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The Op Notes for my gallbladder removal, a couple of weeks ago, included this sentence:

A 24-French Blake drain was then placed in the gallbladder fossa with a concern for duct of Luschka leak given the raw surface of the liver at the time of closure.

This led me to wonder who Blake was, and in what sense his drain had 24 Frenches, so I looked into it a bit.

Wikipedia explains that

The French scale or French gauge system is commonly used to measure the size of a catheter. […]

The French size is three times the diameter in millimeters. 

It's interesting that they don't just say "8 mm" instead of "24 French" — maybe because "10 French" would be "3.33̄ mm"?

Anyhow, the "French" part really should be "Charrière" — and outside the Anglosphere, it apparently is:

Joseph-Frédéric-Benoît Charrière (March 19, 1803 – April 28, 1876) was a Swiss-born French manufacturer of surgical instruments. […]

He developed and improved a number of instruments, especially hypodermic needles and catheters; the French catheter scale is named after his work. […]

His name is used as a measuring unit for the outer diameter and the general size of urological instruments, endoscopes and catheters for a various purposes (1 Charrière = 1 mm outer circumference ~ 1/3 mm outer diameter). In English-speaking countries, the name "Charrière" was found difficult to pronounce. Thus, the term "French" was rapidly adopted in its stead. This is now generally used as a measuring unit for medical catheters and introducers (1 French = 1/3 mm).

As for Blake, Joseph Meyerson, "A brief history of two common surgical drains", Annals of plastic surgery (2016) explains:

Every surgeon should be familiar with the Jackson-Pratt drain and Blake drain, 2 of the most frequently used closed suction, negative-pressure drainage devices in surgery. […]

The JP drain can be traced back to an article from 1971 by Dr Frederick E. Jackson and Dr Richard A. Pratt, 2 neurosurgeons from the Naval hospital at Camp Pendleton in California. These surgeons were attempting to develop a sterile, closed system drain that could be used in postoperative craniotomy cases, as they termed it in their article, the "brain drain". The original design was a flat, rectangular silicone drain with multiple perforations and internal ridges to provide consistent drainage while preventing collapse when under suction. This design includes a hubbed portion, often opaque that is placed in the body cavity with clear tubing connecting it to the reservoir. The JP drain today continues to be a popular drain of choice for surgeons in all subspecialties. Although many practitioners will ask for the JP and Blake drain by name interchangeably, there are significant differences in the design.

The origin of the BLAKE drain, as it is spelled on the distributors' (Ethicon, Inc) website, has a history that is less obvious and defined. A literature search does not elucidate any useful information on the drain's history, such as that of Drs. Jackson and Pratt, and this information is not stored at Ethicon's research and development department. Although, if one searches the original patent to the Blake drain issued in 1983, it is found that the inventor's name is Larry W. Blake, presumably the origin of the drain's name. In contrast to the JP drain, the Blake drain's design has a cylindrical, silicone catheter with a solid crossed-shaped center and 4 open fluted channels to prevent the plugging of draining perforations. The Blake drain's original design is hubless with an even transition from the perforated to nonperforated portion. Both, the JP and Blake drains, accomplish the task of closed suction negative-pressure drainage. They remain patent under forces that can reach multiple atmospheres and have designs that avoid obstruction of drainage by body tissues.

I haven't been able to find much about Larry Blake, except that in addition to this one, he's responsible for about 37 other patents in medical area, most recently one filed in 2016.  Having his eponymous drain in place for a couple weeks has not been fun, since the hole in my abdomen hurts a lot when I move, bend, cough, etc. — but presumably the alternative would be much worse. And fingers crossed, it's coming out tomorrow.

Finishing off the lexicographical analysis of that sentence from my Op Notes, I wondered what the "duct of Luschka" is. According to Thomas Schnelldorfer et al. "What is the duct of Luschka?—A systematic review", Journal of Gastrointestinal Surgery 2012:

The term "ducts of Luschka" should be abandoned and should be replaced by the correct term of "subvesical bile duct". The variability in anatomic location of subvesical bile ducts puts them at risk during hepato-biliary operations. A better understanding of ductal anatomy is elemental in preventing and managing operative injury to the subvesical ducts.

Far be it from me to enforce terminological prescriptivism on the surgeons, who seem to have done the right thing by whatever name.



  1. KevinM said,

    February 17, 2020 @ 3:53 pm

    I'm assuming these are nothing like the French drains in my basement. Best wishes for your speedy recovery.

    [(myl) Wikipedia's description of a French drain is "a trench filled with gravel or rock or containing a perforated pipe" — as far as I know, my surgeons omitted the gravel, though it doesn't always feel that way :-)…]

  2. Michèle Sharik Pituley said,

    February 17, 2020 @ 3:57 pm

    > In English-speaking countries, the name "Charrière" was found difficult to pronounce.

    This surprises me. We'd flatten the pronunciation, like we do any French word, of course (Shar-ee-air), but "difficult"??

    [(myl) I agree — we've borrowed lots of words in -ière, like brassiere, derriere, premiere, etc. Maybe the docs just wanted something shorter, one syllable instead of three? Or maybe they worried that the various alternative pronunciations of such words would be confusing?]

  3. MattF said,

    February 17, 2020 @ 4:29 pm

    So… in fact, one French is not 1/3 mm, but 1/pi mm.

    [(myl) No, it's really 1/3 mm — Wikipedia explains that "From the basic math equation C = πd, it follows that the catheter's circumference in mm is only slightly (about 4.7%) greater than the French size." Because (pi*8-24)/24 = 0.04719755 ]

  4. Theophylact said,

    February 17, 2020 @ 4:48 pm

    The French drain seems to be named after Henry Flagg French (1813–1885) of Concord, Massachusetts, who popularized them, according to Wikipedia.

  5. Gregory Kusnick said,

    February 17, 2020 @ 5:22 pm

    If one French is defined to be exactly 1/3 mm, then it's not the case that "the 'French' part really should be 'Charrière'", since one Charrière is (apparently) defined as 1 mm of circumference and hence 1/pi mm of diameter.

    In other words, if Wikipedia is to be believed, this is not just a terminological difference but a difference in the actual units of measurement (analogous to quarts v. liters).

  6. J.W. Brewer said,

    February 17, 2020 @ 5:47 pm

    Hubert von Luschka (1820-1875) is apparently commemorated in the common (well, common among relevant specialists, or so I surmise …) names of multiple different features of the human anatomy, so he could potentially lose the ducts and hold on to the rest — unless giving way on the ducts would open the floodgates and embolden onomastic revisionism with respect to the rest of his portfolio. https://en.wikipedia.org/wiki/Hubert_von_Luschka

  7. Philip Taylor said,

    February 17, 2020 @ 6:04 pm

    Very sorry to learn that your gall bladder removal was not entirely straightforward, Mark. It is only after reading accounts such as yours that I appreciate just how lucky I was to be able to have mine removed using keyhole surgery — the procedure was carried out at about 08:00, and by 13:30 the same day I was in the pub garden next to the hospital drinking a beer and tucking into moules frites.

  8. J.W. Brewer said,

    February 17, 2020 @ 6:05 pm

    Ethicon's catalog refers to "BLAKE® Silicone Drains," so they purport to have a registered trademark on "Blake" and are perhaps trying to promote the ALLCAPS style (even if others don't necessarily follow suit) in order to emphasize the trademark aspect of the word. Of course, Mr. Blake's original 1983 patent expired long ago, and competitors of Ethicon ought (from a patent and trademark perspective, w/o getting into what they would need to do to get FDA approval) both to be free to manufacture drains embodying the invention disclosed in the patent and also be free to market those drains in a way that accurately describes the kind of drains that they are.

  9. VV said,

    February 17, 2020 @ 6:26 pm

    Physician (though non-surgeon) who's a longtime mostly-lurker here. I find the "French" unit (not to mention the "gauge" unit, which is inverse to width!) very annoying and wish that we just used metric. Unfortunately, both units seem here to stay.

    I hope you feel better soon (but keep taking this opportunity to comment on interesting uses of language in medicine – there are so many!)

  10. wanda said,

    February 17, 2020 @ 6:56 pm

    My impression is that anatomists and biologists are generally trying to move away from names that feature people's names towards descriptive names. The term "subvesical bile duct" tells you something where they are located and what they do, whereas the term "ducts of Luschka" don't.

  11. AntC said,

    February 17, 2020 @ 11:57 pm

    Yes I'm unconvinced about the difficulty of pronouncing. Why not just murder the pronunciation as usual?

    I have a 'Dupuyron's Contracture' pronounced "doo-pee-ronz", apparently.

  12. Peter Grubtal said,

    February 18, 2020 @ 4:32 am

    ..from pedants' corner:
    glad to see that it's the drain that's eponymous and not Mr. Blake.
    The latter usage .."the eponymous Mr. Blake" is becoming almost universal now (on Wikipedia, for example), and this old fogey will only grudgingly accept that "if that's the way everyone uses it, then it's correct..".

  13. Stephen Goranson said,

    February 18, 2020 @ 4:48 am

    Speaking of one Blake and innovative surgery reminds me of Geoffrey Keynes (1887-1992), who made advances in surgical technique and as well published extensively on English literature, including his Oxford UP edition of the poet William Blake.

  14. David Marjanović said,

    February 18, 2020 @ 6:28 am

    Compare Polish notation, named after a Mr. Łukasiewicz.

    Maybe the docs just wanted something shorter, one syllable instead of three?

    Really just two syllables in the original outside maybe of professional singing: shar-YAIR.

  15. John Shutt said,

    February 18, 2020 @ 7:28 am

    I'd been thinking about Jan Łukasiewicz and "Polish notation" though all this, but that falls on the other side of the difference between merely not knowing how to pronounce the name, and /knowing/ you don't know how to pronounce it. A typical English speaker would be actively aware, through the spelling, of not knowing what to do with an L with a cross through it, and might also have doubts about the "cz" at the end.

  16. Philip Taylor said,

    February 18, 2020 @ 7:36 am

    For me (a native British speaker, not a native Francophone), I find it hard to imagine "Charrière" being pronounced as David M. suggests — to my ear, it clearly has three syllables /ʃɑʁ ʁi ɛːʁ/. I suppose that if pronounced very quickly it might sound like two, but I am not entirely convinced.

  17. ajay said,

    February 18, 2020 @ 8:21 am

    It's pretty common to measure the size of long cylindrical things (like, for example, ropes) by their circumference rather than their diameter. Bullets (9mm, .45, etc) are something of an exception. The reason's very simple: it's a lot easier to measure circumferences. You just wrap a bit of string around the object, unwrap it and measure its length. All you need is string and a ruler, or a tape measure. Now imagine getting an accurate diameter of, say, a 16-inch cable – possible, but you'd need rather more equipment. (This confused me on reading historical naval documents – I was imagining cables 16 inches in diameter, which would have been basically trees.)

  18. MattF said,

    February 18, 2020 @ 11:05 am

    Not to be rude about this, but you could always measure the circumference and divide by pi. And, yes, I'm a scientist.

  19. Peter Grubtal said,

    February 18, 2020 @ 12:13 pm


    not to be rude about this, but I think you've missed the point. If it's well known that cables, for example, are classified for size like this, the circumference is fine.
    You might as a scientist have no problems with dividing by 3.1416……., but on a ship with many sailors having little formal education, why not just refer to the cables by their circumference…

  20. MattF said,

    February 18, 2020 @ 12:22 pm

    @Peter Grubtal
    I confess that my brother-in-law once asked me how to estimate the diameter of a curtain rod, given the circumference— I gave the 'obvious' answer, and he was extremely amused. I guess I haven't quite forgiven him for that.

  21. Mark Meckes said,

    February 18, 2020 @ 1:40 pm

    Not having had to learn much about gallbladders, the word that leaped out at me in there was fossa.

  22. Mark P said,

    February 18, 2020 @ 3:22 pm

    Mark Meckes — That word leapt out at me as well, because I recently ran into almost the exact same word. After about 50 years I decided to reread the Lord of the Rings. Tolkien sometimes uses archaic, or at least not often used words. One that I noticed and had to look up was fosse, which has essentially the same meaning as fossa, only for land forms instead of biology.

  23. Philip Taylor said,

    February 18, 2020 @ 4:28 pm

    Most Britons would be familiar with "fosse", as we have a rather famous entity "the Fosse Way".

  24. Mark P said,

    February 18, 2020 @ 9:30 pm

    Phillip Taylor— Is the Fosse Way given the dictionary pronunciation in Britain? Also, would you say that the meaning of fosse is generally known, or is it just a name?

  25. Gregory Kusnick said,

    February 18, 2020 @ 11:08 pm

    Nothing to do with Bob Fosse, I assume.

    On measuring circumference v. diameter, I imagine that for large, somewhat squishy things like ropes, wrapping a string around it is more accurate than pinching it in a caliper. For tiny metal surgical instruments, I imagine the reverse is true. But perhaps that wasn't the case when Charrière invented his measurement scale.

  26. Philip Taylor said,

    February 19, 2020 @ 4:57 am

    [The Fosse Way] I have only ever heard it pronounced as /fɒs/, and the LPD confirms that, offering /fɑːs/ as the American equivalent. As to whether more than a handful know what a fosse is, I suspect not, in general, but I also suspect that it lingers on as a dialect term (I don't have a m English dialect dictionary to hand). Certainly Thomas Hardy used it — "they wound down the defile spanned farther [sic] on by the old castle arch. and forming the original fosse of the fortress".

  27. ajay said,

    February 19, 2020 @ 5:40 am

    Not to be rude about this, but you could always measure the circumference and divide by pi.

    Yes. Is that easier or more difficult, would you say, than measuring the circumference and not dividing by pi?

    On measuring circumference v. diameter, I imagine that for large, somewhat squishy things like ropes, wrapping a string around it is more accurate than pinching it in a caliper.

    Also a good point.

  28. Alyssa said,

    February 19, 2020 @ 11:44 am

    I wonder if the problem with "Charrière" wasn't the pronunciation, but the spelling. After all, doctors and nurses write things down a lot, and if you're not familiar with french spelling that's a particularly tough one to spell. It wouldn't surprise me if the "1 French" usage started with some frustrated doctor who couldn't remember how many "r"s went where and just said "screw it, it's that french word, they'll know what I mean" instead.

  29. Ellen K. said,

    February 19, 2020 @ 12:00 pm

    I think MattF's point is that you don't "need rather more equipment" to find out the diameter, vs finding out the circumference. Doing more math is an alternative to more (or different) equipment. Which doesn't change that sticking with circumference might still be the simplest alternative.

  30. Elizabeth Yew said,

    February 19, 2020 @ 12:42 pm

    When I was taking millinery classes at FIT in New York City, I discovered that men's hat sizes were equivalent to women's hat sizes by taking the latter and diving by pi.

  31. Jerry Friedman said,

    February 19, 2020 @ 2:39 pm

    As long as we're doing strange units of area…

    One Circular Mil is a unit of area equal to that of a circle .001" in diameter (.0005" radius). The actual area of a Circular Mil is:

    A =Pi x r²

    A = 3.14159 x (.0005)² inches

    A = .0000007857 square inches

    Circular Mils Explained

  32. ajay said,

    February 20, 2020 @ 6:37 am

    I think MattF's point is that you don't "need rather more equipment" to find out the diameter, vs finding out the circumference.

    I would say that "huge pair of calipers" qualifies as rather more equipment than "bit of string".

  33. Philip Taylor said,

    February 20, 2020 @ 11:29 am

    Re "circular mil"s, while I had never previously known of their existence, I now wonder whether in British English we have "circular thou"s (for /Þ/, not /ð/), since what you call "mil"s we call "thou"s ! A "mil" to me would immediately suggest a millimetre, not a thousandth of an inch.

  34. Ellen K. said,

    February 21, 2020 @ 11:37 am

    Ellen K.:I think MattF's point is that you don't "need rather more equipment" to find out the diameter, vs finding out the circumference.

    ajay: I would say that "huge pair of calipers" qualifies as rather more equipment than "bit of string".

    Ajay, you are missing the point. You don't need the calipers to figure out the diameter. You can do it by figuring out the circumference, and then doing math. The string is sufficient. As MattF says, "you could always measure the circumference and divide by pi". No equipment needed. Which, as I said, doesn't change that it's easier to just not do the math and stick with circumference (I agree with you there), but, nonetheless, if you can measure the circumference, you can figure out the diameter with math.

  35. Rodger C said,

    February 22, 2020 @ 11:41 am

    "you could always measure the circumference and divide by pi". No equipment needed.

    A calculator. Or, for a very long time, pencil and paper.

  36. Philip Taylor said,

    February 22, 2020 @ 3:29 pm

    but between, log tables and then a slide-rule …

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