This paper proposes a computational clinical trial of laser treatment for rapid and low cost evaluation of novel medical laser devices. The optical propagation and photothermal damage process after pulse laser irradiation are modeled and the safety of the laser treatment with the evaluation target devices is evaluated by numerical simulation. The computational clinical trial result shows the safety of a novel nanosecond laser device for skin treatment is equivalent to the device that has been approved for clinical use.

The immediate effects of pulse irradiation with a 10-W semiconductor laser on current perception threshold and current pain threshold were examined. As a result, the minimum perceptual current value reflecting the current perception threshold did not change, but the minimum pain current value reflecting the current pain threshold showed a significant increase after laser irradiation in the irradiation group. However, there was no significant change in the minimum perceived current value and minimum pain current value in the control group. Hence, it was suggested that laser irradiation increased the pain threshold.

To obtain a fingerprint pattern without being affected by protrusions and indentations on the skin surface is important for fingerprint identification. In our previous work, we discovered a fine structure corresponding to the fingerprint pattern in the stratum corneum and surrounding area from observation of OCT images, and developed a method which detects the light from the light source goes through a fine structure and create grayscale images corresponding to a fingerprint pattern. In this paper, to clarify the origins of the greyscale image, we propose a simple simulated model of the fine structure of different light scattering properties alternately arranged in the epidermis of finger skin. We calculated the light intensity distribution via a Monte Carlo simulation of light scattering with two parameter sets at 640 nm. We found that the light passing through this model created a greyscale image that corresponded to the epidermis structure.

We conducted a drug use-results survey of Penles^® Tape 18 mg, a patch formulation containing lidocaine 18 mg, for pain relief in skin laser treatment and collected case report forms of 304 cases. Five adverse drug reactions occurred in four patients (1.43%) of 280 patients in the safety population, all of which were non-serious. The effectiveness measured by the pain level at the time of laser irradiation to the skin evaluated by physicians was 80.6% (241/299 cases). The above results confirmed the safety and effectiveness of Penles^® Tape 18 mg for pain relief in skin laser treatment.

We developed a multi-layered optical phantom which models a layered structure of human skin tissue. Spectral reflectance similar to that of human skin was realized in the visible wavelength range by optimizing volume concentrations of absorber, scatterer, and base material in each of nine layers. We also investigated reproducibility and temporal deterioration property of fabricated phantoms. Finally, we tried to make a pigmented purpura-like phantom as an example of applications and confirmed its color characteristics.

Efficient algorithm of Monte-Carlo simulation of scattered light which re-emerges from the incident point of light and has a specific pathlength is reviewed. Calculation procedures of this algorithm for uniform and nonuniform scattering media are explained and examples of simulation results are shown. This algorithm can efficiently analyze scattered light detected by optical coherence tomography.

The authors have been studying the photoacoustic imaging from its basic to clinical applications. As a part of the wide-ranged studies, the numerical simulations of the photoacoustic pressure wave have been carried out for the image reconstruction of the concentration of the photon absorber and for the evaluation of gold nanoparticle as a contrast agent. The numerical simulation can be applied to planning safe and effective treatments using photoacoustic effect in dermatology. This article reviews the numerical simulations and the applications of them.

Diffuse optical spectroscopy provides functional and morphological information of living tissues based on optical absorption and scattering properties. Diffuse reflectance spectroscopy (DRS) can be achieved with simple and low cost equipment, and has been widely applied to in vivo measurements and imaging of biological tissues. In the present article, in vivo evaluation of hemodynamics and changes in tissue morphology by using DRS based on the Monte Carlo simulation for light transport in biological tissues and its application to biomedical imaging are described.

Since 2004, our hospital has performed photofrin photodynamic therapy (PDT) on 81 patients with cervical intraepithelial neoplasia 3 of the uterine cervix. No patients displayed recurrence after photofrin PDT. Of these patients, 27 became pregnant, with a total gravidity of 46. This study retrospectively reports the perinatal prognosis of pregnancy in 21 patients following photofrin PDT and compares it to that in 17 patients following cervix conization who delivered at our hospital. Following cervix conization in primipara, premature labor rate and emergency caesarean section rate increased, and following cervix conization in multipara, the gestational age at birth decreased. Conversely, following photofrin PDT in primipara, the premature labor rate was low, but bleeding during childbirth increased. No significant difference was identified in the partograph; therefore we compared the partograph with Friedman’s curve. Furthermore, following photofrin PDT, the premonitory stage of labor was prolonged, but the first stage of labor was not prolonged. Conversely, following cervix conization, the duration of labor decreased with Friedman’s curve. In our hospital, pregnancies following photofrin PDT were generally favorable, without premature delivery. Additionally, the emergency cesarean section rate was low for deliveries following photofrin PDT. However, care is necessary because there is an increase in bleeding during childbirth following photofrin PDT. We aim to have a safe perinatal prognosis following photofrin PDT to ensure its continuity in future.

Cervical intraepithelial neoplasia is a premalignancy of cervical cancer, and is not a rare disease. Standard treatment for cervical intraepithelial neoplasia (CIN) 3 is surgery, but this method has been shown to lead to premature birth. Photodynamic therapy (PDT) is a minimally invasive treatment option for carcinoma in situ (CIS). Several authors have reported the efficacy of conventional PDT, but the diffusion rate continues to be set low, due to concerns regarding side effects and the need for prolonged hospitalization. We have conducted an innovative clinical trial for patients with CIN using 5-Aminolevulinic acid (5ALA) and LED technology.

[Purpose] Cervical intraepithelial neoplasia (CIN) and early cervical cancer are frequently detected in women of reproductive age. The appropriate treatments for these diseases should be selected considering sparing fertility. Of these treatments, photodynamic therapy (PDT) is a minimally invasive therapeutic technique that enables sparing of the cervix and is as effective as cervical conization in terms of treatment results. Talaporfin sodium (NPe6)-mediated PDT was administered intravenously to nine CIN cases. This study aimed to evaluate the effect of PDT and photosensitivity in these cases.

[Methods] PDT was administered to nine patients who were diagnosed with CIN based on cervical cytology, histology, and colposcopy findings. NPe6 was administered intravenously at a dose of 40 mg/m². Four hours after the administration of NPe6, the patients were exposed to photoradiation (100 J/cm²).

[Results] PDT was used to treat a total of nine patients (two patients with CIN2 and seven patients with CIN3). Cure was confirmed in eight cases who were available for follow up thorough examinations conducted at three and six months after photoradiation. Seven patients exhibited no photosensitivity at day 14 after NPe6 administration. Mild photosensitivity by direct sunlight test was observed in one patient up to day 28.

[Conclusion] This study suggests that NPe6-mediated PDT might be a promising treatment for CIN.

Ultrasonic testing and cytodiagnosis have been used for the diagnosis of endometrial disease. However, lesions can not be observed under direct view with these techniques. Laser therapy facilitates observation and treatment of the uterine body. The images produced by the minimally invasive laser therapy system are of high quality, and it is easier to irradiate a laser beam on target lesions. This technology may provide a new treatment strategy of early endometrial cancer.

For the purpose of development of the laser technique in veterinary medicine, the new bowel welding method using a diode laser were devised. A special intestinal clamp was developed for these studies, and it was named laser welding intestinal clamp (LW clamp). In fundamental researches, laser welding of bowel in dogs and cats was confirmed to be possible using the LW clamp and the contact probes under a diode laser. Therefore, we expected that this method is applicable to clinical cases. Laser bowel anastomoses were performed for cats with megacolon and toy-breed dogs with severe bowel obstruction. As short- and long-term clinical results, any severe postoperative complications were not found, and all cases revealed favorable recovery.

Surgical therapy, chemotherapy and radiotherapy are the main treatments for cancer treatment in the veterinary medicine. Treatment using immunity has attracted attention as the fourth treatment. However, immunotherapy for tumor in veterinary field is not put to practical use as a standard therapy yet. Except for immunotherapy, hyperthermia, cryotherapy, and photodynamic therapy are also being carried out for canine cancer treatment, but these therapies are not spread out because of insufficient evidence, and high cost of instrument and drug. In this study, we will introduce two canine cases in which the mammary gland tumor has shrunk by conducting combination ablation using semiconductor laser and interferon γ against tumor.

It was reported that tumor specific immunity is induced by local administration of hemagglutinating virus of Japan envelope (HVJ-E) to malignant tumor tissue. In the present case report, we tried to activate tumor specific immunity in feline mammary adenocarcinoma by NPe6 HVJ-E PDT where photodynamic therapy (PDT) was performed after local administration of HVJ-E containing taraporfin sodium (NPe6) into the tumor tissue. As a result of the treatment, necrosis of tumor cells and infiltration of macrophages in tumor tissue which were induced by NPe6 HVJ-E PDT were confirmed in and around the tumor. In addition, lymphocyte infiltration was remarkably observed around the tumor as compared with untreated tumor, and the immunity induction effect of NPe6 HVJ-E PDT was confirmed.

We synthesized liposomally formulated phospholipid-conjugated indocyanine green (ICG-lipo) in 2010. Using the ICG-lipo and diode laser, we tried to treat in 38 cases of animal spontaneous tumors. Irradiation was performed for 10–20 min and its intervals were every day or 3 times per week after injection of the ICG-lipo. Due to Response Evaluation Criteria in Solid Tumors (RECIST), outcome of response rate of 38 cases was as follows; CR (Complete response): 3 cases, PR (Partial response): 13 cases, SD (Stable disease): 18 cases, PD (Progressive disease): 4 cases. Response and Efficacy rates were 42.1% and 89.5%, respectively. In particular, Response rate of lymphoma was 85.7%. In the tumors which have more than two cases, efficacy rate was 100.0% except for lymphoma and hemangiosarcoma. Out of veterinarians who performed this therapy, about half of them recognaized improvement of general condition of patients. This evidence suggests efficiency of this therapy as a cancer therapy.