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and forefinger during local anesthesia infiltration,
laser energy delivery, and lipoaspiration. Limiting
exogenous water infiltration to 3 mL minimizes
distortion of the anatomy during treatment and fa-
cilitates endpoint identification but also limits
thermal confinement. The fatty tissue ablation
efficiency of the micropulsed 1444-nm Nd:YAG
interstitial fiber laser, however, enables sufficient
local tissue effect with preserved thermal confine-
ment within the suggested total energy usage
parameters.
The local anesthetic mixture that the author fa-
vors includes 0.5% lidocaine; 0.25% Bupivacaine
hydrochloride; and 1:200,000 epinephrine and
hyaluronidase, 2 to 4 IU per mL (eg, Hylenex re-
combinant, Halozyme Therapeutics, San Diego,
CA, USA). Initially, approximately 1.0 mL of this
local anesthetic mixture is used to provide anes-
thesia to the percutaneous entry site and the
intervening tissue toward the LAFC treatment
zone as well as a field block that includes the tis-
sue for debulking and contouring. A narrow (eg,
21-gauge) multihole infiltration cannula is then
used to deliver 3 mL of local anesthetic to the
LAFC treatment area.
With the thermally confined micropulsed
1444-nm Nd:YAG interstitial fiber laser, energy de-
livery occurs via a 600-
m
m silica multimode fiber
with the fiber used either free (bare) or assembled
with a disposable or nondisposable cannula. Prior
studies have demonstrated general safety guide-
lines for energy delivery during LAFC of the lower
face when using the micropulsed 1444-nm
Nd:YAG interstitial fiber laser and minimal volume
local anesthesia (dry technique)—typical parame-
ters include power 5.4 W, pulse energy 180 mJ,
pulse duration 100
m
s (fixed), pulse rate 30 Hz,
and total energy delivered 200 to 300 J.
1,7
Although the unique thermal signature of the
micropulsed 1444-nm Nd:YAG interstitial fiber
laser enables safe treatment without the need for
internal or external temperature monitoring, it is
important to keep the fiber continuously moving
through the tissue during active lasing—this facili-
tates even distribution of laser energy and limits
the potential for clinical thermal confinement fail-
ure. Certainly some latitude exists with regard to
these treatment parameters; however, in a prior
study of mid- and lower face LAFC, complications,
such as prolonged inflammatory edema and over-
correction, were associated with faster energy de-
livery (40 Hz) and with a doubling of the total
energy delivered (eg, 500 J).
1
Immediately after
energy delivery, a similar volume (eg, 3 mL) of
room temperature sterile saline is infiltrated into
the treatment area as a postcooling or thermal
quenching step that attempts to minimize collat-
eral thermal spread to adjacent tissues as well as
reduce PIE.
Removal of emulsified tissue and liquefied fat via
manual lipoaspiration with a small dual port aspira-
tion cannula (eg, 19 gauge) and a 6-mL syringe
(prefilled with 1-mL sterile saline) enables definitive
tissue contouring.
Fig. 2
shows the full minimal
instrumentation requirement for LAFC. It is not un-
common for a small-diameter aspiration cannula
to become blocked with fibrous tissue during
lipoaspiration—when this occurs, the cannula is
Fig. 1.
(
A
) Preoperative view of LAFC treatment area with lower facial fullness and jowling in a 58-year-old
woman in upright seated position. (
B
) Intraoperative view of LAFC treatment area in the same patient in 20
reverse Trendelenburg position. LAFC treatment zone is outlined with purple marker. LAFC entry site is located
approximately 2 cm posterior to inked posterior extent of LAFC treatment zone and 2 cm above the caudal
mandibular margin. The 600-
m
m bare laser fiber is present at the LAFC entry point and the red aiming beam
at the fiber tip is seen faintly between the surgeon’s gloved thumb and index finger. Note that the laser fiber
is engaged in fatty tissue at the superior extent of the jowl fat compartment.
Holcomb