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Thur Feb 2. I am becoming even more comfortable pain-wise as my radiation oncology treatments continue. I've had three requests to explain more about this option and so this post will be of a more general nature.
General versus Local Analgesia
When I swallow morphine for chest pain, the morphine will enter my bloodstream and be available to all parts of my body. This is an example of a "general analgesic."
If I go to the dentist who injects novocaine into my lower jaw so that he can do a root canal, the novocaine is being used to block the nerves around the tooth in question--"local analgesia."
In the case of my cancer, it has spread to my bones--both my ribs and my spine. The rib pain has been around since October. The back (spine) pain had been gradually increasing for several weeks until I reached the point a couple of weeks ago where I was unable to lift my left leg without pain in the back.
Since October, I had been managing my pain with the drug Oxycodone and its long-acting form, Oxycontin. Up until New Years weekend, I had been making do with about 50 to 60 mg of oxycodone a day. Suddenly my pain increased markedly to the point where 120 mg of oxycodone was not controlling the pain. At that time, I was put on fentanyl patches. These patches release a steady stream of the morphine-like drug, fentanyl. Although the fentanyl did control the chest pain and did help with the back pain, I was experiencing weakness in my left leg. Pain control did not help with the weakness. Here is an image from a CT of my abdomen in December.
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| Sohr L Spine Dec 2012 |
Up until two weeks ago, I was treating my lumbar spine "generally" by taking oxycodone and then fentanyl. However, the pain was continuing to increase and there was an associated weakness in my leg muscle because of the tumor's presence in this area. At that point, I elected to try a local treatment, radiation to my Lumbar spine.
General Principles
Tumors generally multiply faster than ordinary tissues. While cells are multiplying (by dividing) they are very sensitive to radiation, like x-rays. Treatment with direct x-ray tries to deliver enough radiation to the tumor to kill it but not enough radiation to kill the surrounding tissue. You can see where this is tricky. In my case, I want radiation to the bony spine, but I want to minimize radiation to my spinal cord. One way of accomplishing this is to find two pathways to the area to be treated.
The high energy beam x-ray machine fills a room. There is a brownish colored cabinet to the rear of the machine which contains electric motors and controls.
This is the actual machine being used for my treatment.
The front part of the machine is shaped like a block letter C. The top stem of the C is the "gun" that delivers the x-rays. It is labelled "VARIAN" in the picture. The entire "C" rotates 360 degrees so that radiation can be delivered at any angle. The patient remains stationary on the table and this enormous x-ray machine rotates about.
The high energy beam x-ray is too powerful for decent imaging. Above Dale's head there is another x-ray gun that generates low energy rays for imaging.
On my first visit, about an hour was spent aligning my body to the table and to the machine. Several low energy x-rays were taken to hone in on the treatment window--the precise area of the body where the x-ray was to be delivered. Once this was identified, I received a series of tattoos that permitted a much more rapid alignment in the future.
With my current visits, I am placed on the table. The tattoo marks on my chest and abdomen are used to make sure that I am properly aligned to the table and machine. Then a low beam x-ray is taken to demonstrate that the treatment portal is accurate--this is the second check on location. For my spine treatment, I am given about 30 seconds of high energy radiation from the front. Then the machine is rotated 180 degrees and I receive a similar dose from the back. By splitting the total dose into two segments, the surrounding tissues are spared 50% of the dose while the treatment area is treated twice.
These treatments are working very well. I have much better leg mobility than 2 weeks ago and much less pain as well.
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Later this morning I have an appointment with Dr. Palchak. I am hoping to use his experience and wisdom to lay out a reasonable treatment plan for the next month or so.
Tumors generally multiply faster than ordinary tissues. While cells are multiplying (by dividing) they are very sensitive to radiation, like x-rays. Treatment with direct x-ray tries to deliver enough radiation to the tumor to kill it but not enough radiation to kill the surrounding tissue. You can see where this is tricky. In my case, I want radiation to the bony spine, but I want to minimize radiation to my spinal cord. One way of accomplishing this is to find two pathways to the area to be treated.
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| High Energy Beam X-Ray Machine |
This is the actual machine being used for my treatment.
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| Adrienne and Dale who do my treatments each morning. |
The high energy beam x-ray is too powerful for decent imaging. Above Dale's head there is another x-ray gun that generates low energy rays for imaging.
On my first visit, about an hour was spent aligning my body to the table and to the machine. Several low energy x-rays were taken to hone in on the treatment window--the precise area of the body where the x-ray was to be delivered. Once this was identified, I received a series of tattoos that permitted a much more rapid alignment in the future.
With my current visits, I am placed on the table. The tattoo marks on my chest and abdomen are used to make sure that I am properly aligned to the table and machine. Then a low beam x-ray is taken to demonstrate that the treatment portal is accurate--this is the second check on location. For my spine treatment, I am given about 30 seconds of high energy radiation from the front. Then the machine is rotated 180 degrees and I receive a similar dose from the back. By splitting the total dose into two segments, the surrounding tissues are spared 50% of the dose while the treatment area is treated twice.
These treatments are working very well. I have much better leg mobility than 2 weeks ago and much less pain as well.
---------------------
Later this morning I have an appointment with Dr. Palchak. I am hoping to use his experience and wisdom to lay out a reasonable treatment plan for the next month or so.
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