Male pattern baldness (MPB), also known as Androgenetic alopecia , is one of the most common conditions affecting men. In the United States alone there are over 35 million men who experience visible hair loss.
Hair typically begins to thin in the temples and crown and gradually progresses over time. this progression can vary being rapid in some men and slower in others.
No matter how severe the hair loss, hair is not lost at the back or sides of the head. These regions are genetically different from hair follicles found in the front and top of the head. The hair at the back and sides of the head can be harvested and transplanted to bald or thinning areas and continue to grow as they would on the side and back of the head.
Norwood Classification Chart for Male Pattern Baldness
The Norwood Classification Chart will give you an idea about what stage of hair loss you may have. The chart is the standard classification for the most common types of male pattern baldness. Although it is useful to determine what stage of baldness you approximate, most patients will not fit perfectly into any category, nor are stages necessarily progressive for each patient.
Represents the minimal extent of hair loss considered sufficient to represent baldness. Scalps have deep frontal temporal recessions, which are usually symmetrical and are either bare or sparsely covered.
TYPE III VERTEX
Hair loss is chiefly in the vertex. There may be some frontal recession, but does not exceed that seen in Type III. This type of baldness is most common with advancing age, but, in some patients, may occur early and occasionally precede significant front loss.
The frontal and temporal recession is more severe. There is a sparseness or absence of hair on the vertex area. These areas are extensive, but are separated from each other by a bridge of moderately dense hair. Should not be confused with Type III Vertex in which the loss is primarily on the vertex.
The vertex region of alopecia remains separated from the frontal temporal region of alopecia. The separation is now not as distinct because the band of hair across the midscalp has become narrower and sparser. Both the vertex and frontal temporal areas of alopecia have become larger.
The bridge of the hair that crossed the midscalp in the previous type is now gone. The frontal temporal and vertex regions of alopecia have become confluent; in addition, the entire area of alopecia has increased laterally and posteriorly.
This is the most severe form of male pattern baldness. All that remains is a narrow horseshoe shaped band of hair that begins laterally just anterior to the ear and extends posteriorly on the sides. This hair is usually not dense and is frequently fine.