By Cornelia de Bruin

Triplicate staff writer

Phoebe Olson walked around not knowing she had a ticking time bomb in her head for more than 20 yearsuntil June 12, when she dropped like a stone for no apparent reason and was rushed to Sutter Coast Hospital's Emergency Room.

Only then did she and her family realize the cranial time bomban Arteriovenous Malformationcould have killed her at any time.

The congential growth, a tangle of abnormal and poorly formed blood vessels and arteries, lies deep within her brain. Its position renders it inoperable.

andquot;People find out they have these when they either have a seizure or start hemorhaging, or during an exam done for a completely different reason,andquot; said Dr. Edward Sadar, a retired neurosurgeon who practices medicine in the Columbus, Ohio area.

Sadar has treated patients for AVMs located in various parts of their bodies.

The rare congenital formations occur in less than 1 percent of the population.

The formations are of special concern when they are found in the brain because they can bleed and damage the brain.

When Phoebe collapsed during an exercise workout at The Club, her brain was bleeding. She didn't sustain permanent damage from the hemorhage, but she's hospitalized for the long haul as a team of Stanford Medical Center neurosurgeons work out the best course of treatment to help her.

Phoebe is also in horrific amounts of pain.

andquot;It's like a migraine times 10,andquot; said her mother, Leesa Davidson. andquot;She's in huge amounts of pain, incapacitated by pain; but they can't give her anything that puts her too deep of a sleep. They can only take the edge off the pain.andquot;

Phoebe's father, Don Olson, said that parents expect to deal with their own parents' illnesses and death, but that andquot;it's difficult with kids; one day someone is so vivacious...the next day collapsed on the floor with AVM, you don't even know it's there until it bleeds.andquot;

andquot;The outlook wasn't good when she first got to the hospital,andquot; Olson said. andquot;It was very traumatic see her go from being so active to near death.andquot;

He andquot;greatly complimentsandquot; the medical personnel who initially responded to his daughter, treated her and found a specialist at Stanford to treat her.

Her doctors can't remove the formation because to do so would damage her brain more than the formation potentially could.

Lacking that option, the physicians plan to insert an embolization tube into Phoebe's head and inject a medication that will seal the growth and prevent it from hemorhaging again. The procedure is scheduled soon.

andquot;I'm kind of excited about the procedure 'cause I can go home sooner,andquot; Phoebe said. andquot;It sounded good to me. They're going to give me an IV and I'll go to sleep and they'll do everything, and I'll have no memory of it. I will be in the hospital about three days, and then I'll go back to my apartment.andquot;

Afterwards, they will administer two radiation treatments in one-week intervals to damage the walls of the veins, which scars them but ultimately makes them stronger. Doctors will then determine whether or not a third treatment is needed.

andquot;Accurately guided radiation, which has been developed during the last decade, is a fantastic invention,andquot; Sadar said. andquot;With the location of her formation, surgery would do more damage to her brain.andquot;

The embolization material that flows through the tube into a patient's brain, he added, is frequently a plastic material or a glue. Over time it seals off the blood vessels and prevents them from bleeding more.

andquot;Usually the end result is a cure,andquot; Sadar said.

Until her medical procedure can be done, however, Phoebe is also fighting a condition common to brain injury patients: cerebral salt wasting. She has to take sodium pills to ensure that her salt levels don't drop too low, which could put her into a coma.

The sodium medication accompanies an anti-nausea medication she's taking to counter the effects of the sickening pain that has ruled her life since June 6.

As Phoebe and her mother awaited the scheduled procedure last week, Leesa began physical therapy, prescribed to keep her strong.

andquot;She met the Delta dog last Friday,andquot; Leesa said, referring to specially trained canines that help long-term patients andquot;get better.andquot;

But a migraine headache hit Phoebe shortly after the two-block walk from the women's apartment to their physical therapy appointment.

The pain was so overwhelming, her mother said, that they spent 12 hours in an emergency room for treatment June 7.

It's from that point that Phoebe is coming back.

andquot;She needs silence and darkness until the pain goes away,andquot; Leesa Davidson said. andquot;She can't talk on the telephone, that's too hard.andquot;

Mostly, Phoebe wants the surgical procedure to happen soon so that she can regain her former life: that of a College of the Redwoods student and teaching assistant for Del Norte Unified School District.

andquot;You feel your child's pain, it's very difficult when you see your child suffering,andquot; Olson said. andquot;The doctors are very optimistic about the procedure.andquot;

Olson and his daughter, Jaden, 17, plan to spend this week with Phoebe in Palo Alto.

andquot;We've tried to keep her occupied, but now she needs a quiet time,andquot; he said.

andquot;I'm more worried about my dog Chi-chi who needs medicine than I am about the procedure,andquot; Phoebe said. andquot;I miss everyone, my family and my friends.andquot;

How you can help

?Send a card:

If you want to contact Phoebe and her mother, Leesa, write to:

Phoebe Olson/Leesa Davidson

1100 Welch Rd.

Apt. 4C

Palo Alto, Calif. 94304

andquot;Cards help a lot, she likes to read them and we've been

putting up all the cards she's received,andquot; Leesa said.

?Assist financially:

A friend of the family has set up an account at U.S. Bank to

help defray her expenses:

The account is a VISA Travel Money Card. If you wish to

contribute funds, tell any teller at U.S. Bank that you wish

to deposit funds to Olson's VISA Travel Money Card.