The exploitation of photobiology in medicine has been of great interest to mankind. There is a growing interest in the use of lasers for treatment purposes because of the photochemical alterations induced in biomolecules by light energy. In this paper we present our data on laser biostimulation, the combination of pharmacological treatments Solcoseryl™ (SS) and Polygen™ (PG) with light therapy using in-vitro and in-vivo models. In-vitro experiments indicate the ability of laser photons and pharmacological agents SS or PG to augment or abate the cloning efficiency of various cell lines. In-vivo studies focused on the dosimetry of various laser wavelengths and the use of wound healing drugs and 632.8nm laser in wound healing. The application of pharmacological treatments combined with laser therapy reveals the utility of light-drug treatment combinations. Given the ever-increasing cost of medical care, the burden incurred on patients, caregivers and society, this line of research fulfills the increasing need to develop treatment methods that enhance wound healing, especially in situations involving resistance to healing.
We investigated the characteristics of low-reactive-level laser therapy (LLLT) and analyzed the effects thermographically in patients with cerebral palsy. We determined transmissivity in exposed bone specimens and in the human body using a camera with a wavelength-specific charge-coupled device. The effects of LLLT were dispersed throughout the entire body, and transmitted through bone tissue as well. At an output level of 100 mW, the laser reached a depth of about 2 cm. To study the effects on the autonomic nervous system, we treated 50 patients with cerebral palsy using the gohkoku acupuncture point (between the bases of the first and second metacarpal bones) of the left hand, and measured changes in the skin temperature of both hands. A GaALAs-diode continuous-wave laser beam with a wavelength of 810 nm and power output of 100mW was applied for 60 seconds and the skin temperature was measured with a Thermotracor TH1106 apparatus (NEC San-ei). The results were classified into 3 categories : temperature decrease, no change, and temperature increase. For evaluation of the autonomic nervous system, the laser was applied over muscles with increased muscle tone all over the body in 12 patients with cerebral palsy. Color Doppler showed an increase in blood flow in the common carotid artery in eight of the 12 patients. High speed Fourier analysis of the R-R interval in the Holter electrocardiogram showed increases in the high-frequency components originating from the parasympathetic nerves after irradiation in the same eight patients, suggesting the involvement of the autonomic nervous system in producing this change.
Dentinal hypersensitivity has been studied for several years. It is reported as a strikingly painful condition that originates from the exposure of dentinal tubuli when the thickness of the enamel or cement is significantly reduced. Usually the exposed area is subjected to several kinds of stimuli, resulting in sharp acute pain. The aim of this study was to evaluate the efficacy of low level laser therapy (LLLT) in the treatment of patients with dentinal hypersensitivity. A total of 1102 teeth of 388 patients were treated with LLLT between 1995-2000. Ninety-eight males and 290 females aged 30 to 45 years old were treated. For LLLT, a 780nm continuous wave diode laser was used at an output of 40mW, elliptical area of the beam, 2mm2, and exposure time per point of 25s. This corresponds to an equivalent dose of 50 J/cm2 at each point (considering the area of the spot). If a 1 cm2 area is considered, the total dose per tooth was 4J/cm2. With the 830nm CW 50mW diode laser, the elliptical area of the beam was 2mm2, and exposure time per point was 20s. This corresponds to an equivalent dose of 50J/cm2 at each point (considering the area of the spot). If a 1cm2 area is considered, the total dose per tooth was 4J/cm2. The results showed 403 (36.57%) out of 1102 teeth required a single session for complete remission of the symptom, 255 (23.14%) needed two sessions; 182 (16.51 %) three sessions; 107 (9.7%) four sessions; and 59 (5.35%) five sessions. Ninety-six (8.71%) did not respond to LLLT and the patients were re-assessed and treatment changed. The more affected tooth was the lower premolar (301 - 27.4%), followed by lower molars (163 - 14.8%), upper premolar (149 - 13.5%), lower incisive (148 - 13.4%), upper canine (119 - 10.7%), upper incisive (108 - 9.9%), lower canine (62 - 5.6%), and upper molars (52 - 4.7%). The result of the present investigation demonstrates that LLLT, when used with the correct irradiation parameters, is effective in treating dentinal hypersensitivity, as it quickly reduces pain and maintains a prolonged pain-free status in 91.27% of the cases. Previous studies carried out by the authors examined the histological reaction of the dentinal pulp in rats after application of LLLT. The LLLT was shown to be effective in stimulating odontoblasts, producing repaired dentine and closing dentine tubuli.
Connective tissue injuries, such as tendon rupture and ligamentous strains, are common. Unlike most soft tissues that require 7-10 days to heal, primary healing of tendons and other dense connective tissues take as much as 6 - 8 weeks during which they are inevitably protected in immobilization casts to avoid re-injury. Such long periods of immobilization impair functional rehabilitation and predispose a multitude of complications that could be minimized if healing is quickened and the duration of cast immobilization reduced. In separate studies, we tested the hypothesis that early function, ultrasound, 632.8 nm He-Ne laser, and 904 nm Ga-As laser, when used singly or in combination, promote healing of experimentally severed and repaired rabbit Achilles tendons as evidenced by biochemical, biomechanical, and morphological indices of healing. Our results demonstrate that: (1) appropriate doses of each modality, i.e., early functional activities, ultrasound, He-Ne and Ga-As laser therapy augment collagen synthesis, modulate maturation of newly synthesized collagen, and overall, enhance the biomechanical characteristics of the repaired tendons. (2) Combinations of either of the two lasers with early function and either ultrasound or electrical stimulation further promote collagen synthesis when compared to functional activities alone. However, the biomechanical effects measured in tendons receiving the multi-therapy were similar, i.e., not better than the earlier single modality trials. Although tissue repair processes in humans may differ from that of rabbits, these findings suggest that human cases of connective tissue injuries, e.g., Achilles tendon rupture, may benefit from appropriate doses of He-Ne laser, Ga-As laser, and other therapeutic modalities, when used singly or in combination. Our recent meta-analysis of the laser therapy literature further corroborate these findings.
Acute-phase injury is generally treated by localized cooling of the region, and rarely by the active use of low level laser therapy (LLLT) in Japan. Thermographic studies of acutephase injury revealed that circulatory disturbances at the site of trauma occurred due to swelling and edema on the day following the injury, and that skin temperature was high at the site of the trauma and low at the periphery. Following LLLT, circulatory disturbances rapidly improved, while temperature in the high temperature zone around the site of trauma fell by 3 degrees on the average, but at the periphery the low temperature rose by 3 degrees on the average to nearly normal skin temperature. Clinically, swelling and edema improved. LLLT was also useful in treating necrosis of the skin in the wound area and in accelerating healing of surgical wounds of paralytic feet, which are prone to delayed, wound healing and also wounds due to spoke injury. LLLT is useful in treating swelling and edema in acutephase injury and in accelerating healing of surgical wounds.
In the current study we compare the effect of different light sources in the visible and near infra-red (IR) range on cell stimulation. It is obvious that in order to interact with the living cell, light has to be absorbed by intracellular chromophores. In a search for chromophores responsible for photobiostimulation, endogenous porphyrins, mitochondrial and membranal cytochromes were found to be suitable candidates, as they possess absorption bands in the visible and near I.R. ranges. The above-mentioned chromophores are photosensitizers that generate reactive oxygen species (ROS) following irradiation. In our opinion the first step in photobiostimulation might be ROS formation. To confirm ROS formation by various light sources, we used the electron paramagnetic resonance (EPR) associated with spin trapping techniques. All wavelengths used (360, 630, 660, 830nm), including a broad band in the visible range (400-800nm), stimulated hydroxyl radical formation in sperm cells. Measuring the amount of OH radicals as a function of the irradiating wavelength shows that shorter wavelengths might be more effective on the cell than longer ones.
The author presents the possibilities of using low-energy laser therapy in treatment according to the most up-to-date bibliography and his own observations. Therapeutic techniques presently used are discussed as well. The author attempts to explain the terms often applied in quantum medicine. Positive therapeutic results confirmed by advanced experiments and clinical observations contribute to extending the range of treatment methods used so far.
The author presents a twenty-seven year retrospective overview of his work in laser surgery and, more specifically, laser therapy, during which over 45,000 patients have been treated at the author's clinics as of June 2001. The author traces his laser roots, starting in 1974 with his visit to the laboratory and clinic of the late Professor Leon Goldman at the University of Cincinnati to study the evolution of cutaneous laser treatment. Upon returning to Japan, the author developed and used the new laser technology first in Shizuoka and then in Tokyo. He used the laser to remove congenital and acquired pigmented nevi, hemangiaoma and other cutaneous defects, and by 1978 had treated over 3,000 patients. In the course of these treatments he noted some interesting phenomena associated specifically with laser treatment compared with conventional methodology, such as the ability to treat side effects caused by some of the conventional methods. He also noted that treatment of target lesions with laser often concomitantly treated unassociated painful symptoms such as postherpetic neuralgia, consequently in 1979 the author specifically targeted pain applications using existing and newly developed laser systems. These included the defocused beam of the Nd:YAG, the HeNe laser, and a series of diode lasers developed both at the Japan Medical Laser Laboratory and in conjunction with Matsushita Electric Company. The International Society for Laser Surgery and Medicine (ISLSM) held its fourth meeting in Tokyo in 1981, at which the first commercially-available battery-powered laser therapy system was unveiled. Since then many other systems have been developed and experimentally evaluated. In 1988, the author was one of the founding members and the first President of the International Laser Therapy Association, and was the founding Editor-in-Chief of the journal, Laser Therapy, first published by John Wiley and Sons of Chichester, UK. To date, using laser therapy alone, over 9,000 patients have been treated at the author's clinics, and a further 29,000 have been treated with laser therapy in combination with laser surgery, as part of the author's total treatment concept (TTC). Case reports are presented to illustrate the author's concepts of low reactive level laser therapy (LLLT), high reactive level laser treatment (HLLT), and his latest concept of medium reactive level laser treatment (MLLT).