Four days before 14-year-old Victoria Gertson was charged by Prince George's County police with killing her mother, a brain doctor hired by the state concluded that 48-year-old Maria C. Gertson died of natural causes.

The finding, by Dr. Juan C. Troncoso of Johns Hopkins University Hospital apparently on May 27, went unreported to Prince George's authorities, according to those authorities, who, acting on earlier information, charged the Langley Park teen-ager on June 1 with murder in her mother's death and then sought to have her held without bond.

"For the evidence to lay there in the bureaucracy all this time is pretty shocking," said Joseph DePaul, the lawyer representing Gertson, who is free on $30,000 bond and attending summer school.

"She's quite relieved and somewhat stunned," DePaul said. "I didn't think any crime had been committed.

"Frankly, this rules out any talk of any murder," DePaul said.

State's Attorney Arthur A. Marshall Jr. was unavailable yesterday, and several of his assistants either declined to comment or did not return phone calls.

Robert Miller, chief of homicide detectives, said a meeting is scheduled next week between police and prosecutors to decide whether to drop charges.

Miller said police had acted on earlier information that the death was a homicide.

That information, according to Miller, was given orally May 25 by Dr. Dennis Smyth, the assistant state medical examiner who signed the final report this week concluding that Maria Gertson "died as a result of a brain abscess. The manner of death is natural."

With the autopsy document was a three-page report from Troncoso, a neuropathologist, asserting that the abscess that caused the death was "at least" four to six weeks old.

The Troncoso portion of the autopsy was dated May 27.

Gertson died May 24 after being in a coma for three days, and her body arrived at the coroner's office in Baltimore on May 25.

Troncoso, describing himself as a consultant to the state, would not discuss his findings yesterday.

Smyth could not be reached for comment.

"Apparently, there was a snafu," said one high-ranking county police officer who asked not to be identified. The final autopsy report, dated July 20, took an unusually long time to arrive, he said.

About 5 a.m. on May 21, according to police, Maria Gertson came home from a party, and she and her daughter quarreled in the mother's bedroom.

Police alleged that Victoria then "slammed" her mother's head into the nightstand. When she checked on her mother later, she was unable to revive her.

Although police believed Maria Gertson had been drinking the night before, alcohol tests conducted during the autopsy were negative. But her reportedly drunken manner was consistent with the effects of a brain abscess.

After visiting her mother in the hospital and later attending the funeral, Victoria Gertson surrendered to police May 31 and was charged as an adult. Police said then that the mother had died from the head injury.

The autopsy report made no mention of a blow to the head as a cause of death, however. Instead, the medical examiner found her death attributable to the brain abscess, caused by infectious bacteria, that had been developing for "at least four to six weeks."

"It appears the so-called experts knew on May 27th" the mother's true cause of death, said DePaul, the lawyer. "They've had a murder charge hanging over this kid since the first of June.

"It's really a bad scene altogether. The state opposed this girl making bond in court on the one hand and seemed to have evidence on the other negating any murder charge," he said.

DePaul said he had repeatedly phoned the prosecutor's office since learning late Thursday of the autopsy report, but his calls weren't returned.

"I think it's pretty sick," said Mary Ann Gertson, the girl's aunt. "The whole thing is very, very strange." She said Victoria was confident she would be acquitted of any charges.

According to Victoria's father and brother, the mother and daughter generally got along well and shared an interest in citizens band radio.

Maria Gertson, born in the Canary Islands, used "Singing Canary" as her handle.

Her daughter was known on the CB bands as "38 Special."

Andris J. Gertson said he and his wife had been estranged for several years but continued living together. Gertson said his daughter frequently skipped classes at High Point High School, where she was a freshman. In April, the school dropped her from the rolls for lack of attendance.

"I had no idea my wife was ill," Andris Gertson said yesterday. "The only thing is headaches, but she had complained about that every since I'd known her, off and on, since 1960."

Since her mother's hospitalization, Victoria Gertson has been staying with a friend and the friend's mother, who retained counsel for her and posted bond.

Andris Gertson said yesterday, "She's gonna come back home, I know that."

That is also his wish, he said, "with certain stipulations. She was allowed to run wild all the time. That can't happen. She can't be a vagabond."