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.
Elaborate on the different skin excision and glandular remodelling techniques.
Periareolar technique
• A concentric ring of skin/tissue is de-epithelialised around NAC.
• Breast skin is tightened by suturing outer ring to NAC.
• Benelli described ‘round-block’ technique of securing NAC after circumareolar mastopexy:
1 A purse-string (‘round-block’) reduction of outer dermal circumference with a permanent suture.
2 A ‘skin compensation suture’: horizontal bites of outer dermal circumference, but vertical bites of NAC.
• Advantages:
∘ Reduces stretching of NAC.
∘ Reduces nipple herniation through the ‘round-block’.
∘ Minimises puckering.
Vertical scar technique
• Adds a vertical or oblique limb to the periareolar skin excision:
∘ Allows more skin to be excised.
∘ Helps elevate the NAC.
Inverted T scar technique
• Wise pattern is used for severe ptosis (With inelastic skin):
∘ Removes large amounts of excess skin.
∘ Transposes NAC into its correct position.
L-shaped scar technique
• Eliminates medial and shortens lateral horizontal scar of Wise pattern.
• Best for correcting first or second degree ptosis.
What are the complications of mastopexy and breast reduction?
General
• GA, DVT, PE
• Chest infection, atelectasis
Early • Altered nipple sensation (20%) • Haematoma (1%) • NAC necrosis (<0.5%) • Infection.
Intermediate
• Wound healing problems (5%)
• Seroma
• Fat necrosis.
Late • Inability to breastfeed (up to 50%) • Hypertrophic or keloid scarring • Lumpiness • Under- or over-resection • Asymmetry • Dog ears.
How did breast augmentation evolve?
- 1890: paraffin wax injections.
- 1950: polyvinyl sponge implants.
- 1960s: silicone gel prosthetic augmentation (Cronin and Gerow).
~ 3% of women in the United States have undergone breast augmentation.
• In UK, >10,000 women had cosmetic breast implants in 2011.
How do you classify breast augmentation (implant) procedures?
Implant-based breast augmentation can be classified by:
∘ Composition and surface of implant shell (silicone, polyurethane, smooth, textured)
∘ Contents of implant (silicone (liquid or cohesive gel), saline, hydrogel, triglyceride = trilucent soybean oil (1995-99 now withdrawn), hyaluronic acid,
∘ Implant shape (round, anatomical)
∘ Site of incision: IMF, axillary, periareolar, umbilical, endoscopic)
∘ Site of implant placement: subglandular, subfascial, subpectoral, dual plane, submuscular, ADM.
What are the pros and cons of round vs anatomical implants?
• There is controversy about whether shaped or round implants produce a better result:
• Anatomical
∘ Designed to resemble natural breast contour and may produce more natural breast shape.
∘ Less upper pole and more lower pole projection (various projections, heights and widths available).
∘ Particularly suitable for thin patients at risk of excessive upper pole fullness.
∘ may rotate within their pocket.
Round
∘ become anatomically shaped when held upright to some extent.
∘ can create an obvious step in upper pole (more synthetic look esp. subglandular - which some patients like).
Describe the different planes of implant placement.
Subglandular pocket
• Deep to breast tissue but superficial to pectoralis fascia.
Subfascial pocket (Graf 1998).
• Pocket between pectoralis fascia above and pectoralis major below.
• May decrease visibility of implants and reduce risk of capsular contracture compared to subglandular placement.
Subpectoral pocket
• Deep to pectoralis major but superficial to pectoralis minor.
• Lower pole of the implant may lies inferior to edge of muscle.
Dual plane (Tebbetts) • Subglandular dissection extends above inferior border of pectoralis major for a variable distance towards superior border of NAC, then subpectoral pocket is created. • Allows both implant placement and soft tissue redraping, which can avoid a double-bubble deformity in certain patients with ptosis.
Submuscular pocket
• Most of pocket lies under pectoralis major. Laterally under serratus anterior. Inferiorly under rectus abdominis fascia.
• Initially advocated by S. Spear. who has since changed his practice with ADM,
which is used to ensure total implant coverage.
What are the uses of ADM in breast augmentation?
Pocket fashioned with ADM
• Primary and secondary augmentation uses:
∘ Within pocket to bolster areas of thin tissue.
∘ To minimise visible rippling.
∘ To support lower pole of implant and maintain IMF position.
• ? reduce capsular contracture.
What was the controversy with silicone implants?
• In the early 1980s, concerns arose over whether silicone implants were responsible for:
∘ Some types of autoimmune disease
∘ Increased risk of breast cancer
∘ Difficulties in screening for cancer.
∘ A class action lawsuit (200,000 women) against Dow Corning was settled in 1997 (USD 2.4bn).
- In 1992, US FDA removed all silicone gel-filled breast implants from market.
- Following years of investigation, FDA approved specific types of Allergan and Mentor® silicone gel-filled breast implants in 2006, on condition that each manufacturer conducts six studies to assess long-term performance and safety of their devices.
- ‘Core’ study followed women for 10 years and assessed effectiveness of MRI in detecting implant rupture.
- Allergan enrolled 715 women; Mentor 1008.
What were the findings of the Independent Review Group in the UK?
In 1998, report concluded silicone breast implants are not associated with greater health risk compared to other surgical implants.
• No evidence of association with:
∘ abnormal immune response.
∘ typical or atypical connective tissue diseases or syndromes.
∘ Increased risk of connective tissue disease in children of implanted women.
• Silicone implants are associated some local complications:
∘ Implant rupture
∘ Capsule formation.
• Report recommended a national implant registry to record details of all women undergoing breast augmentation.
