unauthorized practice of medicine.

In his ruling, Froeberg wrote that the grand jury should have been provided the evidence submitted by Hoffman's defense team.

"There were five or six competent experts in the field who were all familiar with the operations, but the prosecutors failed to present any evidence to the grand jury showing that the sleep center was run lawfully," Richard Moss, one of Hoffman's defense attorneys, said in a prepared statement.

Deputy Dist. Atty. Shaddi Kamiabipour said last week that she plans to refile the case around mid-January, and that the judge's dismissal was based more on a procedural error than on any lack of merit in the case.

The alleged $17-million figure may be higher in the refiling, which will target only Hoffman and Heric, Kamiabipour said.

Santillan and Mitchell may not face charges again, she said.

William Fleming, a member of Hoffman's defense team, said, "Should the district attorney decide to refile the case, it still won't clean up the fact that their office has already been provided with the opinions of several prominent medical experts who are prepared to testify that Dr. Hoffman practiced at Better Sleeping Medical Center appropriately and lawfully."

Hoffman is still a licensed doctor, according to state records. In 2001, the Medical Board of California disciplined Hoffman for excessive billing and subjecting a patient to procedures not considered medically necessary, prosecutors said.

Heric, also still a licensed doctor, has a felony conviction from 2008 for Medicare and Medi-Cal fraud. The neurologist served a 60-day suspension and 36-month probationary period and paid $50,000 in restitution, according to state records.