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G Todo

Publications and source records attributed to G Todo.

36 records · Page 2Linked to original sources
PubMed1986

Ventilation imaging with positron emission tomography and nitrogen 13.

Ventilation imaging using positron emission tomography (PET) and highly insoluble nitrogen 13 (N-13) was performed in one healthy volunteer and ten patients. These PET studies showed the three-dimensional distribution of ventilation abnormalities, such as peripheral air trapping, which xenon 133 studies had not revealed. Therefore, PET with N-13 may help elucidate more precisely the distribution and nature of ventilation abnormalities in various diseases.

Humans↗
PubMed1986

Stripe sign in pulmonary perfusion scintigraphy: central pattern of pulmonary emphysema. Work in progress.

Morphologic changes and ventilation abnormalities in the lung that resulted in the peripheral perfusion stripe (the stripe sign) on pulmonary perfusion scintigrams were studied in six patients. Chest radiographs, computed tomography (CT) scans, and positron emission tomography (PET) scans obtained using N-13 were compared. Although there was no apparent correlation between the presence of the stripe sign and the findings on the chest radiographs, PET scans depicted ventilation abnormalities in all of 11 lung areas with the stripe sign in six patients. In addition, ventilation was affected more severely in the central part of the lung than in the subpleural region in ten of the 11 lung areas. CT scans demonstrated emphysematous changes, with low attenuation values located mainly in the central part of the lung in all four patients examined. The results suggest an intimate relationship between the stripe sign and the central pattern of pulmonary emphysema.

Aged↗
PubMed1986

Centrilobular lesions of the lung: demonstration by high-resolution CT and pathologic correlation.

To determine the value of high-resolution computed tomography (HRCT) in the diagnosis of diffuse pulmonary diseases, a direct HRCT-pathologic correlative study was performed using four inflated and fixed lungs from autopsy. In normal lungs, the smallest pulmonary artery resolved by HRCT was 200 microns in diameter; the artery was accompanied by the terminal bronchiole and the first-order respiratory bronchiole. The distance from the vessel to the corresponding lobular border ranged from 3 to 5 mm. These results suggest that the centrilobular area or the area around the terminal or respiratory bronchioles can be recognized with HRCT. In addition, the authors confirmed that centrilobular emphysema and centrilobular tuberculous nodules can be diagnosed with HRCT. Thus, HRCT can demonstrate the location of pathologic changes within a lobule and may be helpful in the differential diagnosis of diffuse pulmonary diseases.

Humans↗
PubMed1983

Pulmonary blood flow distribution measured by radionuclide-computed tomography.

Distributions of pulmonary blood flow per unit lung volume were measured with subjects in the prone, supine, and sitting positions by means of radionuclide-computed tomography of intravenously administered 99mTc-labeled macroaggregates of human serum albumin. The blood flow was greater in the direction of gravity in all 31 subjects except one with severe mitral valve stenosis. With the subject in a sitting position, four different types of distribution were distinguished. One type had a three-zonal blood flow distribution as previously reported by West and co-workers (J. Appl. Physiol. 19: 713-724, 1964). Pulmonary arterial pressure and venous pressure estimated from this model showed reasonable agreement with pulmonary arterial pressure and capillary wedge pressure measured by Swan-Ganz catheter in 17 supine patients and in 2 sitting patients. The method makes possible noninvasive assessment of pulmonary vascular pressures.

Adult↗
PubMed1981

Determination of the pleural edge by gamma-ray transmission computed tomography.

A technique is described for transaxial imaging of the thorax during pulmonary perfusion study. The contours of the air-containing lungs were obtained by gamma-ray transmission data from a Tc-99m plane flood source. These images were overlaid on the emission tomogram of the pulmonary blood flow obtained with Tc-99m MAA. It permits reliable detection of peripheral perfusion defects. Use of the results from these measurements can be applied to evaluate marginal hypoperfusions of the lungs.

Adult↗
PubMedDate not supplied

Sclerosing stromal tumor of the ovary: MRI.

The MR and pathologic findings of a case of sclerosing stromal tumor (SST) are presented. MR findings reflecting pathological features of SST include pseudolobulation, which consists of low-intensity nodules set against high-intensity stroma on T2-weighted images, and striking enhancement on postcontrast images.

Adult↗