Hamilton–Norwood scale

The Hamilton - Norwood scheme divides the androgenetic hair loss ( androgenetic alopecia ) of the man in different stages, which are ( I to VII ) associated with seven levels. Was developed during this schematic classification in 1951 by Hamilton. Norwood modified and expanded it in 1975. Approximately 80 percent of affected men the training of the Bald of the given classification follows. The Hamilton - Norwood - scheme allows a standardized medical documentation of hair loss. It is applied, among others, in the study of affected and hair transplants.

A derivative of it, three-stage scheme was published by Ludwig in 1977. It describes a more diffuse hair loss around the central apex region, which is typical of androgenetic hair loss in women, but also occurs in approximately one fifth of the men involved.

Stadiums

The typical course of androgenetic hair loss begins temporal ( at the temples ) and frontal (on the forehead). Later, the hair also thins in the region of the vertex (top back of the head ) until the bald area eventually extends over the entire cranium of time. A fringe of hair from above the ears around the entire back of the head around is usually preserved.

• Type I: No or very low in retreating, the frontal hairline.
• Type II: hair loss frontal and temporal, training of triangular regions without hair at the temples ( receding hairline ), does not go beyond a two inches from the outer ear canals imaginary connecting line.
• Type III: a receding hairline rich posteriorly (towards back of the head ) beyond the imaginary front of the ear canals connecting line; Minimum level for " baldness ".
• Type III (vertex or vertices ): Hair loss, especially in the crown area, frontal hair loss usually in stage I or II, stage III not exceed.
• Type IV: Further hair loss in the crown area, frontal hair loss exceeds stage III zones are separated by a clear hair band.
• Type V: Zones of distinct frontal hair loss on the vertex and are separated only by a narrow zone of the hair, the hair on the temporal and occipital takes " horseshoe " (even type VI and VII)
• Type VI: Areas of hair loss in the frontal and parietal region have merged, lateral ( aspiring to the sides ) propagation of the hairless areas.
• Type VII: Of the original hair growth leaving only a narrow band that runs from the ear to the back of the head.

For type II to V, there is a division into A- and V- types. In the A- variants there is only one straight line progresses, frontal hair loss; at the V variants hair fades additionally in the area of the vertex. An attempt to explain the typical sequence of hair loss is the power loss of hair.