Category: Anatomy Lessons

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Anatomy Lesson #51: “The Breast – Male and Female”

WARNING, all anatomy students! Due to some images, this lesson is NSFW. I must confess a bit of trepidation about this topic not only because it is huge but, because it is also ripe for abuse. Hopefully, you will receive this lesson as a public service, as intended. An equal opportunity professor, the anatomy of both male and female breasts is presented. As always, Outlander has a good deal to say about the topic!

FIRST the STATS: Well, there are lots of statistics and none are encouraging: breast cancer is the most common cancer of women both in developed and less developed countries – surprisingly, almost 50% of worldwide breast cancer cases occur in underdeveloped nations. An estimated 12.4% of US and 12.5% of UK women will be diagnosed with breast cancer at some point during their lifetimes. As for the guys: expectations are that one in 1,000 US and one in 870 UK men will be diagnosed with breast cancer during their lives.

Bottom Line: So, why an anatomy lesson on the breast? Understanding breast anatomy can help parents appreciate challenges and rewards of breast feeding and to help male and female patients discuss signs and symptoms of breast diseases as well as treatment options more fluently with health care providers. Useful? I certainly hope so!

Purpose: Based on western culture, one might rightly assume the breast was created to sell merchandise, garner attention, promote discrimination, induce titillation (no pun intended), or sexual arousal. From a biological viewpoint, the purpose of the female breast is for milk production, a process known as lactation…    Sometimes a cigar is just a cigar! ?

Outlander Abundance: Our fav book and TV series often pay homage to both male and female breasts…. equal opportunity entertainers! A quick survey reveals breasts in most Outlander episodes:

  • Jamie: ep 102, 104, 105, 106, 107, 109, 110, 112, 116, 201, 202, 204, 206, 208, 211
  • Claire: ep 101, 102, 107, 108, 109, 110, 204, 206
  • Jenny: ep 102, 114
  • Frank: ep 101, 106
  • Geillis: ep 110, 111
  • Angus: ep 108, 209
  • Rupert: ep 209, 210
  • BJR: ep 116
  • Louise de la Tour: ep 202
  • Dougal: ep 209 (we waited a long time for this one!)
  • King’s mistress: ep 202
  • Suzette: ep 203
  • painted woman at Madam Elise’s brothel: ep 203

Not that I am keeping track <g> but no male or female breasts were shown in episodes 103, 113, 115, 205, 207, 212, 213 (Did I miss any?)!

Diana liberally honors breasts and nipples throughout her works. There are so many examples in the Outlander book series, not enough room to list in this lesson. If I recall correctly, even her spouse once commented something like, “nipples again?” But, I am not complaining!  So, let’s go!

Anatomy of the Male Breast: First the guys!

What better model of the male breast than Jamie? A moment of silence for this fab lad in appreciation for the hard-earned state of his body. With very little body fat, breast contour can be rightly attributed to thorough development of chest muscles (ep 106, The Garrison Commander).

Position: Male breasts sit atop the chest wall (Image A), a sturdy musculoskeletal base including ribs and intercostal muscles (Anatomy Lesson #15, Crouching Grants – Hidden Dagger), pectoralis major and pectoralis minor muscles (Anatomy Lesson #4: Jamie’s Chest – 8th Wonder of the World!). These are layered as follows: pectoralis major is most superficial;  pectoralis minor lies deep to pec major; and, ribs and intercostal muscles (Image A -single arrow) are deep to pec minor.


Image A

Breast Parts: The male breast includes the following parts (Image B):

  • nipple (pigmented elevation)
  • areola (pigmented ring around nipple)
  • ducts (leading nowhere)
  • fat (variable)

Nipple and Areola: Both highly pigmented structures, the areola surrounds the nipple. BTW, areola is pronounced əˈrēələ, not ar-e-o’-la.

Ducts: Ducts (yes, men have them) underlie the nipple and areola but are typically rudimentary and nonfunctional (Image B –  right view).

Fat: The amount of fat in the male breast usually reflects over body fat deposition. Generally, more breast fat accompanies a higher BMI (body mass index).


Image B

Gynecomastia: Of current concern is male gynecomastia, defined as an increase in the size of male breast tissue (Image C). Gynecomastia is triggered by a relative decrease in the amount of testosterone compared with estrogen levels. Although estrogen is considered the female hormone, men normally produce it in small quantities. However, if male estrogens are too high or out of balance with testosterone levels, then gynecomastia may occur.

Infants: More than half of male infants are born with enlarged breasts due to exposure to their mom’s estrogen. This usually resolves within 2-3 weeks after birth.

Puberty: Hormone changes during puberty not uncommonly causes gynecomastia. Again, this usually resolves within 6 months to 2 years.

Men: Prevalence of gynecomastia peaks between 50 and 69 yrs. and may be influenced by many agents which cause glandular tissue to develop from the rudimentary ducts (Image C – right side):

  • various anti-androgen compounds used for cancer treatment
  • some medications for AIDS, heart, gastric motility, and ulcers
  • some anti-anxiety and antidepressant meds
  • some street drugs, alcohol
  • some herbal products
  • aging
  • liver failure


Image C

Male Breast Cancer: Now for a crucial topic no one likes to consider. Many people do not realize men have breast tissue and can develop breast cancer! Breast cancer is a malignant tumor that starts from cells of the breast. Breast cancer cells may grow into (invade) surrounding tissues or spread (metastasize) to distant areas of the body. The following image is a great summary of risks and signs of male breast cancer (Image D)! Please check these out. Many do not realize that like women, men may have a familial disposition to breast cancer. Truth!


Image D

True Story #1: Why do males have breasts? As an anatomy professor, I always champion the position that the body doesn’t have useless structures. Once, a particularly astute student asked in class: “then, why do men have nipples?” Hum….well, I must confess, this kind of stumped me! I pondered the issue and have conclude that men have nipples/breasts for developmental protection. This is my thinking: it is much easier for genetic machinery to produce one sex with fully developed breasts and one sex with underdeveloped breasts than it is to produce one sex with fully functional breasts and the other sex with zip on the chest wall! The latter would add layers of genetic complexity, openly inviting more developmental challenges than our current states of being. Thus, I still hold to my original position! Please feel free to challenge me on this. Je suis prest!

Anatomy of the Female Breast: Now, for the gals!

You might think it only fair that as Jamie is used as the model for the male breast, I will use Claire for the female counterpart. But, I am not going to be fair. Just too intrusive. Sorry to disappoint, but the episodes are listed above for you to view and review! <G>

Location: This goes without saying (but, I will anyway), female breasts are typically more developed than male breasts. But, the relationship to chest wall remains the same: female breasts are superficial to pectoralis major muscles (Image E) and are separated from the muscles by a tough connective tissue layer called fascia.


Image E

Base of Breast: Variations in size, shape, and symmetry of female breasts are the rule, not the exception – even between the breasts of the same person. But, the base of breast, the site where it attaches to the chest wall, is amazingly consistent among women (Image F). The base is located:

  • vertically, 2nd to 6th rib (Image F, between blue dot/dash lines)
  • horizontally, edge of sternum to side of torso (Image F, between red dotted lines)

Try This: Wonder where the 2nd rib is? Place a finger in the suprasternal notch, the divot at the top of your breast bone (Anatomy Lesson #13, Crouching Grants – Hidden Dagger). Move finger downward about 2” (5 cm) until you encounter a prominent bump on the sternum; this is the sternal angle of Louis – and the same level as your 2nd rib. Now, run finger down to tip of the sternum; the 6th rib lies about 1” (2.5 cm) above the tip.

Next, run finger from edge of sternum to midway on your side; this is the horizontal extent of the base of breast. Now, you have a good estimate of the base of breast no matter how large or small the cup size!

Breast Exam: Most women and some practitioners might not know the full extent of breast tissue. A thorough breast exam should explore the full base of breast as well as all remaining breast tissue!

True Story #2: A dear friend found a lump high up by her second rib. A high-grade breast cancer, she is now six years out and doing well as it was caught early and treated aggressively. She now rows in dragon boat races around the world. Moral: check the breast base!

Image F

Parts: Female breasts have the same parts as males with the addition of well-developed glands, ducts and fatty tissues (Image G).

  • nipple
  • areola (pigmented ring around nipple)
  • smooth muscle
  • lactiferous ducts (lead from glands to nipple)
  • mammary glands (drain into ducts during lactation)
  • fat (variable amounts)

Image G

Nipple-Areolar Complex (NAC): NAC is an anatomical acronym for nipple and areola; both are generally well-developed in females.

The nipple is large, (usually) elevated, hairless, and heavily pigmented with melanin (Anatomy Lesson #5, Claire’s Skin – Opals, Ivory, and White Velvet). Nipple skin is thicker than most other skin, designed to resist wear and tear during nursing (Image H). In males and lean or nulliparous (no birth) females, the nipple typically overlies the 4th intercostal space (between ribs 4 and 5) but this is unreliable in women who have given birth at least twice or who have heavy breasts.

The areola (from Latin area meaning “small, open space”) is the region encircling the nipple; it is essentially hairless, slightly raised, thick skinned, and more heavily pigmented than surrounding skin (Image H). The areola usually darkens during pregnancy, retaining the increased pigmentation thereafter. Scattered surface bumps are glands of Montgomery, specialized sebaceous glands (Anatomy Lesson #5, Claire’s Skin – Opals, Ivory, and White Velvet) which release oily substances to water-proof nipple and areola and keep them pliable. Some anatomists posit that the pigmented areola and nipple give the nursing child a target to aim at! Hah!

Jamie is verra knowing about the areolae (pl.). Here from Outlander book:

“That,” I said primly, “is an areola, and you know it, because I told you last week.” “So ye did,” he murmured. “And there’s another one, fancy that.” The bright head dipped to let his tongue replace the finger, then traveled lower.

Thud!


Image H

Smooth Muscle: Finally, the dermis deep to NAC contains specialized bundles of smooth muscle cells (visible by microscopy) – a type of involuntary muscle we studied in Anatomy Lesson #45: Tremendous Tube – GI System, Part 2. Contraction of smooth muscle bundles erects the nipple and tightens the areola. Biologically speaking, this response gives a more substantive bud for an infant to suckle. Nipple erection is managed by the autonomic nervous system, an involuntary response over which even actors have no voluntary control (Starz episode 107, The Wedding)! <GGG>

Supernumerary NAC: This is for fun: humans may exhibit supernumerary NAC. These are typically located somewhere along the milk lines, a pair of lines extending from armpits through breasts, down the abdomen, and ending near the anus (Image I). Animals, such as cats and dogs, have multiple nipples along the milk lines. However, supernumerary NAC in humans can be found pretty much anywhere!


Image I

Apparently, seven celebrities claim to have supernumerary nipples, and purportedly belong to the so-called Triple-Nipple-Club! Snort! Image J, however, is a highly unusual site for a supernumerary NAC (owner unknown). I cannot image that this location would, in any way, prove comfortable or useful other than an entertaining ice breaker at a cocktail party!


Image J

Back to the dissection table!

Lactiferous Ducts: Mammary glands are arranged into 10-20 lobules (small lobes) arranged around the NAC. Each lobule is drained by its own lactiferous duct. All ducts converge near the nipple. Here, each duct expands into a tiny reservoir, a small holding tank for milk to accumulate between swallows by a nursing infant. Again, each duct extends from its lobule to the nipple, resembling the spokes of a wheel (Image K).


Image K

Nipple Openings: Some folks don’t realize that 10-20 ducts open onto the surface of the nipple – each lactiferous duct has its own opening. Years ago when breast feeding was out of vogue (?), old style bottle nipples bore a single opening and peeps who weren’t exposed to breast feeding had no clue that this in no way mimicked the human breast.!

Probably most fans are aware that Jenny was wearing a very convincing prosthesis and pump in Starz episode 114, The Search. This prosthesis illustrates the assumption that a single duct opens onto the nipple, but this is not so.

True story #3: After episode 114 aired, a fan messaged me stating that his wife was breast feeding and human milk doesn’t eject from the breast as it did with Jenny. Actually, it can and does. Breast milk may ooze, drip, or even spurt like a fountain. Truly amazing!

If this info surprises you, dinna fash! Even Nurse Claire didn’t know the female breast can performs such wonders (Outlander book). Diana kens!

“I canna leave the babe for long,” she said in answer to my thoughts, grimacing as she cupped one breast from beneath. “I’ll burst.” In response to the touch, milk had begun to drip from the engorged nipple, thin and bluish. Pulling a large kerchief from her pocket, Jenny tucked it beneath her breast. There was a small pewter cup on the ground beside her, one she had taken from the saddlebag. Pressing the lip of the cup just below the nipple, she gently stroked the breast between two fingers, squeezing gently toward the nipple. The milk dripped faster in response, then suddenly the areole around the nipple contracted and the milk spurted out in a tiny jet of surprising force.

“I didn’t know it did that!” I blurted, staring in fascination.

Forgive Claire, she is a combat nurse and breast feeding is an likely maneuver on a battlefield. I love that Diana doesn’t shy away from the human body with its array of marvelously, messy functions – a courageous example to all. And, ditto to our Jenny actress – remember, no names!

Nipple Piercing: Hum…. I am not a huge fan of nipple piercing, despite its popularity, as the large bore needle used for piercing and hefty nipple rings may cause a strammash with anatomy of the lactiferous ducts (Image L). ‘Nuf said!

Image L

Murtagh, on the other hand, was perfectly fine with Piercing Practices – one of the few times we see Godfather crack a smile (Starz episode 202, Not in Scotland Anymore). Hurry, Murtagh. Back to the Paris apartment and Suzette!!!

Of course, Dragonfly in Amber book says  Jamie’s (not Murtagh’s) eyes were watching the swinging swans!

She was, in current vogue, wearing a gown cut below both breasts… The breasts of “Nesle,” while reasonably adequate in size, pleasant in proportion, and tipped with large brownish areolae, were further adorned with a pair of nipple jewels that caused their settings to recede into insignificance. A pair of diamond-encrusted swans with ruby eyes stretched their necks toward each other, swinging precariously in their gold-hooped perches. The workmanship was superb and the materials stunning, but it was the fact that each gold hoop passed through her nipple that made me feel rather faint. …I felt a presence in my rear and stopped just in time to avoid backing into Jamie, who was watching the King’s mistress with no pretense whatever of tactful obliviousness. “She told Marie d’Arbanville that Master Raymond did the piercing for her,” I remarked under my breath. His fascinated gaze didn’t waver.

Hah! I just bet those bonny blue orbs stayed focused!

Resting Breast: Now, to the nitty-gritty: mammary glands are a specialized type of sweat gland. Yep, ’tis true! A quiescent (non-lactating) breast typically doesn’t have much glandular tissue but that  present is organized into 10-20 lobules, each drained by its own lactiferous duct, as described above. Most bulk of a non-lactating breast is adipose tissue (fat, but adipose sounds soooo much bettah!).

Here’s something really important! Most breast illustrations inaccurately show glandular tissue evenly distributed around the NAC (Image M). And, old-style breast implants look like half a baseball pushed under the skin, which is also incorrect! These appear odd to the eye because the natural breast is tear-drop shaped: outer and bottom breast borders are well-defined, but inside and top borders slope from chest wall toward the NAC, producing to the tear-drop shape. More importantly, breast glands are also distributed in a tear-drop configuration!


Image M

Axillary Tail: Breast glands do surround the NAC, but a tail of glandular tissue extends up towards the axilla (armpit), the so-called axillary tail of Spence (Image N). Divide the breast into four quadrants and see the glandular tail extends from the upper outer quadrant toward the axilla. Ergo, like the base of breast, this area must be included in a thorough breast exam! This is why mammography technicians work very hard to mash and smash the entire breast between those plates!

Try this: On yourself or a willing (very important!) female partner, grasp the anterior axillary fold (Anatomy Lesson #4, Jamie’s Chest – 8th Wonder of the World), this fold of pectoralis major muscle lies just in front of the armpit. Feel the flesh overlying this fold – the axillary tail is in the overlying flesh. Breast tissue feels slightly bumpy-lumpy under the fingertips. Confirm its continuity with the rest of the breast tissue.  This is the axillary tail. Good job!

Image N

Fat and Connective Tissue: The female breast typically contains fat insinuated between gland lobules and ducts (Image O) – the amount is highly variable. In a quiescent breast, most of its size is dictated by fat deposits and these are regulated by hormones because fat is required to convert precursor molecules into estrogens.

Fat, ducts, and glands are supported by the suspensory ligaments of Cooper. Suspensory, my sporrin! These dinky strands of collagen should never share the same name with those splendid, stout bands of collagen lending integrity to most of our joints! Typically, the suspensory ligaments are so wee and weak, they can barely be found during dissection! Believe me, they are much thinner than Image O suggests. And, they offer basically zip support for larger breasts!


Image O

Active Mammary Glands: During pregnancy, three hormones (estrogen, progesterone, human placental lactogen) stimulate breast gland growth. Rapid gland grown arising from the lactiferous ducts and enhanced fat deposition account for a dramatic increase in breast size (Image P) when a little one is in the oven. Imagine the budding of blossoms from a tree branch as a splendid analogy to gland development of the breast!

After birth, progesterone and estrogen levels fall and the anterior pituitary gland releases the hormone, prolactin, stimulating the breast to produce milk.

Lactating mothers often experience the “let down” reflex, a tingling, tightening, or warm feeling in the breasts after an infant begins to suckle. Once conditioning sets in, some moms just think about nursing her child, and down the milk comes! This response occurs because another hormone, oxytocin, released from the posterior pituitary gland, targets specialized cells around lactiferous glands and ducts. Oxytocin causes these specialized (myoepithelial) cells to contract which moves the milk along the duct system towards the NAC (Image N – right panel). This amazing process is clearly designed to ensure our young are effectively nurtured.


Image P

Breast Lymphatics: I have yet to write a lesson about the amazing lymphatic system. So, in a nut shell, almost all body tissues (a few exceptions) are riddled with lymphatic vessels which collect fluid escaping from small blood vessels. Next, the fluid enters lymphatic vessels as lymph and is subsequently returned to the blood vascular system. This cooperation between two circulatory systems prevents our tissues from swelling with too much accumulated fluid.

Male and female breasts are riddled with lymphatic vessels (Image Q; male shown in Image B ), draining lymph towards arm pit or top of chest or crossing to the midline. Along the way, lymph percolates through several groups of lymph nodes.  These tiny organs contain protective cells which surveil the fluid, removing undesirables (cancer cells, pathogens, foreign matter, etc.) from the lymph. They also help mount immune responses to destroy unwanted antigens in the lymph.

Although this design ensures that excess fluid is removed quickly and efficiently, especially during lactation, it also allows for metastases of breast cancer. Cancer cells love to jump ship and enter the lymphatics. If they escape surveillance by protective cells of lymph nodes, they continue to hitch a free ride spreading to other body sites.


Image Q

Female Breast Cancer: Returning to this unhappy but crucial topic, the female breast exhibits more signs and symptoms of this dreadful disease because it is more developed (Image R)! Unfortunately, the eight signs shown in Image R tend to appear rather late in the course of a cancer. You should also know that breast cancer isn’t one disease; there are at least five main types with several grades among the types. Thus, it is crucial that women perform self-exams and get breast checks on a regular basis. Please be aware of these signs, be vigilant, and follow your health care professional’s guidelines! (BTW, peau d’ orange means “orange peel skin”)

True Story #4: Many men and women who experience open breast biopsies may wait many days for a path report and diagnosis. I worked with a pathologist, board certified in FNA (fine needle aspiration), who specialized in diagnosing breast disease. He pushed a cart loaded with stains, microscope, etc., into the room of his patient; aspirated the lump with a needle, prepared the specimen, viewed it under the microscope, and gave the patient a diagnosis on the spot. No agonizing waiting. No scar. If you are told you need a biopsy, think about requesting a FNA.


Image R

OK, anatomy of male and female breasts is done. Time for a wee bit more fun!

True Story #5: Recently, a reader asked me why breasts appeared so high and rounded as seen with many Outlander costumes. I think she intends something like Claire’s glorious wedding dress (Starz episode 107, The Wedding) –  the one for her marriage to Jamie, not the 40’s suit she wore to marry Frank! This appearance doesn’t occur because breast anatomy somehow morphed over 200-300 years; breasts assume this shape because of the corset!

Recall this scene (Starz episode 102, Castle Leoch)? After much grunting, huffing, and puffing, Mrs. Fitz trusses Claire up like a Christmas goose! Comfortable,  Sassenach lass? I shouldna think so!

Diana explains in Outlander book:

Brooking no protests, the dame bustled me out of my inadequate garments and oversaw my dressing from the skin out. She stood back, surveying her handiwork with satisfaction.

In the episode, Claire modestly removes her  “French brassiere” and panties under the disapproving eyes of Mrs. F! They were replaced with bum roll, shift, and corset, which flattens the breasts, because it has no cups.

Even Laoghaire gets into (erm, almost out of) the act… (Starz episode 109, The Reckoning) – her goose flesh literally honks! And, I want to know how those laces made their way to the front of her corset? And where did she find it? Bet granny Fitz didna ken Laoghaire was into Castle Leoch’s fab closet! Grrrrr! (Love the actress, though!).

I am not a costumer and I may hear back from those who are. But, I believe 18th century corsets usually covered the breasts (or barely did, as with the teen trollop), or ended under the breasts, or had primitive, sewn-in cups. A corset like Claire’s was typically laced as tightly as possible, flattening breasts against chest wall. Where does a healthy breast go? Well, having little choice, it pops up over the corset top, hence the robust (Get it? – robust?) effect of Claire’s gorgeous wedding gown!

If the waist was laced tightly, an hour-glass figure emerged, highly desirable, especially in the 1800s (Image S)! But, that squeeze was pretty rough on rib cage and internal organs….which brings me to the next story!

True Story #6: When I was in graduate school, my anatomy professors claimed that 18th and 19th corsets compressed internal organs so much that, upon autopsy, the livers of some women were permanently grooved by compression against the ribs. You get the idea in Image S. A good story, but one I have not been able to confirm as true or false.


Image S

Thus ends the fascinating saga of human breast anatomy. Darn! Wasn’t it interesting?  Do we now understand the basic anatomy of male and female breasts? Hopefully, yes, but this is unlikely to alter their rather universal appeal!

Let’s close with an evocative, contemporary ode to her breasts. Written in June of 2015, apparently, it is based on a true story!

Her Breasts (Mammary Memory)
by Joe Cottonwood

The white-haired doddering gentle old man
in the crushing silence of the public library
blinking through spectacles
writes with shaking hands
in a pocket notebook
unaware that he is muttering to himself:
Her breasts… her breasts…

Eyes peer over books.  Pencils pause,
except the old man’s.  Fingers
mark pages.  We await,
expectant, puzzled.  He has pulled a dusty volume
from the shelf of his memory
and still writing, whispers, hissing:
Her breasts…

I want to know: was it in moonlight?
Hurried?  Forbidden?
Dear woman, take joy that after half a century
not only your lover but a whole reading room
of men and women are sharing — are in awe of —
your stunning warmth:
Her breasts!  Her breasts!

A deeply grateful,

Outlander Anatomist

Photo Creds: Starz, Gray’s Anatomy for Students, Drake, Vogl and Mitchell, Elsevier, 2005 (Image H), www.bolatitoblog.com (Image R), www.cambridge.org (Image A), www.cancer.gov (Image B), www.cancerworld.info (Image D), www.causticsodapodcast.com (Image J), www.diariosanacronicos.com (Image S), www.healthtype.com (Image E), www.komennyc.org (Image K), www.decodedscience.org (Image G), www.mayoclinic.com (Image C), www.quora.com (Image P), www.reddit.com (Image I), www.slideshare.net (Image F), www.studyblue.com (Image N; Image O; Image Q), www.theronion.com (Image L), www.what-when-why-how.com (Image M)

 

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Anatomy Lesson #50: Care for us – Oh Pancreas!

Tommy Lee Jones, starring as Hawk Hawkins in Space cowboys (2000), said it best (Image A):

Where the hell is the pancreas, anyway?  I don’t even know what the damn thing does beside give you cancer!

Terrific question, Hawk! Welcome anatomy students to Lesson #50, the pancreas. Our goal today is to answer Hawk’s question and more: what is the pancreas, what does it look like, where is it located, what does it do, and what diseases plague it?

This is the 7th and final lesson of the immense gastrointestinal tract and associated organs! Turns out, pancreas is one of these “Klingon” organs.

Although Diana hasn’t written a great deal nor has Starz episodes showed much about the pancreas, there are bits and pieces here and there. As always, these are scattered throughout the lesson. I hope you find the pancreas as compelling as your body does. Off we go!

space cowboys movie poster
Image A

History: Herophilus (335-280 BCE), Greek anatomist and surgeon (Image B), helped found the ancient school of Medicine in Alexandria, Egypt. He also championed human dissection and was the first to describe the pancreas. Students may recognize Herophilus because he also featured in Anatomy Lesson #34, The Amazing Saga of Human Anatomy.

Image B Herophilus

Gross Anatomy: The word, pancreas, comes from the Greek pan, meaning “all,” plus the Greek kreas, meaning “flesh;” so, “all flesh.” A seemingly odd term until one views the pancreas and then, it seems sensible as it appears markedly fleshy, soft, and squishy (Image C).

pancreas
Image C pancreas

Outlander Fix #1: Answering Hawk’s first question, “Where the hell is the pancreas, anyway?”, Mary-Mary-Quite-Contrary knows (Starz episode 211, Vengeance is Mine). Or, rather, Mary’s Knife-Knows! Och, lass, that is Jamie’s dirk. Careful! Verra sharp!

mary holding a knife in outlander episode 211
The dirk finds it’s mark, pretty much where the pancreas lives! A grim ending to a vicious valet. And he isn’t the only one taking a hit from a blade in this episode. Written by our own beloved Diana, this gratifying chapter brings some very bad players to their just desserts (Starz episode 211, Vengeance is Mine), although that mad bastard captain remains at large. Come on S.3!

image of a man being stabbed from outlander episode 211

On to anatomy!

Pancreas Location: The pancreas (Image D) lies in the upper abdominal cavity behind the stomach (Anatomy Lesson #46: Splendid Stomach, Wobbly Wame). Oriented almost horizontally, it extends from the curve of duodenum to the spleen, a distance of some 6” (15 cm). In this position, it contacts stomach, spleen, duodenum, colon, jejunum, bile ducts, and major intestinal blood vessels. Pillowed among other soft abdominal organs, its location is pertinent, especially in pancreatic cancer as we shall shortly see. It lies between T12 and L2 vertebral levels.

Try this: Place thumb on the xiphoid process (tip of sternum – Anatomy Lesson #15: Crouching Grants – Hidden Dagger) and little finger of the ipsilateral (same) hand on your umbilicus. The xiphoid process is located at T9-T10 vertebral levels; the umbilicus at L3-L4. Now, place a finger of the contralateral (opposite) hand midway between xiphoid and umbilicus – this is the approximate vertebral level where your pancreas dwells. These new terms are thrown in to enlarge your anatomy vocab!

 

image of the pancreas
Image D

Divisions: Although many sources describe three divisions of the pancreas, it actually has five: head, neck, body, tail, and uncinate process (Image E). The head tucks into the C-shaped curve of duodenum. A short neck lies between head and body. The body supplies most of its 6” length. The tail tucks into the spleen (review Image D). The uncinate process (Latin meaning hook-shaped) is the smallish part that tucks in behind some large blood vessels of the gut.

You might consider these segments as rather arbitrary, but they are very useful in localizing disease entities, particularly pancreatic cancer.

image of the parts of the pancreas

Image E

Gland: The pancreas is an organ but it is also a gland meaning it produces and releases secretions (products). It is also a mixed gland meaning it it is both exocrine and endocrine gland. Now, most glands are either exocrine or endocrine in type, but the pancreas is unusual because it is both.

Exocrine: Exocrine glands release products into ducts which carry the secretions to a destination. In this case, pancreatic exocrine secretions flow into the pancreatic duct (Image F) which joins the common bile duct (Anatomy Lesson #49, Our Liver – The Life Giver!) before entering the duodenum. Pancreatic exocrine secretions include an array of enzymes that digest various dietary substances, including:

  • carbohydrates
  • lipids (fats)
  • proteins
  • nucleic acids (DNA, RNA)

Finally, the duct system draining the pancreas produces bicarbonate to help neutralize acidic foodstuffs released by the stomach into the duodenum (Anatomy Lesson #46, Splendid Stomach, Wobbly Wame).

Image F

Endocrine: Endocrine gland secretions are picked up and distributed throughout the body by the blood stream –  no ducts involved! And most of such secretions are classified as hormones or hormone-like substances. The pancreas produces its hormones via small spherical islands of cells formally known as pancreatic islets of Langerhans (brilliant German pathologist). About 3 million tiny islets (Image G – violet clusters) are scattered throughout the pancreas although more are concentrated in the tail region.  Their combined mass is only about 2 grams (.0022 pounds). Yet, their effects in the body are profound!

These tiny clusters contain five different types of cells, producing the following compounds:

  • glucagon (stimulates cells to release glucose – raises blood sugar levels)
  • insulin (causes cells to absorb glucose – lowers blood sugar levels)
  • somatostatin (regulates release of glucagon and insulin)
  • pancreatic polypeptide (regulates intestinal function)
  • ghrelin, the “hunger hormone” (regulates appetite –  pancreas produces small amounts of this compound – stomach is major source)

Image G

Outlander Fix #2: Yay! Claire fixes her mind on her pancreas in Dragonfly in Amber book. Yep, she does! (Psst…the image is from their Paris days – Starz episode 203, Useful Occupations and Deceptions – not from Lallybroch.)  Not a perfect match with the quote, but Claire in bed is always good, especially if Jamie is nearby. Dinna ken how Claire’s mind fixes around her pancreas, but I do trust the lass! <g>

As I began to hover on the edge of sleep, my mind fixed somewhere around my pancreas, I could dimly hear the sounds of small Jamie pattering down the hall to his mother’s bedroom—roused from sleep by a full bladder, he seldom had the presence of mind to take the obvious step, and would frequently blunder down the stair from the nursery in search of assistance instead.

image of Jamie and Claire in bed
Buh-bye Claire – Thank you for the pancreas lesson!

Microscopy: Exocrine and endocrine pancreas are readily differentiated by microscopy. Bear with me, folks-without-training-in-microscopy, as I explain. Image H is a thin slice of pancreas stained with dyes (H&E).  The red globs are pre-enzymes inside deep purple exocrine cells. After release as enzymes, they enter the pancreatic ducts and are transported to the duodenum. The pale violet blob in the center is a pancreatic islet of Langerhans. This blob contains tiny purple ovals, nuclei of the five different cell types mentioned above; collectively, these islets form the endocrine part of the pancreas. In 3-D, the pale blob is spherically- shaped.

This exercise is important to explain how anatomical pathologists diagnose disease. They learn to recognize normal pancreas (and all other organs) in the microscope. This enables them to determine if a tissue sample lies outside that expectation and, if it does, what disease does it best match. This ability is called pattern recognition. Got it? Grand!

Image H

Diseases: Like other organs, the pancreas has its own palate of diseases and many have devastating effects. There are three major players:

  • Pancreatitis: means inflammation of the pancreas. Acute and chronic types. Most common cause is alcoholism. Its own enzymes start digesting pancreatic tissue – Painful!
  • Diabetes mellitus: Types 1 and 2 interfere with sugar (glucose) uptake by body cells, although causes are different.
  • Pancreatic cancer: one of the more infamous cancers, it has a very low survival rate – overall five year survival rate is only 7%.

Outlander Fix #3: Claire’s own words from Dragonfly in Amber book inform us of a L’Hôpital des Anges’ patient with sugar sickness (Type 1 diabetes). Starz episode 203, Useful Occupations and Deceptions, faithfully brings Diana’s lines to life!

I bent over a pallet at the edge of the floor. A very thin woman lay listlessly under a single blanket, her eyes drifting dully over us without interest.

It wasn’t the woman who had attracted my attention, so much as the oddly shaped glass vessel standing on the floor alongside her pallet. The vessel was brimming with a yellow fluid—urine, undoubtedly.

psssst: The oddly shaped glass vessel used in the episode is an Erlenmeyer flask. It wasn’t invented until 1861 <g>

I was mildly surprised; without chemical tests, or even litmus paper, what conceivable use could a urine sample be? Thinking over the various things one tested urine for, though, I had an idea. I picked up the vessel carefully, ignoring Sister Angelique’s exclamation of alarmed protest. I sniffed carefully.

Sure enough; half-obscured by sour ammoniac fumes, the fluid smelled sickly sweet—rather like soured honey. I hesitated, but there was only one way to make sure. With a moue of distaste, I gingerly dipped the tip of one finger into the liquid and touched it delicately to my tongue.

…Sister Angelique was watching with sudden interest. … “Are you thirsty, Madame?” I asked the patient. I knew the answer before she spoke, seeing the empty carafe near her head. “Always, Madame,” she replied. “And always hungry, as well. Yet no flesh gathers on my bones, no matter how much I eat.” She raised a stick-thin arm, displaying a bony wrist, then let it fall as though the effort had exhausted her.

I patted the skinny hand gently, and murmured something in farewell, my exhilaration at having made a correct diagnosis substantially quenched by the knowledge that there was no possible cure for diabetes mellitus in this day; the woman before me was doomed.

In subdued spirits, I rose…“Could you tell from what she suffers, Madame?” the nun asked curiously (Mother Hildegarde in the Starz episode). “Only from the urine?” “Not only from that,” I answered. “But yes, I know. She has—” Drat. What would they have called it now? “She has … um, sugar sickness. She gets no nourishment from the food she eats, and has a tremendous thirst. Consequently, she produces large quantities of urine.” … “And can you tell whether she will recover, Madame?” “No, she won’t,” I said bluntly. “She’s far gone already; she may not last out the month.”

Is Jamie please with Claire tasting urine and treating scrofula? Noooo….he doesn’t want his pregnant wife messing with piss and pus! Och!

History of Diabetes Mellitus: Diabetes was described three millennia before Claire sampled her patient’s urine. About 1500 BCE, Sushruta, the Indian physician, wrote the first description of diabetes mellitus, noting that ants and flies were attracted to the urine of people with a mysterious disease causing intense thirst, enormous urine output, and wasting away of the body.

In 250 BCE, Apollonius of Memphis (Egypt), coined the term diabetes meaning “I pass through.” Later, mellitus, Latin for “honey-sweet,” was added to emphasize the sugar content of the urine and to distinguish diabetes mellitus from diabetes insipidus, a disorder of the pituitary gland also characterized by intense thirst and high production of urine.

Finally, the Greek physician, Aretaeus (Image I) wrote this description in the second century AD:

“Diabetes is … not very frequent … being a melting down of the flesh and limbs into urine … for the patients never stop making water, but the flow is incessant, as if from the opening of aqueducts. It consists in the flesh and bones running together into the urine … the illness develops very slowly. The nature of the disease is chronic, and it takes a long period to form; but the patient does not live long once the disease is fully established; for the melting is rapid, the death speedy. Moreover life is disgusting and painful; thirst, unquenchable … and one cannot stop them either from drinking or making water”.

Image I

Simple Physiology: Our bodies contain millions of cells. These cells use glucose to make energy for our daily activities: heartbeat, muscle contraction, fighting redcoats. Snort! How do cells get glucose? When you eat or drink, food is broken down inside the gut into simple proteins, lipid components, and sugars, mostly glucose. Glucose enters the bloodstream and circulates. Although circulating glucose contacts body cells, they cannot absorb it on their own.

So, circulating glucose stimulates pancreatic (beta) islet cells to release insulin into the blood stream. Insulin circulates with the glucose and acts as a key to permit body cells to absorb glucose. No matter how much glucose circulates in the bloodstream, insulin is required for it to enter the cells: no insulin – no glucose uptake! The following brief  You Tube cartoon illustrates the process very well.

http://youtu.be/OYH1deu7-4E

Oh, and just so you ken, insulin produces 9 effects in the body. Glucose uptake is only one of these.

I like this cute T, but it is slightly misleading. The pancreas doesn’t really ask for sugar. Rather, pancreatic cells check blood glucose levels and as those levels rise, it releases insulin to induce body cells take in sugar. If glucose blood levels fall below normal, then the pancreas releases glucagon which mobilizes stored glucose for released into the blood stream. A very clever check and balance system.


Image J shirt

Type 1 (I) Diabetes Mellitus (DM): Simply put, Type 1 DM is a chronic condition wherein the pancreas produces little or no insulin so glucose cannot enter cells. Instead, glucose stays in the bloodstream, spilling into the urine, and pulling water with it; hence, the continuous thirst and high urine production (polyuria). Even today, there is no cure for Type 1 DM but it can be managed, usually with daily doses of insulin.

The exact cause of Type 1 DM remains unknown despite decades of intense research. In many, the body’s own immune system mistakenly destroys insulin-producing (beta) cells of the pancreatic islets. Both genetics and viral infections appear to play important roles in the development of diabetes.

Type 2 (II) DM: Type 2 DM occurs when the pancreas doesn’t produce enough insulin or cells are unable to recognize the insulin and use it properly, a state known as insulin resistance. Insulin resistance is the most common cause of Type 2 DM. Here, genetics and lifestyle are important risk factors. According to the US CDC, obesity and lack of physical activity are responsible for 95% of Type 2 DM in the US!

Pancreas Transplant: Yes, these surgeries are done. A pancreas transplant is a surgical procedure to place a healthy pancreas from a deceased donor into a person whose pancreas no longer functions properly (Image K). Most transplants are done to treat Type 1 DM, and, occasionally for Type 2. Although a transplant offers a potential cure for DM, it is generally reserved for folks with serious diabetes complications because the side effects of a pancreatic transplant are significant.

The donor pancreas plus the segment of duodenum that receives the pancreatic duct are transplanted into the cecum of the large intestine (Anatomy Lesson #48, The Big Guy!). So, the recipient then has a pelvic pancreas. Such surgeries must be disclosed to new health care professionals so they are aware of unexpected changes in typical anatomy.


Image K

Pancreatic Cancer: Many of us have lost a family member, friend, or acquaintance to pancreatic cancer. This type of cancer is often detected late, spreads rapidly, and has a poor prognosis. Why? Unfortunately, early stages of this cancer are mostly asymptomatic. Later stages are associated with symptoms, but these can be non-specific, such as lack of appetite and weight loss. So, the cancer may be advanced before detected.

Pancreatic cancer is staged 0-IV depending on its spread (Image L). Early in this lesson, we learned that the pancreas is in contact with duodenum, jejunum, colon, spleen, stomach, bile ducts, and blood vessels, providing many opportunities for metastases. Also, these surrounding organs are soft, so a spreading cancer has considerable space to grow before creating an organ stramash.

As you might assume, the prognosis is better for those whose pancreatic cancer is diagnosed at an early stage. The median survival rate after diagnosis and medical treatment is still abysmal: only 6 to 12 months. Let us be grateful it isn’t one of the three most common cancers.

True story: one of my neighbors was diagnosed with pancreatic cancer in the 1960’s. She survived a Whipple procedure, a.k.a., pancreaticoduodenectomy, which is why it is called a Whipple! This horrific surgery removes head of pancreas, duodenum, gallbladder, part of common bile duct, and part of stomach. She was a lucky lady who raised three sons and survived into her 80’s!

A possible piece of good news: New Scientist magazine (15 April 2017) reports that, by chance, a drug used to treat strokes has been found to significantly prolong the lives of mice with pancreatic cancer. Turns out, pancreatic cancers are protected by a capsule of connective tissue that acts like a coat of armor. Australian researchers found the stroke drug, fasudil, weakens the capsule, making it easier for chemotherapeutic agents to reach the tumor. Drug trials in humans are planned. Fingers crossed!


Image L

Let’s close this lesson on a happier note with Culinary Considerations.

Sweetbreads or Sweet breads??? Let’s get this out of the way, right now! Sweetbreads are thymus and pancreas (and, often salivary glands). Yes, people eat pancreas (Image M), gah! I canna like this as I have met too many of these organs on the dissection table. To me, sweetbreads are Awful-Offal! They do enjoy legions of fans, so dive in, if they work for you. You can have my share <G>


Image M

On the other hand, sweet breads (Image N) are verra hard to resist, especially the homemade variety.  Yummy, yummy, yummy, in my tummy, tummy, tummy! ‘Nuf said!


Image N

Let’s give the last word to American poet Robert Frost because he was creative enough to write a poem about sweetbreads.

Quandary

You drive me to confess in ink:
Once I was fool enough to think
That brains and sweetbreads were the same,
Till I was caught and put to shame,
First by a butcher, then a cook,
Then by a scientific book.
But ’twas by making sweetbreads do
I passed with such a high I.Q.

Dear Robert: the butcher, baker and candlestick maker – och! -butcher, cook, and science book are correct! Sweetbreads dinna include brain!

A deeply grateful,

Outlander Anatomist

Photo Creds: Starz, www.123rf.com (Image E pancreas parts), www.blog.kingarthurflour.com (Image N sweet breads)
www.cancer.gov (Image D pancreas site), www.dypatil.edu (Image B Herophilus), www.en.wikipedia.org (Image I Aretaeus), www.fanart.tv (Image A Space Cowboys), www.healthtop.com (Image C pancreas), www.mayoclinic.org (Image K pancreatic transplant; Image L Pancreatic Cancer), www.medicalwork.com (Image G pancreas mixed gland), www.medievalspanishchef.com (Image M sweetbreads), www.pancreatic.org (Image F pancreas ducts), www.shutterstock.com (Image H pancreas histo), www.threadless.com (Image J shirt)

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Anatomy Lesson #49, “Our Liver – The Life Giver!” – GI Tract 6

Hallo, anatomy students! Welcome to Anatomy Lesson #49, Our Liver – The Life giver. We finished our exploration of the GI tract proper (lips through anus), and today, we continue with associated organs of the GI tract. In former lessons, we learned that during embryonic development, various organs arise as outgrowths of the gut tube (Anatomy Lesson # 44, “Terrific Tunnel – GI Tract I”). Such organs retain these connections throughout life, so their products flow via ducts (tubes) into the GI tract proper.

Liver is on our docket today. Liver develops during intrauterine life as an outgrowth of the nascent gut, retaining its attachment via a system of hepatic ducts. And, as the title correctly states, liver is a “giver,” not a “taker.” Liver is the type of “anatomical“ personality we crave in our lives, as it is the seat of many life processes!

As always, this lesson sports Outlander images and quotes about liver. What? Are there really liver quote from our fav books and TV series? Indeed, there are!

Word Origin: Liver, is an Anglo-Saxon word (1325) for liv-er or lifer. Logically, the etymology for liver infers “life,” although the original intent is lost. The name is apt, though, because many vital life functions occur therein. And, our very busy liver has insinuated itself into history, prophecy, character, culture, horror, mythology, and medicine!

History: Greek physician, Claudius Galen (130-200 CE), anointed liver as the principle organ of the body, teaching it as the primary source of blood and lymph (Anatomy Lesson #34, The Amazing Saga of Human Anatomy) – a status enjoyed for 1500 years! After this was disproven, liver fell from grace (sad face), only to have its stature revived in the 19th century by French physiologist, Claude Bernard. Bernard showed the liver serves many vital functions; indeed, we now know of at least 50 ways (TY, Paul Simon), to “love your liver” (Image A). But, counting all known liver functions, its duties approach 500!

Image A

Prophecy: Ever thought of a liver as a crystal ball? Believe it or not, livers were used for divination. Ancient Babylonians (19th century B.C.) studied sheep livers as a means to foresee the future. Such findings were documented on clay tablets in the shape of a sheep’s liver, complete with surface markings used for prophesying and instruction (Image B).

 

Image B

Character: The liver has the dubious honor of being used to symbolize a number of less savory human attributes, such as:

  • lily-livered (cowardice)
  • chopped liver (worthless)
  • white liver (cowardice)
  • hard liver (sensualist)
  • liver-hearted (craven)
  • liver-faced (mean-spirited)
  • liver-lipped (pale and feeble)
  • liver-sick (dropsy = cirrhosis or hepatitis)

Our beloved Outlander provides stellar examples of several such liver characteristics:

That lily-livered (coward), dastardly Duke (Starz, episode 110, By the Pricking of My Thumbs) peeks from behind a tree, leaving Jamie to battle three grumpy MacDonalds! Mayhap they only got haggis for brekky?

I think that I shall never see,

A more cowardly knave behind a tree!

From the same Outlander episode (Starz, episode 110, By the Pricking of My Thumbs), liver-faced (mean-spirited) Laoghaire spies Claire being arrested for witchcraft. She will happily sling the Heiland fling on Claire’s still-warm ashes!

I think that I shall never see,

A more wicked lass brimming with glee!

Now, please dinna fash, I affront the character, not the gifted and beautiful actress!

And before we leave Character-Assassination by liver, consider the hard-livered (sensualist), Black-Jack. A sociopathic-psychotic-sensualist if ever I saw one (Starz, episode 116, To Ransom a Man’s Soul)!

I think that I shall never see,

A more depraved voluptuary than HE!

Culture: Many cultures offer idioms about the liver. This “pointed” one is an ancient Tibetan Proverb: My enemy’s liver is the sheath of my sword!

Och! Jamie and his men present a perfect metaphor for this dire warning, with raised blades at the Battle of Prestonpans (Starz episode 210, Prestonpans). Redcoat livers: take care and beware – your livers willna be living long!

I think that I shall never see

a more deadly blade than…Owie!

Horror: The liver appears in a surprising number of “settings and upsettings” to convey horror!  Jonathan Demme’s 1991 horror film, The Silence of the Lambs offers a perfect example:

Check out this link to YouTube for a peek at this creepy scene!

Liver, fava beans, and a nice Chianti? Yuck. Well, maybe the nice Chianti. Hilarious Hannibal – the life of the party!

Anthony Hopkins as Dr. Hannibal “The Cannibal” Lecter in the 1991 film “Silence of the Lambs.” Photo Courtesy: MGM Home Entertainment

Mythology: Let’s not forget myths! Liver was immortalized in Theogony, a poem by Hesiod (8th – 7th century BCE), wherein the fate of the Titan, Prometheus (no relation to Ridley Scott), is recorded. Much to Zeus’s fury, Prometheus unwisely granted humans the gift of fire and the skill of metalworking. Zeus was so pissed, he chained Prometheus to a mountain rock. Immortalized in this stark painting (Image C), each day, Zeus sent an eagle to eat Prometheus’ liver and every night, his liver regenerated only to be devoured the next day. Eternal retribution (Prometheus eventually escapes)! Lesson learned: Yo mama always said, “dinna play with fire!”

Image C by Ruben and Snyders

 Medicine: Many cultures have used liver as medicaments. Even today, cod liver oil is taken to lower high triglycerides and high blood pressure, and to treat some symptoms of diabetic-related kidney disease (www.webmd.com).

An 1899 book titled “Animal Simples,” by W. T. Fernie, M.D., states:

Dr. Heffinger advocates the taking of crocodile liver oil for phthisis; which almost supersedes the use of cod-liver oil in Peru; being more nourishing and palatable.

I dinna ken Dr. Heffinger, but I assume and presume he was a renown practitioner of 19th century medical arts. Oh, and phthisis is an old term for pulmonary tuberculosis, although liver oil likely had zero effect on this diabolical disease.

We encounter crocodile oil at Master Raymond’s Paris apothecary shop (Starz, episode 204 La Dame Blanche)! This “little shop of horrors” (snort!) displays pretty much every oddity in gay Paree! There’s even a quote from Dragonfly in Amber book:

“My crocodile ? Oh, to be sure, madonna. Gives the customers confidence.” He jerked his head toward the shelf that ran along the wall just above eye height… Three of the jars closest to me were labeled in Latin, which I translated with some difficulty—crocodile’s blood, and the liver and bile of the same beast, presumably the one swinging sinisterly overhead in the draft from the main shop

“never smile at a crocodile…..”

Gross Anatomy: OK, enough  socializing – time for gross anatomy. Yay! Here, gross means visible with the naked eye (Anatomy Lesson #34, The Amazing Saga of Human Anatomy); it does not mean yucky!

Location: Where, oh where, does the liver dwell? It lives in the abdominal cavity along with most of the GI tract. Its location is best defined by dividing the abdominal wall/cavity into imaginary quadrants (Image D); vertical and horizontal lines intersect at the umbilicus (Anatomy Lesson #16, Jamie’s Belly or Scottish Six-Pack), dividing the area into RUQ, LUQ, RLQ, and LLQ.

Most of the liver resides in the RUQ although some extends into the LUQ. There’s another anatomical method dividing abdominal cavity and wall into 9 segments but the quadrant system works best for today.

Image D

Respiratory Diaphragm: What does respiratory diaphragm have to do with liver? Lots! Anatomy Lesson #15, Crouching Grants – Hidden Dagger, taught that the respiratory diaphragm is parachute-shaped, doming upwards such that it is largely surrounded by rib cage, sternum, and vertebrae (Image E).

Image E

Anchorage: Liver abuts the respiratory diaphragm (Image F – hooks) but it doesn’t flop around in the RUQ. Rather, it is anchored in place by membranes (Image F – red arrows), layers of peritoneum which bind liver tightly to the diaphragm.

Image F liver

Ribs and Sternum: Because the liver abuts the respiratory diaphragm, it too, enjoys the immediate and privileged protection of sternum, ribs and vertebrae (Image G). As such, a normal liver is challenging for a practitioner to palpate. To do so, a patient lies on the back and inspires deeply; the practitioner presses fingers under the right costal margin and, if skilled, may be able to feel the margin of the liver slip under the fingers. Normal liver is soft, smooth and slightly tender to palpation. An easily palpated liver is usually associated with one of several issues, the most dire being hepatitis or neoplasia (tumor).

Image G

Forensics: It’s Outlander Time. Yay! Ever wonder where Dougal met his Demise-by-Dirk (Starz, episode 213, Dragonfly in Amber)? No, not in the attic! I mean,  where was he stabbed? Did you think Claire and Jamie got him in the heart? Or, mayhap a lung? Forensic caps on!

Most likely, Dougal was stabbed in the liver! Yep. If ye look carefully, his wound is to the right of midline and above the costal margin. This means the dirk likely entered his RUQ, penetrating the right dome of respiratory diaphragm and piercing the right side of liver (Starz, episode 213, Dragonfly in Amber). No, Rupert, Jamie didn’t do the deed; or rather he didn’t do it alone!  It took four hands to finish Dougal off by Dirk-Deed! Dougal, man, we miss your sass!

As the heart lies mostly to the left of midline and right lower lung is to the right of the wound, neither of these organs were likely pierced. Good job, anatomy sleuths!

Physical Attributes: The adult liver is wedge-shaped, dense, and meaty, weighing 3-3.5 lb. Liver is our largest internal organ and the largest gland of the body, superseded in size only by our body’s largest organ, the skin (Anatomy Lesson #5, Claire’s Skin – Opals, Ivory and White Velvet). Ken the difference? Bonny!

Liver is solid in texture and deep red-purple-brown in color (Image H). Although liver mass constitutes only 2.5% of total body weight, the liver receives a whopping 25% of the cardiac output. Two and one-half pints of blood flow through a normal liver every minute of our lives!

Image H

Impressions: Front, back, and top surfaces of liver are relatively smooth; flip liver up-side-down, and its under-belly bears ridges and valleys. The depressions, named impressions, are created by contact with adjacent organs including stomach (gastric), duodenum, adrenal (suprarenal) gland, kidney (renal), and colon (Image I). Gallbladder also leaves an impression, but this is visible only after its removal. Ergo, liver is centrally-located in the upper abdominal cavity with many important organ contacts.

Image I

Anatomical Liver Lobes: Anatomists used landmarks to divide the liver into four anatomical lobes: right, left, caudate and quadrate (Image J). The large, right lobe (tan) is separated from the smaller left (yellow) by one of the membranes mentioned above, the falciform ligament. Only by viewing the undersurface are caudate (blue) and quadrate (green) lobes visible; caudate is nearer the spine and quadrate lies adjacent to gallbladder.

Image J

Blood Supply: Most organs receive blood via an artery and are drained by a vein. Not the liver! It is unique because it is the only organ receiving blood from both an artery and a vein; the hepatic vein delivers nutrient-rich blood derived from food digested in the gut, and the hepatic artery supplies oxygen-rich blood via the aorta. Three hepatic veins drain the liver (Image K).

Most organs are variations of a scarlet color because they receive oxygenated blood. Liver is a red-purple color because 75% of its blood supply is deoxygenated, nutrient-rich blood from the hepatic vein.

A dear long-time friend had a bit of trouble last year. Tests revealed that she had lost the blood supply to a segment of her liver with subsequent death of said segment! Cause unknown. She has given me permission to share this experience because it is unusual given she lacks any history of typical liver disorders or diseases. This is a wonderful example, though, of how dependent the liver is upon an intact blood supply!

Image K

Clinical Liver Segments: The next image looks scary, but bear with me here! Clinicians divide the liver into eight separate segments, numbered 1-8 or I-VIII (Image L); segment I (1) lies deep to IVa (4a) and IVb (4b), so it is not visible. Segments II and III lie to the left of the falciform ligament; all other segments lie to the right. Segmental divisions are determined by vascular supply and bile duct branching (see below) and are of great clinical import!

Image L

Clinical Liver Segments (cont.): Let’s say a cancer is found in liver segment IVb (4b). A competent surgeon determines the probable boundaries of IVb and resects only that segment, sparing remaining liver segments and minimizing blood loss. The surgeon performing these highly specialized surgeries must be thoroughly familiar with the segmental design as defined in Couinaud’s system (Image M).

Medical students have difficulty memorizing liver segments, but this fist mnemonic offers a useful visual. Note that the thumbnail (seen in ghost) represents the deep-lying, segment I.

Image M

Outlandish Lobes: Speaking of liver lobes… like you, I was deeply impressed by Master Raymond’s ministrations to Claire (and her liver) after her loss of Faith-faith (Starz episode 207, Faith). Her liver and other organs were infected; she probably had puerperal fever, a post-partum infection of the uterus that, if untreated, usually becomes systemic. Serious-Sobbing here (Dragonfly in Amber book)!

An odd feeling of warmth now emanated from those broad, square, workman’s hands. They moved with painstaking slowness over my body, and I could feel the tiny deaths of the bacteria that inhabited my blood, small explosions as each scintilla of infection disappeared. I could feel each interior organ, complete and three-dimensional, and see it as well, as though it sat on a table before me. There the hollow-walled stomach, here the lobed solidness of my liver, and each convolution and twist of intestine, turned in and on and around itself, neatly packed in the shining web of its mesentery membrane.

Bile Ducts and Gallbladder: Liver enjoys a robust working relationship with gallbladder and bile ducts. Why? Because, liver cells continuously produce bile, a dark green to yellowish-brown fluid. Bile is transported by a converging system of bile ducts from liver to gallbladder, a bag-like structure which stores and concentrates bile (Image N). Bile is then released in a controlled fashion after chyme (Anatomy Lesson #46, Splendid Stomach, Wobbly Wame) enters the duodenum. In folks lacking a gallbladder, bile ducts continuously release bile into the duodenum.

Bile: Two important purposes are served by bile:

  • Digestive aid: After eating a meal (especially high in fat), bile is released from gallbladder into duodenum (Anatomy Lesson #47, Brave Bowels – Gurgly Gut!) where it aids in lipid digestion by fats emulsification.
  • Excretory product: Specialized liver (Kupffer) cells devour effete red blood cells, breaking down hemoglobin into bilirubin, a waste component of bile that is eliminated with the stool.

Bile enjoys a long history in western medicine. From 500 B.C. to the early 19th century, standard practice adhered to a four humor system: black bile, yellow bile (liver bile), phlegm, and blood. Excesses of black and yellow biles were thought to produce depression and aggression and were treated accordingly (sometimes with phlebotomy). If only physiology/psychology were that simple!

Image N

Hepatocytes: The hepatocyte is the main functioning cell of the liver (there are other cell types, too). It’s prefix derives from the Greek word, hepar, meaning liver. Microscopically, the hepatocyte (image O – arrows point to hepatocyte cell membranes) is a large, round, bland-looking cell, but what a power-house it is!

Hepatocytes are arranged into 1-2.5mm cylinders, each known as a liver lobule. I will not teach liver lobule structure here as it is complex and difficult to understand for students lacking histology training – beyond the scope of this anatomy lesson. Suffice it to say that the liver is packed with millions of these tiny liver lobules. Their designs allows hepatocytes to have immediate access to blood vessels and bile channels. This allows ready access to substances in the blood stream and to release bile into bile channels for transport to the gallbladder.

Image O

Image P is a nice graphic summarizing a few liver functions – most are self-explanatory. Hepatocytes are responsible for almost all the ∼500 liver functions. Just a note about the Kupffer cell (Image O – arrowhead). a phagocyte, meaning “eating cell.” Kupffer cells ingest effete red blood cells (and other things), turning hemoglobin into bilirubin, a component of bile. Just consider: maintaining such a huge organ would be wasteful if it weren’t highly important – it wears many hats!

Image P

Liver Diseases: Liver is subject to a staggering array of diseases – from genetic disorders, autoimmunities, viral hepatitis, and parasitic liver flukes to cancer, chronic alcohol disease, poisoning, drug abuse, excessive use of over-the-counter pain relievers, etc. Although liver has a tremendous capacity to regenerate, long-term damage may result in the formation of scar tissue. A scarred liver is characteristically bumpy, a condition known as cirrhosis (Image Q). In the 18th century, Claire would have said the patient with a cirrhotic liver was liver-sick and cirrhotic livers were termed hobnailed livers. Just so you ken, hobnails are a short, heavy-headed nails used to reinforce the soles of boots. Bless Diana’s heart, she even wrote about cirrhotic livers (Dragonfly in Amber book)!

I knelt by the small traveling chest, unfolding the green velvet. Kneeling next to me, Jamie flipped back the lid of my medicine box, studying the layers of bottles and boxes and bits of gauze-wrapped herbs. “Have ye got anything in here for a verra vicious headache, Sassenach?” I peered over his shoulder, then reached in and touched one bottle. “Horehound might help, though it’s not the best. And willow-bark tea with sow fennel works fairly well, but it takes some time to brew. Tell you what—why don’t I make you up a recipe for hobnailed liver? Wonderful hangover cure.”

Liver dialysis can be used as a stop-gap treatment, but liver transplant is the only current option for complete liver failure. If all goes well, the transplant regenerates much of the original liver mass.

Image Q

Leaving that unhappy liver-note, let’s end on a happier liver quote!

Recall Starz, episode 105, Rent? One of my favs.

Intruder alert! With a massive candle stick, Claire goes after someone fussing outside her door!

Dashing outside, she encounters Jamie, sprawled on the filthy floor. “What are you doing here?” she demands (Outlander book), after stepping on his RUQ. Watch out lovely, lively liver! Crunch!

“What are you doing here?” I asked accusingly. At the same time Jamie asked, in a similarly accusatory tone, “How much do ye weigh, Sassenach?” Still a bit addled, I actually replied “Nine stone,” before thinking to ask “Why?” “Ye nearly crushed my liver,” he answered, gingerly prodding the affected area. “Not to mention scaring living hell out of me.”

Nurse Claire, in the hallway with a candlestick? <G> She almost brains Master Fraser! And her weight? What gently-bred Scottish lad asks a lass how much she weighs? Geez, at 126 lbs, Claire is a just wee thing!

And, Jamie, you drink Scotch whiskey so we all ken your liver can take a trashing! Uh oh, we’ve seen that look before. Run, Claire, run! Hah!

So, the liver may look boring, but is a bundle of life: 500 duties it performs to keep our bodies healthy and happy. We literally live in our liver!

Let’s end this lively liver lesson with a great quote from American physician and psychologist, William James:

Is Life worth living? It all depends on the liver.

And, from my own pen:

Liver the giver

makes us shiver and quiver

bound to deliver

It’s a major caregiver!

So, Love your Liver!

A deeply grateful,

Outlander Anatomist

Photo Creds: Starz, www.techmeanatomy.info (Image J), www.arthistorynewsreport.blogspot.com (Image C), www.cojs.org (Image B), www.commons.wikimedia.org (Image H), www.diets-usa.com (Image A), www.epomedicine.com (Image M), www.kenhub.com (Image F), www.medhealthdaily.com (Image G), www.medvizor.com (Image P), www.nature.com (Image L), www.ncbi.nlm.nih.gov (Image N), www.pathpedia.com (Image O), www.pinterest.com (Image I), www.skylerzarndt.com (Image E), www.vaxy.com (Image Q), www.wikipedia.org (Image D), www.24nurse.com (Image K)