References of "Blocklet, Didier"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailReproductibilité de la mesure de la fraction d'éjection ventriculaire gauche par ventriculographie isotopique lors d'un changement de caméra
Seret, Alain ULg; Lisart, Jean; Blocklet, Didier

in Médecine Nucléaire : Imagerie Fonctionnelle et Métabolique (2003), 27(5), 251-256

The reproducibility of the left ventricular ejection fraction measure by equilibrium radionuclide angiocardiography has been evaluated when a large field of view camera is used instead of the small field ... [more ▼]

The reproducibility of the left ventricular ejection fraction measure by equilibrium radionuclide angiocardiography has been evaluated when a large field of view camera is used instead of the small field of view that has been used for 15 years in the service. The results have been analyzed using correlation curves, the Bland-Altman method and a paired t test. Linear regression between the left ejection fraction is FEVG(large field of view) = 0.961 FEVG(small field of view) + 5.0 (r = 0.935). Intra-operator reproducibility (mean difference = - 0.15 ± 2.02) and inter-operator reproducibility (absolute value of the mean difference smaller than 1.1 and standard deviation smaller that 2.5) have been measured for the 4 nurses that are entitled to practice this examination in the case of the large field of view camera. Finally, the reproducibility between two different acquisitions with the large field of view camera has been investigated and the following result has been obtained: FEVG(2) = 0.955 FEVG(1) + 3.178 (r = 0.948). Therefore, the reproducibility of the left ejection fraction measure was estimated to be within the expected limits and no correction for the camera change is applied to the long-term follow-up of the patients. [less ▲]

Detailed reference viewed: 168 (4 ULg)
Full Text
Peer Reviewed
See detail180 degrees Pinhole SPET with a tilted detector and OS-EM reconstruction: phantom studies and potential clinical applications
Seret, Alain ULg; Defrise, Michel ULg; Blocklet, Didier

in European Journal of Nuclear Medicine (2001), 28(12), 1836-1841

This study investigated the feasibility of ordered subsets expectation maximisation (OS-EM) reconstruction of pinhole single-photon emission tomography (SPET) acquired with a tilted detector head and a ... [more ▼]

This study investigated the feasibility of ordered subsets expectation maximisation (OS-EM) reconstruction of pinhole single-photon emission tomography (SPET) acquired with a tilted detector head and a 180 degrees orbit. Phantom and patient data were recorded using a standard single-head camera. Reconstructions were performed using a dedicated OS-EM algorithm. Reconstructed images of line, uniformity and Picker's thyroid phantoms showed that the geometry, physical size and uniformity of the radioactive objects were preserved. For the range of radius corresponding to the patient studies, the measured full-widths at half-maximum lay between 4.90+/-0.25 mm and 6.05+/-0.25 mm. Finally, the gain in resolution associated with the use of the pinhole collimator instead of a parallel-hole collimator was highlighted in a parathyroid exploration and in a shoulder bone study. [less ▲]

Detailed reference viewed: 57 (15 ULg)
Peer Reviewed
See detailAttenuation et artefacts en TEMP osseuse du bassin et des hanches reconstruite par MLEM
Seret, Alain ULg; Blocklet, Didier; Nuyts, Johan

in Médecine Nucléaire : Imagerie Fonctionnelle et Métabolique (2001), 25(10), 602

Detailed reference viewed: 38 (1 ULg)
Peer Reviewed
See detailImpact of a camera change in ventriculography
Seret, Alain ULg; Blocklet, Didier; Lisart, Jean et al

in European Journal of Nuclear Medicine (2000), 27

Detailed reference viewed: 27 (2 ULg)
See detailSpondylolyse bilatérale: intérêt de la tomoscintigraphie osseuse.
Blocklet, Didier; Seret, Alain ULg; Schoutens, André

in Revue Médicale de Bruxelles (2000), 21

Clinical case.

Detailed reference viewed: 257 (7 ULg)
Full Text
Peer Reviewed
See detailMaximum-likelihood reconstruction with ordered subsets in bone SPECT
Blocklet, Didier; Seret, Alain ULg; Popa, Niculaie et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1999), 40(12), 1978-1984

This study was aimed at determining whether the ordered-subset expectation maximum (OSEM) is more effective than filtered backprojection (FBP) for bone SPECT in the routine clinical context. Methods ... [more ▼]

This study was aimed at determining whether the ordered-subset expectation maximum (OSEM) is more effective than filtered backprojection (FBP) for bone SPECT in the routine clinical context. Methods. Fifty-seven consecutive bone SPECT studies were analyzed. They included pelvic and lumbar spine, thoraco lumbar spine, head and neck, feet and shoulders. A 64-projection SPECT study was acquired over 360° by single-head cameras 2–3h after the injection of 750 MBq 99mTc-methylene diphosphonate. Three observers compared the OSEM and FBP reconstructed images. Results. Streak artifacts, always present with FBP, were rarely generated with the OSEM. When present (n = 24), artifacts associated with negative values near hyperactivities in FBP were not generated with the OSEM in 67% of the cases (n = 16), permitting a satisfactory interpretation of these regions. In half of the other cases (17%, n = 4/24), interpretation was precluded. In only one case did the three observers agree that more hyperactivities were seen with the OSEM. Ninety-six percent of the OSEM pictures were superior or equal to FBP for anatomic resolution and were clearly better in 12% of the cases. The extent of the lesion with the OSEM seemed better or equally defined in 96% and clearly better in 14% of the cases. The low-activity regions were better or equally visualized in all cases and were clearly better seen in 23% of the cases. The quality of the pictures was found to be better or superior with the OSEM in 98% of the cases and definitely better in 65% of the cases. Conclusion: Replacement of FBP by the OSEM in bone SPECT would be beneficial to clinical practice. [less ▲]

Detailed reference viewed: 72 (5 ULg)
Peer Reviewed
See detailAdvantages of iterative OSEM reconstruction over filtered backprojection in bone SPET
Blocklet, Didier; Seret, Alain ULg; Popa, N. et al

in Journal of Nuclear Medicine : Official Publication, Society of Nuclear Medicine (1999, May), 40(5), 303

Detailed reference viewed: 114 (5 ULg)
See detailMedian root prior for DMSA cortical renal SPET
Seret, Alain ULg; Blocklet, Didier; Schoutens, André

in Tijdschrift voor Nucleaire Geneeskunde (1999), 21(3), 104

Detailed reference viewed: 14 (7 ULg)
Peer Reviewed
See detailMedian root prior for DMSA cortical renal SPET
Seret, Alain ULg; Blocklet, Didier; Schoutens, André

in European Journal of Nuclear Medicine (1999), 26

Detailed reference viewed: 18 (3 ULg)
See detailPinhole SPECT of small animals using vendor standard equipment.
Seret, Alain ULg; Schoutens, André; Blocklet, Didier et al

in Tijdschrift voor Nucleaire Geneeskunde (1999), 21(3), 103-104

Detailed reference viewed: 17 (1 ULg)
Full Text
Peer Reviewed
See detailHyperactivity in the low sternal region with Tc-99m sestamibi: possible cardiac origin
Servais, Fabienne; Seret, Alain ULg; Blocklet, Didier et al

in Clinical Nuclear Medicine (1998), 23(7), 461-462

Scintimammography performed with Tc-99m sestamibi in a 63-year-old woman with a history of mitral valve replacement and pulmonary hypertension demonstrated that the frequently observed sternal ... [more ▼]

Scintimammography performed with Tc-99m sestamibi in a 63-year-old woman with a history of mitral valve replacement and pulmonary hypertension demonstrated that the frequently observed sternal hyperactivity on anterior views could arise from the myocardium. Caution therefore should be taken before the diagnosing of any hyperactivity in the lower sternal region as a neoplastic involvement. [less ▲]

Detailed reference viewed: 38 (1 ULg)
See detailNéoplasie mammaire plurifocale en généralisation osseuse
Blocklet, Didier; Seret, Alain ULg; Schoutens, André

in Revue Médicale de Bruxelles (1998), 19

Clinical case.

Detailed reference viewed: 262 (0 ULg)
Full Text
Peer Reviewed
See detailDifferentiation between begnin and malignant breast lesions with MR imaging and scintimammography
Servais, Fabienne; Blocklet, Didier; Seret, Alain ULg et al

in Radiology (1997), 205(1), 283

No abstract for this letter.

Detailed reference viewed: 48 (1 ULg)