Current and Future Uses for Laser Therapy

posted by Apollo Lasers on Friday, April 10, 2015

Low-level laser therapy is being used or considered in a number of applications, ranging from pain to cancer to stroke and other brain injuries. Martin Junggebauer, Coordinator of International Business Development, WeberMedical, Germany, discusses current and future uses and benefits of laser therapy and its far-reaching impact in this article from Express Healthcare. 

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Lasers have been important diagnostic and therapeutic tools in medicine for many years now – especially for surgical indications and interventions – and the field of low-level-laser therapy is becoming increasingly recognized in medical research and about to revolutionize the field of regenerative medicine.

As the name suggests, low-level lasers run on comparably low power: Only lasers up to 500mW are considered low-level lasers. Practically, most lasers in low-level laser therapy run on even lower power, mainly between 5mW and 100mW, depending on the indication.

The range of already well-known indications includes the stimulation of acupuncture points as highly focused red and infrared laser light is able to penetrate deeply into the body and thus functions as a pain-free alternative to metal needles. Applications in dermatology are also well-established since many years.

Laser light acupuncture

Laser light acupuncture means a non-invasive and pain free stimulation of acupuncture points without needles actually penetrating the skin – only the highly focused laser beam penetrates the skin and delivers the energy to the acupuncture points.

Technically, the end-piece of an optical fiber that is connected to a laser diode is attached to the surface of the skin with a self -dherent tube in a 90o angle. The light generated by the diode is transported through the optical fiber (at virtually no loss of energy) to the body.

For acupuncture treatments, infrared and red are the most important colors as they can penetrate the body deeper than other colors. Blue light is absorbed already in a depth of 1 cm, green light in a depth of 0.5 cm, red light in a depth of 3 cm and infrared light – which can even penetrate bones – only in a depth of approximately 6 cm. Due to the limited penetration depth, green and blue light are only used for ear acupuncture. Corresponding to their penetration depths, red and infrared light can be used to stimulate acupuncture points deep in the tissue.

The key mechanism of action is the stimulation of stem cells, which are located around acupuncture points in much higher quantities than in other tissue. Besides that, different colors deliver different additional biological effects to the body.

The following box shows typical indications for laser light acupuncture:

Clinical effects include:

• Pain reduction
• Improvement of blood circulation
• Detumescence
• Immune modulation
• Regeneration on the celluar level

Effects on the cellular level include:

• Stimulation of mitochondria metabolism
• Increase of ATP production
• Stabilization of cell membrane

Intravenous laser blood irradiation

There are several mechanisms of action how intravenous blood irradiation unfolds its effect in the body. In general, laser blood irradiation leads to anti-inflammatory effects and improvements of the immunologic activity of the blood.

Photodynamic laser therapy

Photodynamic laser therapy is one of the most interesting and promising approaches in the treatment of different cancers and in dermatology. The therapy is easy to perform and goes along without severe side effects.

PDT in oncology

The principle is the stimulation of a light sensitive drug, which is injected into the blood. Through endocytosis, the so-called photosensitizer binds with high specificity to tumor cells anywhere in the body. The process takes several hours and tumor cells will have become light sensitive at its end. Tumor tissue can then be destroyed by irradiation with light of appropriate wavelength according to the absorption spectra of the various photosensitizers. The basic principle behind this mechanism is the development of radical oxygen species.

Until recently, due to the limited penetration depth of light effective photosensitizer stimulation and tumor destruction could only be achieved at the surface of the skin or within only a few centimeters in the depth of the tissue. An effective treatment of deep tumors or metastases (e.g. liver cancer or lymph nodes) was thus not possible and therapeutic applications had so far been primarily used to treat dermatological tumors. Today, the mentioned new technological developments that facilitate “systemic photodynamic therapies” and interstitial laser therapies overcome this barrier and constitute the basis for massive growth in the field.

A combination of “systemic PDT” via intravenously applied photosensitizers and subsequent intravenous irradiation as one component and interstitial PDT with fiber optic laser catheters and direct laser activation as the other component was established as a new treatment regime for various types of cancer.

Spotlight: Effects of Low-Level-Laser therapy

• Normalisation of the cell membrane potential
• Stimulation of immune response, specific and non-specific
• Increase of the immunoglobulines IgG, IgM and IgA
• Stimulation of interferons, interleukins and TNF-alpha
• Stimulation of the proliferation of lymphocytes
• Increase of phagocytic activity of macrophages
• Lowering of CRP
• Improvement of the anti-oxidant enzymatic system with antitoxic effect
• Improvement of regeneration of erythrocytes and of microcirculation
• Reduction of aggregation of thrombocytes
• Activation of fibrinolysis
• Stimulation of the NO-production in monocytes with vasodilatation and improvement of endothelial dysfunction
• Fusion of mitochondria to “giant mitochondria” with increase of ATP-production in the respiratory chain

Thereby, a good many of immune reactions go hand in hand with the primary effect of the introduced treatment regime, the destruction of tumor cells: Through intravenous blood irradiation circulating tumor cells and tumor stem cells can be destroyed and concomitant infections can be treated after a photosensitizer has been given to the body.

In addition, an oxygenation system can be employed as well to improve the micro circulation and oxygen supply. Another recommendation to support immune reactions after PDT is a immunization therapy with macrophage activating substances, e.g. GcMAF from Japan. It can be injected subcutaneously for several months after the PDT treatment.

Even though the results of PDT are very promising by itself, the therapy should be regarded as a complementary approach to traditional chemotherapy, not as an alternative therapy. It can for example contribute to lessen the side- effects of chemotherapies. Additionally, many chemo therapeutics have an absorption spectrum that allows their usage as photosensitizers.

PDT in dermatology

Furthermore, the topical (external) photodynamic therapy is also highly effective in dermatology.

Here, PDT is well established to treat various kinds of skin cancer and its pre-stages. PDT is furthermore effective in the treatment of sklerodermy, acne vulgaris, psoriasis, different kinds of hyper keratosis, virus induced vulgar warts and other chronic skin diseases. Approved drugs in this context are: 5-Aminolavulinic acid (5-ALA) and its methylester Methyl-5-amino-4-oxopentan oat (MAOP)

Transcranial laser therapy

The transcranial (infrared) laser therapy is an innovative and promising new treatment option for stroke, Parkinson’s, Alzheimer’s, migraine, vertigo, tinnitus or other cerebral disorders.

Transcranial laser application with direct irradiation of the human brain is done with highly focused infrared lasers as infrared light is able to penetrate bones and bring the light energy into the targeted brain areas. A special head adapter can be used to facilitate a stable positioning of the laser modules.

Various experiments could demonstrate that transcranial infrared laser therapy improves intra-cerebral microcirculation and reduces the area of infarction. Additionally, activation of neuronal growth after laser therapy could be observed.

The mechanism behind this approach seems to be an induction of biochemical metabolic pathways within the neurons. The light spectrum of infrared light is equivalent to the absorption spectrum of copper ions in the cytochrom-c-oxidase (terminal enzyme complex of the inner mitochondria membrane). Thus, it can be supposed that infrared laser irradiation leads to increased mitochondrial ATP production. Due to the increased energy metabolism in the penumbra and a reduced rate of apoptosis, neuro-reparative processes are achieved.