PET Demonstrator for a Human Brain Scanner Based on Monolithic Detector Blocks

Sarasola, I.; Mendes, P. Rato; Acilu, P. Garcia de; Canadas, M.; Vela, O.; Cela, J. M.; Oller, J.C.; Núñez, Luis A.; Willmott, C.; Pérez, J. M.

doi:10.1109/tns.2011.2152856

Cited by 15 publications

(21 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For PET applications, multiple tests using APD detectors were performed [38,39,40,41,42,43], showing increased acceptance and support for APD-based scanners over PMTs moving forward. Although the gain of APDs was not as good as in PMTs, they offered more benefits such as reduced cost, smaller size, and insensitivity to magnetic fields.…”

Section: Avalanche Photodiodes (Apds)mentioning

confidence: 99%

“…Another such organ-specific project was a brain PET [43] insert for existing MRI equipment. Compared to dual-modality PET/CT systems, PET/MRI systems can reduce the risk of ionizing radiation, provide better soft tissue contrast of grey and white matter, and correct for attenuation and scattering of PET images [43]. The building block of this scanner consisted of large, dual layer monolithic LYSO:Ce scintillators of trapezoidal shape coupled to a pair of Hamamatsu S8550-02 APD arrays.…”

Section: Avalanche Photodiodes (Apds)mentioning

confidence: 99%

See 1 more Smart Citation

Sensors for Positron Emission Tomography Applications

Jiang

Chalich

Deen

2019

Sensors

View full text Add to dashboard Cite

Positron emission tomography (PET) imaging is an essential tool in clinical applications for the diagnosis of diseases due to its ability to acquire functional images to help differentiate between metabolic and biological activities at the molecular level. One key limiting factor in the development of efficient and accurate PET systems is the sensor technology in the PET detector. There are generally four types of sensor technologies employed: photomultiplier tubes (PMTs), avalanche photodiodes (APDs), silicon photomultipliers (SiPMs), and cadmium zinc telluride (CZT) detectors. PMTs were widely used for PET applications in the early days due to their excellent performance metrics of high gain, low noise, and fast timing. However, the fragility and bulkiness of the PMT glass tubes, high operating voltage, and sensitivity to magnetic fields ultimately limit this technology for future cost-effective and multi-modal systems. As a result, solid-state photodetectors like the APD, SiPM, and CZT detectors, and their applications for PET systems, have attracted lots of research interest, especially owing to the continual advancements in the semiconductor fabrication process. In this review, we study and discuss the operating principles, key performance parameters, and PET applications for each type of sensor technology with an emphasis on SiPM and CZT detectors—the two most promising types of sensors for future PET systems. We also present the sensor technologies used in commercially available state-of-the-art PET systems. Finally, the strengths and weaknesses of these four types of sensors are compared and the research challenges of SiPM and CZT detectors are discussed and summarized.

show abstract

Section: Avalanche Photodiodes (Apds)mentioning

confidence: 99%

Section: Avalanche Photodiodes (Apds)mentioning

confidence: 99%

Sensors for Positron Emission Tomography Applications

Jiang

Chalich

Deen

2019

Sensors

View full text Add to dashboard Cite

show abstract

“…We have developed a simple PET demonstrator for evaluating the performance of the FlexToT ASIC in the readout of PET detector blocks, similar to one previously used by our group at CIEMAT [9]. The demonstrator consists of two detector boxes aligned face to face, each containing a set of FlexToT front-end readout boards with scintillators mounted on the SiPM matrices, at a face-to-face nominal distance of 200 mm.…”

Section: E Pet Demonstrator Setupmentioning

confidence: 99%

Evaluation of the FlexToT ASIC on the readout of SiPM matrices and scintillators for PET

Castilla

Cela

Comerma-Montells

et al. 2013

2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC)

View full text Add to dashboard Cite

We have designed FlexToT, a flexible application specific integrated circuit (ASIC) using time-over-threshold (ToT) techniques for the readout of silicon photomultiplier (SiPM) arrays in positron emission tomography (PET) detectors. The FlexToT ASIC accommodates 16 independent channels in a small die size (2.93 mm by 2.54 mm) with low power consumption (10 mW per channel), providing output signals whose duration is proportional to the current amplitude at its inputs. The threshold, gain and other parameters can be independently set for each channel in a flexible configuration that can be tailored to different applications and devices. Herein we present the results on the evaluation of the FlexToT ASIC operating as front-end electronics for SiPM arrays S11828-3344M from Hamamatsu (Japan) coupled to LYSO:Ce scintillators in a simple PET tomograph demonstrator. Each detector block is composed of a LYSO:Ce matrix coupled to 4 SiPM arrays in a 2x2 mosaic, totaling 64 pixels (8x8) which are read out by 4 FlexToT ASICs. Using this demonstrator we have obtained PET images of 22 Na point sources with spatial resolutions better than 2 mm full width at half maximum (FWHM), validating our design of the FlexToT ASIC on the readout of SiPM matrices and scintillators in PET applications. P 978-1-4799-0534-8/13/$31.00 ©2013 IEEE

show abstract

“…On the other hand, insufficient sensitivity results in a low signal‐to‐noise ratio (SNR), which restricts the capability of performing high‐resolution and dynamic imaging 32 . Although several dedicated brain PET scanners have been developed for research 33–37 as well as proof‐of‐principle simulations to assess their capabilities, 38–40 these systems still suffer from trade‐offs among cost, sensitivity, spatial resolution, and timing resolution.…”

Section: Introductionmentioning

confidence: 99%

High‐resolution and high‐sensitivity PET for quantitative molecular imaging of the monoaminergic nuclei: A GATE simulation study

et al. 2022

View full text Add to dashboard Cite

Purpose Quantitative in vivo molecular imaging of fine brain structures requires high‐spatial resolution and high‐sensitivity. Positron emission tomography (PET) is an attractive candidate to introduce molecular imaging into standard clinical care due to its highly targeted and versatile imaging capabilities based on the radiotracer being used. However, PET suffers from relatively poor spatial resolution compared to other clinical imaging modalities, which limits its ability to accurately quantify radiotracer uptake in brain regions and nuclei smaller than 3 mm in diameter. Here we introduce a new practical and cost‐effective high‐resolution and high‐sensitivity brain‐dedicated PET scanner, using our depth‐encoding Prism‐PET detector modules arranged in a conformal decagon geometry, to substantially reduce the partial volume effect and enable accurate radiotracer uptake quantification in small subcortical nuclei. Methods Two Prism‐PET brain scanner setups were proposed based on our 4‐to‐1 and 9‐to‐1 coupling of scintillators to readout pixels using 1.5×1.5×20$1.5 \times 1.5 \times 20$ mm3 and 0.987×0.987×20$0.987 \times 0.987 \times 20$ mm3 crystal columns, respectively. Monte Carlo simulations of our Prism‐PET scanners, Siemens Biograph Vision, and United Imaging EXPLORER were performed using Geant4 application for tomographic emission (GATE). National Electrical Manufacturers Association (NEMA) standard was followed for the evaluation of spatial resolution, sensitivity, and count‐rate performance. An ultra‐micro hot spot phantom was simulated for assessing image quality. A modified Zubal brain phantom was utilized for radiotracer imaging simulations of 5‐HT1A receptors, which are abundant in the raphe nuclei (RN), and norepinephrine transporters, which are highly concentrated in the bilateral locus coeruleus (LC). Results The Prism‐PET brain scanner with 1.5 mm crystals is superior to that with 1 mm crystals as the former offers better depth‐of‐interaction (DOI) resolution, which is key to realizing compact and conformal PET scanner geometries. We achieved uniform 1.3 mm full‐width‐at‐half‐maximum (FWHM) spatial resolutions across the entire transaxial field‐of‐view (FOV), a NEMA sensitivity of 52.1 kcps/MBq, and a peak noise equivalent count rate (NECR) of 957.8 kcps at 25.2 kBq/mL using 450–650 keV energy window. Hot spot phantom results demonstrate that our scanner can resolve regions as small as 1.35 mm in diameter at both center and 10 cm away from the center of the transaixal FOV. Both 5‐HT1A receptor and norepinephrine transporter brain simulations prove that our Prism‐PET scanner enables accurate quantification of radiotracer uptake in small brain regions, with a 1.8‐fold and 2.6‐fold improvement in the dorsal RN as well as a 3.2‐fold and 4.4‐fold improvement in the bilateral LC compared to the Biograph Vision and EXPLORER, respectively. Conclusions Based on our simulation results, the proposed high‐resolution and high‐sensitivity Prism‐PET brain scanner is a promising cost‐effective candidate ...

show abstract

PET Demonstrator for a Human Brain Scanner Based on Monolithic Detector Blocks

Cited by 15 publications

References 19 publications

Sensors for Positron Emission Tomography Applications

Sensors for Positron Emission Tomography Applications

Evaluation of the FlexToT ASIC on the readout of SiPM matrices and scintillators for PET

High‐resolution and high‐sensitivity PET for quantitative molecular imaging of the monoaminergic nuclei: A GATE simulation study

Contact Info

Product

Resources

About