A recovery coefficient method for partial volume correction of PET images.

Objectives: Correction of the "partial volume effect" has been an area of great interest in the recent times in quantitative PET imaging and has been mainly studied with count recovery models based upon phantoms that incorporate hot spheres in a cold background. The goal of this research study was to establish a similar model that is closer to a biological imaging environment, namely hot spheres/lesions in a warm background and to apply this model in a small cohort of patients.

Methods: A NEMA phantom with six spheres (diameters 1-3.

Follow-up FDG PET in the evaluation of unexplained focal activity in the abdomen.

Purpose: This study assessed the value of a follow-up FDG PET scan when the initial PET demonstrated unexplained findings of focal FDG uptake in the abdomen.

Method: The records of 3634 patients with PET scans were retrospectively reviewed. Those patients who had follow-up PET scans after the initial PET scan showed unexplained FDG activity in the abdomen were further analyzed.

Dual-time point FDG PET imaging in the evaluation of pulmonary nodules with minimally increased metabolic activity.

Purpose: FDG PET has high accuracy in the evaluation of lung nodules. A standardized uptake value (SUV) > or =2.5 is frequently used as a criterion for malignancy in this setting.

Metachronous, multicentric giant cell tumor of the sphenoid bone with histologic, CT, MR imaging, and positron-emission tomography/CT correlation.

Giant cell tumor (GCT) of the sphenoid bone is a relatively rare entity and metachronous multicentric GCT of the sphenoid is even rarer; we are aware of only 3 previous cases in the literature. We describe here a tumor of the sphenoid bone that was identified 15 years after multiple resections of a GCT of the left inferior pubic ramus. Correlation is made between the histopathologic findings, MR imaging of the brain, CT of the head, and fusion positron-emission tomography (PET)/CT scan performed with fluorine-18 fluoro-2-deoxy-D-glucose (18F-FDG).

Intense esophageal FDG activity caused by Candida infection obscured the concurrent primary esophageal cancer on PET imaging.

Esophageal cancer frequently causes a focal intense FDG uptake on positron emission tomography (PET) imaging while esophagitis often results in a mild to moderate degree of FDG activity in a diffuse pattern. However, detection of an esophageal cancer can become difficult in the presence of a diffuse esophageal activity because of esophagitis. We present such case in which esophageal cancer superimposed by Candidal esophagitis is difficult to recognize on FDG PET images.