Technical performance evaluation of a human brain PET/MRI system

Kolb, Armin; Wehrl, Hans F.; Hofmann, Matthias; Judenhofer, Martin S.; Eriksson, Lars; Ladebeck, Ralf; Lichy, Matthias P.; Byars, L.G.; Michel, Christian; Schlemmer, Heinz Peter; Schmand, M.; Claussen, Claus D.; Sossi, Vesna; Pichler, Bernd J.

doi:10.1007/s00330-012-2415-4

Cited by 148 publications

(123 citation statements)

References 28 publications

Supporting

Mentioning

120

Contrasting

Order By: Relevance

“…For example, Siemens Healthcare did propose a "Brain PET" system that was based on a PET ring insert for a 3 T MR system [104]. More recently, a SiPM-based PET insert has been developed for integration with any MR scanner [105].…”

Section: Organ-specific System Design and Total-body Systemsmentioning

confidence: 99%

Hybrid Imaging: Instrumentation and Data Processing

et al. 2018

View full text Add to dashboard Cite

State-of-the-art patient management frequently requires the use of non-invasive imaging methods to assess the anatomy, function or molecular-biological conditions of patients or study subjects. Such imaging methods can be singular, providing either anatomical or molecular information, or they can be combined, thus, providing "anato-metabolic" information. Hybrid imaging denotes image acquisitions on systems that physically combine complementary imaging modalities for an improved diagnostic accuracy and confidence as well as for increased patient comfort. The physical combination of formerly independent imaging modalities was driven by leading innovators in the field of clinical research and benefited from technological advances that permitted the operation of PET and MR in close physical proximity, for example. This review covers milestones of the development of various hybrid imaging systems for use in clinical practice and small-animal research. Special attention is given to technological advances that helped the adoption of hybrid imaging, as well as to introducing methodological concepts that benefit from the availability of complementary anatomical and biological information, such as new types of image reconstruction and data correction schemes. The ultimate goal of hybrid imaging is to provide useful, complementary and quantitative information during patient work-up. Hybrid imaging also opens the door to multi-parametric assessment of diseases, which will help us better understand the causes of various diseases that currently contribute to a large fraction of healthcare costs.

show abstract

Section: Organ-specific System Design and Total-body Systemsmentioning

confidence: 99%

Hybrid Imaging: Instrumentation and Data Processing

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Hybr id PET/MR systems have recently been introduced into clinical practice and are attracting increasing interest in the research and clinical communities (1)(2)(3). While PET/CT is an established hybrid modality with a wide range of applications, specific application trends for PET/MR are currently under investigation (4-7).…”

mentioning

confidence: 99%

MR-Based Attenuation Correction Methods for Improved PET Quantification in Lesions Within Bone and Susceptibility Artifact Regions

et al. 2013

Self Cite

View full text Add to dashboard Cite

Hybrid PET/MR systems have recently entered clinical practice. Thus, the accuracy of MR-based attenuation correction in simultaneously acquired data can now be investigated. We assessed the accuracy of 4 methods of MR-based attenuation correction in lesions within soft tissue, bone, and MR susceptibility artifacts: 2 segmentation-based methods (SEG1, provided by the manufacturer, and SEG2, a method with atlas-based susceptibility artifact correction); an atlas-and pattern recognition-based method (AT&PR), which also used artifact correction; and a new method combining AT&PR and SEG2 (SEG2wBONE). Methods: Attenuation maps were calculated for the PET/MR datasets of 10 patients acquired on a whole-body PET/MR system, allowing for simultaneous acquisition of PET and MR data. Eighty percent iso-contour volumes of interest were placed on lesions in soft tissue (n 5 21), in bone (n 5 20), near bone (n 5 19), and within or near MR susceptibility artifacts (n 5 9). Relative mean volume-of-interest differences were calculated with CT-based attenuation correction as a reference. Results: For soft-tissue lesions, none of the methods revealed a significant difference in PET standardized uptake value relative to CT-based attenuation correction (SEG1, 22.6% 6 5.8%; SEG2, 21.6% 6 4.9%; AT&PR, 24.7% 6 6.5%; SEG2wBONE, 0.2% 6 5.3%). For bone lesions, underestimation of PET standardized uptake values was found for all methods, with minimized error for the atlas-based approaches (SEG1, 216.1% 6 9.7%; SEG2, 211.0% 6 6.7%; AT&PR, 26.6% 6 5.0%; SEG2wBONE, 24.7% 6 4.4%). For lesions near bone, underestimations of lower magnitude were observed (SEG1, 212.0% 6 7.4%; SEG2, 29.2% 6 6.5%; AT&PR, 24.6% 6 7.8%; SEG2wBONE, 24.2% 6 6.2%). For lesions affected by MR susceptibility artifacts, quantification errors could be reduced using the atlas-based artifact correction (SEG1, 254.0% 6 38.4%; SEG2, 215.0% 6 12.2%; AT&PR, 24.1% 6 11.2%; SEG2w-BONE, 0.6% 6 11.1%). Conclusion: For soft-tissue lesions, none of the evaluated methods showed statistically significant errors. For bone lesions, significant underestimations of 216% and 211% occurred for methods in which bone tissue was ignored (SEG1 and SEG2). In the present attenuation correction schemes, uncorrected MR susceptibility artifacts typically result in reduced attenuation values, potentially leading to highly reduced PET standardized uptake values, rendering lesions indistinguishable from background. While AT&PR and SEG2wBONE show accurate results in both soft tissue and bone, SEG2wBONE uses a two-step approach for tissue classification, which increases the robustness of prediction and can be applied retrospectively if more precision in bone areas is needed. Hybr id PET/MR systems have recently been introduced into clinical practice and are attracting increasing interest in the research and clinical communities (1-3). While PET/CT is an established hybrid modality with a wide range of applications, specific application trends for PET/MR are currently under investigation (4-7). MR-based atten...

show abstract

“…Preliminary results show that the quality of PET and MRI is adequate [14,15,[49][50][51]. A detailed description of these methodological issues is beyond the scope of this review.…”

Section: Pet and Mri Performancementioning

confidence: 99%

Molecular neuroimaging with PET/MRI

Garibotto¹,

Förster

Haller³

et al. 2013

Clin Transl Imaging

View full text Add to dashboard Cite

Hybrid PET/MRI is a recently developed technique, which is attracting growing interest among the medical community owing to its potential clinical and research applications. PET/MRI is of special interest for neuroscience, given that PET and MRI are the neuroimaging methods of choice for many clinical and scientific applications. The first clinical studies conducted have tested the performance of PET/MRI in oncology indications, neurodegenerative disorders and epilepsy, using aminoacidic tracers and somatostatin-receptor imaging ( 68 Ga-DOTATOC), 18 F-fluorodeoxyglucose ( 18 F-FDG), and 11 C-flumazenil, respectively, and shown that the acquisition of both brain PET and MRI can be performed in a single session on a hybrid PET/MRI system achieving quality comparable to that of PET/CT and MRI acquired separately, but with some important advantages. Combined acquisition of PET and MRI maximizes the clinical information and optimizes the registration of both modalities, while minimizing patient discomfort. Sparing the patient the CT scan can reduce radiation exposure while the accurate coregistration due to the identical positioning opens new windows for better region-specific evaluation of PET data, particularly when acquired with tracers that provide little anatomical information. PET and MRI parameters can be systematically combined for diagnostic interpretation and new options concerning partial volume and motion correction can be exploited. There are still open issues, such as the selection of clinical indications, the influence of the combined design on the performance of each modality, and, in particular, the validation of quantitative PET measures with respect to attenuation correction. Overall, PET/MRI hybrid imaging is an exciting new modality and potentially the future modality of choice for neuroimaging investigations.

show abstract

Technical performance evaluation of a human brain PET/MRI system

Abstract: • Combination of PET and MRI is a new emerging imaging technology. • Evaluated brain PET/MRI enables uncompromised imaging performance. • PET/MRI aims to provide multiparametric imaging allowing acquisition of morphology and metabolism.

Cited by 148 publications

References 28 publications

Hybrid Imaging: Instrumentation and Data Processing

Hybrid Imaging: Instrumentation and Data Processing

MR-Based Attenuation Correction Methods for Improved PET Quantification in Lesions Within Bone and Susceptibility Artifact Regions

Molecular neuroimaging with PET/MRI

Contact Info

Product

Resources

About