Comment by kelnos | Hacker News Reader

Comment by kelnos | Hacker News Reader

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> instead of attempting to close the hole completely in one go, install some kind of controllable shunt and gradually reduce the flow over a longer time, then once reduced to nothing, close the hole?

That would only work if they can find the hole. According to the article, it often doesn't show up on imaging, and even if they know roughly where it is (as in the case of a lumbar puncture gone wrong), it's still incredibly difficult to pinpoint, and patching it usually involves trial and error.

It wasn't completely clear from the article, but it sounds like often they don't ever really pinpoint the hole, even when they are able to successfully patch it. The patching process seems more like "spray and pray": do some patching (she had 22 patches done, I think I read), and once it seems like the leaking has stopped, they assume they got it. Not sure if this is true, but that's the impression I got.

For clarity, I had 4 rounds of targeted patching done, but I wanted to be clear that there were a total of 22 needles — it wasn't a high volume EBP, but smaller, directed patches with blood+fibrin.

Puncture leak sites rarely show on imaging, it's true. At Duke, Cedars, or other leak centers they have techniques for CTMs or DSMs that yield leak sites but that's usually for spontaneous CSF leak patients or post-surgical, not us puncture people. They're using a PCCT machine to find CSF venous fistulas at Mayo and at Duke, but again to my knowledge puncture leaks remain a needle in a haystack even on that quality of imaging.

> That would only work if they can find the hole.

Well either that, or "spray and pray" to fix unknown holes, but deliberately make another small, known, controlled hole that can relieve pressure and gradually be shrunk until it's shut.

I actually knew someone who had a valve like that installed because her CSF pressure kept changing. Periods of high pressure were the most dangerous and led to rapidly deteriorating mental function—and eventually death.

The valve never really worked well, and she didn’t live long enough to determine why.

Retired neurosurgical anesthesiologist (38 years) here. I performed 500-1,000 spinal taps.

>... deliberately make another small, known, controlled hole that can relieve pressure and gradually be shrunk until it's shut.

This would make things worse. The pressure has already been relieved by the original hole with subsequent loss of cerebrospinal fluid.

Post-spinal/dural puncture headache results from NOT ENOUGH CSF surrounding the spinal cord and brain as a result of its leaking out: thus, the brain sags and positions itself on the base of the skull rather than floating, with subsequent headache.

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