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    Recent applications of robotics in the feld of prostate brachytherapy are seeding the future and could potentially lead to a fully automated prostate brachytherapy surgery. Currently, a typical prostate brachytherapy surgery involves the implantation of upwards of 100 radioactive I-125 seeds by a surgeon. This review supplies background information on prostate biology, brachytherapy of the prostate, robotic brachytherapy, and transrectal ultrasound. Subsequently, it examines the physics involved in ultrasound, radiation from an I-125 source, dosimetry, and robotics. A current semi-automated robotic brachytherapy system is examined in detail and a discussion on future improvements is outlined. Finally, future work to improve prostate brachytherapy is postulated, most notably, phantom optimization using polyvinyl alcohol cryogel. The future of robotic brachytherapy lies in the advent of more sophisticated robotics. This review will give the reader a superior understanding of brachytherapy and its recent robotic advancements. Hopefully, this review will generate new ideas needed to advance prostate brachytherapy procedures leading to more accurate dosimetry, faster procedure time, less ionizing radiation received by surgery staff, more rapid patient recovery, and an overall safer procedure.
    Prostate brachytherapy
    Chapter 7 discusses the use of brachytherapy for prostate cancer, and covers both permanent low dose rate (LDR) and temporary high dose rate (HDR) brachytherapy, which both use a similar template-based transrectal ultrasound-guided transperineal technique and therefore represent similar technical challenges.
    Dose rate
    Detection of brachytherapy seeds plays a key role in dosimetry for prostate brachytherapy. However, seed localization using B-mode transrectal ultrasound (TRUS) still remains a challenge for prostate brachytherapy, mainly due to the small size of brachytherapy seeds in the relatively low-quality B-mode TRUS images. In this paper, we propose a new solution for brachytherapy seed detection using 3-D ultrasound. A 3-D reflected power image is computed from ultrasound RF signals, instead of conventional B-mode images. Then, implanted seeds are segmented in 3-D local search spaces that are determined by a priori knowledge, e.g., needle entry points and seed placements. Needle insertion tracks are also detected locally by the Hough transform. Experimental results show that the proposed solution works well for seed localization in a prostate phantom implanted according to a realistic treatment plan with 136 seeds from 26 needles.
    Prostate brachytherapy
    Hough Transform
    Citations (23)
    Abstract Brachytherapy is a form of radiotherapy whereby a radioactive source is used inside or at short distance from the tumor. There are three different forms of brachytherapy: interstitial, intracavitary, and skin therapy. In interstitial brachytherapy, the radioactive sources are implanted inside and throughout the tumor volume; in intracavitary brachytherapy the sources are placed in the body cavities very close to the tumor; while in skin therapy the sources are placed on the skin surface. Conventionally, brachytherapy implants have delivered the radiation at a low dose rate (dose rates of <1 Gy/h). Low dose‐rate (LDR) interstitial implants can be temporary (meaning that the radioactive sources are left in place for a period of time, usually a few days, and then removed) or permanent (left in place without removal), while intracavitary implants are temporary. The advent of methods to deliver the dose at a much higher dose rates, in the range of 1–5 Gy/min, brought an increase in the use of brachytherapy. All high dose‐rate (HDR) brachytherapy treatments are temporary and treatments are administered using discrete fractions.
    Dose rate
    Citations (0)