This brief article will discuss the regions of the crown and why they are important when designing a crown for hair transplantation. The crown can be divided into three geographic zones that run like bands across the scalp: the vertex transition zone, or vertex transition point; the upper arc; and the lower arc. The vertex transition point (VTP) occurs where the scalp transitions from the vertical plane of the crown to the horizontal plane anteriorly of the posterior midscalp. The hair angles in the VTP aim primarily forward with a bit of slight splaying outward toward the side edges. However, there is almost no whorl at this point, as almost all the hairs are angling forward. The upper arc is the arbitrary upper half of the crown that begins above the center of the whorl; and the lower arc is the arbitrary lower half of the crown that begins below the center of the whorl.

The VTP and the upper arc are the most important areas to create visual density, a fact that will be mapped out more in detail in the coming blog articles in this series. The VTP is the area that can look particularly bald because light tends to strike and cast a bald appearance at the transition from the vertical to the horizontal plane of the scalp. Therefore, stronger grafts across the VTP are very important. The upper arc is just as important since the grafts in the upper arc sweep up to cover the VTP and sweep down to cover the lower arc. Therefore, the upper arc is a priority in terms of graft density and stronger graft size. The lower arc tends to be a less important area since it does not impart as much visual punch and also does not cover anything other than non-balding scalp. Accordingly, understanding these geographic terms can be very helpful for a surgeon who is planning to allocate grafts for optimal aesthetic impact.

Samuel M. Lam, MD, FACS is a board certified hair restoration surgeon in Dallas, Texas. To learn more about Dr Lam’s crown hair transplant procedures please visit our website hairtx.com or call 972-312-8105 to schedule a consultation.