European journal of nuclear medicine and molecular imaging
-
Eur. J. Nucl. Med. Mol. Imaging · Jul 2003
Comparative Study Clinical Trial Controlled Clinical TrialRole of ventilation scintigraphy in diagnosis of acute pulmonary embolism: an evaluation using artificial neural networks.
The purpose of this study was to assess the value of the ventilation study in the diagnosis of acute pulmonary embolism using a new automated method. Either perfusion scintigrams alone or two different combinations of ventilation/perfusion scintigrams were used as the only source of information regarding pulmonary embolism. A completely automated method based on computerised image processing and artificial neural networks was used for the interpretation. ⋯ The performance increased to 0.87 (0.81-0.93) when all perfusion and ventilation images were used, and the increase in performance from 0.79 to 0.87 was also statistically significant ( P=0.016). The automated method presented here for the interpretation of lung scintigrams shows a significant increase in performance when one or all ventilation images are added to the six perfusion images. Thus, the ventilation study has a significant role in the diagnosis of acute lung embolism.
-
Eur. J. Nucl. Med. Mol. Imaging · Jul 2003
Comparative Study Clinical Trial Controlled Clinical TrialValidation of the dual-table autoradiographic method to quantify two sequential rCBFs in a single SPET session with N-isopropyl-[123I] p-iodoamphetamine.
We evaluated an autoradiographic (ARG) method to calculate regional cerebral blood flow (rCBF) sequentially before and after an acetazolamide (ACZ) challenge in a single session of single-photon emission tomography (SPET) with two injections of N-isopropyl-[(123)I] p-iodoamphetamine (IMP). The method uses a table look-up method with a fixed distribution volume (Vd) and a standard input function of IMP. To calculate rCBF after an ACZ challenge, two look-up tables (a dual-table) are used to reflect the effect of radioactivity in the brain from the first dose of IMP. ⋯ In the patient study with a proposed scan protocol of 25 min for the first and 15 min for the second measurement, the error attributable to the standard input function was smaller when calibrated with a continuously drawn arterial blood sample (random error of 3.8% for continuous 10-min arterial blood sampling after the second dose of IMP) than with a single arterial blood sample (random error of 9.0% at 5 min after the second dose of IMP). Systematic and random errors of F(SIF) compared with F(REF) were 0.0% and 6.3%, respectively. The dual-table ARG method can be reliably used to quantify rCBF before and after an ACZ challenge with a 40-min scan protocol and continuous arterial blood sampling for several minutes.
-
Eur. J. Nucl. Med. Mol. Imaging · Jul 2003
Comparative Study Clinical Trial[18F]FDG imaging of head and neck tumours: comparison of hybrid PET and morphological methods.
The aim of this study was to evaluate fluorine-18 fluorodeoxyglucose ([(18)F]FDG) imaging of head and neck tumours using a second- or third-generation hybrid PET device. Results were compared with the findings of spiral computed tomography (CT) and magnetic resonance imaging (MRI), and, as regards lymph node metastasis, the ultrasound findings. A total of 116 patients with head and neck tumours (83 males and 33 females aged 27-88 years) were examined using a hybrid PET scanner after injection of 185-350 MBq of [(18)F]FDG (Picker Prism 2000 XP-PCD, Marconi Axis gamma-PET(2) AZ). ⋯ In one patient, unrecognised metastatic lesions were seen on hybrid PET elsewhere in the body (lung: n=1; bone: n=1). Additional malignant lesions at sites other than the head and neck tumour were found in three patients (one patient with lung cancer, one patient with pelvic metastasis due to a carcinoma of the prostate and one patient with pulmonary metastasis due to breast cancer). It is concluded that [(18)F]FDG PET with hybrid PET scanners is superior to CT and MRI in the diagnosis of primary or recurrent lesions as well as in the assessment of lymph node involvement, whereas it is inferior to ultrasound in the detection of cervical lymph node metastasis.
-
Eur. J. Nucl. Med. Mol. Imaging · Jul 2003
Clinical TrialPreoperative mapping of cortical language areas in adult brain tumour patients using PET and individual non-normalised SPM analyses.
In patients scheduled for the resection of perisylvian brain tumours, knowledge of the cortical topography of language functions is crucial in order to avoid neurological deficits. We investigated the applicability of statistical parametric mapping (SPM) without stereotactic normalisation for individual preoperative language function brain mapping using positron emission tomography (PET). Seven right-handed adult patients with left-sided brain tumours (six frontal and one temporal) underwent 12 oxygen-15 labelled water PET scans during overt verb generation and rest. ⋯ An SPM group analysis ( P<0.05, corrected) in patients with left frontal tumours confirmed the activation pattern shown by the individual analyses. We conclude that SPM analyses without stereotactic normalisation offer a promising alternative for analysing individual preoperative language function brain mapping studies. The observed right frontal activations agree with proposed reorganisation processes, but they may also reflect an unspecific recruitment of the right-sided Broca's homologue in the effort to perform the task.