Catherine, thank you so much for taking the time to answer me. You are
"where the action is." I will be looking forward eagerly to the full
publication, and in the meantime will try to get my public library to get
interlibrary loan copies of the references of reports and proceedings you
provided.

Despite Julia Barrett's helpful post <If there's not a listing of her
research, perhaps you might email or call her directly to request an
overview. I don't want to
volunteer her for the task, but it can't hurt to ask. During the course
of
my work, I've never encountered a researcher who wasn't happy to detail
his
or her research. > I couldn't bring myself to be forward enough to impose
on her for that. I plan to try all other avenues first, and am
disappointed I missed her at ILCA last year, since she won't be at ILCA
this year.

<We are not being told about
> electron microscopic pictures of ductal lumens here. We are being told
> about ultrasound shadows and her interpretation thereof.
I can see ultrasonographers and obstetric sonographers worldwide will be
turning purple over this comment :-) Interpretation of ultrasound images
is
a science which is widely used (and validated) in medical science and
diagnoses.>

Yes, I have no doubt they are! I do have respect for the diagnostic value
of ultrasound. I have borrowed (from our excellent local medical school
library) and perused several fairly recent ultrasound texts from the US
and from Spain. (Not that this makes me any kind of an expert, but I
certainly have more knowledge now than what I had earlier.) I only wish
it were ethical for ductography to be performed on healthy breasts in
late pregnancy and early postpartum to add those findings to the
discussion.

It is likewise seemingly impossible to get (what I believe to be much
more definitive) electron microscope pictures unless we get some forensic
pathologists or breast surgeons interested in following clues in moms
requiring autopsy in late pregnancy or early postpartum, or in moms
recently weaned in order to have surgery for breast pathology or cosmetic
reduction. I respect that ultrasonography is certainly classed as
scientific. But I think that electron microscopy is certainly more exact
at the tissue and cellular level.

I imagine the Australian scholars feel I'm a pretty "cheeky" upstart to
have another interpretation. But it is based on years and years of
palpation of subareolar ducts during late pregnancy and early lactation,
plus having read and re-read literally dozens of articles/text chapters
on the microscopic anatomy of the breasts, complete with electron
microscope pictures and explanations by the histologists and breast
cancer surgeons.

They are the ones who placed the label "lactiferous sinus" in the
official nomenclature of breast tissues, describe it in detail in the
resting (non-lactating) breast, and say it's characteristic appearance
identifies the exact location from which the specimen was removed when
slices of tissue have been taken from the subareolar area. They note that
in adult women the walls in the sinuses contain or are  surrounded by a
very thick layer of elastic tissue. (I am away from my reference to check
for sure) (The sinuses are visible in children and men also, but the
elastic tissue does not appear in those walls.)

It is my suspicion that I am speaking about my experience with
lactiferous sinuses while the elastic fibers in the wall have just begun
to expand as a result of newly formed colostrum gradually being forced
forward. At the stage at which I have done most of my palpation over the
years of literally thousands of mothers during pregnancy and early (3-4
weeks) postpartum, I now theorize that the elastic tissues at that stage
have not yet begun the coiling and uncoiling microscopically
characteristic of elastic strands/tissues when they are repeatedly
expanded and relaxed (as in suckling and/or pumping.)

Compared to the combined decades I spent working on postpartum, prenatal
clinics and in childbirth education/breastfeeding classes assessing
nipple function and teaching hand expression, I have only relatively
recently (4 years ago) begun to volunteer for WIC (the Women Infant and
Children's food education and supplemental food program here in the US),
so I have much less experience hand expressing and identifying sinuses in
mothers who have been nursing for 4 weeks and beyond.

But of those I do remember, I agree that the ducts under the areola are
so soft they are usually not actually palpable as such, other than that
they can be expressed easily with the same placement and movement I use
in earlier lactation. If I use the Marmet method and begin compression
and rolling extrusion deep behind the base of the nipple, the duct ahead
of it can often be felt to "balloon" up ahead of the fingertips as the
milk meets the momentary resistance of the collecting ducts in the nipple
before it squirts out.

None of us have a problem accepting the fact that other reproductive
organs, (vagina, uterus, and even including male organs), undergo changes
in size, texture, turgor, membrane and wall thickness, shape, location,
etc. during various phases of reproduction. In my mind, this is precisely
what is happening here. I feel confident that I have felt slightly
dilated lactiferous sinuses at various random depths behind the areola in
late pregnancy and early postpartum, telling my clients to feel for
something like "little lumps in tapioca". But I can also accept that the
shape and texture of  fully elasticized, extended lactiferous sinuses
during established lactation are probably very well just as Donna has
described.

<I do understand it is
often difficult when only having spoken word and memory available and
that
misinterpretation is more likely then, than when having the written work
to
refer to.>

Yes, it is the "hearsay" I am getting here in the US, (and some
misinterpretation even expressed on LN) that distresses me. The
misinterpretations seem to me to be swirling in wider and wider circles,
like the nursery rhyme of Henny Penny where the main characters are
trying to persuade everybody else by running around crying out "The sky
is falling, the sky is falling!"

Nikki writes << The new Breastfeeding Answer Book has a drawing from
Medela AG, showing a torturous maze of ducts (similar to the capillaries
at the back of the eye)
which makes sense as similar designs repeat in nature.> But to me, that
diagram was very confusing, and if I remember correctly, the publication
is out and out saying, based on this one set of research alone, that we
were formerly 100% wrong about sinuses, etc.

No matter what we in the lactation field choose to label them and believe
about their shape as seen in the unsuckled pregnant or lactating breast,
there are still ducts of some nature beneath the areola within the
subareolar tissues that must be available for extrusion by the infant's
tongue for effective suckling, requiring an efficient latch. "Pulse,
trickle, trickle" is the way I describe to my clients the flow rate
pattern of the breast, in order to explain how it differs from that of a
bottle. The extrusion of the tongue on the subareolar ducts during the
"trickle, trickle" phase I believe is what "empties" those "downstream
ducts" enough to allow them to refill again and again between tongue
motions, partly by gravity as the milk gradually redistributes itself
between MER's.

I do concur enthusiastically with the wider recognition that the
importance of the MER in milk transfer is receiving. I think too many
tend to either take it for granted or ignore it, or are perhaps even
ignorant of it, especially many US hospital personnel and home
visit/pediatric/WIC folks who see mothers early. I feel certain that the
significant others of the mothers I see have seldom been given any
knowledge or insight about it at all. Yet they are the ones likely to be
spending hours with the mother from the time of her hospital discharge
through the crucial days of engorgement and establishment of lactation.
In veterinary literature, it is described as the most powerful force in
milk transfer.

<during a let down there is no separation out of the fat in
milk in the ducts during MER.>

As I said in my original post, I believe that it is between widely
(hours) spaced MER's that the inherent nature of milk to separate into
cream and more and more skim fractions would take place and fat globules
rise toward the ceiling, no matter what position the mother were in. This
would not preclude the ADsorption of the fat globules to the duct walls.
I think it is interesting to note that while myoepithelial cells are
arranged in a basket like pattern around the alveoli, they are present
also on the descending ducts.  But there, they are arranged in a
longitudinal and spiral pattern around the outer walls of the ducts. I
visualize this as producing a sort of peristaltic pattern of contraction
of not only the alveoli but continuing on down the ducts during MER,
which probably is responsible for the temporary shortening and expanded
circumference of the ducts.

There are reports on LN of working mothers too busy to pump early,
perhaps in a stressful work situation with few or no MER's, who by
lunchtime notice the first ounce or so pumped is nearly colorless. If
they are single pumping, of course, by the time they get to the second
side (and a different bottle) they can definitely note the color change
from the mixing effect of the MER they elicited on the first side.

<The diameter of the ducts is consistent with no dilatation of the ducts
where previously "the lactiferous sinuses" were thought to be.>

Can you tell me if any of the mothers were less than 3 weeks postpartum?

<Donna's findings in regard to this
is that the ducts are not used to "store milk" but to transport it. . . .
. . Donna has never suggested that the ducts become empty of milk after a
MER,
just that they resume their pre MER diameter, which necessitates that the
increased volume in the dilated ducts during a MER must "go somewhere" if
the breast is not being fed from or expressed (or is not dripping). >

I have no problem with that, given the further explanation you gave
regarding the diameter of the resting ducts. But even a very small amount
of storage is still storage in my interpretation, meaning it's not a
limited choice between "all or nothing at all". It is my suspicion that
too many are remembering just bits and pieces and interpreting this just
a shade differently, as if it were no longer "all" but now "nothing at
all", or all the way back into the alveolus itself. As I explained, I
cannot believe that that is anatomically or physiologically possible.

<Donna has not been able to visualize alveoli and has not stated that
milk
travels back into the alveoli, only that it travels back into the breast
"towards the alveoli".>

Precisely my point in my original post. I was reacting to Denise's use of
the word "to" instead of "towards". Yet I have no doubt that there were
those that interpreted that to mean "all the way back into the alveoli."

<This may perhaps be in part due
to the action of the muscular sphincter of the nipple, closing off
following
the end of MER (theory only). >

There was a discussion of this on LN once with a reference supplied I
believe by Annelise Bon. This was a veterinary reference, describing that
there are in fact muscular sphinctres somewhere in the teat canal of some
dairy animals. From the detailed reading I have done, I have not yet come
across any references to a "muscular sphincter" per se in the human
nipple, beyond the radial and circular muscles that are apparently
external to the pathway of the collecting ducts which are all located in
the center of the nipple body.

I have reasoned that "this stopping constant leaking function" must be
the reason for the extension from the outside nipple skin surface of the
less expandible squamous epithelial cells lining the walls of the
collecting ducts as they pass inward through the nipple. This type of
cell ends abruptly at the distal end of what the histologists call the
sinuses in the subareolar area, changing to cuboidal or columnar cells,
which are capable of changing their shape (therefore thinning their depth
and expanding their surface area in response to the distention of the
ducts with milk. I envision the change in the shape of the cell to be
like what happens when we smoosh a marshmallow.)

<Incidentally, I have, in the last two weeks, had the pleasure of viewing
the
original 1840 drawings and manuscripts by Cooper (they are magnificent
pieces of meticulous work). . . . . Also the
ductography was done with wax (ie the ducts were injected from the nipple
pores with molten wax to delineate them) probably resulting in the
artifact
of dilation that we subsequently called lactiferous sinuses, and because
of
their structure thought they were storage spaces.>

I had not remembered that he was the one who used the wax. I thought it
was someone else. Do you have any sort of a reference or way that anyone
else might have access to his work? Once again, I believe that unless the
elastic tissue in the walls of the sinuses had already begun to be
stretched and unstretched by weeks of suckling, they would simply be only
partially expanded in early postpartum. I don't think hot wax could
accomplish very much of that alone without rupturing the sinus,
especially on dead tissue. Does the literature identify at what point in
pregnancy or the puerpuerium the mother was?

I agree he must have been meticulous in his preparation of the specimen,
for surgeons tell us the ducts are so integrated with the connective
tissue that it is impossible to dissect them away from each other cleanly
in surgery on the living breast.

I really appreciate your input, and hope others don't feel I am
"cluttering" the list with my questioning statements. Beyond my own
fascination, I believe this is a very very important subject for a
thorough understanding of the complex mother/baby tissue interaction of
suckling. I still believe that it will be a long time till the "jury
verdict" is "in", finally and completely, unequivocally.

Jean
********************
K. Jean Cotterman RNC, IBCLC
Dayton, Ohio (and Phoenix did get its hoped-for rain, 36+ gentle hours of
it.)

             ***********************************************

To temporarily stop your subscription: set lactnet nomail
To start it again: set lactnet mail (or digest)
To unsubscribe: unsubscribe lactnet
All commands go to [log in to unmask]

The LACTNET mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software together with L-Soft's LSMTP(TM)
mailer for lightning fast mail delivery. For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html