Performance comparison of a state-of-the-art neuro-SPET scanner and a dedicated neuro-PET scanner

Abstract

The physical performances of two current state-of-the-art scanners dedicated to functional imaging of the brain, one a single-photon emission tomography (SPET) scanner and the other a positron emission tomography (PET) scanner, have been compared under identical conditions. The aim of the study was to compare the capabilities of the devices under conditions resembling the routine clinical environment, as well as to consider other issues such as radiation burden for some common investigations. Both systems have slightly less than 11-cm axial fields of view. The PET system can be operated in a septa-less (3D) mode as well as conventionally with septa (2D). The spatial resolution of both devices was less than 8 mm in all dimensions in scattering media. On average, the PET scanner's resolution was approximately 10%-15% better than the SPET system. Energy resolution on the SPET system was superior due the scintillator used [NaI(Tl)]. Sensitivity in air with a line source on the PET system was found to be approximately 150 times greater in 3D and approximately 25 times greater in 2D than with the SPET system. A normal subject was studied on each system in an attempt to obtain the highest quality data possible for a subjective comparison. It is clear that, while PET retains the advantages of more desirable radiopharmaceuticals and higher sensitivity, the quality obtainable from SPET devices has improved markedly. SPET may prove as useful for many clinical investigations.

The relevance of interictal rCBF brain SPECT in temporal lobe epilepsy: Diagnostical value and effects of spatial resolution

“…2 '• 22 Therefore, the main factor for sensitivity is considered to be spatial resolution, if the two relatively wide-spread procedures F-18-DG-PET and rCBF-SPECT are compared and recent reports claimed that modern SPECT systems dedicated for brain SPECT have largely filled the described gap of sensitivity between PET and SPECT. 12 In this study sensitivity of interictal rCBF-SPECT increased from 69% for low spatial resolution SPECT systems to 84% for moderate-to high-resolution SPECT systems. The advanced MRI system also showed increased sensitivity.…”

“…12 Furthermore, reports focussing on interictal evaluation of epilepsy showed comparable sensitivity between PET and SPECT in this indication' 3" 4 and ictal rCBF-SPECT has proven to show superior sensitivity in the evaluation of epilepsy, regardless which imaging procedure has been used tor correlation.…”

In Vivo Follow-up of Rat Tumor Models with 2-Deoxy-2-[F-18]fluoro-d-glucose/Dual-Head Coincidence Gamma Camera Imaging

“…Animal PET scanners have a spatial resolution range of about 2 mm [10,11], while dedicated PET have a spatial resolution range of about 4Y6 mm [12,13] and DHC have a resolution of about 5 to 8 mm [14Y16]. Dedicated PET cameras and animal PET cameras also have a better detection limit because their sensitivity (in air with a line source) is 150 times greater in 3-D and 25 times greater in 2-D than DHC [15]. If the sensitivity and the maximum true coincidence counting rate are relatively lower in DHC compared to dedicated PET scanner [16], DHC with large NaI crystals allows the acquisition of whole rat body images when animal PET cameras need several bed positions [17].…”

Central benzodiazepine receptor imaging and quantitation with single photon emission computerised tomography: SPECT

“…Antagonists, such as flumazenil, have no effect on GABAergic transmission, but antagonise the effects of agonists and inverse agonists by competing for the receptor site. Apart from the benzodiazepines, other drugs such as barbiturates, ethanol, steroids, antihelminthics and some anaesthetic compounds also produce at least part of their Table 1 Comparison of some aspects of PET and SPECT &dquo;Comparison of spatial resolution of state-of-the-art brain dedicated SPECT and PET scanners, showed that, on average, the PET scanner had 10-15% better resolution (Bailey et al, 1994). pharmacological effects by allosterically modulating GABAAinduced chloride ion flux (Sieghart, 1992).…”

“…SPECT is cheaper and is becoming more available in both clinical and research settings. The main SPECT developments in the last decade or so have been directed towards improving the counting capabilities and spatial resolution of systems (Bailey et al, 1994), the ultimate aim being quantitative imaging using appropriate radioligands (Blokland, Reiber and Pauwels, 1992;Blokland, 1994).…”