Biomedical Engineering Reference
In-Depth Information
with this device (40). Of note, this product has not received
FDA clearance for usage on the body at the time of this writing
(January 2013).
Prior to treatment, the skin surface is cleansed and dried.
Glycerin oil is applied to the treatment area and then the treat-
ment head is glided across the skin surface in either circular or
linear strokes. Erythema and warmth during treatment is
expected. Skin temperature should be monitored with an IR
thermometer to prevent surface temperatures rising above
40-42°C; once the target temperature is obtained (40), treat-
ment is continued for an additional 2 minutes (41). Treat-
ments are administered weekly for 6-8 weeks, and monthly
maintenance treatments are encouraged. Adverse events
include erythema (although expected and transient), burn,
bruising, and mild discomfort during treatment (40).
The only study on cellulite was performed by Manuskiatti
on 39 patients with mild-to-severe cellulite involving the arms,
abdomen, buttocks, or thighs. Treatments were administered
weekly for eight treatments using 20-28.5 W total per treat-
ment. Thirty-seven patients (81 anatomic sites) completed the
study. One month after the fi nal treatment session, nearly a
50% mean improvement in the clinical appearance of cellulite,
as graded by a blinded investigator, was discovered (41).
In a study using classic and high-frequency ultrasound to
evaluate the effectiveness of another tripolar RF device, the T1
Tripolar RF Beauty Machine (Beauty Light Science and Tech-
nology Co., Ltd., Beijing, China) for anticellulite treatment,
cellulite was reduced in 89.27% of the 28 women who under-
went treatment (42). Eight treatments were administered
weekly. Ultrasound images were taken before initiating ther-
apy and 4 weeks after the last treatment. The following struc-
tures were evaluated using high-frequency ultrasound:
epidermal thickness, dermal thickness, dermal echogenicity,
the length of the subcutaneous tissue bands growing into the
dermis, and the presence/absence of edema. When compared
with the placebo group (
n
= 17), there was statistically signifi -
cant reduction in both epidermal and dermal thickness in the
RF-treated group (
p
= 0.006). There was also a statistically sig-
nifi cant increase in dermal echogenicity, decrease in the length
of the subcutaneous tissue bands growing into the dermis, and
decrease in the presence/absence of edema, as well as decrease
in the stage of cellulite as measured by Nurnberger-Muller
scale (
p
temperature. This makes it possible to thermally subscise
hypodermal septa, thermally denature adipocytes protruding
into the dermis, stimulate neocollagenesis at the dermal-
hypodermal junction, resulting in thickened and tightened
skin, and selectively melt hypodermal adipocytes in the risen
areas of the skin (43). Of note, this product has not received
FDA clearance at the time of this writing (September 2011).
Prior to treatment the skin is marked with the patient stand-
ing. The target area is divided into square sectors (5 cm × 5 cm)
and each sector is treated individually. The treatment area is
anesthetized with tumescent lidocaine solution. The laser can-
nula is inserted via an incision made with a trocar or blade
close to the target area. A red aiming beam from an He:Ne laser
source allows one to visualize the tip of the fi ber during treat-
ment. The cannula is gently positioned below the skin surface
and the procedure is then divided into three steps, with the
fi ber in the
down
,
horizontal
, and
up
positions. The fi ber is fi rst
placed in the
down
position (1-2 cm beneath the skin), once in
place the cannula-fi ber unit is moved back and forth in a fan-
like pattern until the delivered energy totals 300-600 J. When
all selected raised sectors are treated, the fi ber position is
changed to
horizontal
direction, with the side-fi ring energy
parallel to the skin surface (rather than perpendicular). In this
step, energy is delivered only to areas premarked as dimples,
with the horizontal fi ber moving in a fan-like pattern and in
the same plane. The end point in this second step is loss of
resistance as the cannula passes through the tissue, indicating
that the septa no longer connect the dermal and muscle layers.
The fi ber is then set at
up
and positioned 2-3 mm below the
skin surface, just under the dermal-hypodermal interface. All
sectors are then uniformly treated. Total treatment time
(including pretreatment and posttreatment care) is approxi-
mately 90 minutes, depending on the area treated. Once the
laser treatment is complete, the liquefi ed adipocytes are
removed by gently squeezing the incision point tissue. Stan-
dard pressure dressings are applied to the treated areas, and
patients are instructed to wear a compression garment for 2 to
3 weeks. Results from treatment can persist for up to 1 year
(43). Adverse events include mild discomfort, bruising, swell-
ing, and numbness, which typically resolve after 3 months (43).
In a study on 10 healthy women with moderate-to-severe
cellulite involving their thighs (lateral, posterior, or both), par-
ticipants received a single treatment with the CelluLaze system
to one thigh, while the other served as a control, using power
settings at 8-10 W and pulse frequency at 40 Hz (43,44). Sur-
face temperatures reached 40°C and 42°C during treatment.
Delivered energy ranged from 300 J for raised areas and dim-
ples measuring 3 cm × 3 cm to 600 J for raised areas and dim-
ples measuring 5 cm × 5 cm. An average subdermal temperature
below 47°C was monitored and maintained by a temperature-
sensing cannula (ThermaGuide, Cynosure, Inc.) attached to
the laser cannula. To ensure uniform delivery of energy during
treatment, an accelerometer (SmartSense A, Cynosure, Inc.) is
attached to the laser hand piece, which causes the energy level
to decrease (if the motion of the hand piece is slowed) or
increase (if the hand piece is moved more rapidly); if the hand
piece stops moving, energy delivery ceases within 0.2 seconds.
Mean skin thickness (as shown by ultrasound) and skin elas-
ticity were shown by objective measurements to increase sig-
nifi cantly at 1, 3, 6, and 12 months. Subjective physician and
0.001). The placebo group showed no statistically
signifi cant changes in the above parameters. This device is not
FDA approved for use in the USA.
≤
Laser Energy Devices
Cellulaze
Cellulaze (CelluLaze, Cynosure, Inc., Westford, Massachusetts,
USA) is a pulsed laser that delivers 1440-nm energy internally
to the dermal-hypodermal interface via a fi ber. Energy is
delivered to the subdermal tissue through a 600-µm “side-fi r-
ing” fi ber (SideLight 3D, Cynosure, Inc.) enclosed in a 1-mm
cannula and extending 1-2 mm beyond the distal end of the
cannula. The side-fi ring fi ber delivers approximately half its
laser energy perpendicular to the fi ber axis as the other
half moves forward along the axis. The transient bubble on
the distal tip creates an air-glass interface in the tissue
and defl ects the beam. A thermal camera ThermaCAM E45,
FLIR, Niceville, Florida, USA) is used to monitor skin surface
