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The term venous translucence (or translumination) has been used in phlebology since 1996 by surgeon Pedro Fernandes Neto during ambulatory clinical exams in Brazil. His results were published in the annals of the national and international congresses of angiology. Venous translucence is the process of reflective image visualization of veins by light, which reaches up to the superficial venous system. It is a non-invasive method. Since it is a simple, low-cost technique it can be repeated as needed, which is useful in disease-process monitoring. It is a new diagnostic procedure, still undergoing investigation; more analysis is necessary to hone its technical aspects. Venous translucence is based on optical physics. It is caused by the refraction, absorption and reflection of light (whose principle is the dispersion and absorption of light). The color which is not absorbed is reflected, and is the one that is seen. Therefore, venous translumination is based on the incidence of luminousity on the vein, where part of the light is absorbed and another reflected (supplying a silhouette of the vein in question). ==Technical aspects== Steps must be taken to avoid artifacts or luminous pollution during the venous translumination. Reflection and refraction of light are important to avoid distorted images which can appear during a scanning. Many are due to inappropriate sources which would provoke light loss similar to luminous pollution. During the venous translumination, the amount of reflected light depends on the index of refraction which can be altered by the venous thrombosis. Certain types of lamps process more dispersion than reflection, and therefore favor the formation of artifacts. Another aspect is the inability to be obtain useful images with a fiber-optic source due to the high irradiation frequency. It is also known that the reflection in an optic fiber source is initially processed internally. Certain instruments are not specific to obtain reflected images. The illumination of the skin by distant infrared light, without the impression of the source on the skin, does not reveal a diagnostic image. The translumination transductor must be in direct contact with the skin. The process should be similar to that used in Doppler ultrasonography. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Venous translucence」の詳細全文を読む スポンサード リンク
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