Mastopexy


Mastopexy is the plastic surgery mammoplasty procedure for raising sagging breasts upon the chest of the woman, by changing and modifying the size, contour, and elevation of the breasts. In a breast-lift surgery to re-establish an aesthetically proportionate bust for the woman, the critical corrective consideration is the tissue viability of the nipple-areola complex, to ensure the functional sensitivity of the breasts for lactation and breast-feeding.
The breast-lift correction of a sagging bust is a surgical operation that cuts and removes excess tissues, overstretched suspensory ligaments, excess skin from the skin-envelope, and transposes the nipple-areola complex higher upon the breast hemisphere. In surgical practice, mastopexy can be performed as a discrete breast-lift procedure, and as a subordinate surgery within a combined mastopexy–breast augmentation procedure.
Moreover, mastopexy surgery techniques also are applied to reduction mammoplasty, which is the correction of oversized breasts. Psychologically, a mastopexy procedure to correct breast ptosis is not indicated by medical cause or physical reason, but by the self-image of the woman; that is, the combination of physical, aesthetic, and mental health requirements of her self.

The patient

The usual mastopexy patient is the woman who desires the restoration of her bust, because of the post-partum volume losses of fat and milk-gland tissues, and the occurrence of breast ptosis. The clinical indications presented by the woman—the degrees of laxness of the suspensory Cooper's ligaments; and of the breast skin-envelope —determine the applicable restorative surgical approach for lifting the breasts. Grade I breast ptosis can be corrected solely with breast augmentation, surgical and non-surgical. Severe breast ptosis can be corrected with breast-lift techniques, such as the Anchor pattern, the Inverted-T incision, and the Lollipop pattern, which are performed with circumvertical and horizontal surgical incisions; which produce a periareolar scar, at the periphery of the nipple-areola complex, and a vertical scar, descending from the lower margin of the NAC to the horizontal scar in the infra-mammary fold, where the breast meets the chest; such surgical scars are the aesthetic disadvantages of mastopexy.

Breast ptosis

;Etiology
Gravity is the most common cause of breast ptosis, or sagging.
  • In a young woman with large breasts the sagging occurs because the volume and weight of the bust is disproportionate to body type, and because of the great elasticity of the thin, young skin envelope of each breast.
  • In middle-aged women, breast ptosis usually is caused by postpartum hormonal changes to the maternal body and because of the inelasticity of the skin envelope, which is overstretched by engorgement during lactation.
  • In post-menopausal women, in addition to gravity, breast ptosis atrophy is aggravated by the inelasticity of overstretched, aged skin.
;Pathophysiology and presentation
In the course of a woman's life, her breasts change in size and volume as the skin envelope becomes inelastic, and the Cooper's suspensory ligaments—which suspend the mammary gland high against the chest—become loose, and so cause the falling forward and the sagging of the breast and the nipple-areola complex. Moreover, additional to tissue prolapse, postpartum diminishment of the voluminous milk glands in the breast aggravates the looseness of the suspensory ligaments, and of the inelastic, overstretched skin envelope. Mastopexy corrects said degenerative physical changes, by elevating the parenchymal tissues, cutting and re-sizing the skin envelope, and transposing the nipple-areola complex higher upon the breast hemisphere. The degree of breast ptosis of each breast is determined by the position of the nipple-areola complex upon the breast hemisphere; ptosis of the breast is measured with the modified Regnault ptosis grade scale.
;The Regnault ptosis grade scale
  • Grade I: Mild ptosis — The nipple is located below the inframammary fold, but remains located above the lower pole of the breast.
  • Grade II: Moderate ptosis — The nipple is located below the IMF; yet some lower-pole breast tissue hangs lower than the nipple.
  • Grade III: Advanced ptosis — The nipple is located below the IMF, and is at the maximum projection of the breast from the chest.
  • Grade IV: Severe ptosis — The nipple is far below the inframammary fold, and there is no lower-pole breast tissue below the nipple.
Laurence Anthony Kirwan published an alternative classification system for ptosis of the primary or non augmented breast that is meant to be better suited than the Regnault scale for planning surgery.
;Additional mastopexy considerations
Pseudoptosis — The indication is the sagging of the skin of the lower half of the breast, featuring the nipple located either at or above the inframammary fold ; as such, pseudoptosis is a usual consequence of postpartum milk-gland atrophy. The nipple is located either at or above the IMF, while the lower half of the breast sags below the IMF. Pseudoptosis usually occurs when the woman ceases nursing, because the milk glands have atrophied, and so reduced the volume of the breast, thus the sagging of the breast-envelope skin.
Parenchymal maldistribution — The lower breast lacks fullness, the inframammary fold is very high under the breast hemisphere, and the nipple-areola complex is close to the IMF. Such indications of the maldistribution of parenchymal tissues indicate a developmental deformity.

Surgical anatomy of the breast

Composition

Surgically, the breast is a milk-producing apocrine gland overlaying the chest; and is attached at the nipple, and suspended with ligaments from the chest; and which is integral to the skin, the body integument of the woman. The dimensions and the weight of the breasts vary with the woman's age and her habitus. Hence, small-to-medium-sized breasts weigh approximately 500 gm or less, and large breasts weigh approximately 750–1,000 gm. Anatomically, the breast topography and the locale of the nipple-areola complex on the breast hemisphere are particular to each woman; thus, the statistically desirable measurements are a 21–23 cm sternal distance, and a 5–7 cm inferior-limb distance, from the nipple to the inframammary fold, where the breast joins the chest.

Blood supply and innervation

The arterial blood supply of the breast has medial and lateral vascular components; it is supplied with blood by the internal mammary artery, the lateral thoracic artery, and the 3rd, 4th, 5th, 6th, and 7th intercostal perforating arteries. Drainage of venous blood from the breast is by the superficial vein system under the dermis, and by the deep vein system parallel to the artery system. The primary lymph drainage system is the retromammary lymph plexus in the pectoral fascia. Sensation in the breast is established by the peripheral nervous system innervation of the anterior and lateral cutaneous branches of the 4th, 5th, and 6th intercostal nerves, and thoracic spinal nerve 4 innervates and supplies sensation to the nipple-areola complex.

Mechanical structures of the breast

In realizing the breast lift, the mastopexic correction takes anatomic and histologic account of the biomechanical, load-bearing properties of the three tissue types that compose and support the breast; among the properties of the soft tissues of the breast is near-incompressibility.
  1. Rib cage. The 2nd, 3rd, 4th, 5th, and 6th ribs of the thoracic cage are the structural supports for the mammary glands.
  2. Chest muscles. The breasts lie upon the pectoralis major muscle, the pectoralis minor muscle, and the intercostal muscles, and can extend to and cover a portion of the anterior serratus muscle, and to the rectus abdominis muscle. The body posture of the woman exerts physical stresses upon the pectoralis major muscles and the pectoralis minor muscles, which cause the weight of the breasts to induce static and dynamic shear forces, compression forces, and tension forces.
  3. Pectoralis fascia. The pectoralis major muscle is covered with a thin superficial membrane, the pectoral fascia, which has many prolongations intercalated among its fasciculi ; at the midline, it is attached to the front of the sternum, above it is attached to the clavicle, while laterally and below, it is continuous with the fascia.
  4. Suspensory ligaments. The subcutaneous layer of adipose tissue in the breast is traversed with thin suspensory ligaments that extend obliquely to the skin surface, and from the skin to the deep pectoral fascia. The structural stability provided by the Cooper's ligaments derives from its closely packed bundles of collagen fibers oriented in parallel; the principal, ligament-component cell is the fibroblast, interspersed throughout the parallel collagen-fiber bundles of the shoulder, axilla, and thorax ligaments.
  5. Glandular tissue. As a mammary gland, the breast comprises lobules and the lactiferous ducts, which widen to form an ampulla at the nipple.
  6. Adipose tissue. The fat tissue of the breast is composed of lipidic fluid that is 90–99 per cent triglycerides, free fatty acids, diglycerides, cholesterol phospholipids, and minute quantities of cholesterol esters, and monoglycerides; the other components are water and protein.
  7. The skin envelope. The breast skin is in three layers: the epidermis, the dermis, and the hypodermis. The epidermis is 50–100 μm thick, and is composed of a stratum corneum of flat keratin cells, that is 10–20 μm thick; it protects the underlying viable epidermis, which is composed of keratinizing epithelial cells. The dermis is mostly collagen and elastin fibers embedded to a viscous water and glycoprotein medium. The fibers of the upper dermis are thinner than the fibers of the deep dermis, thus the skin envelope is 1–3 mm thick. The thickness of the hypodermis varies from woman to woman, and body part.