The findings backed her husband Michael's contention that Terri would not have recovered if she were given additional treatment, as her parents requested, reports CBS News Correspondent Scott Rapoport.
"This damage was irreversible, and no amount of therapy or treatment would have regenerated the massive loss of neurons," Pinellas-Pasco Medical Examiner Jon Thogmartin said.
But what caused her collapse 15 years ago remained a mystery. The autopsy and post-mortem investigation found no proof that she had an eating disorder, as was suspected at the time, Thogmartin said.
Autopsy results on the 41-year-old brain-damaged woman were made public Wednesday, more than two months after her death March 31 ended a right-to-die battle between her husband and parents that engulfed the courts, Congress and the White House and divided the country.
Her parents cling to their belief that her condition could have improved, in spite of the autopsy report, their lawyer said.
She died from dehydration, Thogmartin said. He said she did not appear to have suffered a heart attack and there was no evidence that she was given harmful drugs or other substances prior to her death.
He said that after her feeding tube was removed, she would not have been able to eat or drink if she had been given food by mouth, as her parents requested.
"Removal of her feeding tube would have resulted in her death whether she was fed or hydrated by mouth or not," Thogmartin told reporters.
He also said she was blind, because the "vision centers of her brain were dead," and that her brain was about half of its expected size when she died 13 days following the feeding tube's removal.