Robustness of Anatomically Guided Pixel-by-Pixel Algorithms for Partial Volume Effect Correction in Positron Emission Tomography

Service Hospitalier Frédéric Joliot, CEA, Orsay, France.
Journal of Cerebral Blood Flow & Metabolism (Impact Factor: 5.41). 06/1999; 19(5):547-59. DOI: 10.1097/00004647-199905000-00009
Source: PubMed


Several algorithms have been proposed to improve positron emission tomography quantification by combining anatomical and functional information in a pixel-by-pixel correction scheme. The precision of these methods when applied to real data depends on the precision of the manifold correction steps, such as full-width half-maximum modeling, magnetic resonance imaging-positron emission tomography registration, tissue segmentation, or background activity estimation. A good understanding of the influence of these parameters thus is critical to the effective use of the algorithms. In the current article, the authors present a monodimensional model that allows a simple theoretical and experimental evaluation of correction imprecision. The authors then assess correction robustness in three dimensions with computer simulations, and evaluate the validity of regional SD as a correction performance criterion.

Download full-text


Available from: Bernard Bendriem, Mar 19, 2014
21 Reads
  • Source
    • "Considering our PET-CT clinical studies, we found that this occurs for a limited number of cases (96% of lesions were spherical and 80% with a uniform uptake). For those lesions that have hypometabolic characteristics (e.g., low grade tumour in the cerebral white matter), other PVE correction methods (e.g., based on image-guided segmentation or preprocessing) can be applied (e.g., [19, 20, 27, 48–51]). "
    [Show abstract] [Hide abstract]
    ABSTRACT: We have developed, optimized, and validated a method for partial volume effect (PVE) correction of oncological lesions in positron emission tomography (PET) clinical studies, based on recovery coefficients (RC) and on PET measurements of lesion-to-background ratio (L/B m ) and of lesion metabolic volume. An operator-independent technique, based on an optimised threshold of the maximum lesion uptake, allows to define an isocontour around the lesion on PET images in order to measure both lesion radioactivity uptake and lesion metabolic volume. RC are experimentally derived from PET measurements of hot spheres in hot background, miming oncological lesions. RC were obtained as a function of PET measured sphere-to-background ratio and PET measured sphere metabolic volume, both resulting from the threshold-isocontour technique. PVE correction of lesions of a diameter ranging from 10 mm to 40 mm and for measured L/B m from 2 to 30 was performed using measured RC curves tailored at answering the need to quantify a large variety of real oncological lesions by means of PET. Validation of the PVE correction method resulted to be accurate (>89%) in clinical realistic conditions for lesion diameter > 1 cm, recovering >76% of radioactivity for lesion diameter < 1 cm. Results from patient studies showed that the proposed PVE correction method is suitable and feasible and has an impact on a clinical environment.
    09/2013; 2013:780458. DOI:10.1155/2013/780458
  • Source
    • "As other PVC methods based on anatomical information, the accuracy of this method can be affected by errors in a series of data processing steps, such as image realignment, segmentation, and parcelation. The sensitivity to this type of errors has been investigated by other groups for various PVC methods [8] [22] [23] [24] , and we would expect the effects to be similar for p-PVC. Methods for resolution recovery that do not utilize anatomical data are obviously not susceptible to this type of errors. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The ability to correctly quantify activity concentration with single photon emission computed tomography (SPECT) is limited by its spatial resolution. Blurring of data between adjacent structures, which is known as partial volume effects, can be compensated for by utilizing high resolution structural information from other imaging modalities such as CT or MRI. Previously developed partial volume correction (PVC) methods normally assume a spatially invariant point spread function. In SPECT this is not a good approximation, since the resolution varies with the distance from the collimator. A new method, p-PVC, was developed in this paper, which takes into account the distance dependent blurring. The method operates in projection space and is combined with filtered back-projection (FBP) reconstruction. Results from simulations show that similar quantitative results could be obtained with p-PVC+FBP as with OSEM with resolution recovery, although with better structural definition and an order of magnitude faster.
    Tsinghua Science & Technology 02/2010; 15(1):50-55. DOI:10.1016/S1007-0214(10)70008-0
  • Source
    • "Cortical activation and pallidal DBS in PD P Payoux et al three-dimensional acquisition of 63 transaxial slices. Spatial resolution after reconstruction was 4.5 in the transaxial direction and 4.1 mm and axial direction (Brix et al, 1997; Strul and Bendriem, 1999). To measure rCBF, 300 MBq of H 2 15 O were administered for each 80-secs emission scan. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Continuous stimulation of the globus pallidus (GP) has been shown to be an effective treatment for Parkinson's disease (PD). We used the fact that the implanted quadripolar leads contain electrodes within the GPi and GPe to investigate the clinical effects of acute high-frequency stimulation applied in these nuclei and changes in regional cerebral blood flow (rCBF) as an index of synaptic activity. In five patients treated by chronic GP stimulation, we compared the effects on PD symptoms and the changes in rCBF at rest and during paced right-hand movements, with and without left GPe or GPi stimulation. Although improving contralateral rigidity and akinesia, left GPe stimulation decreased rCBF in the left cerebellum and lateral premotor cortex at rest and significantly increased it in the left primary sensorimotor cortex (SM1) during movement. In contrast, left ventral GPi stimulation, which improved rigidity and worsened akinesia, decreased rCBF in the left SM1, premotor area, anterior cingulum, and supplementary motor area but did not modify the movement-related activation. GPe stimulation seems to result in a reduced activity of motor-related areas and the facilitation of motor cortex activation during movement, the latter component being absent during GPi stimulation, and this may explain the observed worsening of akinesia.
    Journal of cerebral blood flow and metabolism: official journal of the International Society of Cerebral Blood Flow and Metabolism 09/2008; 29(2):235-43. DOI:10.1038/jcbfm.2008.107 · 5.41 Impact Factor
Show more