Tubular Breast Deformity (TBD) is a congenital condition affecting the shape and structure of the mammary glands. It is recognized by an unusual growth pattern that becomes apparent during puberty when the breasts begin to develop. TBD is characterized by an abnormal restriction of the breast tissue that prevents the expected rounded expansion, distinguishing it from simply having small breasts.
Defining the Physical Characteristics
The defining feature of TBD is the constricted base of the breast, where the diameter at the chest wall is noticeably narrow, giving the breast a tube-like appearance. This constriction results in a significant lack of tissue fullness, particularly in the lower pole. The typical rounded contour is replaced by a conical or tubular shape, often resulting in a higher positioning of the inframammary fold, the crease beneath the breast. Another characteristic is the protrusion of breast tissue through the areola and nipple complex. This causes the areola to appear puffy, enlarged, and disproportionate to the size of the breast.
Underlying Causes of Development
TBD is a congenital abnormality, present from birth, though physical signs only manifest when hormonal changes trigger breast development during adolescence. The primary mechanism involves a restrictive ring of fibrous connective tissue, or fascia, at the base of the breast. This constricting band prevents the developing glandular tissue from expanding radially across the chest wall. While the exact triggers remain uncertain, current theories point toward collagen deposition issues or a genetic predisposition affecting the elasticity of this fascial layer. The inability of the tissue to expand outward forces the breast tissue to grow forward, creating the characteristic tubular shape.
How the Deformity is Classified
The condition’s severity is categorized using classification systems to guide treatment planning. The Grolleau Classification divides the deformity based on which breast quadrants are affected by tissue deficiency.
Type I, the mildest form, involves underdevelopment of only the lower medial quadrant. Type II involves a deficiency in both the lower medial and lower lateral quadrants, leading to a more pronounced lack of fullness. The most severe forms, Type III and Type IV, involve underdevelopment of all four quadrants, resulting in global breast constriction and minimal breast base.
Surgical Correction Methods
Surgical correction is the primary treatment for TBD and requires addressing the underlying anatomical restrictions. The first step involves releasing the constricting fibrous ring at the breast base to allow for expansion. This is typically achieved through internal incisions, such as radial scoring of the glandular tissue, which promotes the outward spread of the breast tissue.
Following the release of the constriction, the surgeon addresses the lack of volume in the lower breast pole and redistributes existing tissue. Techniques like glandular flaps or autologous reconstruction move available tissue into the deficient lower quadrants. This is often combined with a procedure to reduce the diameter of the enlarged areola, usually through a circum-areolar incision, which also helps reposition the nipple-areola complex.
To achieve a natural, rounded shape and sufficient volume, the procedure almost always includes volume augmentation. This can be accomplished by placing a breast implant. Alternatively, a surgeon may use fat grafting, which involves harvesting and injecting fat into the breast to provide a softer contour. In severe cases with very tight skin, a two-stage approach may be necessary, involving a temporary tissue expander placed first to gradually stretch the skin before the final implant is inserted.