Influence of slice overlap on positron emission tomography image quality.

PET scans use overlapping acquisition beds to correct for reduced sensitivity at bed edges. The optimum overlap size for the General Electric (GE) Discovery 690 has not been established. This study assesses how image quality is affected by slice overlap.

PET-CT evaluation of solitary pulmonary nodules: correlation with maximum standardized uptake value and pathology.

Purpose: 18-fluorine fluorodeoxyglucose ((18)F-FDG) positron emission tomography-computed tomography (PET-CT) has an established role for the characterization of solitary pulmonary nodules (SPN). Visual assessment of nodule morphology, together with maximum standardized uptake value (SUVmax), is used to estimate likelihood of malignancy. We correlated SUVmax value with pathology of SPN and assessed diagnostic accuracy in differentiating malignant from benign nodule, using 2.

5-(123)I-A-85380 binding to the α4β2-nicotinic receptor in mild cognitive impairment.

Treatments currently licensed for Alzheimer's dementia target cholinergic brain systems. In vivo nicotinic receptor binding may provide an early marker of illness and treatment suitability. In this pilot, we examined nine patients with amnestic mild cognitive impairment (MCI) and 10 age and education matched healthy volunteers with high resolution SPECT and the nicotinic receptor ligand 5-(123)I-A-85380.

Assessment of 123I-FIAU imaging of herpes simplex viral gene expression in the treatment of glioma.

Background: Herpes simplex virus 1716 (HSV1716), a selectively replication competent mutant of HSV1, is under investigation as an oncolytic viral therapy in human malignant glioma. As with similar therapies, a technique for measurement of viral replication and distribution over time following virus administration is required. Imaging expression of the HSV-thymidine kinase (HSV-tk) gene offers an opportunity for non-invasive assessment of viral distribution in living subjects.

Serotonin transporter residual availability during long-term antidepressant therapy does not differentiate responder and nonresponder unipolar patients.

Background: Serotonin transporters (SERT) are a major target for antidepressant medication, although there have been limited in vivo studies of SERT availability in patients being treated with antidepressants. It is not known whether SERT availability differs in treatment-responsive and -nonresponsive patients receiving long-term treatment. In this study, we used single photon emission computed tomography (SPECT) to compare SERT residual availability in unipolar responders and nonresponders during long-term antidepressant treatment.

Measurement of tumor "size" in recurrent malignant glioma: 1D, 2D, or 3D?

Background And Purpose: Tumor "size" is used internationally as a surrogate marker for overall survival when following current response assessment protocols (World Health Organization and Response Evaluation Criteria in Solid Tumors). With little evidence of a relationship between tumor "size" and survival in intrinsic brain tumors, this study was undertaken to investigate the predictive value of MR imaging-defined tumor size for survival in patients with recurrent malignant glioma and to compare the different measures of tumor size used in these current response assessment protocols.

Methods: Volumetric, bidimensional, and unidimensional measurements of tumor size were made using baseline contrast-enhanced T1-weighted images of 70 patients with recurrent malignant glioma receiving intravenous chemotherapy.

MRI safety review.

Magnetic resonance is an extremely powerful imaging tool which does not expose patients to ionizing radiation. However, there are risks associated with the MR environment which all staff must be aware of and eliminate. The aim of this article is to highlight the well known and not so well known potentially adverse interactions.

Self-stunning in thyroid ablation: evidence from comparative studies of diagnostic 131I and 123I.

Twenty-six patients who had undergone recent surgery for differentiated thyroid cancer were investigated using iodine-131 iodide (120 MBq). Uptake in the thyroid bed was measured at 3 days using a dual-head gamma camera. An ablation activity of 131I iodide (4,000 MBq) was administered 3-38 (median 14) days later and uptake in the thyroid bed measured once or twice, 1-3 days post therapy.