TULSA, Okla. (AP) — A 15th medical negligence complaint has been filed against an Oklahoma City surgeon who made international headlines after performing a risky operation in 2006 that left a Russian teen brain dead.



Plaintiff Linda K. Martin filed the civil complaint against surgeon Paul Christopher Francel in Oklahoma County District Court last Wednesday.



Meanwhile, as many as 11 of the cases against Francel could go to mediation this month.



Martin's attorney, Marissa Osenbaugh, did not discuss the specifics of the complaint Monday, but said, "any time a doctor has that many claims in that short amount of time, it obviously raises some questions."



David McPhail, an attorney for Francel, said Monday he was undecided whether he would represent Francel in the Martin case. He has previously said that he has ordered his client not to discuss any of the other cases.



Along with the negligence complaints, Francel is a defendant in a wrongful death complaint brought by Sabit Kurbanov, the father of the 16-year-old Russian boy Francel operated on.



Francel has already agreed not to practice medicine while under investigation by state medical officials, and the Oklahoma Board of Medical Licensure and Supervision will not say if the investigation stems from the Russian boy's death or other matters. The probe could take several months.



Francel attracted international attention in 2006 after agreeing to perform a free — and risky — operation on David Kurbanov, who came to St. Anthony Hospital in Oklahoma City to have a lifesaving procedure.



Doctors in Moscow discovered a tumor that had wrapped around David's brain stem, crowding the portion that controls involuntary body functions such as balance, swallowing and appetite.



Surgeries like David's have a high chance of complications during recovery, but on the day of the October 2006 surgery, doctors told David he'd see his father in a few hours. And that night, the local news ran a feature story on the operation and said David could be going home in three days.



In the weeks following the operation, Francel said David was able to breathe on his own for short periods and follow rudimentary commands, but eventually succumbed to infections he had been battling since before the operation.



The boy slipped into a coma and was declared brain dead. He died in June 2007.



After David became brain dead, Sabit Kurbanov, the father, charged that Francel and the hospital were more interested in promoting themselves than properly caring for his son — allegations they denied.



Why David never recovered is unclear. Francel told the AP in a 2007 interview that the boy was in a weakened state before the surgery, and that the boy's father was frustrated with his son's condition and removed him from the case.



"I did everything that could possibly be done, and so did the team there," Francel said then. "In neurosurgery, if you have a tumor in your brain stem, it's almost a death sentence."



Copyright 2009 The Associated Press.