INTRODUCTION
Numerous techniques exist for injecting facial fillers. The
specific technique used depends on a number of variables,
including the type of filler, the anatomic location
for the filler, and the preferences/experiences of the injector.
Hyaluronic acid fillers are used in various facial anatomic locations
to smooth contour irregularities and augment facial
features. The techniques used to inject hyaluronic acid fillers are
numerous and include linear threading, cross-hatching, fanning,
layering, depot injections, and the serial puncture technique.1
Another technique, the “tower-technique,” is a valuable addition
to the aforementioned injection techniques. The concept of
the tower technique is to create a tapering vertical tower of filler
material that serves as a scaffold for the overlying soft-tissue
structures (Figure 1). Whereas hyaluronic acid fillers are traditionally
placed in the deep dermis and superficial subcutaneous
fat, the tower technique aims to create a deep base of support
that extends through the entire subcutis.
The tower technique has advantages over other techniques
in certain anatomic areas, as the technique aims to fill the
desired area by reintroducing the lost structural support. This
technique can be used to correct the nasolabial folds and the
marionette lines. The tower technique can also be used to
revolumize the chin and the prejowl sulcus. Additionally,
volumization of the lateral brow can be achieved with the
hyaluronic acid towers.
The tower technique is appropriate for hyaluronic acid fillers. Fillers
such as calcium hydroxylapatite and poly-l-lactic-acid, which
require deeper anatomic placement or injection in a uniform
plane, are not amenable to this technique.
Anatomy and Age-Related Changes
Nasolabial Folds
The nasolabial fold is defined by a series of muscles, fat compartments, and fibrous septae. The contributing muscles include the orbicularis oris, the levator anguli oris, the levator labii superioris, the zygomaticus major, and the zygomaticus minor. The superficial nasolabial fat compartment is the most medial of the cheek fat compartments. The compartment is bounded superiorly by the orbicularis retaining ligament. The suborbicularis oculi fat (SOOF) serves as the superior lateral and deep boundary. The deeper medial cheek fat surrounds the levator anguli oris. It is bounded laterally by the zygomaticus major and the buccal fat pad. Septal barriers contribute to the delineation of these fat compartments and serve as the origin of the retaining ligaments that provide support for the facial soft tissue.2
The nasolabial fold is defined by a series of muscles, fat compartments, and fibrous septae. The contributing muscles include the orbicularis oris, the levator anguli oris, the levator labii superioris, the zygomaticus major, and the zygomaticus minor. The superficial nasolabial fat compartment is the most medial of the cheek fat compartments. The compartment is bounded superiorly by the orbicularis retaining ligament. The suborbicularis oculi fat (SOOF) serves as the superior lateral and deep boundary. The deeper medial cheek fat surrounds the levator anguli oris. It is bounded laterally by the zygomaticus major and the buccal fat pad. Septal barriers contribute to the delineation of these fat compartments and serve as the origin of the retaining ligaments that provide support for the facial soft tissue.2
The appearance of the nasolabial fold with advancing age is due
to a number of factors. The aging face needs to be viewed as
a compartmentalized but inter-related three-dimensional structure.
The nasolabial folds appear where thick superficial fat
transitions to thinner superficial fat. However, loss of volume—
