KEY NOTES CHAPTER 4: BREAST AND CHEST WALL - Breast Anatomy, Breast Reduction, Mastopexy, Augmentation. Flashcards
What is the arterial supply to the breast?
- Internal mammary artery perforators
- Pectoral branches of thoracoacromial axis
- Lateral thoracic artery
- Lateral branches of 3rd-5th intercostal arteries.
(very similar to blood supply of pec major).
Tell me about the anatomy of the breast.
Breast base:
∘ Vertically: 2nd-6th rib.
∘ Horizontally: lateral margin of sternum to anterior axillary fold.
∘ Axillary tail of Spence extends superolaterally towards axilla.
Breast - lobes (15-20) - lobules - alveoli (10-100).
Duct system joins and opens into lactiferous ducts on the nipple.
Lobes are separated by fibrous septa from skin to pectoral fascia.
• Suspensory ligaments of Astley Cooper = upper breast.
• Septum of Würinger = thin horizontal fibrous septae from pectoral fascia along fifth rib, curves upwards into vertically oriented medial and lateral ligaments.
∘ Attaches breast to sternum and lateral edge of pectoralis minor.
∘ Carries main nerve supply to the nipple with intercostal perforators.
What is the nerve supply of the breast?
- Anterior cutaneous branches of 2nd-6th intercostal nerves.
- Anterior cutaneous branches of 3rd-6th lateral cutaneous nerves.
- Supraclavicular branches of cervical plexus.
- Main supply to nipple = branches of 4th lateral cutaneous nerve.
Who described the ideal breast measurements and what are they?
Penn described ‘ideal’ breast measurements:
∘ Sternal notch - nipple distance = distance between nipples ~ 21cm (equilateral triangle).
∘ Nipple to IMF ~ 6.8 cm.
∘ Areolar diameter ~ 3.8 to 4.5 cm.
How are bra sizes measured?
Band size
• Chest circumference (UK):
∘ At IMF (inches) + 4 or 5 inches (to make even number).
∘ Typically ~ 28 to 46 inches.
Cup size • Based on difference between band size and chest circumference around most prominent part of breasts: ∘ <1 inch difference - AA cup ∘ 1 inch difference - A cup ∘ 2 inch difference - B cup ∘ 3 inch difference - C cup ∘ 4 inch difference - D cup ∘ 5 inch difference - DD cup.
Summarise the history of breast reduction.
• Thorek (1920s): free nipple graft technique.
• Wise (1950s): keyhole pattern of skin incision.
• Strombeck (1960): horizontal bipedicle technique.
• Skoog (1963): modified Strombeck; superomedial pedicle technique.
• McKissock (1972): vertical bipedicle technique.
• Weiner (1973): superior pedicle technique.
• Ribeiro (1975): inferior pedicle technique.
• Lejour popularised vertical scar technique originally described by Lassus.
• Benelli (1990): round-block technique.
• Hall-Findlay (1999): modified vertical scar technique with a medial pedicle.
• Hammond (1999): short scar periareolar inferior pedicle reduction (SPAIR) technique.
• Hamdi (2005): uses septum of Würinger to maintain vascularity and sensation to
NAC.
Describe the breast reduction techniques.
Broadly classified by:
∘ Pattern of skin excision
∘ Design of NAC pedicle.
What different patterns of skin excision do you know of?
• Wise pattern, aka ‘keyhole’ /
‘inverted T’.
• Regnault: ‘B’-shaped skin excision.
• Lejour: popularised vertical skin excision.
• Marchac: vertical excision. with short lateral extensions.
• Benelli: periareolar.
What is the pedicle composed of?
• Blood reaches the NAC via a pedicle from the chest wall, composed of:
∘ Glandular tissue, or
∘ Glandular tissue and de-epithelialised dermis, or
∘ Horizontal septum of Würinger.
What is the free nipple graft technique?
• NAC is removed and replaced as a graft.
• Advantages:
∘ Avoids morbidity associated with a long pedicle.
∘ Relatively quick and easy to perform.
• Disadvantages:
∘ Poor ‘take’ of the NAC.
∘ Loss of nipple sensation and pigmentation.
• Generally reserved for older patients requiring large reductions.
Describe the inferior pedicle technique.
• Advantages:
∘ Relatively simple to learn.
∘ May preserve nipple sensation via the 4th lateral cutaneous nerve.
• Key points:
1 The pedicle must remain attached to the chest wall (avoid undermining).
2 Base of the pedicle can be inclined laterally (increases chance of including a sensory branch in pedicle).
3 In firm breasts, the width of the keyhole pattern should be narrowed (otherwise undue tension may be placed on skin flaps).
4 The NAC should never be sited too high (difficult to correct). Nipples should lie just below most prominent part of breast.
Describe the medial (superomedial) pedicle technique.
• With the patient upright it looks like more of a superomedial pedicle.
• The Hall-Findlay technique combines it with vertical skin excision.
• Key technical points:
1 Create a full thickness dermoglandular pedicle down to chest wall, without exposing
pectoralis fascia.
2 Parenchymal resection predominantly inferiorly and laterally.
3 The inferior border of the pedicle becomes the medial breast pillar after the nipple is
rotated into position.
4 Pillars are sutured together to cone the breast; skin redrapes over the parenchyma.
Define mastopexy. How is it classified?
Ptosis is corrected by elevating breast tissue and NAC by excision of breast skin without parenchymal resection.
Regnault classification:
1st degree: Nipple lies at level of IMF, above the lower contour of the gland and skin brassiere.
2nd degree: Nipple lies below IMF but above lower contour of breast.
3rd degree: Nipple lies below IMF and at lower contour of breast.
Pseudoptosis: Major portion of breast mound lies below IMF while NAC remains at level of IMF (after breast reduction).
How can breast ptosis be surgically corrected?
Augmentation only
Skin excision and glandular remodelling
- Periareolar technique
- Vertical scar
- Inverted T scar
- L-shaped scar
What are the advantages and disadvantages of augmentation only to correct breast ptosis?
• Implants can increase breast volume and improve contour with minor ptosis.
• Not suitable for more severe ptosis because:
1. An excessively large implant would be required to tighten slack skin (and heavy implants accelerates recurrence of ptosis in poor quality stretched skin).
2. Ptotic skin may hang over implant creating a ‘double-bubble’ or ‘Snoopy-nose’
appearance.