Early dye laser treatment for strawberry marks has been our first choice. Patients are classified by age of first treatment for three groups (under 1 year, between 1 and 2 years, above 2 years) and by appearances for two groups (plaque type and tumor type). The results of laser treatment in each groups was compared. In most cases the wrinkles on the surface disappeared. In cases under 1 year old the height of the mass tended to become flat though they were of the tumor type. Our cases showed no conspicuous scar formation, clearly differing from cases without dye laser treatment. Strawberry marks are common in premature babies and seven cases were treated. Flattening was observed in tumor type and good results were obtained in the majority of cases.

View full abstract

In photodynamic therapy (PDT), the accurate knowledge about the optical properties (absorption coefficient μa [mm^-1], reduced scattering coefficient μs′ [mm^-1], etc.) of the target tissue is important for the understanding and prediction of propagation and distribution of light in tissues, since the PDT efficacy depends on the photon propagation through irradiated tissues. The objective of this study is determination of the optical properties of the tissues treated by PDT in the wavelength range from 350 nm to 1000 nm using double integrating sphere measurement system combined with an inverse Monte Carlo method. In this study, mouse tumor tissues obtained from subcutaneously implanted Lewis lung carcinoma cell line were treated by a normal PDT procedure using a Talaporfin Sodium (Laserphyrin^®, MEIJI SEIKA KAISHA, LTD.) as a photosensitizer and a laser diode (UM1000 Dental_665, JENOPTIK unique-mode GmbH) with a wavelength of 664 nm.
7 days after PDT, the μs′ at the wavelength of 664nm was increased from 0.64mm^-1 to 1.24mm^-1. The optical penetration depth in the treated tissues was estimated about 44% lower than that in the tissues before PDT at the wavelength of 664nm. To ensure the effective procedure, an adjustment of the laser parameter for the decrease of penetration depth is recommended for a second PDT.

View full abstract

Photodynamic therapy (PDT) for urinary bladder cancer has not yet been established as a standard clinical treatment. As urinary bladder cancer frequently proliferates multifocally and grows diffusely, homogeneous irradiation of the mucosal membrane on the bladder wall is an important factor for the success of whole bladder wall PDT. In this study, we fabricated a Homogenous Irradiation Fiber Probe (HIFiP) for illuminating the urinary bladder wall and evaluated the PDT effect. Using rat orthotopic urinary bladder tumor models, we confirmed that widespread and homogenous irradiation in the mucosa of the urinary bladder wall was achieved using the newly developed fiber probe. The anti-tumor effect of PDT using HIFiP was approximately 2 times as that using a control fiber (flat cleaved end). An effective PDT for the urinary bladder cancer is expected by the combination of HIFiP and a tumor-selective photosensitizer.

View full abstract

Objective: The aim was to compare over one year outcome of carbon dioxide laser vaporization of the inferior turbinate for perennial allergic rhinitis patients with or without allergen specific immunotherapy.
Method: 96 patients underwent laser vaporization from April 1999 until March 2009. We analyzed 68 patients who were following-up over one year. The changes of their clinical symptoms and the medication were recorded periodically.
Result: The remarkable improvent ratio of the nasal symptoms was obtained in the immunotherapy group (84.0%) and in non-immunotherapy group (79.1%) at 3 months after laser surgery. In immunotherapy group, the only one patient (4%) needed laser surgery over 3 times. On the other hand, over 3 times operations have been needed in 21 patients (48.8%) without immunotherapy,
Conclusion: These results suggest that concominant immunotherapy can not influence the short term of clinical efficacy of laser surgery. However, the immunotherapy may be usefull for preventing recurrence after laser surgery.

View full abstract

Percutaneous laser disectomy was operated blindly within the center of disc space. The inability of direct observation of the decompressed nerve or the targeted pathoanatomy under the laser irradication has limited its use. At this time, with nerve operating or working channel spine endoscopes, the laser is used mainly as an adjunctive tool for hemostasis and tissue ablation during endoscopic procedures in foreign countries. On the other hand, there has been considerable number of lumbar disc hernia cases operated with laser in Japan. As a significant number of ineffective cases with laser has been reported, some academic societies have given warning to the use of this laser. But more notice needs to be taken to the fact that current status of the laser directomy has not been acknowledged in Japan. We conducted a questionnaire survey . About 80% of laser surgery for lumbar disc hernia has been done in two private hospitals. Both of Disc hernia with radiculopathy and low back pain without radiculopathy are included into the indication, though the pathogenesis of them is different. We have to keep on discussing the indication and the way of laser use.

View full abstract

Discogenic low back pain is believed to result from degenerated and disrupted outer annular fibers that lead to a vicious cycle of persistent inflammation, matrix damage, and sensitization of developed annular nociceptors. Discogenic low back pain has thus far been clinically challenging and expensive to treat. The aim of this research was to determine the outcome of laser disc irradiation for discogenic low back pain.
A total of 11 patients were selected on the basis of clinical findings and provocative disc block. These patients underwent percutaneous lumbar diode laser irradiation to the affected disc. Mean total irradiation energy at one disc was 740±2.51 J (range, 610?960 J). These patients were analyzed by using the Oswestry disability index (ODI) score and the visual analog pain index (VAPI) score.
The average ODI score prior to laser irradiation was 50.3±9.4. The average ODI scores at 1 day, 3 months, 6 months, 12 months, 18 months, and 24 months post laser irradiation were 18.6±11.2, 13.6±4.5, 12.5±5.5, 11.8±5.3, 10.5±2.3, and 10.5±2.3, respectively. The average VAPI score prior to laser irradiation was 7.6±1.2. The average VAPI scores 1 day, 3 months, 6 months, 12 months, 18 months, and 24 months post laser irradiation were 3.1±2.4, 2.4±0.9, 2.7±1.2, 2.1±0.7, 2.1±0.8, and 2.1±0.9, respectively. Clinical benefit was considered significant in those patients statistically for 24 months post laser irradiation.
The long-term benefit of laser irradiation for discogenic pain suggests that a mechanism other than a mechanical one causes chronic back and sciatic pain. The efficacy of this treatment method might be due to the thermal effect and a reduction in intradiscal pressure, irritative products, and nociceptors.

View full abstract

The purpose of this study is to evaluate the influence on the intervertebral disc cells after Ho: YAG laser irradiation using three- dimensional culture system and to detect the photoacoustic and photothermal effects on percutaneous laser disc decompression (PLDD). We studied the disc cell reaction from the metabolic point of view to investigate these effects on three-dimensional cultured disc cells obtained from 30 Japanese white rabbits. A pulsed Ho: YAG laser was delivered through a single silica glass fiber. To investigate the acoustic effect, the acoustic transducer constructed with polyvinylidene fluoride (PVdF) film and acoustic absorber were used to detect the stress waves. Simultaneously, thermocouple and thermography were used to investigate photothermal effect caused by laser irradiation. Using the measurement system, we detected the photoacoustic effect, and the linear correlation between PG Synthesis / LDH release and stress amplitude was evident. Meanwhile, we could also detect the temperature elevation caused by laser irradiation using thermography, however the linear correlation between PG Synthesis / LDH release and thermal load was not evident. Laser- disc cell interaction was investigated in terms of cell metabolism and physical agents as the thermal load and the stress waves, and could be useful to optimize the irradiation condition using the measurement system.

View full abstract

Objective of this study is the estimation of optimal therapeutic wavelength for percutaneous laser disk decompression. The optical properties measurement system which was combined with a double integrating sphere optical setup and an inverse Monte Carlo method was developed. The absorption coefficient spectrum and reduced scattering coefficient spectrum of a human herniated nucleus pulposus in the visible and near-infrared wavelength range were determined. As a result of a comparison to normal nucleus pulposus, reduced scattering coefficient spectrum of a human herniated nucleus pulposus showed an increasing tendency in the short wavelength region. Compared to a conventional wavelength, Nd: YAG laser with a wavelength at 1064nm, it was confirmed that a laser with a visible short wavelength realized a safe PLDD from the estimated result of light diffusion lengths calculated by the optical properties.

View full abstract