Contra-indications of Therapeutic Laser Treatment

L. Navratil, M. D. J. Kymplova, M. D. Institute of Biophysics, 1st Medical Faculty of the Charles´ University, Prague, CZ leos.navratil@lf1.cuni.cz, jaroslava.kymplova@lf1.cuni.cz

Many contra-indications of non-invasive laser therapy are still surviving in literature. However, some of them are just being mentioned quite uselessly, their justification having never been acknowledged, and their persistant mentioning being based on quoting from one publication to another without authors having examined their validity. Thus numerous useless errors can always appear, and many therapists, whose practical training may have not been primarily aimed at initial use of therapy lasers in medicine, do not only avoid indication of this kind of therapy, but, moreover, they sometimes even discourage their patients despite of the fact that application of therapeutic laser would be a benefit for them in their particular complaint. Contra-indications stated so far can be divided in three main groups: - indications not suitable for laser therapy in general - indications not suitable for laser therapy in some cases - indications stated by mistake as not suitable for laser therapy Indications Not Suitable for Laser Therapy in General It is beyond dispute that laser therapy is contra-indicated on malignant diseases with regard to experimentally proven biostimulative effect, which is brought about by activization of enzymes of respiratory chain (flavin dehydrogenasis, cytochromeoxidasis) with anti-oxidation effect being strengthened simultaneously. The process of tissue oxidation is a chain of reactions, during which electrones in mitochondrias are transferred by a system of carriers from a suitable substrate up to oxygen. Transfer of hydrogen to flavoprotein is connected with production of ATP and ADP, and further transfer through flavoproteinocytochrome system gives life to two more molecules of ATP in each pair of transferred protons. Such a linkage of ATP formation to oxidation is called aerobic phosphorylation. The process is dependent on sufficient supply of ADP and therefore it is under control of a certain kind of a feedback: the quicker the utilization of ATP in tissue, the quicker the production of ADP can be followed and thus the quicker the aerobic phosphorylation there is. This increases concentration of adesinphosphate adesindiphosphate, and adesinmonophosphate in cells after irradiation with therapeutic laser, as described by Romanov et al. Increased amount of energy stimulates quicker replication of mitochondrial DNA in the course of the G0 - S phasis. Locally increased consumptions of oxygen and glucoses prove metabolism in irradiated tissue. Irradiation in the area of neck of patients suffering from hyperthyroidism cannot be recommended, too, due to biostimulation effect. Even though no scientific work describing the influence of therapeutic laser on activity of thyroid gland has been known to us, above mentioned actions can obviously cause this state and therefore it is necessary to carry out applications on this particular area with maximum care. Epilepsy can also be regarded to by some authors as to a significant contra-indication of non- invasive laser therapy. Although the cause of a possible induction of an attack has not been quite clear so far, it is expected that possible cause can be induced by a certain frequency modulation of laser beam.

Direct irradiation of eye retina is a generally accepted contra-indication. Applications of therapeutic laser shall also avoid irradiation of belly of pregnant women, as well as intravaginal applications on them, in spite of Cheeteman and his colleagues having noticed no teratogenous changes on chicken embryae even after irradiations with significantly higher energy density than usually applied. Before we start treatment with a therapeutic laser it is also necessary to confirm that no medication, massage liquid, nor cosmetics, containing a photosensibilitative matter, has been taken by the patient or used on him/her. Should this be the case, there could be a danger of a massive injure of the tissue containing this matter by energy of photons. Indications Not Suitable for Laser Therapy in Some Cases Some authors consider the use of therapeutic lasers contra-indicated for feverish disorders and infectious diseases. It is always necessary to judge the particular state of health and etiology of a disease. Discrepancies in data evaluating the effect of therapeutic laser on activity of bacteria and/or viruses should be stressed. Some scientific works point at direct sensitivity of some microorganisms on therapeutic laser. Such sensitivity can be utilized especially in dentistry as it can be seen on decreased vitality of microflora after irradiation of mucosis in mouth (bacteriostatic effect of laser). G+ bacterias are especially sensitive. This presumption has been proven even in laboratory conditions, where upon irradiation of the cultivation plate with energy density of 2 Joules per disc, decreased growth of almost all common varieties of pathogenic bacteria could be noticed. On the other hand, some papers describe a positive biostimulation effect of laser on growth of bacteria. For example, highest stimulation of growth with energy density 337.0 mJ/cm2 has been reported with a GaAs laser, however other papers do not mention growth stimulation of bacteria with a therapeutic density of energy. Also here a dependency of biostimulation effect of laser irradiation on wavelength of laser can be seen, where, on one hand, rays of Ruby and Neodymium lasers do not stimulate growth of grammpositive bacteria, whilst on the other hand Ruby laser increases production of pigment in Pseudomonas Aeruginosa. Studies from the Medical Faculty of Palacky´s University in Olomouc, CZ, have followed dependency of length of laser expozition on growth of microbes, both on blood agar on cultivation plate and in broth. Tribes of Staphylococcus Aureus, Streptococcus b Haemolyticus, Streptococcus Pneumoniae and Neisseria Catarrhalis were used for the experiment. With these tribes being applied on agar soil in quantity of 104 microbes /1 ml, no macroscopically visible changes could be noticed in comparison with the control group after irradiation of the plate by a He-Ne laser with energy density of 0.3, 0.6, 1.5, 3.0 and 6.0 J/cm2 . In the second case the tribes were irradiated in broth twice in 2 hours interval, each with the energy of 6 J per 5 ml of broth. In all used bacterial tribes higher activity of irradiated cultures in comparison with control groups could be registered. However, more significant activity, in higher orders, has only been registered with Staphyllococcae. Thus these results would rather confirm the fact that no direct antibacterial effect does contribute to the processes of healing. Positive effect of laser irradiation in purulent wounds and trophic ulcers can therefore be caused by improvement of local immunity of irradiated tissue, by activation of phagocytosis and proteolytic ferments, as well as by increased blood flow. These studies clearly identify necessity of individual access with no useless apprehension towards each patient with above mentioned complaints. The authors can see no particular reason for avoiding non-invasive laser therapy if the source of infection is not directly irradiated. Application of laser will speed up initial healing of such an open wound (ulcus cruris, bed sores etc.).

Neither it is possible to mention blood diseases as contra-indications of therapeutic laser. The issue is just too broad, for with a little hyperbole, a slight hypochromatic anemia as well as a myeloblastic leucaemia, imminently endangering life, can both be considered blood diseases. Whilst for the use of therapeutic laser on patients suffering from malignant haematological disorders the rules mentioned above in this work must be observed, it is unnecessary to avoid this kind of treatment in case of anemia, caused by iron insufficiency as a result of one-sided food. Several years of our experience have clearly proven that initial laser therapy has no influence on lifetime of blood cells and we can see no reason why to avoid application of laser in any area with the exception of irradiation of localities with blood-productive marrow. Due care is necessary when using therapeutic laser on patients with a higher blood loss, with regard to vasodilatation effect of laser therapy. Analgesic effect of non-invasive laser therapy is brought, among others, by decreased sensitivity of peripheral neural terminations. That is why maximum care should be taken in the course of applications of therapeutic laser in areas with lower sensitivity, where a combination of these two phenomena can disqualify local natural protective mechanism of the body and increased jeopardy of damage in affected area, for example by sunshine, can be a real threat. Indications Stated by Mistake as Not Suitable for Laser Therapy Other contra-indications mentioned in literature from time to time can be considered, from the point of view of contemporary level of knowledge on laser therapy, useless and confusing for doctors. Here we have in mind especially the use of therapeutic laser on patients with a pacemaker. Should this contra-indication be right, it would also mean contra-indication of x-ray examination or of direct exposure to sunlight on skin for these people. As far as we know, this contra-indication came to literature by mistake, and through references to and by various authors this error is still preserved. Application of therapeutic laser in the area of gonads one does not have to be afraid of, it is only necessary to keep to recommended amounts of energy. With lower power density (up to 1.3 J/cm2) laser has a stimulative effect on male germina cells, however with several times multiplied energy density a possibility of mutation cannot be fully cut out. No negative effect of non-invasive laser therapy has been reported on women, even when applied intravaginally. Further questionable contra-indications are states of exhaustion or decrepitude, or dependency on alcohol and/or drugs, frequently given in literature. These contra-indications cannot be considered logical. On the contrary, local applications of therapeutic laser in some indications mean significant contribution for patients, and such a therapy is, with regard to its minimal side-effects, definitely more considerate for them in comparison with any other kind of treatment (for example with medication). Works of English authors have proven that apprehensions of possible damage to epiphyseal fissures in case of application of laser therapy in this area are useless. In the light of works of the authors from Motol we can brand useless gratuitous apprehensions of application of therapeutic laser on patients with worse express or seize abilities resulting from damage of cerebral tissue. However, it is necessary to stress that in this case laser should be in hands of well experienced specialist. Conclusions:

The authors of this work are well aware of the fact that the cogent issue has only been denoted here. However, the extent of the paper cannot be widened with regard to technical capacities of the publisher, and therefore they refer to further professional literature by theirs, or by other authors.