ABSTRACT
Positron emission tomography (PET) scanning with [18F] fluorodeoxyglucose (FDG) has developed over 25 years into a valuable clinical tool used mainly for the evaluation of oncology patients. The purpose of this article is to provide an introduction to the basic scientific concepts of FDG-PET imaging as well as to illustrate its clinical utility.
Subject(s)
Fluorodeoxyglucose F18 , Radiopharmaceuticals , Tomography, Emission-Computed , Adenocarcinoma/diagnostic imaging , Adult , Aged , Aged, 80 and over , Carcinoma, Bronchogenic/diagnostic imaging , Colonic Neoplasms/diagnostic imaging , Female , Hodgkin Disease/diagnostic imaging , Humans , Lung Neoplasms/diagnostic imaging , Male , Middle AgedABSTRACT
Differentiating thymic rebound from recurrent tumor may be difficult in pediatric patients following chemotherapy for Hodgkin's disease. We present a patient who had both a negative 67Ga scan and computed tomography (CT) of the chest at diagnosis and demonstrated gallium avidity and CT evidence of a new mediastinal mass at the completion of chemotherapy. There was, however, no other clinical or laboratory evidence of disease recurrence. Thallium-201 imaging was subsequently performed and demonstrated no significant radionuclide accumulation within this anterior mediastinal mass. CT shows only the presence of a mass, but not it's nature. Gallium-67 scintigraphy, while used widely as an indicator of tumor viability, may demonstrate increased uptake in cases of thymic rebound. Thallium-201 imaging has previously been shown to demonstrate increased uptake in mediastinal malignancy. Conversely, no significant mediastinal uptake of 201Tl, as in this case, provides additional supportive evidence for a benign mediastinal entity such as thymic rebound.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Gallium Radioisotopes , Hodgkin Disease/drug therapy , Mediastinal Neoplasms/etiology , Neoplasm Recurrence, Local/diagnostic imaging , Thallium Radioisotopes , Thymus Hyperplasia/diagnostic imaging , Child, Preschool , Diagnosis, Differential , Hodgkin Disease/diagnostic imaging , Humans , Male , Mediastinal Neoplasms/diagnostic imaging , Radionuclide Imaging , Tomography, X-Ray ComputedABSTRACT
Tracheal bronchus is an uncommon anomaly of the tracheobronchial tree. In the case presented, clinical and pathophysiologic abnormalities were associated with this anomaly. The tracheal bronchus supplied the right upper lobe of the lung. The bronchus intermedius arose directly from the trachea in place of the right main bronchus. It was accompanied by marked regional changes in ventilation and perfusion. We discuss the clinical significance of this unusual anomaly.
Subject(s)
Bronchi/abnormalities , Lung/diagnostic imaging , Respiration , Trachea/abnormalities , Aged , Humans , Male , Radiography , Radionuclide Imaging , Respiratory Function TestsABSTRACT
A technique for stochastic analysis of 133Xe washout using a computer-assisted Anger camera is described. The technique produces functional maps of both regional cerebral blood flow (rCBF) and error in rCBF. The calculational limitations of the technique are discussed and an experimental estimate made of the physical limitations associated with the low energy photon emitted by 133Xe. The method is demonstrated in a rhesus monkey model before and after surgical occlusion of the middle cerebral artery.
