科學(xué)家最近發(fā)現(xiàn)一種利用超聲振動(dòng)來捕獲腫瘤影像地方法。這種技術(shù)涉及對(duì)膠質(zhì)對(duì)象使用超聲振動(dòng)來成像，這種膠質(zhì)對(duì)象通常是圓形的，比如血細(xì)胞和懸浮在液體中的顆粒。

美國(guó)布朗大學(xué)的研究人員正在進(jìn)行一項(xiàng)研究，他們將一束超聲波射入身體某個(gè)區(qū)域來產(chǎn)生射頻信號(hào)，然后經(jīng)過處理反應(yīng)出膠質(zhì)對(duì)象的空間特征。這項(xiàng)技術(shù)在組織與血液之間產(chǎn)生500倍對(duì)比，使得該技術(shù)有助于腫瘤成像，因?yàn)楦鶕?jù)科學(xué)家的說法，腫瘤組織比正常組織具有更多的血管。

直接包繞在顆粒周圍體液的電荷與顆粒表面電荷相反。這使得顆粒聚集在一起。當(dāng)聲波撞擊膠質(zhì)狀物體的時(shí)候，導(dǎo)致環(huán)繞顆粒周圍的體液產(chǎn)生振動(dòng)。振動(dòng)電荷產(chǎn)生交互電流，從而產(chǎn)生射頻波譜。

與此相反的是，傳統(tǒng)超聲成像利用不同密度物質(zhì)導(dǎo)致聲波速度的變化來顯示不同組織的影像。根據(jù)科學(xué)家的說法，這種新技術(shù)在2～5年之后即可用于臨床乳腺影像檢查。這項(xiàng)研究成果發(fā)表在2004年11月20日的《應(yīng)用物理通信》上。

Ultrasonic Vibrations Capture Tumor Images
 
Scientists have discovered a way to utilize ultrasonic vibrations to capture images of tumors. The technique involves using ultrasonic vibrations to image colloidal objects, which are spherical in shape, such as blood cells and particles that are suspended in fluid.

The investigators, from Brown University (Providence, RI, USA), are performing a study in which they shoot a beam of ultrasound through an area of the body to generate a radiofrequency signal, which they then process to produce a spatial representation of colloidal objects. The technique produces a 500-fold contrast between tissue and blood, which makes it potentially useful for imaging tumors because tumors have more blood vessels than normal tissue, according to the scientists.

The fluid directly surrounding a particle carries an electric charge opposite the charge on the surface of the particle. This keeps particles from bunching together. When sound waves hit colloidal objects, they cause the fluid around the particles to oscillate. The oscillating charge produces an alternating current, which products radiofrequency waves.

In contrast, conventional ultrasonic imaging utilizes alterations in speed of the sound waves caused by substances with different densities to image different kinds of tissue. This new technique could be ready for clinical use in mammogram technology in two to five years, according to the scientists. Their study was published in the November 29, 2004, issue of the journal Applied Physics Letter.