BackgroundPheochromocytomas (PCC) and paragangliomas (PGL) are neuroendocrine tumours arising from pluripotent neural crest stem cells and are associated with neurons of the autonomic nervous system. PCCs/PGLs are often hereditary and multifocal, and their biologic behaviour and metabolic activity vary making imaging of these tumours challenging. The imaging gold standard has been I-123 MIBG complemented by CT or MRI. PGLs being neuroendocrine tumours express somatostatin receptors enabling imaging with Ga-68 DOTA-coupled peptides such as DOTATATE. Imaging with F-18 FDG also provides additional information regarding metabolic activity and biologic aggressiveness of these tumours, or, in some situations, reflecting metabolic reprogramming of these tumours. We report our experience using both Ga-68 DOTATATE and F-18 FDG PET/CT imaging in patients with PGLs and PCCs.MethodsThis was a retrospective review of 23 patients with proven PGL/PCC who underwent both DOTATATE and FDG PET/CT. Seven patients also had I-123 MIBG SPECT/CT and 1 patient had I-124 MIBG PET/CT. Lesional intensity and patterns of uptake were analysed.ResultsDOTATATE and FDG were positive at most sites of disease (96.2 % vs 91.4 %), although uptake intensity was significantly higher on DOTATATE with a median SUV of 21 compared to 12.5 for FDG (p < 0.001). SUVmax on F-18 FDG was significantly higher (p < 0.001) in clinically aggressive cases. I-123/I-124 MIBG detected fewer lesions (30.4 %).ConclusionOverall, Ga-68 DOTATATE PET/CT detected similar number but has significantly greater lesion-to-background contrast compared to F-18 FDG PET/CT. Combined with high specificity, patient convenience and relatively low cost, DOTATATE PET/CT should be considered the ideal first line investigation for imaging PGL/PCC. Depending on DOTATATE findings and the clinical question, FDG and MIBG remain useful and, in selected cases, may provide more accurate staging, disease characterisation and guide treatment choices.

The purpose of this study is to ascertain the error rates of using a voice recognition (VR) dictation system. We compared our results with several other articles and discussed the pros and cons of using such a system. The study was performed at the Southern Health Department of Diagnostic Imaging, Melbourne, Victoria using the GE RIS with Powerscribe 3.5 VR system. Fifty random finalized reports from 19 radiologists obtained between June 2008 and November 2008 were scrutinized for errors in six categories namely, wrong word substitution, deletion, punctuation, other, and nonsense phrase. Reports were also divided into two categories: computer radiography (CR= plain film) and non-CR (ultrasound, computed tomography, magnetic resonance imaging, nuclear medicine, and angiographic examinations). Errors were divided into two categories, significant but not likely to alter patient management and very significant with the meaning of the report affected, thus potentially affecting patient management (nonsense phrase). Three hundred seventy-nine finalized CR reports and 631 non-CR finalized reports were examined. Eleven percent of the reports in the CR group had errors. Two percent of these reports contained nonsense phrases. Thirty-six percent of the reports in the non-CR group had errors and out of these, 5% contained nonsense phrases. VR dictation system is like a doubleedged sword. Whilst there are many benefits, there are also many pitfalls. We hope that raising the awareness of the error rates will help in our efforts to reduce error rates and strike a balance between quality and speed of reports generated.

Progressive transformation of the germinal centers (PTGC) is a benign reaction pattern in lymph nodes. An association with Hodgkin disease (HD) has been reported and PTGC may precede, coexist, or present after the diagnosis of HD.This case report describes a patient who presented with unprovoked pulmonary embolism and subsequent investigations showed a solitary abdominal mass, which was subsequently proven to be PTGC. PTGC is usually avid on fluorine-18-labeled fluorodeoxyglucose positron emission tomography with computed tomography for attenuation correction and may be mistaken for neoplastic disease. Being a reactive etiology, the metabolic activity is generally low with a low maximum standardized uptake value (SUVmax), but in our case, the metabolic activity and corresponding SUVmax were relatively high making the diagnosis difficult, as most clinicians would consider a high metabolically active process more likely malignant.Recognition of PTGC is important, as it is not a malignant process. Owing to its reported associations, however, patients with this diagnosis will likely require regular surveillance.