
A Gamma Knife instalation similar to the one Neila used at Presbyterian Hospital
The patient lies on the stretcher with their head clamped in a restraining frame. Thus immobilized, the head is introduced into the center of the aparatus where the beams of radiation are brought together at the tumor site. The bulk shields workers from the radiation and allows precision aiming of the beams in the desired direction.
Inside the "helmet" are over 200 cells, each containing a sample radioative element such as Cessium 137. Channels are drilled from each cell at an angle so that escaping radiation from all cross at a single point in the middle, where the patient's head with the tumor is positioned by computor at precisely that spot.
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After her cancer metastasized to the brain, Neila again entered the descending spiral staircase that is the cancer patient's life. The first step--the original diagnosis--was the biggest, but it led to the mezzanine of remission and the return of a normal life--though with some modifications and only for a while. The step off that mezzanine was in some ways even larger, for it led to a level where all the merry-go-rounds and rollercoasters in the medical playground of cancer treatment are kept; and to what soon became the realization that at the bottom of the stairs lies not a cue or even a miracle, but the end of life.
The patient with brain cancer is in a double bind because the tumor frequently is inoperable and the "Blood-Brain Barrier" prevents traditional chemotherapy agents from reaching the tumor. That leaves radiation therapy, which, unlike chemo, is indiscriminte; while it will kill any cells exposed to it, focusing it on just the cancer cells is like trying to focus the light from a light bulb. Just as the light radiates in all direction from a bulb, so radiation emanates indiscriminately in all directions from its source. The solution Neila's medical team recommended was Gamma Knife surgery in which multiple beams of radiation are focused deep inside the brain inaccessible to tradional surgery but with scapel-like precision. On May 4th, 1997 Neila underwent this procedure: the 3.5 cm tumor in her frontal lobe was cauterized with 5,000 rads. Cranial images after the procedure showed only a black necrosis in the spot where the tumor had been.
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