Biomedical Engineering Reference
In-Depth Information
50 original study subjects showed roughly a 25-33% and
36-46% hair reduction at a mean follow-up of 20 months after
one or two treatments (9-mm spot size, pulse duration of
5-20 ms, fl uences of 15-40 J/cm
2
, single or triple pulsed),
respectively, with an LPDL device (33). Eremia et al. in a head-
to-head trial comparing an LPDL to a long-pulsed alexandrite
laser found a 49-94% hair reduction at 1-year follow-up after
four treatments (9-mm spot size, pulse duration of 20 ms, fl u-
ences of 12-40 J/cm
2
) (34) with the LPDL in 15 subjects. Simi-
lar results were achieved with the alexandrite laser used in this
study. Fifteen of 20 subjects with Fitzpatrick skin phototypes III
and IV treated with a long-pulsed alexandrite laser (12-
and 18-mm spot size, 3-ms pulse duration, fl uences of 20 or
40 J/cm
2
) or a long-pulsed Nd:YAG laser (12-mm spot size,
3-ms pulse duration, fl uence of 40 J/cm
2
) for four sessions at
8-week intervals showed 76-84% and 74%, respectively, hair
reduction 18 months after the last treatment (29). Braun reported
a head-to-head trial of a high fl uence LPDL (9-mm spot size,
pulse duration of 30 ms, fl uences of 20-50 J/cm
2
) versus a low
fl uence LPDL (12 × 10 mm spot size, pulse duration of 20 ms,
fl uences of 5-10 J/cm
2
) in 22 subjects and showed similar, 94%
and 90%, respectively, hair reduction at 18-month follow-up
following fi ve treatments spaced 6-8 weeks apart (48). Finally,
we recently reported statistically signifi cant hair clearance, 54%
and 42%, at 6- and 15-month followup visits following three
monthly treatments using an LPDL using a large handpiece in
the largest prospective trial to date (44). Remaining hairs were
found to also grow back less thick and lighter.
case studies
Case 1
A 37-year-old woman was diagnosed with polycystic ovary syndrome (PCOS). Her symptoms of PCOS are as follows: infrequent
menstrual periods; increased growth of hair on the face, fi ngers and toes; oily skin and acne; obesity; and type 2 diabetes. Current
therapy consists of maintaining a healthy weight and treatment of her diabetes with insulin. Although the male hormones are
elevated, she refuses to take any androgen-blocking drugs. She consulted for treatment of her facial hirsutism, characterized by
increased growth of black terminal hairs in the submandibular area, which she shaves daily (Fig. 5.4A). She was looking for a more
effi cient treatment modality of hair removal. As this patient was diagnosed with an underlying endocrine abnormality, she was
alerted to the potential limitations of LHR treatment. Initially, she was treated with an 800-nm diode laser [LightSheer, Lumenis
(San Jose, California, USA)] at 30-35 J/cm
2
, 30 ms, and a 12 × 12 mm spot. Once the regrowing hairs became lighter and fi ner,
treatment was continued with a 3 ms, 755-nm alexandrite laser [GentleLase, Candela (Wayland, Massachusetts, USA)] 8-mm, at
40 J/cm
2
for an 8-mm spot with dynamic cooling device (DCD) cooling (30 ms on, 30 ms off time).
The patient underwent eight treatment sessions in total, at 2- to 3-month intervals. A very satisfying result with 90% reduc-
tion of the hair regrowth was obtained (Fig. 5.4B). Because of the continued hormonal stimulation, she continues to be
treated once a year for the few regrowing hairs.
(
A
)
(
B
)
Figure 5.4
(
A
) Patient with hirsutism due to polycystic ovary syndrome. (
B
) Signifi cant reduction of hair growth at 9 months after the eighth laser hair
removal treatment.
Case 2
A 44-year-old female patient consulted for LHR of her axillae (Fig. 5.5A). Previous treatment modality consisted of shaving
or the use of depilatory creams. She received four treatments with an 800-nm LightSheer diode laser (30 ms, 30 J/cm
2
,
12 × 12 mm) and one fi nal treatment of the remaining fi ne, regrowing hairs with a 3-ms, 755-nm GentleLase, alexandrite laser
(40 J/cm
2
, 8-mm spot, 30/30 DCD cooling). Except for a few occasional regrowing hairs, a very satisfactory result was obtained
5 years after the last treatment (Fig. 5.5B).
