Tatsuya Kuramitsu

High resolution CT findings in community-acquired pneumonia

PURPOSE Our goal was to clarify the high resolution CT (HRCT) findings of community-acquired pneumonia based on pathologic findings and to make a differential diagnosis between bacterial and atypical pneumonias. METHOD This study evaluated 32 cases with community-acquired pneumonia, including 18 cases with bacterial pneumonia and 14 cases with atypical pneumonia [mycoplasma pneumonia (n = 12), chlamydia pneumonia (n = 1), and influenza viral pneumonia (n = 1)]. HRCT images in these cases were space consolidation, ground-glass attenuation, thickening of the bronchovascular bundle, and distribution of abnormal attenuation. RESULTS Bacterial pneumonia frequently showed air space consolidation with segmental distribution (72.2%) that tended to locate at the middle and outer zones of the lung. Atypical pneumonia frequently showed centrilobular shadow (64.3%), acinar shadow (71.4%), air space consolidation and ground-glass attenuation with lobular distribution (57.1 and 85.7%, respectively), and tendency of the lesions to distribute at the inner layer of the lung in addition to the middle and outer layers (85.7%). CONCLUSION Characteristic HRCT findings of both bacterial and atypical pneumonia were demonstrated. These HRCT features seemed to reflect pathologic findings and the manner of lesional progression. This information may support the appropriate antibiotic therapy in medical practice.

The role of Gallium-67 imaging in the detection of foci in recent cases of fever of unknown origin

We have assembled data from patients with fever of unknown origin who underwent gallium scintigraphy during the past 5 years in order to obtain a more current sampling of patients, and evaluated the role of gallium scintigraphy retrospectively. Of the 36 patients studied, gallium scintigraphy was positive and contributed to the detection of the foci or fever origins in 17 (47.2%). The ratio of neoplastic diseases with myeloproliferative and with lymphoproliferative disorders was relatively high compared with previous reports. However, gallium scintigraphy did not contribute to the diagnosis of collagen disease. With the ability to detect both inflammatory and neoplastic lesions, gallium scintigraphy was useful in detecting the foci of fevers of unknown origin.

Scintigraphic analysis of hemodynamics in a patient with a single large pulmonary arteriovenous fistula.

A pulmonary perfusion study was performed on a 54- year-old man with a single large pulmonary arteriovenous fistula (aneurysmal type) using Tc-99m MAA. On the static imaging, a defect corresponding to the location of the mass and right-to-left shunt was clearly documented. Decreased uptake of Tc-99m MAA in the lung field surrounding the lesion was observed and was thought to reflect a “steal” of blood flow by the fistula. One advantage of using radionuclide angiography with Tc-99m MAA rather than with Tc-99m pertechnetate was that it more easily provided a time-activity curve that added useful quantitative information about the altered pulmonary hemodynamics.

Thin-section oblique CT with 25° cranially tilted images Evaluation of pulmonary tumors adjacent to the interlobar fissures

Purpose: Thin-section oblique CT with cranially tilted axial scans can provide better visualization of the interlobar fissures than thin-section CT with conventional axial scans. the purpose of this study was to evaluate the usefulness of oblique CT scans for pulmonary tumors adjacent to the interlobar fissures. Material and Methods: Cranially tilted and conventional axial images were obtained by thin-section CT in 10 patients with solitary pulmonary tumors adjacent to the interlobar fissures. Conventional CT with a 2-mm collimation and thin-section oblique CT with a 25° cranial tilt were obtained. Results: the images obtained by thin-section oblique scanning visualized the relationship between the pulmonary tumor and the interlobar fissures in all 10 patients, whereas in 6 patients the thin-section conventional images did not. the pulmonary tumors in these 6 patients included all 5 that were adjacent to the minor fissures. Conclusion: Thin-section oblique CT may be more useful than thin-section conventional CT in evaluating the relationship between pulmonary tumors and the minor fissures.