All Holmium Laser Fibers are the Same, Right? Part 1: An Introduction April 05 2016
A tale of two fibers – it’s not the best quality; it’s not the worst quality
(upper left -- connector with huge glue ring, steel tube, glass ferrule and the fiber in the very center; upper right -- close-up of fiber input; lower left -- close-up of working tip; lower right -- comet on output of working tip)
While the above is not proof of “Stephen's Law”, it sure supports it. I’m Stephen. The photo series above is representative of the median quality we observed in testing 24 holmium laser fibers – one brand, two sizes -- that have sold in the hundreds of thousands of copies. Believe it or not, they came out of boxes of sterile pouches with IFUs. We gathered this collage, and many, many more, while developing our "Fiber IQ Test"™: an effort to establish a minimum performance level that, in our opinion, is required for safe and effective holmium laser URS. I’ll have more on the IQ Test at the end of this series.
Part 1: An Introduction
While introducing our latest laser fiber technology for URS to the marketplace, we found that much of our earlier decade of educational efforts had heavily eroded in our absence. (IQinc was acquired in 2006. We were excluded from participation in the medical device field during the non-competition period and did not get back into the game until we had developed significant improvements to urological laser designs.) Without InnovaQuartz’ debunking of popular myths and misconceptions through proven technological advancements, there has come a resurgence of erroneous information within the field, likely in support of marketing what are essentially identical fiber designs. Well, we are back and we are even more committed to debunking the field than before.
It’s not all bad news, really. Without IQ’s advanced fiber optic technologies for cleaning-up nasty laser output, lasers had to get better. There are no more 500 micron focal spot holmium lasers built and “the dance of the focal spot” is more of a waltz than the punk mosh pit of preceding lasers. But as lasers got better, holmium fiber designs came under severe pricing pressure and have now devolved back to the mid-1990s (or earlier, in the case of 'garage-made' fibers -- where any self-styled MacGyver with a tube of glue, a scrap of 400 grit and a blow dryer thinks they can make surgical fibers).
There is, unfortunately, a negative feedback loop in play; bad fibers breed bad science and bad science breeds worse fibers, ad infinitum. Where there are numerous unidentified variables that affect a performance parameter, studies of that parameter that cannot control those variables cannot reach valid conclusions. In short, correlation is not causation. While this concept is very well understood in scientific disciplines and journals (where papers are judged worthy -- peer-reviewed -- of publication in large part by the validity of the experimental design), technology papers in medical journals appear to escape such scrutiny. When you combine lack of scientific oversight with the deep pockets of advertising budgets of medical device giants…well, you can probably guess what the result is.
And it’s not just journals that are filled with clap-trap. It’s hard to find a ureteroscopy or endourology textbook where sections on lasers and fibers are not ghost-written by one or more of the big laser companies with more than half of the material drifting from not quite right to blatantly contrary to established science. It is sad, really…just one edition ago some of these book sections were approaching 90% correct.
(These blue and yellow highlighted excerpts provide an example: while the "optical densities" of air and vacuum are different -- 1.0003 (air) versus 1.0000 (vacuum) -- the refractive index of the fiber core -- Heraeus F300 silica -- at 532nm is 1.4573, so how much difference is 0.0003 going to make? Well, absolutely zero in terms of internal reflection efficiency, because it has nothing to do with that. It does change the maximum angle that can be turned laterally -- by a fraction of a hundredth of a degree -- so there is that. Oh, and fused quartz does not melt at 1610C, the fiber cladding does nothing to prevent tissue adhesion -- because it is not in contact with tissue, ever -- and the divergence of a beam is a constant at any distance....aarrgghh; this is just gibberish designed to sound complex and unapproachable: what I call 'contrived complexity'. That's a term you'll likely see me use again.)
Gobbledygook sales speak from a respected urology textbook
The goal of the “All Holmium Laser Fibers are the Same, Right?” blog series is to set some of this right. IQ is back and we have a huge stack of new technology for lasers in urology to sift through: we've filed a dozen patent applications (four have issued) and almost a dozen more working their way to the patent office this year. This time out we're not limiting ourselves to fiber optics technology; we’ve broadened our research to include lasers (two laser designs in three patent applications, one issued) and laser-to-tissue interaction.
So, if you have an interest in holmium/thulium laser and laser fiber performance, you’ll want to follow this blog on holmium fibers, and subsequent series on BPH, side fire fibers....
More on 'Stephen’s Law' of Advancing Technology and Corollary next time in, "All Holmium Laser Fibers are the Same, Right?"
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