Background and Objective: Laser vaporization of the prostate is considered to be a promising treatment for benign prostatic hyperplasia (BPH), and efficiency of vaporization and hemostasis are both important parameters for such treatment. In this study, we used a high-power laser diode with a wavelength of 980 nm to obtain high vaporization efficiency with good hemostasis. The objective of this study is to evaluate the efficacy of laser vaporization for treatment of BPH in ex vivo experiments using a 300-W high-power laser diode with a wavelength of 980 nm quantitatively. Materials and Methods: An ex vivo experimental setup simulating clinical treatment situation was constructed. Bovine prostate tissue was used as a sample. The power setting was 100, 150, 200, 250, or 300 W, and the irradiation time was 0.5, 1, or 2 s. After laser irradiation, vaporized and coagulated depths were measured. Results: The vaporized depth increased with the laser power and irradiation time, and the results confirmed that the high-power laser diode could efficiently vaporize the prostate tissue. Coagulated depth increased as the laser power became higher. Conclusions: Laser vaporization of prostate tissue using a high-power laser diode with a wavelength of 980 nm represents a promising treatment for BPH; this method exhibits high vaporization efficiency and good hemostasis. However, operators must be aware of the risk of postoperative perforation of the prostatic capsule caused by coagulation of deep regions that cannot be visualized by endoscopic observation.
Purpose: This « in-vitro » study had two specific aims: the first, to test using a universal testing machine whether sub-ablative Er:YAG laser irradiation prior to acid etching is effective in orthodonti cbracket bonding and secondly using micro-hardness measurements and Scanning Electron Microscopy (SEM) observations to investigate the effectiveness of de-mineralization reduction in enamel treated with sub-ablative Er:YAG laser irradiation followed by fluoride varnish application. Materials and Methods: One hundred and eighty bovine permanent maxillary incisors were selected for shear bond strength testing and microhardness measurements. Sub-ablative Er:YAG laser irradiation was set at a power density of 2.5 J/cm², a frequency of 7 Hz and air/water spray. Brackets were bonded with an auto-curing resin paste. The shear bond strength was measured comparing laser irradiated and non-irradiated enamel surface, followed by SEM observation of the bracket-resin-enamel interface. Microhardness measurements were made on enamel samples before treatment, after samples preparation, and after demineralization. Results: While the adhesion of orthodontic brackets to bovine enamel after sub-ablative Er:YAG laser irradiation and acid etching is comparable to that obtained after conventional acid etching, the effect of laser irradiation associated with topical application of fluoride varnish increases the microhardness of enamel. Conclusion: Sub-ablative Er:YAG laser irradiation before the acid etching doesn’t reduce the shear bond whereas when associated with fluoride application it may play a role in caries prevention. Further studies will be necessary to establish the mechanism by which the protective laser activated fluoride effect is achieved.
The assessment of the efficacy of low level laser therapy (LLLT) for pain attenuation varies among institutions, all having their own method of assessment with no common standards. At the author’s institution in the beginning, the patients were asked how they assessed their pain relief immediately after the treatment. They were to choose from excellent, good, fair, no change and poor. The overall efficacy rate was calculated by the numbers of patients scoring excellent and good, expressed as a percentage of the total number of patients. However, a large number of institutions have utilized the Visual Analogue Scale (VAS) or the Pain Relief Score (PRS) for the assessment of treatment; but even then, the evaluation could not be considered uniform. Therefore, the standardization of the efficacy rate was continuously discussed among the practitioners of LLLT, dating back to the 9th annual meeting of the Japan Laser Therapy Association (JaLTA) in 1997. It took four years (including the 1997 meeting) until finally an agreement was reached and a new standard of efficacy was presented at the 12th JaLTA meeting in 2000, based on the PRS. The new standard defined excellent as pain reduction in any treatment session from 10 to 0 or 1, good as reduction from 10 to 2~5, fair as reduction from 10 to 6~8, no change as a reduction from 10 to 9~10 and poor was defined as exacerbation of pain from 10 to 11 or greater. Efficacy rate was calculated by the number of patients scoring excellent and good expressed as a percentage of the total number of patients. For the purpose of reference, the VAS was to be used for patients receiving the treatment for the first time.
Background and aims: Rheumatoid arthritis (RA) is an auto-immune disease afflicting multiple joints of the body, where as a result of the increase in inflammatory cytokines and tissue destructive factors such as matrix metalloproteinase (MMP)-3, deterioration of the bones and cartilages of the joints occurs. The present investigation was carried out to study the anti-inflammatory activities of light emitting diode (LED) irradiation on hind paw inflammation in collagen-induced arthritis (CIA) mice models. Materials and method: RA in the CIA mouse model was induced by immunization of DBA/1J mice with intradermal injections of an emulsion of bovine type II collagen and complete Freund’s adjuvant. A total of 20 CIA mice were subdivided into the following groups: control group, CIA group and 2 groups of LED irradiated CIA mice (LED groups) (n=5 per group). The mouse knee joint area in the LED groups (the 570 nm and 940 nm groups) was irradiated with LED energy, three times a week for 500 s per session over 8 weeks at a dose of 5 J/cm². The hind paw swelling was assessed by the increase in hind paw thickness. The serum levels of the inflammatory cytokines and arthritic factor MMP-3 were determined with an enzyme-linked immunosorbentassay (ELISA). Results: In the LED-570 and LED-940 groups at 4weeks after arthritis induction, the swelling inhibition index was 18.1±4.9 and 29.3±4.0 respectively. Interleukin (IL)-1β, IL-6 and MMP-3 serum levels were significantly lower in the LED-940 group. Conclusions: LED irradiation, particularly in the near-infrared was effective for inhibition of the inflammatory reactions caused by RA.
Background and aims: In Japan the rise in the average life expectancy has caused an increase in the proportion of the population who are classed as geriatric. Accordingly, the number of elderly people being treated for cancer is increasing concomitantly. However, with the increase in age, the numbers of prior complications also increase. This is especially so in the advanced-aged patients, defined in Japan as those over the age of 85. Such complications may be too high risk for radical surgery and a less invasive treatment is warranted. Photodynamic therapy (PDT) is a noninvasive treatment approved by the Japanese National Health Insurance for the treatment of early stage superficial type esophageal and gastric cancers, early stage uterine cervical cancers and dysplasia, and early and advanced lung cancer. We report herein on the efficacy of palliative PDT using talaporfin sodium (Laserphyrin®) for a case of inoperable gastric cancer. Material and methods: The patient was an 87-year-old-man, a diabetic with histories of diabetic nephropathy, cerebral infarction and myocardial infarction. This patient was first diagnosed as having gastric cancer in 2007 but surgery and chemotherapy were contraindicated due to his poor physical status and poor renal function, respectively, owing to the anticipated side effects. The patient was referred to our institution after hearing of PDT in 2009. He was treated with 1 course of porfimer sodium PDT and 3 courses of talaporfin sodium PDT with photodynamic diagnosis (PDD) during the period from September, 2009 to June, 2011. Results: The massive gastric cancer located in the cardia was successfully treated with 4 PDT sessions without any serious complications; therefore the patient was able to orally ingest food until his death due to natural causes other than the cancer, in October, 2011. Conclusion: Talaporfin sodium PDT is safe and effective treatment for advanced-aged patients suffering from inoperable gastric cancer.
Background and Aims: Lichen pilaris is a very common disease typically seen among young adults on their upper arms as a manifestation of hyperkeratotic lesions occurring in the pores. Only a few treatments have been reported as significantly effective, so often natural resolution over time is the only option. The present study examined the use of a 1064 nm Q-switched Nd:YAG laser (QSNY) in quasi long-pulsed mode, in an attempt to treat a case of lichen pilaris. Subject and Methods: A 33-year-old male presented with light-brown aggregated papules observed on both sides of the upper arms. The affected areas were treated every other week (QSNY, pulse width 300 μs, pulse energy 3.0 J/cm², spot size 6 mm and repetition rate 10 Hz). Clinical photography was taken of the lesions at baseline and three months after the final treatment in addition to macrophotography and 3-D photography, biopsies being taken at both time points for histological comparison. Results: The clinical photography and objective image evaluation demonstrated shrinkage of pores and improvement of the unevenness of the skin. Histological examination suggested that the effect of the micropulsed QSNY on the horny layer, epidermal keratinocytes and dermal collagen resulted in a peeling effect and increased dermal collagen density, which eventually led to the shrinkage of the pores and improvement of the skin condition. Conclusions: The results of this single patient case report suggest that the micropulsed QSNY could be an effective treatment option for lichen pilaris, improvement of which is often difficult. Further studies with an appropriately-sized population are merited to confirm these preliminary results.