Fiducial Markers and Cyber-Knife Preparation
Cyber-Knife Bing Image |
Four in the morning has never been a good time for me to start my day. But, when I have a 2 hour and 15 minute drive before an important appointment, I manage to spring out of bed without hitting the snooze button on my alarm. Such was the case on an early October Friday a couple of weeks ago. Why I was wide awake and jumped out of bed as quickly as I did, making it out the door earlier than expected, had everything to do with GOLD. In the dark, my husband and I began our westward trip on I-40 to Chapel Hill.
We sailed smoothly into my 8:00 am appointment for the processing of paperwork and for my physical preparation for the fiducial markers placements. All the steps needed for this procedure were happening quickly. But, then it wasn’t. Everything slowed to--what felt like--a stopping of time. I reclined on a gurney, my husband--i-Pad in hand-- in the chair beside me. We waited . . . and waited. It was well beyond my scheduled time before I was pushed to the room where the procedure would take place.A nurse did arrive that day, pushing me to whatever room I was destined for. As the wheels on my gurney rolled, she asked how I was. I replied, “Not dying as long as there are options.”
“Never heard that one before,” she said.
In the room at last, I moved my body onto a table where the procedure would take place. I was strangely calm. In the past, my body has visibly shook from the terror inside me that I could not control. On this day, I did not need a “calm me down drug”. As I said, I was strangely calm. I believe the familiarity of lying on a table with people moving around me going about their particular roles is not as frightening to me anymore. It has become all too commonplace.
Once secured on the table, pictures were needed of my lung, so through the big white doughnut scanner I went. It was quick and easy.
Next, since the procedure was occurring to my right lung, I was placed on my left side. It was not the most comfortable of positions—right arm resting on the side of my head, left arm tucked along the left side of my body. I looked forward. My eyes immediately caught the image of my lung with the circular white spot clearly visible. There was a black line pointing to the spot with a measurement of 6.99 cm labeled on the screen. That was the distance the needle was going to penetrate my body in order to reach my tumor.
The awareness of my surroundings ended as soon as I felt the sedation taking me away to nothingness.
So much time went by before I regained complete consciousness, but of course I didn’t know this until I was told. I learned that when the needle entered the plural cavity that surrounds my lung, a pressure change occurred, air entered that space and my lung collapsed—a pneumothorax. Upon hearing this, I was having no difficulty breathing so I thought, “All must be fine.” It was—now. Since my lung collapsed, a chest tube had to be inserted allowing an exit route for the air so my lung could re-inflate. My lung didn’t cooperate completely. There remained a small pneumothorax. Thankfully, the procedure continued. While in recovery, I had two more x-rays done over a two hour period—of which I mostly slept--before it was decided it was not necessary for me to spend the night in the hospital.
In the middle of all that waiting for my lung to recover, I threw-up. The first time was rather comical. The first x-ray was about to be done via a traveling machine. The technician had placed the machine outside my recovery station. I must have just awakened because I remember looking toward her and saying, “Oh no”, I feel sick. As I tried to delay the actual act of throwing-up, the x-ray tech could only offer me a trash can. A trash can! Can you believe that? In a hospital, I was offered a trash can. What is even more maddening is this: after being questioned about medications by the in-take nurse updating my information in the computer when I first arrived, I told her I will throw-up when given any kind of anesthesia. She made a note of it. Only later did I discover that no one took that seriously. I was not given an anti-nausea medication. My husband said that in the beginning of my recovery, one nurse handed my care off rather abruptly to another nurse—no idea why. Maybe she had to go to the bathroom. The new nurse asked me if I felt nauseated. I said, "No." The medication to relieve nausea was placed on the table beside me and was left there clearly not doing me any favors. Wow, thanks! I warned someone this was going to happen. It seems pretty important to pay attention to a patient that says they throw-up especially when the procedure they are undergoing involves being stabbed in the lung. Patient neglect is simply not cool.
Through another bout of throwing up—this time in a more appropriate receptacle—I learned that 4 gold flakes had been placed inside my tumor increasing my total worth. Four, because these fiducial markers will sometimes dislodge and move to new locations because of the lung’s continuous motion.
Fiducial marker placement is necessary in Sterotactic Body Radiotherapy (SBRT) done by a Cyber-Knife machine. Though I didn’t witness my procedure, I imagine it went something like this: A needle was inserted creating a path to the tumor. Then a guide wire with the gold flake on the tip was pushed through the tube and into the tumor. The guide wire was then pulled back out, prepared with another flake and re-inserted. When the flakes were in their places, the needle was removed. Blood from my own body was injected into the area. I am guessing that helped with clotting.
After I was given the “OK” for release, the chest tube was removed from my side. I was bandaged-up, and we headed home. What a day it was. I missed most of it even sleeping on the trip home.
Simulation For Cyber-Knife Radiation
On the following Friday I had the simulation for Cyber-Knife treatment done. A mold of my body was made so I wouldn’t move during the radiation procedure. Another scan was done so the final measurements could be calculated. Those measurements insured the least amount of damage to my healthy tissue from the radiation. The gold (metal) flakes will be the beacon for the machine. The radiation beams will hit my tumor killing every single tiny monster housed within--I hope.
I can’t wait. It starts this Thursday!
For those who want more information about this treatment please go to:
UNC Cyber-Knife Center, Department of Radiation Oncology
http://www.med.unc.edu/radonc/patient/treatments/ck
and http://www.radiologyinfo.org/en/info.cfm?pg=stereotactic
What equipment is used?
There are three basic kinds of equipment, each of which uses different instruments and sources of radiation:
1. The Gamma Knife®, which uses 192 or 201 beams of highly focused gamma rays all aiming at the target region. The Gamma Knife is ideal for treating small to medium size intracranial lesions. See the Gamma Knife page for more information.
2. Linear accelerator (LINAC) machines, prevalent throughout the world, deliver high-energy x-rays, also known as photons. The linear accelerator can perform SRS on larger tumors in a single session or during multiple sessions, which is called fractionated stereotactic radiotherapy. Multiple manufacturers make this type of machine, which have brand names such as Novalis Tx™, XKnife™, Axesse™ and CyberKnife®. See the Linear Accelerator page for more information.
3. Proton beam or heavy-charged-particle radiosurgery is in limited use in North America, though the number of centers offering proton therapy has increased dramatically in the last several years.
See the Proton Therapy page for more information.