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X-ray mammography is an important diagnostic tool in the fightagainst breast cancer , but it has certain drawbacks that limit its effectiveness. Forexample, it can give in false positive and negative results; italso exposes women to low doses of ionizing radiation, which -while accepted as safe - still carry some risk. In the first phase of clinical testing of a new imaging device,researchers from Netherlands' University of Twente and MedischSpectrum Twente Hospital in Oldenzaal used photoacoustics -light-induced sound - rather than ionizing radiation to detect andvisualize breast tumors. The team's preliminary results, which wereconducted on 12 patients with diagnosed malignancies and reportedin the Optical Society's (OSA) open-access journal Optics Express , provide proof-of-concept support that the technology candistinguish malignant tissue by providing high-contrast images oftumors. "While we're very early in the development of this new technology,it is promising. Our hope is that these early results will one daylead to the development of a safe, comfortable, and accuratealternative or adjunct to conventional techniques for detectingbreast tumors," explained researcher Michelle Heijblom, a Ph.D.student at the University of Twente. Photoacoustics, a hybrid optical and acoustical imaging technique,builds on the established technology of using red and infraredlight to image tissue and detect tumors. This technology, calledoptical mammography, reveals malignancies because blood hemoglobinreadily absorbs the longer, redder wavelengths of light, whichreveals a clear contrast between blood-vessel dense tumor areas andnormal vessel environments. However, it is difficult to target thespecific area to be imaged with this approach. As a means of improving this, the researchers combined thelight-based system's ability to distinguish between benign andmalignant tissue with ultrasound to achieve superior targetingability. The result of their refinements is a specializedinstrument, the Twente Photoacoustic Mammoscope (PAM), which wasfirst tested in 2007. The device is built into a hospital bed, where the patient liesprone and positions her breast for imaging. Laser light at awavelength of 1,064 nanometers scans the breast. Because there isincreased absorption of the light in malignant tissue thetemperature slightly increases. With the rise in temperature,thermal expansion creates a pressure wave, which is detected by anultrasound detector placed on one side of the breast. The resultingphotoacoustic signals are then processed by the PAM system andreconstructed into images. These images reveal abnormal areas ofhigh intensity (tumor tissue) as compared to areas of low intensity(benign tissue). This is one of the first times that the techniquehas been tested on breast cancer patients. By comparing the photoacoustic data with conventional diagnosticX-rays, ultrasound imaging, MRI, and tissue exams, the researchersshowed that malignancies produced a distinct photoacoustic signalthat is potentially clinically useful for making a diagnosis ofbreast cancer. The team also observed that the photoacousticcontrast of the malignant tissue is higher than the contrastprovided by the conventional X-ray mammographies. In looking to the future, notes Heijblom, "PAM needs some technicalimprovements before it is a really valuable clinical tool fordiagnosis or treatment of breast cancer. Our next step is to makethose improvements and then evaluate less obvious potential tumors,benign lesions, and normal breasts with it." Additional References Citations. We are high quality suppliers, our products such as Poly Bubble Envelope Manufacturer , Metallic Bubble Mailer for oversee buyer. To know more, please visits Kraft Bubble Mailer.
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