Michael Brassloff was 71 when he underwent surgery at Thomas Jefferson University Hospital to remove a benign tumor. The former marathoner and elementary school principal barely survived.

During the procedure, a two millimeter tip of a carbon dioxide-cooled laser probe — inserted through a tiny hole in the Rhawnhurst man’s skull — snapped off. The pressurized carbon dioxide jetted directly into Brassloff’s brain with a force eight times more powerful than a nail gun. The resulting trauma resulted in “severe and permanent brain damage" and Brassloff lapsed into a coma, said his lawyer, Shanin Specter of the Philadelphia law firm Kline & Specter.

Brassloff, after emerging from his three-week coma, experienced a host of ailments: recurrent seizures, memory loss, difficulty with language, and trouble controlling his emotions, according to his lawyers. He filed suit against the medical device manufacturer, Monteris; the neurosurgeon, Kevin D. Judy; the neurosurgeon’s employer, Jefferson University Physicians, and Thomas Jefferson University in Philadelphia Court of Common Pleas.

The lawsuit alleged that Judy was ill-equipped to use the medical device, called a Monteris Medical NeuroBlate Sidefire. According to the complaint, Judy never had used NeuroBlate to treat the type of tumor affecting Brassloff and the probe had never been tested for that purpose. In addition, Judy, a Jefferson University professor, testified that he routinely ignored error messages during such procedures and didn’t know he could do diagnostic MRIs mid-procedure.

Neither Judy nor Jefferson University Hospital returned calls requesting comment.

Monteris voluntary recalled the NeuroBlate probe at issue in 2016.

On Feb. 11, Monteris agreed to settle the Brassloff suit for $12.75 million.

The case against Judy, Jefferson University Physicians, and Thomas Jefferson University was ruled a mistrial by Judge Marlene Lachman during the defense questioning of an expert witness Feb. 21.

The case will be relisted for trial, Specter said.

A frequent competitor in the New York City Marathon, Brassloff can now barely stand on his own two feet. He uses a walker. He falls often. He has trouble finding the right words to speak. “His injuries are permanent, regrettably,” Specter said. “He continues to struggle with those symptoms.”