Endoscopic Submucosal Dissection (ESD) is increasingly accepted as a minimally invasive treatment for the patients with early gastrointestinal cancers. However, ESD demands high maneuverability technique, and the success of the operation is dependent of each operator’s skill. We have developed a novel laser endoscopic system for ESD to overcome such difficulties of ESD. Compared to conventional ESD using electric surgical knives, ESD using CO₂ laser method has an advantage of less risk of perforation and massive thermal damage, because the CO₂ laser is strongly absorbed by water. Farther more, due to non-contact laser irradiation and adequate visualization of treatment area, the laser system may provide more precise and safer treatment for every endoscopist.

Holmium laser (2,100 nm in wave length) enucleation of the prostate (HoLEP) which does represent the technical development in the treatment of BPH, have been popular as endoscopic surgery alternative to traditional transurethral resection of the prostate (TURP). This technique appear to be effective with low morbidity including a reduced rate of transurethral resection syndrome and minimal perioperative bleeding, as well as having a shorter catheterization time and hospital stay. We evaluated clinical results of HoLEP using the 78 W (pulse duration: 250 μs) and the 100 W (pulse duration: 600 μs) energy device.

Recently, many studies have reported that low reactive level laser therapy (LLLT) or light emitting diode therapy (LEDT) is effective in reducing muscle fatigue, enhancing muscle performance, and training effect. In this review, the author will discuss the effectiveness of LLLT/LEDT in several conditions that can induce muscle fatigue and the mechanisms underlying improvement of muscle fatigue by light therapy.

The treatment of rheumatoid arthritis (RA) has undergone dramatic changes over the past 20 years, which may be subsumed under developing medications, especially methotrexate and biologics. The goals of treating to RA have been formalized by an international task force.

RA is a chronic inflammatory disease which is characterized by pain and swelling of synovial joints. Pain is the most important determinant of the patient’s perception of RA disease activity, while it is mostly the joint swelling for the physician. An international task force emphasizes the importance of shared decision-making with the patients. It is important for medical staffs to identify the discrepancy between the patient’s and the physician’s assessment.

History of changing LLLT in the era of developing medication to RA is showed. Pain relieving effects of LLLT is increasing by using unti-TNF treatments.

The combination treatments of LLLT and medication may be better than the single treatment to aged RA patients.

Forty-one patients with sports injury were treated Low reactive Level Laser Therapy (LLLT) with diode laser. Efficacy of LLLT was evaluated with Pain relief score (PRS). Efficacy ratio of LLLT was 65.9%, and the diseases in which the effective rate was high were jumper’s knee 75%, humeral lateral epicondylitis 66.6%, Achilles tendonitis 66.6%. LLLT is useful tool for pain control in sports injury because it is minimally invasive and safe therapy for athlete.

The mechanism of bactericidal effect of photodynamic therapy (PDT) is considered that photoactivated photosensitizer (PS) accumulated in bacteria generates reactive oxygen species (ROS), and the ROS induce irreversible cell damage to organisms. However, recent investigations have shown that PDT induces other phenomena that support antimicrobial effect, including an activation of host immune cells to phagocyte microorganisms and increase in expressions of growth factors for cellular proliferation. Hence in this short review, we discuss the PDT effects on wound healing, while introducing our recent studies using 5-aminolevuric acid plus light irradiation.

Removal of dental plaque and/or carious dentine has been conventionally performed by mechanical instrumentations. In recent years, an application of antimicrobial photodynamic therapy (a-PDT) using diode laser or LED lights together with dye as photosensitizer has been proposed and studied to use dental treatments. In this communication, an application of a-PDT, for the treatments of dental caries and periodontal diseases which are two major oral diseases, is discussed based on the current basic and clinical studies. We also introduce current our studies focused on the application of a-PDT in periodontal treatments.

Recently, bacteria resistant to many antibiotics have spread and become a problem. Because using antibiotic causes to produce antibiotic-resistant bacteria, it is thought that it is necessary to develop new mean which is different from antibiotic, in order not to increase the number of resistant bacteria anymore. We focus on and study photodynamic therapy (PDT) as new treatment of bacteria infections. Here, we report effect of PDT against infection ulcer we have done so far.

In the veterinary field, canine otitis is one most common infectious disease. However, it occur a problem that inproper usage of antibiotics induces resistant bacteria. In the present paper, as a novel therapy against infectious otitis, we describe fundamental studies of photodynamic antimicrobial chemotherapy (antibiotic PDT) and its clinical application using existing dye and novel chlorine derivative photosensitizer.