Victor Rykalin's research while affiliated with Proton Power, Inc. and other places

Publications (13)

Article
Purpose: Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield Units of patient tissues into proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly...
Article
Purpose: Verification of patient specific proton stopping powers obtained in the patient's treatment position can be used to reduce the distal and proximal margins needed in particle beam planning. Proton radiography can be used as a pre-treatment instrument to verify integrated stopping power consistency with the treatment planning CT. Although a...
Article
Purpose To reduce imaging artifacts and improve image quality of a specific proton computed tomography (pCT) prototype scanner by combining pCT data acquired at two different incident proton energies to avoid protons stopping in sub-optimal detector sections. Methods Image artifacts of a prototype pCT scanner are linked to protons stopping close t...
Article
Purpose: To demonstrate a proton imaging system based on well-established fast scintillator technology to achieve high performance with low cost and complexity, with the potential of a straightforward translation into clinical use. Methods: The system tracks individual protons through one (X, Y) scintillating fiber tracker plane upstream and dow...
Preprint
Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield Units of patient tissues to proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly measuring pr...
Preprint
Verification of patient specific proton stopping powers obtained in the patient treatment position can be used to reduce the distal margins needed in particle beam planning. Proton radiography can be used as a pre-treatment instrument to verify integrated stopping power consistency with the treatment planning CT. Although a proton radiograph is a p...
Preprint
Purpose: To demonstrate a proton imaging system based on well-established fast scintillator technology to achieve high performance with low cost and complexity, with the potential of a straightforward translation into clinical use. Methods: The system tracks individual protons through one (X, Y) scintillating fiber tracker plane upstream and downst...
Article
Full-text available
Proton computed tomography (pCT) has high accuracy and dose efficiency in producing spatial maps of the relative stopping power (RSP) required for treatment planning in proton therapy. With fluence-modulated pCT (FMpCT), prescribed noise distributions can be achieved, which allows to decrease imaging dose by employing object-specific dynamically mo...
Article
One of the major challenges to proton beam therapy at this time is the uncertainty of the true range of a clinical treatment proton beam as it traverses the various tissues and organs in a human body. This uncertainty necessitates the addition of greater “margins” to the planning target volume along the direction of the beam to ensure safety and tu...
Conference Paper
Full-text available
CONCLUSION Proton CT has the potential to substantially improve the range accuracy of proton beams and to provide a low-dose imaging modality for daily image guidance. Careful evaluation of this novel technique is underway. BACKGROUND Proton CT is a novel tomographic imaging modality, which has become a realistic possibility with the increasing av...
Conference Paper
BACKGROUND Proton CT can provide improved dose accuracy in treatment planning for proton therapy. In addition, lower doses than X-ray CT are theoretically possible and streaking artifacts will be reduced or eliminated. The first proton CT scanner has now been tested in a proton beam and the results are presented. This paper focuses on the detector...

Citations

... To ensure conservatism in annual dose estimates, it is assumed all proton imaging will be acquired in pCT mode, as opposed to pRad mode. The number of protons per tomography has been estimated to be 7.5 × 10 8 based on the 1.5 × 10 7 protons used to acquire a proton tomography of a pig's head, 4 and noting that the noise levels will likely need to be reduced in the clinical setting. The conservative workload calculations also assume that every treatment fraction includes a pCT image acquisition. ...
... Two of the most advanced scanners currently in operation are the pCT collaboration's phase-II scanner 35 and the commercially oriented ProtonVDA (pVDA) scanner. [42][43][44] The phase-II scanner features silicon-strip tracking modules registering both the location and direction of protons before and after the object, and a five-stage energy detector. The pVDA scanner uses scintillating fibers tracking modules, which register only position with initial direction vectors derived from the beam geometry, and a single-stage energy detector requiring variation of the proton beam energy. ...
... For the imaging runs presented in this work, three incident energies (118 , 160, and 187 MeV) were acquired throughout the field of view, which resulted in an increased imaging dose, but could be avoided in case prior knowledge of the scanned object is available. 52 Each of the beam energies covered a specific WEPL range in the object scanned in this experiment, with some overlapping WEPLs between them, as indicated in Table 1. The first overlap region extends from approximately 50 to about 90 mm and is covered by 118 and 160 MeV beams, respectively. ...
... Various designs have been proposed over the years, see Refs. [5][6][7][8][9][10], to pave the way forward. Recently, A Super Thin RAnge (ASTRA) telescope has been proposed as a next-generation detector for pCT, its main advantages being its speed (aims at 100 MHz) and its fine segmentation (3 × 3 mm 2 bars) meant to accurately reconstruct the proton energies by range and to efficiently deal with pile-up. ...
... 35 For operation of the scanner with scanned pencil beams, the local count rate increases and a pileup-free operation was demonstrated for count rates up to 400 kHz. 47,48 For the purpose of this study, a 200 MeV broad proton beam was utilized with the phase-II scanner. More details about the beam characteristics are given in Section 2.6 ...
... This work was focused on a proton detector prototype being developed by ProtonVDA [12][13][14]. ProtonVDA has developed a highly efficient and inexpensive proton radiography system based on solid state photomultipliers and fiber detectors. One of the main advantages of this system is the lower, compared to similar X-ray imaging systems, equivalent dose received by the patient. ...