Vol 21, No 4 ~ Low Level Laser

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Vol 21, No 4 ~ Low Level Laser Powered By Docstoc
					          NLN

NATIONAL LYMPHEDEMA NETWORK
                                 LYMPHLink Article Reprint
                                Volume 21, No. 4                                         October ~ December 2009

An Assessment Of The Role Of Low-Level Laser
Therapy In The Treatment of Lymphedema
By Jeffery R. Basford MD, PhD and Andrea L. Cheville MD, MS




L
       ight has been used to treat        Scientific Background                      energies involved in treatment should
       disease since the dawn of time.                                               be low (between 1-4 J/cm2). Most
       Nevertheless, its popularity has   and Support                                devices, in fact, are relatively low-
       fluctuated over the years.            As noted above, LLLT involves           powered and have outputs between
Early use, such as that recorded          the application of low powers and          30 and 500 mW (power). Treatment
by the Greeks and Romans,                 energies of laser irradiation to tissue    typically is delivered at multiple sites
emphasized its thermal effects and,       with the goal of producing benefits        with the laser applicator in contact
as recently as the early 1900’s, the      by non-destructively altering cellular     with the skin, or in a noncontact
Nobel Prize in Physics was awarded        or tissue function. Early lasers were      approach in which the beam is
for the use of the ultraviolet portion    gas-filled devices (e.g., helium and       scanned over the area to be treated.
of the light spectrum in the treatment    neon, krypton and argon), but by           While attention may be placed on
of tuberculosis. Subsequent               the 1980s these instruments began          waveform of a device’s output,
improvements in medical care,             to be replaced with cheaper and            evidence supporting the benefits of
however, led to a gradual decline         easier to use superluminous diodes.        a specific pattern of pulsing over a
and near extinction of interest in the    Today, diode use prevails and with         simple continuous wave is limited.
therapeutic use of light.                 the exception of some helium-neon
   The invention of the laser (Light      lasers, most “laser treatments” are
                                          in reality performed with individual or
                                                                                     Safety and Benefits
Amplification by Stimulated Emission
of Radiation) in the early 1960’s         groups of Gallium-Arsenide (GaAs)             LLLT, by definition, involves low
led to a new attention to light’s non-    and Gallium-Aluminium-Arsenide             amounts of energy and no risk of
thermal capabilities and a reversal       (GaAlAs) diodes.                           thermal injury. While some have
of this trend. At the heart of this          While laser and diode radiation         raised the thought that stimulation
interest was the belief that specific     might have therapeutic benefits, the       could accelerate cancer growth, this
wavelengths of light (i.e. colors)        conditions most likely to respond          issue remains theoretical. As a result,
at intensities too low to increase a      and the extent of these benefits           safety concerns related to LLLT are
tissue’s temperature more than a          remain areas of active investigation.      low and adverse effect reports rare.
few tenth’s of a degree can alter         The answer to the first question, why      In fact, an attractive aspect of LLLT is
cellular and tissue activities. Initial   these devices may have benefits, is        that treatment does not raise tissue
work began in Eastern Europe and          now generally accepted to be that as       temperature significantly. Therefore,
focused on the treatment of non-          their radiation is purer (in other words   LLLT can be used during the acute
healing wounds.                           has a narrower bandwidth) than             stages of an injury or in conditions
   The next few decades saw a             light from other sources, it is more       for which heat might be expected to
rapid expansion of interest and           capable of producing wavelength-           worsen swelling or inflammation.
a variety of names applied to the         dependent resonant frequency                  Soft tissue and musculoskeletal
approach. Although terms such as          interactions with cell organelles          injuries have proven particularly
Biostimulation, Cold Laser and Low        such as the mitochondria. There is         intriguing as these sites tend to
Intensity Laser have been used,           also a general, but not universal,         be superficial and LLLT is claimed
nowadays, Low Level Laser Therapy         acceptance that multiple treatments        to have both analgesic and tissue
(LLLT) is the most generally              are necessary, that the treated            healing effects. Laboratory studies
accepted term.                            tissue must be under stress, and the       support the concept that LLLT can
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 Infoline: 1-800-541-3259 • Tel: 510-208-3200 • Fax: 510-208-3110 • Email: nln@lymphnet.org • Website: www.lymphnet.orgm

                                                      PAGE   1   OF   3
increase collagen production,               and weaknesses.                              Kaviani and colleagues reported
alter DNA synthesis, reduce the                For example, a recent study by         in 2006 on a small double-blind
expression of inflammatory markers,         Kozanoglu and colleagues reports          controlled trial in which 11 women
and enhance the function of                 on 47 women with post-mastectomy          with post mastectomy lymphedema
damaged muscles and nerves.                 edema following modified radical          were assigned to either receive
Extension of these effects to animals       mastectomies and axillary                 890 nm radiation over the axilla
and humans has proven more                  dissections. Subjects were                and arm from a GaAs laser device
difficult to establish. Although many       randomized to receive either twenty       or identical treatment with a sham
investigations find benefits from           2-hour sessions of pneumatic              device. Evaluation of the eight who
LLLT in a variety of musculoskeletal,       compression therapy or twelve             completed the treatment over a 22-
arthritic, soft tissue, and painful         20-minute sessions of LLLT over the       week period revealed improvement
conditions, differences in their            antecubital fossa and axilla with a       in both groups. The authors noted
designs, parameter choices, and             904nm infrared pulsed Ga-As laser         the improvements tended to be
subject populations make it difficult       device over a four-week period. All       more pronounced in subjects treated
for systematic and meta-analytic            subjects received a home program          with the active device. The authors
studies to confirm LLLT’s clinical          of daily exercise, range of motion        concluded that their results were
benefits. Fortunately, study designs        and skin care. The investigators          encouraging but that further research
are improving and the existence of          found that while both groups showed       was needed.
a growing number of larger, well-           significant improvements in their limb       Piller and Thelander provide two
designed studies may change the             circumferences following treatment,       reports of a group of 10 women with
current situation. Similarly, a frequent    those improvements in the LLLT            post-mastectomy lymphedema who
lack of a head-to-head comparison           group tended to be larger and more        underwent an uncontrolled 10-week
with alternative treatments such            prolonged in the study’s impressively     trial involving sixteen treatments with
as ultrasound and massage often             long, 1-year follow-up period. No         a laser which was scanned over the
complicates assessment of                   significant inter-group differences       treated area rather than held at a
clinical utility.                           were noted in terms of pain relief or     number of fixed positions. Evaluation
                                            grip strength.                            at the end of treatment revealed a
Lymphedema                                     Carati and colleagues reported         roughly 20% reduction in volume, as
   Lymphedema, at first blush, might        in 2003 on a rather complex trial in      measured by limb circumference.
not appear to be particularly amen-         which 61 women with breast cancer-        Follow-up of seven of these subjects
able to LLLT, given past emphasis on        related arm lymphedema were               indicated by self-assessment that
its use to promote healing and to           divided into groups receiving either      their limb volume improvements
alleviate musculoskeletal dysfunction       nine sessions of pulsed 904 nm            persisted.
and pain.Nevertheless, while still in its   irradiation at 17 sites along the            White and colleagues recently
early days, the idea that LLLT might        axilla over a 3-week period, or an        published an abstract describing
be beneficial may not be far-fetched,       identical placebo treatment with an       a randomized trial that compared
given its docu-mented effects on            inactive device. At the end of            LLLT to “standard care” for the initial
processes as diverse as protein             this trial, a second experiment was       treatment of breast cancer-related
and prostaglandin synthesis, cell           performed comparing the relative          lymphedema. The 148 participants
membrane transport, inflammation            benefits of one versus two courses        received either two weeks of LLLT or
and intra-cellular metabolism. In fact,     of radiation.                             decongestive therapy. A statistically
a number of investigators have                                                        significant reduction in arm circum-
reported reductions in swelling and         Interesting and                           ference relative to the control group
improved comfort following treat-           Related Findings                          was noted after LLLT in participants
ment. As is true for LLLT in general,          The investigators reported two         with mild but not moderate lymph-
the initial studies, while intriguing,      interesting and related findings: while   edema. It should be noted that while
are too small and frequently too            a single course of treatment had no       the results are intriguing, conclusions
poorly designed to do more than             effect on their subjects’ lymphedema,     and generalization are limited, as
suggest benefits. Subsequent work           two courses did; and the benefits         bandages were not worn between
has been marked by improving                became noticeable at follow-up            therapy sessions in the decongestive
designs and while the amount of             one month after the completion of         group and details about the nature
research completed is still limited, it     treatment. No effects on range of         of LLLT were not provided in this
is worthwhile to review its strengths       motion were noted.                        preliminary report.
  National Lymphedema Network, Inc. • 1611 Telegraph Avenue • Suite 1111 • Oakland, California 94612-2138m
  Infoline: 1-800-541-3259 • Tel: 510-208-3200 • Fax: 510-208-3110 • Email: nln@lymphnet.org • Website: www.lymphnet.orgm

                                                        PAGE   2   OF   3
Summary                                    decongestive therapy (CDT) remains              Alinagi-zadeh MR, Ataie-Fashtami.
                                           uncertain. Until rigorous trials permit         Low-level laser therapy in manage-
                                           therapeutic comparison of CDT and               ment of postmastectomy lymphedema.
   This paper has provided an
                                           LLLT, patients should be informed               Lasers in Medical Science. 21(2):
overview of LLLT and the relevance of
                                                                                           90-4, 2006
its research findings to lymphedema.       that LLLT does not eliminate their
A number of observations are               need for phase II CDT maintenance               Carati CJ, Anderson SN, Gannon BJ,
possible. The first is that the evidence   treatments.                                     Piller NB. Treatment of postmastectomy
supporting the use of LLLT in its                                                          lymphedema with low-level laser therapy:
                                           REFERENCES                                      a double blind, placebo-controlled trial.
initial areas of pain and musculo-
skeletal applications is promising,        Mester E, Spiry T, Szende B, and Tota J.        Cancer. 98(6):1114-22, 2003 Sep 15.
but still limited by heterogeneity         Effect of laser rays on wound healing.          Clinical Trial.
in study designs (with studies             American Journal of Surgery, 1971               Piller NB and Thelander A. (1998)
characterized by small sample              122(4): 532-5.                                  Treatment of chronic postmastectomy
size with limited follow-up in many                                                        lymphedema with low level laser therapy:
                                           Bjordal, J.M., M.I. Johnson, et al. (2007).
cases), irradiation and outcome                                                            a 2.5 year follow-up. Lymphology
                                           “Short-term efficacy of physical interven-
measures. The second is that the                                                           31:274–86
                                           tions in osteoarthritic knee pain. A
study of the application of LLLT to        systematic review and meta-analysis of          Piller NB and Thelander A. (1996) Low
lymphedema is following a pattern          randomised placebo-controlled trials.”          level laser therapy: A cost effective
similar to that of LLLT as a whole:        BMC Musculoskelet Disord 8: 51.                 treatment to reduce post mastectomy
small, uncontrolled studies (e.g.,                                                         lymphoedema. Lymphology 29:suppl 1,
                                           Chou, R. T. and L. Barnsley (2005).
Piller and Thelander) followed by                                                          297–300.
                                           “Systematic review of the literature of
larger and better designed trials such
                                           low-level laser therapy (LLLT) in the           White K, Fethney J, Hodges L, Grant J,
as that by Carati and colleagues.          management of neck pain.” Lasers Surg           Olver D. Lymphoedema Secondary to
The results are encouraging, but           Med 37(1): 46-52.                               Breast Cancer: A Randomised Controlled
the pool of evidence is limited and
                                                                                           Trial of Low Level Laser Therapy (Lllt).
further work by multiple investigators,    Kozanoglu E. Basaran S. Paydas
                                                                                           Journal of Supportive Care in Cancer
as well as more comparisons with           S. Sarpel T. Efficacy of pneumatic
                                                                                           17(7):1033-1034.
alternative treatments, is needed          compression and low-level laser therapy
before the benefits of LLLT for            in the treatment of postmastectomy              Drs. Basford and Cheville are with the
                                           lymphoedema: a randomized controlled            Department of Physical Medicine and
lymphedema can be accepted
                                           trial. Clinical Rehabilitation. 23(2):117-24,
comfortably as established. Further,                                                       Rehabilitation–Mayo Clinic
                                           2009 Feb.
how or whether LLLT should be                                                              200 Second Street SW
integrated in conventional complex         Kaviani A, Fateh M, Yousefi Nooraie R,          Rochester, MN 55902




 National Lymphedema Network, Inc. • 1611 Telegraph Avenue • Suite 1111 • Oakland, California 94612-2138m
 Infoline: 1-800-541-3259 • Tel: 510-208-3200 • Fax: 510-208-3110 • Email: nln@lymphnet.org • Website: www.lymphnet.orgm

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