CT-based SPECT attenuation correction and assessment of infarct size: results from a cardiac phantom study.

Rationale: Myocardial perfusion SPECT is a commonly performed, well established, clinically useful procedure for the management of patients with coronary artery disease. However, the attenuation of photons from myocardium impacts the quantification of infarct sizes. CT-Attenuation Correction (AC) potentially resolves this problem.

WWSSF - a worldwide study on radioisotopic renal split function: reproducibility of renal split function assessment in children.

Purpose: The split or differential renal function is the most widely accepted quantitative parameter derived from radionuclide renography. To examine the intercenter variance of this parameter, we designed a worldwide round robin test.

Methods: Five selected dynamic renal studies have been distributed all over the world by e-mail.

Multiparametric PET imaging in thyroid malignancy characterizing tumour heterogeneity: somatostatin receptors and glucose metabolism.

Purpose: Radiolabelled somatostatin (SST) analogues have proven useful in diagnosing tumours positive for SST receptor (SSTR). As different subtypes of SSTR are expressed on the tumour cell surface, the choice of appropriate therapeutic SST analogue is crucial. We evaluated the SSTR status of thyroid cancer patients who had signs of progressive disease comparing different SSTR ligands for PET imaging to evaluate possible further therapeutic options.

Stereotactic radiofrequency ablation of unresectable intrahepatic cholangiocarcinomas: a retrospective study.

Purpose: To evaluate treatment effects, complications, and outcome of percutaneous stereotactic radiofrequency ablation (SRFA) of intrahepatic cholangiocarcinoma (ICC).

Patients And Methods: Eleven consecutive patients (nine men and two women) with a total of 36 inoperable ICCs (18 initial lesions, 16 lesions newly detected during follow-up, and two local recurrences) underwent SRFA between December 2004 and June 2010. Two different radiofrequency ablation (RFA) devices with internally cooled electrodes were used.

PET based volume segmentation with emphasis on the iterative TrueX algorithm.

Purpose: To assess the influence of reconstruction algorithms for positron emission tomography (PET) based volume quantification. The specifically detected activity in the threshold defined volume was investigated for different reconstruction algorithms as a function of volume size and signal to background ratio (SBR), especially for volumes smaller than 1ml. Special attention was given to the Siemens specific iterative reconstruction algorithm TrueX.

68Ga-siderophores for PET imaging of invasive pulmonary aspergillosis: proof of principle.

Unlabelled: The diagnosis of invasive pulmonary aspergillosis (IPA) is difficult and lacks specificity and sensitivity. In the pathophysiology of Aspergillus fumigatus, iron plays an essential role as a nutrient during infection. A.

Preliminary experience with (68)Ga-DOTA-lanreotide positron emission tomography.

Aim: Positron emission tomography (PET) of (68)Ga-radiolabelled (SST) somatostatin receptor (R) binding peptides has recently been evaluated in SSTR positive tumor patients. First promising results in lung and thyroid tumor patients with (111)In-DOTA-Lanreotide (DOTA-LAN) scintigraphy have been described. We report our first experience with (68)Ga-labeled DOTA-LAN.

Response of recurrent high-grade glioma to treatment with (90)Y-DOTATOC.

Unlabelled: The treatment of patients with high-grade malignant glioma still represents an unsolved clinical problem. We report the treatment of 3 patients who had World Health Organization grade IV recurrent glioblastoma: a 23-y-old woman and 2 men aged 61 and 62 y.

Methods: All 3 patients were treated with the somatostatin receptor radiopharmaceutical (90)Y-labeled [1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid(0)-d-Phe(1),Tyr(3)]octreotide (DOTATOC).

Radiolabeling of lipid-based nanoparticles for diagnostics and therapeutic applications: a comparison using different radiometals.

Radiolabeling of nanoparticles (NPs) has been performed for a variety of reasons, such as for studying pharmacokinetics, for imaging, or for therapy. Here, we describe the in vitro and in vivo evaluation of DTPA-derivatized lipid-based NP (DTPA-NP) radiolabeled with different radiometals, including (111)In and (99m)Tc, for single-photon emission computed tomography (SPECT), (68)Ga for positron emission tomography (PET), and (177)Lu for therapeutic applications. PEGylated DTPA-NP with varying DTPA amounts, different composition, and size were radiolabeled with (111)In, (177)Lu, and (68)Ga, using various buffers.

68Ga-DOTA-Tyr3-octreotide PET for assessing response to somatostatin-receptor-mediated radionuclide therapy.

Unlabelled: (68)Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-d-Phe(1)-Tyr(3)-octreotide (DOTA-TOC) PET has proven its usefulness in the diagnosis of patients with neuroendocrine tumors. Radionuclide therapy ((90)Y-DOTA-TOC or (177)Lu-DOTA-octreotate) is a choice of treatment that also requires an accurate diagnostic modality for early evaluation of treatment response. Our study compared (68)Ga-DOTA-TOC PET with CT or MRI using the Response Evaluation Criteria in Solid Tumors.

Bone metastases in patients with neuroendocrine tumor: 68Ga-DOTA-Tyr3-octreotide PET in comparison to CT and bone scintigraphy.

Unlabelled: Somatostatin receptor scintigraphy is an accurate imaging modality for the diagnosis of neuroendocrine tumor. Because detection of distant metastases has a major impact on treatment, early diagnosis of metastatic spread is of great importance. So far, no standard procedure has become established for the early diagnosis of bone metastases from neuroendocrine tumor.

68Ga-DOTA-Tyr3-octreotide PET in neuroendocrine tumors: comparison with somatostatin receptor scintigraphy and CT.

Unlabelled: The aim of this study was to evaluate the diagnostic value of a new somatostatin analog, (68)Ga-labeled 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-d-Phe(1)-Tyr(3)-octreotide ((68)Ga-DOTA-TOC), for PET in patients with known or suspected neuroendocrine tumors. PET was compared with conventional scintigraphy and dedicated CT.

Methods: Eighty-four patients (48 men, 36 women; age range, 28-79 y; mean age +/- SD, 58.

FDG gamma camera PET equipped with one inch crystal and XCT. Assessment of myocardial viability.

Unlabelled: Metabolic imaging with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) is actually considered as the best method to detect and quantitatively assess myocardial tissue viability. The aim of this study was to investigate the accuracy of FDG gamma camera positron emission tomography (GCPET) imaging equipped with one inch NaI crystals in comparison to FDG dedicated PET (dPET) imaging as a "gold standard" in phantom and clinical studies.

Patients, Methods: Nineteen patients with coronary artery disease (CAD) underwent both imaging modalities.

[Evaluation of the performance of a gamma camera equipped with a 5/8" versus 1" thick NaI detector].

The upgrade of a gamma camera from a 5/8" to a 1" thick crystal, the latter with StarBrite technology, prompted to the investigation of changes in performance parameters for planar scintigraphy and SPECT as well as for PET in coincidence mode. For planar and SPECT parameters, the performance was measured according to NEMA Standard Protocol NU1-2001. No changes were found in terms of intrinsic uniformity, intrinsic spatial resolution, linearity, energy resolution, system resolution, and tomographic system resolution.

11C-acetate positron emission tomography imaging and image fusion with computed tomography and magnetic resonance imaging in patients with recurrent prostate cancer.

Purpose: To assess the clinical value of computed tomography (CT) and magnetic resonance imaging (MRI) image fusion with 11C-acetate (AC) positron emission tomography (PET) imaging for detection and exact location of clinically occult recurrences.

Patients And Methods: Fifty prostate cancer patients with elevated/increasing serum prostate-specific antigen levels after radical therapy underwent whole-body AC PET. Uptake was initially interpreted as normal, abnormal, or equivocal.

Combined PET and microdialysis for in vivo assessment of intracellular drug pharmacokinetics in humans.

Unlabelled: Because many drugs possess an intracellular site of action, the knowledge of intracellular concentration-time profiles is desirable. In the present study, PET, which measures total (i.e.

Influence of functional haplotypes in the drug transporter gene ABCB1 on central nervous system drug distribution in humans.

Background And Objective: Single nucleotide polymorphisms in the human multidrug-resistance gene ABCB1 have been reported to be associated with altered expression and function of P-glycoprotein, an efflux transporter, expressed at the blood-brain barrier. To test whether certain ABCB1 haplotypes contribute to interindividual differences in central nervous system drug distribution, brain distribution of a model P-glycoprotein substrate, the calcium channel inhibitor verapamil, was measured by positron emission tomography (PET) in 2 groups of healthy volunteers.

Methods: Ten homozygous carriers (cases) of the TTT haplotype (3435T, 1236T, and 2677T) and 10 controls homozygous for the wild-type CGC haplotype (3435C, 2677G, and 1236C) were administered a mean intravenous bolus of 412 +/- 114 MBq carbon 11-labeled verapamil containing less than 15 nmol of unlabeled verapamil.

An inter-laboratory comparison study of image quality of PET scanners using the NEMA NU 2-2001 procedure for assessment of image quality.

An inter-laboratory comparison study was conducted to assess the image quality of PET scanners in Austria. The survey included both dedicated PET scanners (D-PET, n = 8) and coincidence cameras (GC-PET, n = 7). Measurement of image quality was based on the NEMA (National Electrical Manufacturers Association) NU 2-2001 protocol and the IEC (International Electrotechnical Commission) body phantom.

In vitro and in vivo evaluation of [18F]ciprofloxacin for the imaging of bacterial infections with PET.

Purpose: The suitability of the 18F-labelled fluoroquinolone antibiotic ciprofloxacin ([18F]ciprofloxacin) for imaging of bacterial infections with positron emission tomography (PET) was assessed in vitro and in vivo.

Methods: For the in vitro experiments, suspensions of various E. coli strains were incubated with different concentrations of [18F]ciprofloxacin (0.

[Hybrid imaging for endocrine diseases: new perspectives].

Hybrid Imaging, also termed dual modality imaging, is the technique of fusionizing and interpreting images, that are gained from two different modalities constructed in one unit. Therefore, hybrid imaging may be regarded as a form of image fusion. Clinical applications in the field of endocrinology are the localization of neuroendocrine tumors and of lesions of the adrenal or the parathyroid glands.

Value of combined XCT/SPECT technology for avoiding false positive planar (123)I-MIBG scintigraphy.

Aim: The clinical value of combined XCT/SPECT technology in a single device in patients undergoing (123)I-MIBG scintigraphy was analyzed.

Methods: 31 patients (19 men, 12 women; mean age 55 years, range: 31-79 years) demonstrating focal accumulation in planar (123)I-MIBG scan were further investigated with a double headed gamma camera with an X-ray tomograph mounted on the same gantry (GE Medical Systems, Millennium VG with Hawkeye, Milwaukee, USA) for anatomical definition of the focal (123)I-MIBG uptake. The patients were referred to (123)I-MIBG scintigraphy because of biochemically (81%) and/or clinically (19%) suspected pheochromocytoma.

[18F]Ciprofloxacin, a new positron emission tomography tracer for noninvasive assessment of the tissue distribution and pharmacokinetics of ciprofloxacin in humans.

The biodistribution and pharmacokinetics of the fluorine-18-labeled fluoroquinolone antibiotic [(18)F]ciprofloxacin in tissue were studied noninvasively in humans by means of positron emission tomography (PET). Special attention was paid to characterizing the distribution of [(18)F]ciprofloxacin to select target tissues. Healthy volunteers (n = 12) were orally pretreated for 5 days with therapeutic doses of unlabeled ciprofloxacin.