In the past, surgeons have had 2 techniques with which to improve facial bony contour: osteotomy with mobilization of facial bony segments and placement of implants (foreign-body materials or autologous cartilage or bone) over the bone, under the soft tissue. In this article, we discuss a relatively new third alternative, the use of microfat grafts. Facial prebone contour augmentation can be obtained through the use of microfilling to thicken soft tissue adjacent to facial bones. The anatomic areas that can be augmented and contoured with the use of this technique include the malar, paranasal, chin, and mandibular regions.

In this article, we review the medical records and outcomes of 32 patients who underwent facial prebone contour augmentation with microlipofilling, performed at the Jalisco Plastic and Reconstructive Surgery Institute or the Guerrerosantos Plastic Surgery Clinic, between 1995 and 2002.

Preoperative planning

Patient evaluation

Before surgery, all patients underwent a thorough, individualized preoperative evaluation, including frontal, basilar, and oblique views and photographic and radiologic studies, to establish an accurate diagnosis. In this examination, flat or thinned facial bony contours were identified, asymmetries were evaluated, and the amount of contour augmentation to be performed was estimated. This evaluation permitted the selection of those patients for whom augmentation of the malar, paranasal, chin, and mandibular regions was appropriate and in some cases identified the need for additional procedures, such as removal of the buccal fat pad and neck lipoplasty.

With the patient seated, the areas to be augmented were marked before surgery to facilitate intraoperative evaluation of the contour of areas of flat or thinned bony contour. It was important to mark flatness in 3 dimensions to accurately determine the tissue requirements with respect to both surface area and volume. Generally, thinned soft tissues in the mandibular region are about 0.5 cm thick. Infiltration of fat grafts was aimed at producing a soft-tissue thickness of 1.5 cm. In other facial anatomic areas, such as the malar, paranasal, and chin areas, measurement of soft tissues was performed while the patient was under intravenous sedation, before infiltration of the local anesthetic. A 20-gauge needle was introduced vertically toward the surface of the bone until the tip of the needle touched the bone, and the depth was measured with a ruler.

Surgical technique

Each surgery was performed with the patient under intravenous infiltration of local anesthetic plus adrenaline into the donor areas of fat. Donor areas included any part of the body with excess fat, such as the abdominal wall or trochanteric region. In the past, we infiltrated the fat grafts after we performed the face lift, but currently we prefer to infiltrate microfat grafts before the local anesthetic is introduced and the face lift is performed, so that we can accurately judge the exact amount of fat to be grafted into each anatomic area. In addition, regional facial blocks to anesthetize greater facial areas were useful.

Fat was harvested from the donor area 10 minutes after infiltration. To harvest the fat, we used 10-mL syringes with 14-gauge needles. The syringes contained 3 mL of aspirated saline solution to mitigate the impact of the fat against the walls of the syringe during aspiration. We harvested just 5 mL of fat in each syringe. After the fat was harvested, we drew an additional 2 mL of saline solution into the syringe and washed the fat by performing maneuvers such as turning the syringe upside down multiple times. The saline solution was changed 4 or 5 times to obtain clean fat grafts without local anesthetic, blood, and oils.

The fat was then deposited in a medicine glass and fragmented in accordance with the methods of Carraway and Mellow.[1] We developed 3 techniques for fragmenting the fat. One consisted of introducing scissors into the medicine glass and making multiple cuttings until the fat was sufficiently fragmented. An alternative method was to introduce the fat into a small mill and fragment it in the same manner in which baby food is prepared. The third alternative, which is our preferred method, was to introduce the fat into a 5- to 10-mL syringe with thin needles (originally 18-gauge but later 20-gauge) and transfer it from the syringe into a medicine glass several times. Initially, the unfragmented fat frequently obstructed the conduit of the needle. After 10 minutes, the fat was usually sufficiently fragmented to be infiltrated with a 20-gauge needle. Microfat-graft preparation required additional trained personnel for assistance. If properly trained in the technique, 1 or 2 medical staffers, such as a registered nurse and a surgical assistant, were able to offer support that shortened the duration of surgery substantially. Usually we harvested approximately 80 mL of fat to arrive at a final volume of roughly 50 mL because approximately 30% of the normal fat cells were lost during preparation.

Fat grafts were applied to the face through a percutaneous approach utilizing 5-mL syringes with 18- or 20-gauge needles. We performed aspiration after introducing the needle but before infiltrating the fat grafts to avoid serious complications, such as embolus, by ensuring that the needle did not penetrate a vein or an artery.