Monday, October 03, 2005

E pur si muove, or, Revenge of the Reservoir

Among the many joys of dealing with cancer is the pleasure of becoming acquainted with new bits of medical technology. Since Lisa’s diagnosis, we’ve met the various infusion pumps (and the formulae used to program them), the port or VAD that made the first chemo _so_ much easier, not to mention multiple MRI machines, including a portable version accessed via loading dock — try that one in New Hampshire in January! — CT scans, bone scans, a thalium scan (the tech was really good at explaining that one), plus a host of things like butterfly needles and sadistic blood pressure machines that won’t do their job on the first or even the second try. (Those things squeeze really, really hard....)

However, the device currently causing extra fun and games is the Selker reservoir through which Lisa’s intrathecal chemo has been administered, and from which cerebrospinal fluid will be sampled. Now, her primary oncologist wanted an Omaya reservoir, which seems to be the most common variety of port used for intrathecal chemo, but for some reason, the neurosurgeon at Dartmouth-Hitchcock inserted a Selker reservoir instead. (Actually, one of the nurses mentioned that the Selker is lower profile than the Omaya, which does make a cosmetic different when it’s in your temple.) We’re not totally sure that he communicated this fact, either.

What he definitely didn’t communicate was any of the specs on the Selker, so that, for five treatments, Lisa’s primary oncologist had trouble accessing the port. (Imagine being repeatedly stuck in the scalp with a needle.... Not fun.) The first week, she was sent to radiology to be accessed under flouroscope, and the oncologist marked the spot with indelible marker. However, the next week, he still had trouble. Once we got home, Lisa commented that she thought the thing had shifted — it felt to her it was in a different spot — but I said, oh, no, that surely couldn’t be the case. We both agreed that didn’t seem likely.

And yet.... The primary oncologist, who deals with these things every week, kept having trouble finding it. The more I looked at it, the more I thought the bump was a little different. Lisa said she was almost sure it had shifted. Greg the nurse kept shaking his head when he prepped it. So after we had to move treatment by one day because they couldn’t find room in radiology to access the port, all the doctors independently did further research on the Selker.

And guess what? It does move! Unlike the Omaya, it’s not stitched into place, but shifts every so slightly on its tether. This is the first thing that has made me slightly queasy in Lisa’s entire treatment, though we are assured that it can’t actually come loose. So the access point is different every time.

Of course there’s a solution: Lisa will go to radiology, get the reservoir accessed, and then go to oncology for her main appointment. This does involve walking through the halls with a needle sticking out of her head (literally!), but the radiology folks have gotten good at disguising it with a bandage. (The first time, though, they didn’t cover it, and poor Lisa had to walk through a waiting room full of horrified people, smiling and saying, “don’t you love my new punk jewelry?”) And it is much, much less painful.

I suppose it’s really ungracious to complain. After all, the reservoir, Selker or not, moveable or not, is doing its job. The methotrexate has worked: there is no sign of cancer in the CSF, and the chemo has been discontinued unless and until the cancer comes back. For now, the Selker will be used only to take samples of CSF, and it’s one hell of a lot easier than a spinal tap.

But who’d expect the thing to move??