During the past 13 years, 2,154 outpatients have been treated with the carbon dioxide laser (MEDILASER MODEL·445) by a single surgeon. All were managed as out-patients under general anesthesia. With the advent of carbon dioxide laser, the treatment of hemorrhoid, rectal anterior mucosal prolapse, anorectal fistulas and pilonidal disease have become simple. Laser beam must be chosen to suit surgical objectives, such as for incisions with focused beams and for ablations with defocused spots. Carbon dioxide laser surgery is quite useful for anorectal disases, because hospitalization is unnecessary owing to decrease pain after operation, it minimizes surgical scar and makes the patient faster return to his work.

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Bactericidal effects by laser irradiation on staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and other bacterial strains have been reported by some researchers, but little attention has been given to the bactericidal mechanism by laser irradiation. In this report, bactericidal mechanism using Argon laser was examined by means of the following method.
a. Bactericidal effects by Argon laser were evaluated by the formation of growth-inhibitory circle of bacteria.
b. The relationship between irradiation output and irradiation time of Argon laser was examined in 5 bacteria including MRSA.
c. The morphological changes in MRSA after laser irradiation were observed by using the transmission electron microscope. As controls, non-irradiated bacteria, heat-treated bacteria and ultraviolet irradiated bacteria were also observed.
d. The bacterial colony were irradiated by laser. The bacteria were stained with acridine orange, and then were compared with non-irradiated bacteria by observing with fluorescence microscope.
e. Change of DNA by laser irradiation on MRSA was studied using Agarose gel electrophoresis.
The results of the experiments were as follows.
a. All bacteria showed a growth inhibitory circle after laser irradiation.
b. By changing irradiation output and irradiation time, we found that there was a close relationship between the total energy per unit area and the appearance of a bactericidal effect, and that Pseudomonas aeruginosa had high sensitivity to the Argon laser compared with other bacteria.
c. The cytoplasm and nucleoid of the bacteria were seen to be higher electron dense lesion. These feature was in good agreement with the image of the cytoplasm of bacteria after heating.
d. After irradiation, fluorescence which acridine orange emitted did not presented difference between irradiated group and non-irradiated group. e. DNA band pattern of MRSA on electrophoresis was not changed after laser irradiation.
In this study, it is suggested that the bactericidal effects on MRSA by Argon laser may be caused mainly by heat rather than photo-dynamic action and that laser may not directly influence band pattern of the DNA in bacteria.

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Development of medical technologies have been supported by optics. Historically optical technology enter a revolutionary era in the latter half of the 20th century. Quantum optics was introduced by the invention of ruby laser in 1960. Application of high energy density of laser light has been frequently used in medicine. Recently, frequency dependent photosensitive characteristics of cells has been applied. Techniques such as optical fiber, light computing and photon detection begin to be applied in-medical domain. These techniques include fundamentally laser technology and optoelectric principles. In the article, 1 describe short introductions for laser techniques related to microstructures, because the bioiogical systems consist microparts and we must develop the handling technologies in medicine.

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Laser manipulation technique which is developed by Ashkin is widely applied to various branch of studies; for example, the region of micro-machine, micro-chemistry. manipulating of cell and DNA, the experiment of cell fusion, and measurement of the generating power of actin myosin complex, a principle of laser trapping is based on the momentum transfer of refraction of light. In the other word, refraction of light yields the force of trapping, and its magnitude is roughly estimated pico-newton (pN), since, the magnitude of power which acts on micro-objects has as same order as that of laser trapping force, we can use this power in order to manipulate various small objects. and recently, this technique is greatly contributing to analyzing the mechanism of muscle contraction.

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Confocal laser scanning microscopy (CLSM) has been used in various fields of medical and biological sciences. In this article, applications of CLSM for the biological transport study in the biological cells and tissues were reviewed, mainly from the authors' recent studies. At first, the basic idea of the CLSM was briefly described, and then dye selection for the physiological study was summarized. For the physiological applications, we mentioned about two case-studies: 1) the macromolecules transport into endothelial cells, and 2) Ca²⁺ mobilization in the median giant fiber of an earthworm. At last, future applications of the CLSM for the biological transport were also indicated.

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