Nanotechnology has made all our imagination come true. Israeli scientists have successfully worked on a medical robot 1mm in diameter that can not only creep through the nose and ears but also make their way through veins and arteries. These robots will be used for brachytherapy - a process where cancer patients are exposed to short-distance radiotherapy from a source placed inside or next to the area requiring treatment. For instance, brachytherapy is a common treatment method for localized prostate cancer as well as cancers in the head and neck. Unlike the prior robots, these robots can successfully to crawl against the bloodstream without any problem thanks to the tiny arms that stretch out, gripping onto vessel walls without causing any harm or injury to the patient.

These robots make their way through your blood stream so known as a submarine robot.
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