Papers by Aaron McFarland
2006 IEEE Nuclear Science Symposium Conference Record, 2006
ABSTRACT Time alignment is critical to the operation of high performance PET systems. Optimizing ... more ABSTRACT Time alignment is critical to the operation of high performance PET systems. Optimizing the countrate performance of a given system requires proper timing to minimize the effects of random events as early in the datastream as possible to reduce electronic deadtime. Siemens Inveon PET systems high countrate performance is made possible by their exceedingly tight timing tolerance of 1.22 ns FWHM, allowing the use of an optimal 3.5 ns coincidence window. This paper describes the hardware capabilities used to align the system as well as the processing techniques used to perform the alignment.
2006 IEEE Nuclear Science Symposium Conference Record, 2006
... system to small animal imaging has led to its commercial success, but its performance is ... ... more ... system to small animal imaging has led to its commercial success, but its performance is ... TN 37932 USA (telephone: +1 865 218 1613, e-mail: [email protected] ... Through the use of high-speed digital signaling techniques, communication and data between EPMs is ...
Current Organic Chemistry, 2013
![Research paper thumbnail of A “dose on demand” Biomarker Generator for automated production of [18F]F− and [18F]FDG](https://a.academia-assets.com/images/blank-paper.jpg)
Applied Radiation and Isotopes, 2014
The University of Oklahoma-College of Pharmacy has installed the first Biomarker Generator (BG75)... more The University of Oklahoma-College of Pharmacy has installed the first Biomarker Generator (BG75) comprising a self-shielded 7.5-MeV proton beam positive ion cyclotron and an aseptic automated chemistry production and quality control module for production of [(18)F]F(-) and clinical [(18)F]FDG. Performance, reliability, and safety of the system for the production of "dose on demand" were tested over several months. No-carrier-added [(18)F]F(-) was obtained through the (18)O(p,n)(18)F nuclear reaction by irradiation (20-40 min) of a >95% enriched [(18)O]H2O target (280 μl) with a 7.5-MeV proton beam (3.5-5.0 μA). Automated quality control tests were performed on each dose. The HPLC-based analytical methods were validated against USP methods of quality control. [(18)F]FDG produced by BG75 was tested in a mouse tumor model implanted with H441 human lung adenocarcinoma cells. After initial installment and optimization, the [(18)F]F(-) production has been consistent since March 2011 with a maximum production of 400 to 450 mCi in a day. The average yield is 0.61 mCi/min and 0.92 mCi/min at 3.8 µA and 5 µA, respectively. The current target window has held up for over 25 weeks against >400 bombardment cycles. [(18)F]FDG production has been consistent since June 2012 with an average of six doses/day in an automated synthesis mode (RCY≈50%). The release criteria included USP-specified limits for pH, residual solvents (acetonitrile/ethanol), kryptofix, radiochemical purity/identity, and filter integrity test. The entire automated operation generated minimal radiation exposure hazard to the operator and environment. As expected, [(18)F]FDG produced by BG75 was found to delineate tumor volume in a mouse model of xenograft tumor. In summary, production and quality control of "[(18)F]FDG dose on demand" have been accomplished in an automated and safe manner by the first Biomarker Generator. The implementation of a cGMP quality system is under way towards the ANDA submission and first clinical use of [(18)F]FDG produced by BG75.
2020 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)
Arterial blood sampling (ABS) is considered the gold-standard method for evaluating the arterial ... more Arterial blood sampling (ABS) is considered the gold-standard method for evaluating the arterial input function in dynamic PET studies. However, ABS is invasive and associated with a high complexity and risks. Alternatively, image-derived input function (IDIF) methods can be employed to simplify protocols and enhance adoption of dynamic PET in research and clinical practice. However IDIF methods require scanning for longer periods at the scanner bed, can be limited by the short axial field-of-view (FOV) of the vast majority of modern clinical PET systems and are susceptible to noise and partial volume effects due to the large ring diameter and large detector elements size of modern clinical PET systems. In this work we are evaluating the physical performance of the SynchroPET ArterialPET™ scanner (Stony Brook, NY, USA), a human wrist standalone cylindrical PET prototype system of 9 cm diameter ring and 1.73 cm axial FOV, capable of 4D PET imaging of the human wrist to enhance existing IDIF methods. The NEMA NU4-2008 performance evaluation protocol was selected to assess spatial resolution. system sensitivity and image quality. All PET data were acquired in list-mode, later sorted into 3D sinograms and reconstructed with an open-source 3D-OSEM algorithm with all data corrections included (decay, randoms, normalization, attenuation and scatter) when applicable. The average of radial and transaxial resolution was 1.49mm and 2.78mm FWHM at 5mm and 25mm radial distance from the center, respectively, while the respective axial resolution was 2.84mm and 4.69mm FWHM. The system sensitivity was 3.54 kcps/MBq. In terms of image quality, all hot rod sources were distinguishable with recovery coefficients of 21.71% and 96.21% for the 1mm and 5mm rod sources, respectively. ArterialPET can be utilized to extract IDIF data from human arteries in the wrist where a 2-5mm diameter is expected. Further clinical studies are needed to assess potential enhancement of IDIF methods.
2007 IEEE Nuclear Science Symposium Conference Record, 2007
The QuickSilver Event Processing Module (EPM) is a key component of a high performance data acqui... more The QuickSilver Event Processing Module (EPM) is a key component of a high performance data acquisition platform from Siemens Molecular Imaging (Knoxville, TN) for use in the Inveon™ line of multimodal PET and SPECT preclinical imaging systems. The card's main purpose is to condition, digitize and process incoming analog pulses from PMT or APD based PET or SPECT detectors. Analog pulses from a detector are digitized using a 100MHz continuous sampling ADC and read into a Xilinx Virtex II Pro FPGA for processing. The FPGA performs digital integration, baseline offset correction and pileup rejection. Because these functions are done in the digital domain, different algorithms can be quickly re-implemented and tested. The EPM has the ability to capture raw event ADC samples, allowing for the quick development and comparison of new algorithms in software on actual event samples. The Inveon™ small animal PET scanner uses a larger LSO block detector and new analog front end than previous generation scanners which increases the likelihood of pileup events. The digital pulse processing methods presented here have been evaluated to obtain the best energy and positioning performance from the high pixel count Inveon™ detectors while maintaining high stability across countrates.
ABSTRACT Time alignment is critical to the operation of high performance PET systems. Optimizing ... more ABSTRACT Time alignment is critical to the operation of high performance PET systems. Optimizing the countrate performance of a given system requires proper timing to minimize the effects of random events as early in the datastream as possible to reduce electronic deadtime. Siemens Inveon PET systems high countrate performance is made possible by their exceedingly tight timing tolerance of 1.22 ns FWHM, allowing the use of an optimal 3.5 ns coincidence window. This paper describes the hardware capabilities used to align the system as well as the processing techniques used to perform the alignment.
… Record, 2006. IEEE, 2006
... system to small animal imaging has led to its commercial success, but its performance is ... ... more ... system to small animal imaging has led to its commercial success, but its performance is ... TN 37932 USA (telephone: +1 865 218 1613, e-mail: [email protected] ... Through the use of high-speed digital signaling techniques, communication and data between EPMs is ...
Introduction: In general, [18F]FDG quality assurance methods require the reporting of at least 11... more Introduction: In general, [18F]FDG quality assurance methods require the reporting of at least 11 different elements in the monograph published by the U.S. Pharmacopeia (USP). These quality tests may require the maintenance and use of as many as three different pieces of laboratory analytical equipment: Gas chromatograph, HPLC, and radio TLC. Together, this equipment adds cost of building a lab, let alone the maintenance and calibration requirements. Herein, we present an automated quality control method based upon a single HPLC system which samples 200 $mu$L radiopharmaceutical product directly from the final product vial and reports the product pH, radiochemical identity, radiochemical purity, kryptofix, FDG, acetonitrile, and ethanol concentrations. Experimental: Traditional quality control equipment were validated and used for comparison purposes. In addition the Kryptofix Color-Spot test was used as a pass fail comparison against our method. The Biomarker Generator Quality Cont...
2007 IEEE Nuclear Science Symposium Conference Record, 2007
Abstract The Siemens MI PET research program is investigating scintillation detectors based on re... more Abstract The Siemens MI PET research program is investigating scintillation detectors based on relatively new solid-state avalanche photo diode (APD) technology. The relatively slow rise time of APDs compared to photomultiplier tubes (PMTs), combined with large ...
Journal of Radioanalytical and Nuclear Chemistry, 2015
ABSTRACT
2006 IEEE Nuclear Science Symposium Conference Record, 2006
... The ERS is a Compact PCI card that is installed in a 3U embedded PC chassis in ... II. HARDWA... more ... The ERS is a Compact PCI card that is installed in a 3U embedded PC chassis in ... II. HARDWARE DESCRIPTION The core of the ERS is based around the Xilinx Virtex II Pro ... with Siemens Molecular Imaging, Knoxville, TN 37932 USA (telephone: +1 865 218 1627, e-mail: Aaron ...
2007 IEEE Nuclear Science Symposium Conference Record, 2007
The QuickSilver Event Processing Module (EPM) is a key component of a high performance data acqui... more The QuickSilver Event Processing Module (EPM) is a key component of a high performance data acquisition platform from Siemens Molecular Imaging (Knoxville, TN) for use in the Inveon™ line of multimodal PET and SPECT preclinical imaging systems. The card's main purpose is to condition, digitize and process incoming analog pulses from PMT or APD based PET or SPECT detectors. Analog pulses from a detector are digitized using a 100MHz continuous sampling ADC and read into a Xilinx Virtex II Pro FPGA for processing. The FPGA performs digital integration, baseline offset correction and pileup rejection. Because these functions are done in the digital domain, different algorithms can be quickly re-implemented and tested. The EPM has the ability to capture raw event ADC samples, allowing for the quick development and comparison of new algorithms in software on actual event samples. The Inveon™ small animal PET scanner uses a larger LSO block detector and new analog front end than previous generation scanners which increases the likelihood of pileup events. The digital pulse processing methods presented here have been evaluated to obtain the best energy and positioning performance from the high pixel count Inveon™ detectors while maintaining high stability across countrates.
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Papers by Aaron McFarland