Week 6 - Anatomy Tutorial - Breasts (supply,drainage, lumps), Menstrual Hormones, Uteurs/ovary/fallopian tubes location,arterial supply)

Question 1

The female breast is for nutrition of the newborn and is a modified sweat gland. * How many lobes does each breast have? Each lobe is comprised of many lobules at the end of which is a gland which produces milk * Which hormone stimulates milk production?

Answer 1

Each breast has 15-25 lobes , each lobe consists of many lobules with glands at the end which produce milk Prolactin is the hormone which stimulates the production of milk from the glands

Question 2

The 15-20 lobes of the breast are embedded in fat. When the breast milk is produced in the alveoli of the glands (the end of each lobule), each lobule drains milk into terminal ducts which branch together to form which duct?

Answer 2

The terminal ducts draining milk from each lobule in the lobe drain into the lactiferous ducts

Question 3

The lactiferous ducts drain milk from the breast lobes to the nipples. What is the dilated protion of the lactiferous duct which is under the areola, where the milk is drained via? (can be stored here)

Answer 3

The lactiferous ducts, via the AMPULLA under the areola, drain to the nipple

Ampullae means - . a dilated portion of a canal or duct

Question 4

Do not forget that although the breast is considered essentially female, men do have rudimentary breast tissue, which may enlarge if levels of female sex hormones are abnormally raised and may even develop carcinoma. During pregnancy the lobes of the breast enlarge (like a bunch of grapes) - what causes this enlargement?

Answer 4

The enlargement is due to increasing hormones during pregnancy, oestrogen and progesterone and at delivery these hormone levels dramatically drop (as the placenta is no longer in the body) causing a spike in prolactin levels

Question 5

Where does the bed of the breast extend from?

Answer 5

The bed of breast extends from ribs 2 to 6 on the lateral border of the sternum to the midaxillary line

Question 6

The bed of the breast lies from ribs 2to6 on the lateral sternal border to the mid axillary line on deep fascia overlying which muscles?

Answer 6

Deep fascia which overlies the pectoral major, the serratus anterior and the upper edge of the external oblique muscles

Question 7

What are the attachement points of the pec major muscle? (remember pec major two origins) WHat is the nerve supply?

Answer 7

Pectroalis major -

• Origin -
  
  • * Medial 1/3rd of the clavilce and
  • * Sternum and costal cartilages of ribs 1-6
• Insertion
  
  • * Bicipital groove of humerus (intertubercular groove)
• Nerve supply - Medial pectoral and lateral pectoral nerve

Question 8

What are the attachement points of the serratus anterior muscle? WHat is the nerve supply?

Answer 8

Serratus anterior Origiin Ribs 1to 8 Insetion - medial border of the scapula Nerve supply - long thoracic nerve (C5,6,7)

Question 9

What is the extension of the breast tissue that heads towards the axilla known as? (comes from the upper outer quadrant of each breast) This extension pierces the deep pectoralis fascia through what foramen to reach the axilla?

Answer 9

This is the Axillary Tail of Spence It curves under the pec major and pierces the deep pectoralis fascia to travel to the axilla - the piercing in the deep pectoralis fascia is known as the foramen of langer

Question 10

What is the space that lies between the deep fascia and the breast? What does this space allow for?

Answer 10

This would be the retromammary space It allows for for some movement in relation to the underlying muscle

Question 11

When the tumour invades the retromammary space, what may this cause to the mobility of the breast? What are the ligaments that attach the breast to the deep fascia? - they are important for supporting the breast

Answer 11

When an advanced tumour invades the retromammary space, it may anchor the breast - this is a sign of breast cancer

The suspensory ligaments of cooper attach the breast to the deep fascia and are important for supporting the breast

Question 12

As said, the breast is mobile on the wall of the chest due to the retromammary space If there is a lump in the breast, you can check to see if it is fixed or not to the pectoral facia (if it is fixed there is a worse prognosis) How is this done?

Answer 12

The patient is asked to put their hands on their hips firmly to contract the pecs - if the lump is then not mobile - it makes one think that it may have invade the fascia and is attaching to muscle - more likely to be cancerous

Question 13

The position of the nippled and areola are variable but what level are they usually at in a young female? What happens to the colour of the nipple and areaola after pregnancy?

Answer 13

The position of both are variable but they usually lie at the level of the fourth intercostal space in a young female The colour of the nipple and areola are usually light in a nullparous female and darken after pregnancy

Question 14

The areola aslo contains many sebaceous glands, what may there function be?

Answer 14

The areola has many sebaceous glands that have a lubricating, protective function during suckling.

Question 15

The blood supply to the breast: is important, but it also gives a guide to the lymph drainage. What are the two main arteries which supply blood to the breast?

Answer 15

The two main arteries are the internal thoracic and the axillary artery Internal thoracic artery is a branch of the subclavian artery and supplies the medial breast The axillary artery is a continuation of the subclacian artery and supplies the lateral breast

Question 16

The two main sources to the breast are via axillary artery (lateral thoracic and acromiothoracic branches) and from internal thoracic artery (via the perforating branches). Which two main anterior intercostal branches of the internal thoracic artery supply the breast?

Answer 16

This would be mainly the 3rd and 4th anterior intercostal artery branches

Question 17

Where does the majority of lymph from the breast drain to? Where is the next common place for lymph drainage from the breast?

Answer 17

The majority of lymph drainage form the breast goes to the axillary lymph nodes - 75% Most of the other 25% goes to the parasternal nodes

Question 18

Whatever the site of a breast cancer, any spread is likely to be to the axillary nodes and the operating surgeon will sample the axillary nodes for possible spread. Why is it that removing the axillary lymph nodes in the treatment of some cancers eg breast cancers can have implications?

Answer 18

Lymph from the upper limbs also drains to the axillary nodes, therefore this can result in lymphoedema

This condition of localized fluid retention and tissue swelling is caused by a compromised lymphatic system, which normally returns interstitial fluid to the bloodstream.

Question 19

From an anatomical point of view the axillary lymph nodes are arranged as follows in a certain way What is the Acronym to put these 6 groups of axillary nodes in order? They orientate around the pectoralis minor muscle mainy

Answer 19

• * A - Anterior (pecotral group) - just below lateral (lower) edge of pec minor draining breast and anterior body wall above umilicus
• * P - Posterior (subscapular) on subcapularis - drains posterior body wall above umbilucs
• * I - Infraclavicular - not sure what this drains
• * C - Central - these lie behind the pec minor
• * A - Apical - lie medial to the medial (upper) border of pec minor
• * L - Lateral (humeral)-around axillary vein-drains upper limb

Question 20

Which axillary lymph node drains the breast and anterior body wall above the umbilicus? Which axillary lymph node drains lymph from the upper limb? Which axillary lymph node drains lymph ffrom the posterior body wall above the umbilucs? State where each group that drains these lies

Answer 20

* The anterior (pectoral) groups of lymph nodes - just below the lateral lower edge of the pec minor - drains the breast and the anterior body wall above the umbilicus * The lateral axillary lymph nodes- around the axillary vein - drains the upper limb * The posterior (subscapular) - on the subscapularis - drains the posterior body wall above the umbilicus

Question 21

Talked about the anterior (pectoral) lymph nodes - just below the lateral (lower) edge the pec minor The lateral axillary lymph nodes - around the axillary vein The posterior (subscapular) lymph nodes - on the subscapularis What are the other three and where are they located?

Answer 21

The Infraclavicular- below the clavicle Central - lying behind the pectoralis minor Apical - medial to the medial (upper) border of the pec minor

Question 22

Where do the anterior group (draining the breast) posterior (draining posterior body wall) and lateral (draining the upper limb) all drain to?

Answer 22

These all drain to the central axillary lymph nodes - located behind the pectoralis minor

Question 23

The central axilllary lymph nodes drain with which other group of axillary lymph nodes to where?

Answer 23

The central axillary lymph nodes along with the infraclavicular lymph nodes drain to the apical lymph nodes. Afferents from the latter communicate with the deep cervical nodes and drain to the subclavian lymph trunk.

Question 24

What are the attachments and nerve supply of the pectoralis minor muscle?

Answer 24

Attachments - Origin - ribs 3,4,5 Insertion - coracoid process of the scapula Nerve supply - the medial pectoral nerve

Question 25

The axillary node individual groups are usually indistinguishable in a normal cadaveric dissection. But they are significant in staging the spread of breast tumours. What are the surgical levels for the spread of breast tumour to the axillary nodes and what is their relevance? Levels 1,2,3 - basically how the breast drains

Answer 25

* Level 1 lymph node - spread to anterior group - this is just below the lateral edge of pec minor * Level 2 - spread to central group deep to the pectoralis minor * Level 3 - spread to the apical group - medial to the medial (upper) border of pectoralis minor These are important for axillary clearance of breast cancer Level 1 is viewed as the sentinel node (anterior group) and if this is clear, radical clearance is not required

Question 26

Apical node involvement is a very significant and worrying feature in breast cancer. The communication between axillary and deep cervical lymph nodes means that breast tumours may spread to the latter, and it is also possible for tumour to disrupt the expected route of lymph drainage and promote spread across the midline, into the abdomen, into the vertebrae, up to the cervical nodes or down to inguinal nodes. What nerve may be injured during axillary clearance?

Answer 26

The long thoracic nerve may be injured during axillary node clearance

Question 27

During pregnancy, a variety of breast changes occur. Typically, breasts become tender and the nipples become sore a few weeks after conception. The breasts also increase in size. When is the increase in breast size most rapid?

Answer 27

The increase in breast size is most rapid in the first 8 weeks of gestation

Question 28

The Montgomery‟s gland surrounding the areola becomes darker and more prominent, and the areola itself darkens. The nipples also become larger and more erect as they prepare for milk production. Which hormone promotes the blood vessels within the breast to enlarge as its levels surge during pregnancy?

Answer 28

Oestrogen surges promotes blood vessels within the breast to enlarge

Question 29

Oestrogen and progesterone both promote breast enlargement during pregnancy What effects do both have on the breast tissue?

Answer 29

Oestrogen surges promote the blood vessels in the breast to enlarge and the growth of the ducts Progesterone surges promote the glandular tissue to expand

Question 30

Two hormones are responsible for milk production: prolactin and oxytocin. During pregnancy, high circulating concentrations of estrogen and progesterone increase prolactin levels by 10- to 20-fold. Estrogen and progesterone block some of the prolactin receptors and inhibit milk production. The abrupt drop of estrogen and progesterone levels following delivery causes prolactin levels to decline What is the substance produced by the breasts before breast milk comes in?

Answer 30

This is colostrum - rich in antibodies to help protect the infant against infections (IgA rich) The breast milk comes in around 3-5 days after birth

Question 31

When an infant suckles at the mother‟s breast, it brings milk out of the nipples. This suction signals the body to make more milk (using prolactin) and deliver more milk (using oxytocin). how does oxytocin caue the delivery of milk?

Answer 31

It causes the contraction of smooth muscle leading to milk ejection

Question 32

When a women reaches menopause, what causes a reduction in the size of the breasts?

Answer 32

The reduced levels of oestrogen and progesterone

Question 33

The breast glandular tissue, which has been kept firm so that the glands could produce milk, shrinks after menopause and is replaced with fatty tissue. The breasts also tend to increase in size and sag because the fibrous (connective) tissue loses its strength. Because the breasts become less dense after menopause, it is often easier to detect breast cancer on an older woman’s mammogram films, since abnormalities are not hidden by breast density. WHen should mammogram screening therefore commence in women?

Answer 33

Mammogram screening should commence at age 50 for all woman for breast cancer - it is easier to detect breast cancer on an older woman as the breasts are less dense Womens risk of breast cancer increases with age

Question 34

What is the pituitary gland also known as? What is its anterior and posterior also known as?

Answer 34

Pituitary gland is also known as the hypophyisis antieor pituitary - adenohypophysis Posterior pituitary - neurohypophysis

Question 35

The pituitary gland, also known as the hypophysis, has a posterior neurohypophysis and an anterior adenohypophysis. Where does the pituitary gland lie? WHat is the flat piece of dura that lies over the pituitary gland with a circular hole to allow for passage of the pituitary stalk?

Answer 35

The pituitary gland sits in the pituitary fossa which lies in the depression in the sphenoid bone known as the sella turcica The pituitary glads is covered by a flat piece of dura mater known as the diaphragma sella

Question 36

What is the pituitary stalk also known as and what does it connect to? What sinus lies immediately inferior to the pituitary gland?

Answer 36

The pituitary stalk is also known as the infundibulum - connects the pituitary gland to the hypothalamus The sphenoid sinus lies immediately inferior to the gland

Question 37

On each side of the sphenoidal air sinus and pituitary gland are the left and right cavernous venous sinuses What do each of these sinuses contain in each lateral wall?

Answer 37

On each side lie the right and left cavernous sinus Contents in lateral wall: Internal carotid artery Oculomotor nerve (CN III) Trochlear nerve (CN IV) Ophthalmic division of trigeminal nerve (CN V1) Maxillary division of trigeminal nerve (CN V2) Abducent nerve (CN VI)

Question 38

What does the neurohypophysis secrete?

Answer 38

Neurohypophysis secretes: * Oxytocin - controls muscle contraction in the mmary gland and in the uterus * ADH - controls water reaborption in the kidney

Question 39

What is the function of the anterior pituitary gland?

Answer 39

The anterior pituitary gland releases hormones stored in a portal circulation from the hypothalamus: TSH ACTH LH - reproductive hormone FSH - reproductive hormone Prolactin

Question 40

What effect does prolactin have on the LH and FSH levels?

Answer 40

Prolactin jinhibits the levels of GnRH which is a hormone in the hypothalamus which stimulates the production of LH and FSh - therefore high prolactin levels prevent the production of these

Question 41

What does LH and FSH act on in the female to stimulate?

Answer 41

FSH - acts on the ovary to stimulate follicular development and stimulate the granulosa cells in the ovarian follicle to secrete oestrogen LH - acts on the follicle to stimulate ovulation and also stimulates the granulosa cells in the ovarian follicle to secrete oestrogen LH also stimulates the corpus luteum to produce progesterone in the luteal phase of the cycle

Question 42

State what LH acts on again in the female? What day can which hormone be measured to check if ovulation has happened?

Answer 42

LH acts on the ovary to stimulate the granulosa cells in the ovarian follicle to produce oestreogen. It also acts on the follicle to induce ovulation. LH also acts on the corpus luteum to produce progesterone Measure progesterone levels at day 21 of menstrual cycle - checks if ovulation has occured If it had not, then corpus luteum would not form and therefore no progesterone spike

Question 43

What does LH and FSH act on in males?

Answer 43

LH - acts on LEydig cells to produce testosterone FSH - acts on Sertoli cells to stimulate spermatogenesis

Question 44

What hormonal imbalances could result from a pituitary tumour?

Answer 44

headache related to intracranial pressure effect of pituitary tumour bitemporal hemianopia: due to compression of optic chiasma galactorrhoea (breast milk secretion) due to elevated prolactin levels (rarely other hormone can be secreted eg growth hormone or ACTH) - pituitary failure, due to compression of pituitary gland (causing low cortisol levels, low thyroxine, low LH and FSH)

Question 45

Sperm entering the vagina pass through the cavity of the uterus and into the uterine tube, where fertilisation of the ovum occurs in the ampullary region. The fertilised ovum is then transported down the tube by ciliary action to implant and develop within the endometrium. Should such transport not occur the fertilised ovum might develop in the tube as an ectopic, tubal pregnancy What does a normal hysterosalpingogram show?

Answer 45

A HSG is an x-ray examination of a woman’s uterus and fallopian tubes that uses a special form of x-ray called fluoroscopy and a contrast material. Normally this shows the fallopian tubes filling with the radio-opaque dye and the dye then spills out of the fallopian tubes into the peritoneal cavity - this shows that the fallopian tubes are patent

Question 46

In the nulliparous, young female the ovary lies in a fossa on the lateral pelvic wall and is about the size of an almond. In the elderly female the ovary is usually shrunken. What ligament do the fallopian tubes lie within? What are the other names for the fallopian tubes?

Answer 46

The fallopian tubes, aka the uterine tubes or the oviducts lie in the upper, free edge of the broad ligament

Question 47

What is each region of the fallopian tube, from uterus to ovary?

Answer 47

Uterus to ovary

The isthmus, then ampulla, then infundibulum

At the end of the fallopian tube are the fimbrea which overhang the ovary inside the peritoneal cavity and sweep ovulated eggs into the oviduct

Question 48

At what angle should a vaginal speculum be inserted in order to view the cervix?

Answer 48

It should be inserted at a 45 degree angle towards to the coccyx and rotated to the 12 oclock position

Question 49

What is the portion of the broad ligament that the ovaries are suspended within known as? What is the portion of broad ligament that acts as a mesentery for the uteirne tube known as?

Answer 49

This portion is known as the mesovarium The part of the broad ligament that acts as a mesentery for the tube is called the mesosalpinx.

Question 50

At ovulation the ovum is secreted into the peritoneal cavity, to be “picked up” by the uterine tube. This is by the fimbriae WHat is the blood supply to the ovaries? What level do these arteries arise? Where does the venous drainage go to? Where does the ovarian lymph drainage go to?

Answer 50

Ovaries supplied by the ovarian artery which arises at the L2 level on the abdominal aorta The right ovarian vein drains to the inferior vena cava The left ovarian vein drains to the left renal vein Goes to the para-aortic lymph nodes

Question 51

What is the venous drainage of the uterus and where does it go to?

Answer 51

Drain via the uterine veins to the external iliac vein

Question 52

Pain from the ovaries (and fallopian tubes and uterus) travels via visceral afferents Where is pain from superior part of pelvic organs perceived as? Where is pain from inferior part of pelvic organs perceived as? (ie cervix)

Answer 52

Pain from superior - suprapubic Pain from inferior - perineum

Question 53

The pelvic organs both use visceral afferents to relay sensation to the spinal cord however Superior aspect of pelvic organs / touching the peritoneum - Run alongside sympathetic fibres Inferior aspect of pelvic organs / not touching peritoneum - Run alongside parasympathetic fibres What are the different spinal cord roots for these exact fibres?

Answer 53

For superior part of pelvic organs - run alongside sympathetic fibres to enter spinal cord at levels T11-L2 For inferior part of pelvic organs - run alongside parasympathetic fibres to enter the spinal cord at S2,3,4

Question 54

Ovarian sympathetic innervation, with its accompanying afferents, is derived from the lesser splanchnic nerves, T10-11. Therefore, ovarian (visceral) pain may refer to the T10-11 dermatomes, in the midline, the peri-umbilical region (as well as to the medial thigh via the obturator nerve). Uterine nerve supply is via the pelvic plexus containing both sympathetic (T10-12 and L1-L2 levels) and parasympathetic (S2,3,4 levels) components. Which parts of the uterus are thought to be sympathetic or parasympathetic?

Answer 54

Afferents from the body and fundus are thought to pass with the sympathetics so that pain is lower abdominal. But those of the cervix are thought to pass with the parasympathetics giving deep pelvic pain.

Question 55

Describe the blood supply to the uterus. What anastomosis occurs in this area and what are the origins of the arteries contributing to the anastomosis?

Answer 55

The uterus is supplied by the uterine arteries, which are branches of the internal iliac. These anastomose freely with each other and with the ovarian arteries, which tend to supply the fundus. The uteirne artery gives of the vaginal artery which supplies the superior vagina and cervix And these arteries anastamose via the vaginal branch of the uterine arteery Uterine artery also anastamoses with ovarian artery via the ovarian and tubal branch of the uterine artery

Question 56

What does the vaginal artery anastamose with that supplies the lower 1/3rd of the vagina?

Answer 56

It has an anastamoses with the internal pudendal artery

Question 57

Lymph drainage of the fundus tends to follow the ovarian artery to the para-aortic nodes. Where does the body and cervix of the uterus lymph tend to drain?

Answer 57

Tends to drain to the sacral and external iliac lymph nodes

Question 58

Identify the features that can be seen in the ultrasound that are in keeping with the diagnosis of a ‘threatened’ miscarriage, rather than an actual miscarriage

Answer 58

USS shows a live intrauteriine gestation

• Likely the foetal heart can be visualised and heard
• Usually the cervical os is closed

Threatened miscarriage, is mainly a clinical term, used when a pregnant woman in first 20 weeks of gestation presents with spotting, mild abdominal pain and contractions, with a closed cervical os.