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.

[High-resolution MR imaging of the mediastinum and hilus of the lung using surface-coils].

High-resolution MR imaging using surface-coils (Helmholtz-coil) was performed on patients with hilar lung cancer and healthy volunteers. We evaluated the clinical usefulness of this technique compared with MR imaging performed with a conventional body-coil. Although the signal-to-noise ratio was slightly decreased, normal anatomic structures, hilar masses, and enlarged lymph nodes were distinctly visualized in comparison with those on MR images obtained with a body-coil. High-resolution MR imaging with the Helmholtz-coil seemed to be useful for the evaluation of mediastinal and hilar disease, and may able to supplant MR imaging with a conventional body-coil in routine examinations.

Imaging of the portacaval space.

The portacaval space is a relatively narrow region between the portal vein and the inferior vena cava that is usually well seen on cross-sectional abdominal imaging studies [1]. Various structures, including normal anatomic variants and extension of diseases from adjacent organs, can be detected within this space [1-3]. An awareness of the types of normal and abnormal structures can prevent misinterpretation and aid in evaluating the spread of malignant diseases. We describe the appearances of these entities within the portacaval space on several types of images.

[Usefulness of 2D FLASH multislice dynamic MR imaging for evaluation of parametrial invasion in cervical carcinoma].

Twenty seconds and 3 minutes after starting rapid injection of Gd-DTPA, multislice dynamic (MD) images were obtained with the 2 dimension fast low-angle shot (2D FLASH) technique. Four of 5 cervical carcinomas showed high signal intensity in the early dynamic phase (20 seconds), so they were readily distinguished from the myometrium that were not enhanced in the same phase. For evaluation of parametrial invasion, MD study showed better contrast between the tumor and the parametrium than did T2-weighted images because the tumor demonstrated a high signal intensity similar to that of the parameterium on T2-weighted images. MD images were able to scan the entire tumor especially in progressive cases and to evaluate the hemodynamics of the tumor. Therefore, MD imaging seemed to be useful for evaluation of parametrial invasion in cervical carcinomas.

[Evaluation of early MR imaging of the liver in rabbits after ethanol injection].

Seven days after ethanol injection, MR images of the liver in 5 rabbits were evaluated by T1, T2-weighted SE and TURBO-FLASH dynamic images. Necrotic area was visualized as low-intensity on T1-weighted images and high-intensity on T2-weighted images. These findings were similar to the tumor that was not treated, so it is necessary to be careful for evaluation of therapeutic efficacy. Necrotic area was not meanwhile enhanced on TURBO-FLASH dynamic images, therefore, dynamic study seemed to be useful for therapeutic efficacy after ethanol injection.

[Abnormal chest shadow on CT in immunosuppressed patients].

An abnormal chest shadow was observed on CT scans in 25 cases of 23 immunosuppressed patients. Pulmonary disease was pathologically confirmed to be pneumocystis carinii pneumonia (PC pneumonia) in four patients, cytomegalovirus pneumonia (CMV pneumonia) in one, bacterial pneumonia in seven, fungal infection in three, miliary tuberculosis in one, leukemic infiltration in two, lymphangitis carcinomatosa in three, drug-induced pneumonitis in three, and ARDS in one. In almost all patients, especially those with infectious diseases such as PC pneumonia, CMV pneumonia, and bacterial pneumonia, the abnormal shadow was wide and visible in the bilateral lung fields. We presumed that such findings as lobular shadow, centrilobular shadow, and mosaic pattern reflected the extension of disease via the respiratory tract, and that those findings are typical of infectious diseases. Because such findings as abnormal linear shadow and swelling of a broncho-vascular bundle were very frequently recognized in patients with lymphangitis carcinomatosa and frequently recognized in those with drug-induced pneumonitis, these diseases may be distinguished from other diseases. An area of slightly increased density was frequently recognized in patients with PC pneumonia, bacterial pneumonia, and drug-induced pneumonitis. Such lesions were pathologically confirmed to be located in the interstitium and/or alveolus. CT was extremely useful in comprehending the character and extension of particular diseases among various diseases. As the number of patients studied was small, the utility of CT in immunosuppressed patients requires further investigation in a larger number of patients.

[2D time of flight stereoscopic MR angiography of pulmonary vessels].

Two-dimensional (2D) time-of-flight (TOF) stereoscopic MR angiographies (MRA) of the pulmonary vessels were obtained from 15 healthy volunteers and five patients with pulmonary cancer in the mediastinum and pulmonary hilum. Fifteen healthy volunteers were examined using FLASH (Fast Low Angle Shot) with breath holding (40/8/40, TR/TE/flip angle). Except for the left superior pulmonary vein, pulmonary vessels in the mediastinum and hilum were well defined on stereoscopic MRA images. Although it was difficult to define the pulmonary arteries in the peripheral zone, intersegmental veins were easily defined with this method. In five cases of pulmonary cancer that were confirmed to show definite tumor involvement of the pulmonary vessels in the mediastinum and hilum by enhanced CT and MRI (SE method), irregular narrowing and interruption of the vessels were shown on MRA. In conclusion, 2D TOF stereoscopic MRA is considered a noninvasive, effective method for evaluation of the morphology of pulmonary vessels adjacent to the tumor in the mediastinum and hilum.

[Evaluation of breath-hold multislice dynamic MRI of hepatocellular carcinomas].

The breath-hold multislice dynamic study (BMDS) in MRI, which can scan the entire liver during a single breath-holding, was applied to 16 patients with 30 focal lesions of hepatocellular carcinoma (HCC). The BMDS was performed at 20 seconds and 3 minutes after the bolus injection of Gd-DTPA, by gradient echo pulse sequence (FLASH). 29 nodules were detected in the BMDS, showing rapid enhancement on early phase and decline on delayed phase images. The BMDS was more sensitive than conventional MR images. Therefore, the BMDS seems to be useful for the diagnosis of HCC with multiple as well as solitary nodules.

[Evaluation of muscle layer of the uterine body by dynamic MRI].

Gd-DTPA enhanced dynamic MR imaging was performed in 11 normal uteri using a 1.5-T MR unit in order to analyze normal dynamic patterns. After intravenous bolus administration of Gd-DTPA, dynamic study was performed with serial imaging-gradient echo (FLASH). In most cases of normal uteri, early enhancement was shown in peripheral zone that was similar to be junctional zone, forming inner region of muscle layer.

[Clinical evaluation of bronchial artery infusion (BAI) in lung cancer].

Clinical evaluation of 32 cases of primary lung cancer treated with Bronchial Artery Infusion (BAI) were reported. As to the relationship between Bronchial Arteriogram (BAG) and therapeutic effect of BAI, the therapeutic effect of BAI was closely correlated with the degree of neovascularity. And as no correlation was shown between therapeutic effect and histology of lung cancer, the degree of neovascularity on BAG seemed to be more important factor. From the aspect of survival, neovascularity and B-P shunt on BAG showed no correlation with the survival time. On the relationship between survival and histology of lung cancer, squamous cell carcinoma and adenocarcinoma showed almost an equivalent survival. According to the stage of our cases, 25 out of 32 cases were stage III and IV, and they showed relatively better survival, especially stage III, of which MST was 16.6 months, and of which a two year survival rate was 33.5% considering MST and a two year survival rate of stage III A (N2) of non-resected non-small cell lung cancer in other reports are about 12 months and 20%, respectively. BAI is considered to be an effective method among several treatments against lung cancer.

Cytotoxicity of chloropeptide in isolated hepatocytes and its inactivation by microsomes.

Chloropeptide, a hepatotoxic mycotoxin of Penicillium islandicum Sopp, induces gross changes in cell morphology including blebbing and ballooning of the cytoplasmic membrane in the isolated hepatocytes, and this hepatotoxic potential of chloropeptide is abolished by microsomal cytochrome P-450 system.