Development of a new brain PET scanner based on single event data acquisition

Isobe, Takashi; Yamada, R.; Shimizu, Katsuji; Saito, Akinori; Ote, Kibo; Sakai, K.; Moriya, Toshio; Yamauchi, H.; Omura, T.; Watanabe, M.

doi:10.1109/nssmic.2012.6551810

Cited by 24 publications

(14 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With the dramatic improvements in data transfer speed that have occurred in recent years (such as USB 3.1 which has a transfer rate up to 1.25 GB/s), and improvements in date storage speeds using solid state drives (SSD), it is feasible to collect single events from the PET scanner [31]–[32]. As the event time-stamps are included in the event data, our proposed LED-based time-walk correction method can be applied to these data to improve the timing resolution without any additional measurements from the PET scanner.…”

Section: Conclusion and Discussionmentioning

confidence: 99%

A Time-Walk Correction Method for PET Detectors Based on Leading Edge Discriminators

Schmall

Judenhofer

et al. 2017

IEEE Trans. Radiat. Plasma Med. Sci.

View full text Add to dashboard Cite

The leading edge timing pick-off technique is the simplest timing extraction method for PET detectors. Due to the inherent time-walk of the leading edge technique, corrections should be made to improve timing resolution, especially for time-of-flight PET. Time-walk correction can be done by utilizing the relationship between the threshold crossing time and the event energy on an event by event basis. In this paper, a time-walk correction method is proposed and evaluated using timing information from two identical detectors both using leading edge discriminators. This differs from other techniques that use an external dedicated reference detector, such as a fast PMT-based detector using constant fraction techniques to pick-off timing information. In our proposed method, one detector was used as reference detector to correct the time-walk of the other detector. Time-walk in the reference detector was minimized by using events within a small energy window (508.5 – 513.5 keV). To validate this method, a coincidence detector pair was assembled using two SensL MicroFB SiPMs and two 2.5 mm × 2.5 mm × 20 mm polished LYSO crystals. Coincidence timing resolutions using different time pick-off techniques were obtained at a bias voltage of 27.5 V and a fixed temperature of 20 °C. The coincidence timing resolution without time-walk correction were 389.0 ± 12.0 ps (425 –650 keV energy window) and 670.2 ± 16.2 ps (250–750 keV energy window). The timing resolution with time-walk correction improved to 367.3 ± 0.5 ps (425 – 650 keV) and 413.7 ± 0.9 ps (250 – 750 keV). For comparison, timing resolutions were 442.8 ± 12.8 ps (425 – 650 keV) and 476.0 ± 13.0 ps (250 – 750 keV) using constant fraction techniques, and 367.3 ± 0.4 ps (425 – 650 keV) and 413.4 ± 0.9 ps (250 – 750 keV) using a reference detector based on the constant fraction technique. These results show that the proposed leading edge based time-walk correction method works well. Timing resolution obtained using this method was equivalent to that obtained using a reference detector and was better than that obtained using constant fraction discriminators.

show abstract

Section: Conclusion and Discussionmentioning

confidence: 99%

A Time-Walk Correction Method for PET Detectors Based on Leading Edge Discriminators

Schmall

Judenhofer

et al. 2017

IEEE Trans. Radiat. Plasma Med. Sci.

View full text Add to dashboard Cite

show abstract

“…We have developed a new brain PET scanner, whose detector ring is formed with 32 four-layer DOl detectors [5]. Fig.…”

Section: Application To a Brain Pet Scannermentioning

confidence: 99%

Development of a high-resolution four-layer DOI detector using MPPCs for brain PET

Omura

Moriya

Yamada

et al. 2012

2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC)

Self Cite

View full text Add to dashboard Cite

A new high-resolution four-layer DOl detector using MPPCs for brain PET scanner has been developed. The new depth of interaction (DOl) detector was designed to compose of four layers of detector units, which were lined up five axially. Each of the detector units consists of a LYSO scintillator array finely segmented of 1.2 mm and an 8 x 8 array of multi-pixel photon counters (MPPCs), which are one of the products of silicon photomultiplier family. The MPPC is so compact and insensitive to gamma-ray that the detector units can be piled up with a small gap between each scintillator array in the depth direction. In order to have the detector in every layer equally sensitive to gamma-ray, the scintillator thickness was designed at 3 mm, 4 mm, 5 mm and 8 mm toward the bottom respectively, and the total thickness was 20 mm. We adopted an internal focused laser processing technique to a monolithic LYSO scintillator and fabricated a 2D segmented array of 32 x 32 with 1.2 mm pitch in 38.4 mm square cross-section. Each detector layer has independently front end circuits including ASICs for MPPCs and signal processing circuits for crystal identification, energy and timing detection.Each data set of four layers are fed into data interface circuits placed behind detector layers and transferred to a data acquisition unit as formatted list-mode data. The performance of the four-layer DOl detector has been evaluated. The coincidence timing resolution of the detector, with a reference BaF2 detector, was obtained 850 ps FWHM. The average energy resolution value was 24.5% at 511 keY. The crystal separation with finely segmented L YSO scintillator was also good enough at each layer.

show abstract

“…Silicon photomultipliers (SiPMs) are considered a good substitute for photomultiplier tubes (PMTs) and avalanche photodiodes (APDs) in PET especially for PET/MR applications (Lewellen 2008, Roncali and Cherry 2011and Disselhorst et al 2014. Among the different SiPM-based PET systems under investigation (Isobe et al 2013, Shao et al 2014and Mackewn et al 2015, very high resolution PET systems for smallanimal imaging applications remain an important category (Yamamoto et al 2013), especially for imaging the mouse brain, which is poorly resolved with current technology. A high resolution PET detector can be achieved using a high light output scintillator array (such as cerium-doped lutetium oxyorthosilicate (LSO) or cerium-doped lutetium-yttrium oxyorthosilicate (LYSO) with SiPM arrays or with position-sensitive SiPM (PS-SiPM).…”

Section: Introductionmentioning

confidence: 99%

Evaluation of linearly-graded SiPMs for high resolution small-animal PET

Yang

Berg

et al. 2015

Biomed. Phys. Eng. Express

View full text Add to dashboard Cite

The performance of a position-sensitive silicon photomultiplier (PS-SiPM), a linearly graded silicon photomultiplier (LG-SiPM), was evaluated for use as a high resolution small-animal PET detector. This SiPM utilizes a combined resistive /capacitive current divider and a double quenching resistor in every SiPM microcell for position estimation. In this paper, using a 6×6 array of 0.45×0.45×6 mm 3 polished cerium-doped lutetium-yttrium oxyorthosilicate (LYSO) crystals, coupled to the center of the SiPM, we evaluated the detector performance, with a focus on applications in very high resolution small-animal PET. Measurements of signal-to-noise ratio, energy resolution and flood histogram quality were performed at different over-voltages (from ∼1.0 V to ∼7.5 V) and different temperatures (-6.5 °C, 0 °C, 10 °C and 20 °C) to find the optimal working conditions. The timing resolution was measured at an over-voltage of 3.0 V and at different temperatures. The results showed that all the crystals in the LYSO array could be clearly resolved, even at room temperature (20 °C). The best flood histogram quality was obtained at an over-voltage of ∼3.0 V and a temperature of -6.5 °C. Under these conditions, the average energy resolution, signal-to-noise ratio, and coincidence timing resolution were 22.3±2.7%, 269.0±24.2 and 828±43 ps, respectively.

show abstract

Development of a new brain PET scanner based on single event data acquisition

Cited by 24 publications

References 4 publications

A Time-Walk Correction Method for PET Detectors Based on Leading Edge Discriminators

A Time-Walk Correction Method for PET Detectors Based on Leading Edge Discriminators

Development of a high-resolution four-layer DOI detector using MPPCs for brain PET

Evaluation of linearly-graded SiPMs for high resolution small-animal PET

Contact Info

Product

Resources

About