BrachyView: Proof‐of‐principle of a novel in‐body gamma camera for low dose‐rate prostate brachytherapy

Abstract

. (2013). BrachyView: Proof-of-principle of a novel in-body gamma camera for low dose-rate prostate brachytherapy. Medical Physics, 40 (4), 041709-1-041709-9.Brachyview: proof-of-principle of a novel in-body gamma camera for low dose-rate prostate brachytherapy AbstractPurpose: The conformity of the achieved dose distribution to the treatment plan strongly correlates with the accuracy of seed implantation in a prostate brachytherapy treatment procedure. Incorrect seed placement leads to both short and long term complications, including urethral and rectal toxicity. The authors present BrachyView, a novel concept of a fast intraoperative treatment planning system, to provide real-time seed placement information based on in-body gamma camera data. BrachyView combines the high spatial resolution of a pixellated silicon detector (Medipix2) with the volumetric information acquired by a transrectal ultrasound (TRUS). The two systems will be embedded in the same probe so as to provide anatomically correct seed positions for intraoperative planning and postimplant dosimetry. Dosimetric calculations are based on the TG-43 method using the real position of the seeds. The purpose of this paper is to demonstrate the feasibility of BrachyView using the Medipix2 pixel detector and a pinhole collimator to reconstruct the real-time 3D position of low dose-rate brachytherapy seeds in a phantom. Methods: BrachyView incorporates three Medipix2 detectors coupled to a multipinhole collimator. Three-dimensionally triangulated seed positions from multiple planar images are used to determine the seed placement in a PMMA prostate phantom in real time. MATLAB codes were used to test the reconstruction method and to optimize the device geometry. Results: The results presented in this paper show a 3D position reconstruction accuracy of the seed in the range of 0.5-3 mm for a 10-60 mm seed-to-detector distance interval (Z direction), respectively. The BrachyView system also demonstrates a spatial resolution of 0.25 mm in the XY plane for sources at 10 mm distance from Medipix2 detector plane, comparable to the theoretical value calculated for an equivalent gamma camera arrangement. The authors successfully demonstrated the capability of BrachyView for real-time imaging (using a 3 s data acquisition time) of different brachytherapy seed configurations (with an activity of 0.05 U) throughout a 60 × 60 × 60 mm3 Perspex prostate phantom. Conclusions: The newly developed miniature gamma camera component of BrachyView, with its high spatial resolution and real time capability, allows accurate 3D localization of seeds in a prostate phantom. Combination of the gamma camera with TRUS in a single probe will complete the BrachyView system. © 2013 American Association of Physicists in Medicine. Keywords dose, low, camera, gamma, prostate, body, rate, novel, principle, proof, brachyview, brachytherapy Disciplines Engineering | Science and Technology Studies Publication DetailsPetasecca, M., Loo, K. J., Safavi-Naeini, M., Han, Z., Metcalfe, P. E., Meikle...

Preliminary Monte Carlo Investigation of Using Ir-192 as the Source for Real Time Imaging Purpose

“…Safavi-Naeini et al . designed a BrachyView in vivo imaging device for brachytherapy [15] [16] [17], which can achieve sub-millimeter accuracy with an equivalent acquisition time of 0.5 s and their results support the use of the Ir-192 source as an imaging source. However, since BrachyView is an in-body device, its application is limited in other treatment sites, such as with breast HDR.…”

“…Safavi-Naeini el al . developed a BrachyView in-body imaging system for HDR prostate brachytherapy in 2013 and 2015 [15] [16] [17], which was capable of providing imaging, localization and dose validation. However, due to physical space limitations, the device may not be suitable for all types of HDR treatment.…”

A simulation study of BrachyShade, a shadow-based internal source tracking system for HDR prostate brachytherapy

“…One of the most promising innovations for HDR PBT QA is the BrachyView family of devices, developed at the University of Wollongong's Centre for Medical Radiation Physics, with two separate variants proposed for HDR and LDR PBT by Safavi-Naeini et al 2013and Petasecca et al (2013) and Alnaghy et al (2017), respectively. HDR BrachyView performs real-time monitoring of the position of the 192 Ir source during HDR prostate brachytherapy treatment.…”

Radioactive source localization employing resistive electrode array (REA) detector

“…Other potential uses of the REA localization capability is in Radioisotope Identification (RIID) in health safety and national security [6]. Various detectors have been used in radioactive source localization [7][8][9][10][11][12][13][14]: radiosensitive films, at panel detectors (Electronic Portal Imaging Device (EPID)), gamma camera, photon counting detectors, scintillators, and others. Typically the detector is at a fixed position and radioactive sources are either static or moving.…”