Martin Junggebauer, Coordinator of International Business Development, WeberMedical, Germany elucidates on the uses and benefits of laser therapy and its far-reaching impact
Lasers have been important diagnostic and therapeutic tools in medicine for many years now – especially for surgical indications and interventions – the field of low-level-laser therapy is becoming increasingly recognised in medical research and about to revolutionise 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.
Nowadays, technological innovations from German company WeberMedical also facilitate various kinds of internal applications: through a special catheter technology, low level laser light can be applied either intravenously or interstitially/ intra- articular.
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 focussed laser beam penetrates the skin and delivers the energy to the acupuncture points.
Technically, the end-piece of an optical fibre that is connected to a laser diode is attached to the surface of the skin with a self adherent tube in a 90o angle. The light generated by the diode is transported through the optical fibre (at virtually no loss of energy) to the body.
For acupuncture treatments, infrared and red are the most important colours as they can penetrate the body deeper than other colours. 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 three cm and infrared light – which can even penetrate bones – only in a depth of approximately six 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 colours 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
- Immune modulation
- Regeneration on the celluar level
Effects on the cellular level include:
- Stimulation of mitochondria metabolism
- Increase of ATP production
- Stabilisation of cell membrane
Interstitial/ intra-articular laser therapy
The so-called percutaneous interstitial/ intra-articular laser therapy allows applying laser light directly in the body and thereby overcomes the ‘skin barrier’ which absorbs large amounts of the emitted photons. The technology is particularly important because blue and green light – which is normally absorbed by the surface of the skin – delivers different effects than red and infrared light to the body.
Thereby, a sterile catheter is the key technical component that facilitates the treatment. It is attached to an interstitial needle that has been inserted to the body on one end and to the light fibre at the other end. The light then makes its way through from the laser diode through the catheter and interstitial needle in the body.
Indications for interstitial laser therapies are (e.g.):
- Chronic spine syndromes
- Slipped discs
- Scar pain after surgery
- Spinal stenoses
- Neural lesions
- Deep tendinitis and strains
Indications for intra-articular laser therapies are (e.g.):
- Knee osteoarthritis
- Hip osteoarthritis
- Chronic shoulder syndromes
- Ankle joint osteoarthritis
Typically, red, green and blue light is used in interstitial/ intra-articular therapies. The different wavelengths deliver the following effects to the tissue:
- Increase of cell activity and microcirculation
- Regeneration of damaged tissue structures
- Anti-inflammatory effects
- Effective in treatment of pain connected to inflammations and swellings
- Strong anti-inflammatory effects
- Effective in wound-healing
- Immediate reduction of acute pain
Both therapies can furthermore be applied in combination with and to enhance the effects of hyaluronan injections or platelet rich plasma injections.
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 photosensitiser binds with high specificity to tumour cells anywhere in the body. The process takes several hours and tumour cells will have become light sensitive at its end. Tumour 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 tumour destruction could only be achieved at the surface of the skin or within only a few centimetre in the depth of the tissue. An effective treatment of deep tumours 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 tumours. 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 fibre optic laser catheters and direct laser activation as the other component was established as a new treatment regime for various types of cancer.
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 tumour cells: Through intravenous blood irradiation circulating tumour cells and tumour 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 immunisation 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 chemo therapy, not as an alternative therapy. It can for example contribute to lessen the side- effects of chemo therapies. 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.