Nihon Igaku Hoshasen Gakkai zasshi. Nippon acta radiologica最新文献

Purpose: The purpose of this study was to demonstrate and compare the imaging findings of hepatopulmonary syndrome and portopulmonary hypertension.

Materials and methods: We retrospectively reviewed the imaging findings of five patients with hepatopulmonary syndrome and four patients with portopulmonary hypertension. We evaluated chest radiographs, chest and abdominal computed tomography (CT) scans, 99mTc-macroaggregated albumin (MAA) lung perfusion scans, and pulmonary angiograms.

Results: In patients with hepatopulmonary syndrome, the presence of peripheral pulmonary vascular dilatation was detected by chest radiograph, chest CT scan, and pulmonary angiogram, especially the basilar segment. 99mTc-MAA lung perfusion scan showed extrapulmonary tracer distribution (brain, thyroid, and kidney), which revealed pulmonary R-L shunting. In patients with portopulmonary hypertension, chest radiographs and chest CT scans showed the classic findings of primary pulmonary hypertension. In patients with both disorders, extrahepatic features of portal hypertension including ascites, splenomegaly, and portosystemic collateral vessels were seen on abdominal CT.

Conclusion: In conclusion, chest radiographs and CT in hepatopulmonary syndrome usually showed peripheral pulmonary vascular dilatation, whereas those in portopulmonary hypertension showed central pulmonary artery dilatation. The extrahepatic features of portal hypertension might be helpful for the diagnosis of both disorders.

Purpose: The purpose of this study was to clarify the characteristic CT findings of pulmonary hamartoma.

Materials and methods: The thin-section CT and multiplanar reformation images of 19 pulmonary hamartomas diagnosed by surgical resection were analyzed and correlated with the pathological findings.

Results: Most hamartomas presented lobulated nodules apart from pleura. There was no case in which fat density was recognized. Only one case was recognized as having calcification. Air density in the connection of the side or the inside was pointed out in 5 cases (26%). Air density reflected epithelial-lined cleft. The connection with the bronchus was recognized in 4 cases (21%), and the connection with the pulmonary artery branch was recognized in 10 cases (53%). However, the connection of the pulmonary artery and bronchus could not be pathologically confirmed in most cases. The connection with the pulmonary vein was not recognized in any of the cases.

Conclusion: Air density in the connection of the side or the inside is characteristic of pulmonary hamartoma. Pulmonary artery branches connect beyond half of hamartomas. This finding suggests close relations in the bronchus along the artery. It is important that there is no connection of the pulmonary vein, to differentiate it from lung cancer.

We performed CT-angiography twice, first hip joint extension, followed by second flexion. Using vessel analysis software, we placed several points of interest at equal intervals on the center line of the iliac artery, from the bifurcation to the femoral artery inguinal portion, and recorded the their three-dimensional coordinates. We also marked the circumference, which passes by three points that add the respective next point and prior point to each reference point. This curvature (the inverse number of the radius) was utilized as the index that displays crookedness. This method was able to estimate quantitatively the grade of crookedness, and, by comparing an equidistant point from the bifurcation, to show the changes in grade at flexion of the hip joint.

The purpose of this study was to correlate the CT and pathologic findings after radiofrequency ablation (RFA) of rabbit lung and evaluate the therapeutically effective area. RFA was performed in eight rabbit lungs, and ablated regions were imaged immediately after RFA (n=8) and 1 week later (n=4). Immediately after RFA, the ablated regions showed ground-glass opacity. At one week, the ablated region showed very dense opacity, which corresponded to necrotic tissue. Ground-glass opacity signified the therapeutically effective area that would later turn into necrosis.

Sturge-Weber syndrome (SWS) is a phakomatosis characterized by vascular nevus flammeus, leptomeningeal venous angiomatosis, seizures, dementia, hemiplegia, hemianopsia, and glaucoma. Various imaging findings (gyriform calcification, atrophy of the ipsilateral hemisphere, leptomeningeal enhancement, ipsilateral choroid plexus enlargement, thickened calvarium, enlargement of paranasal sinuses and mastoid air cells, enlargement of deep veins, and white matter change adjacent to leptomeningeal enhancement) are seen in SWS. We examined the efficacy of CT and MR imaging in making the diagnosis in 14 patients. All patients underwent CT and MRI, and 11 of 14 patients underwent contrast-enhanced MRI. The most specific finding was leptomeningeal enhancement. Gyriform calcification, atrophy of the ipsilateral hemisphere, and ipsilateral chroid plexus enlargement were seen at high frequencies. Thickened calvarium was more frequent in adult patients. Enlargement of paranasal sinuses and mastoid air cells, enlargement of deep veins, and white matter change adjacent to leptomeningeal enhancement were seen in some (3-5) patients. A combination of findings of plain CT and MRI (including postcontrast MRI and MR venography) are useful for diagnosing SWS.

Purpose: To present the initial experience with proton beam therapy at the new Proton Medical Research Center (PMRC) of the University of Tsukuba.

Materials and methods: The new facility has a synchrotron with maximum energy of 250MeV and two rotational gantries. We treated 105 patients with 120 lesions with proton beams in the first year, beginning in September 2001. The most common lesion treated was primary liver cancer (40 lesions) followed by lung cancer, head and neck cancers, and prostate cancer. Concurrent X-ray radiotherapy was given for 38 of the 120 lesions.

Results: The median follow-up period was 11 months (range, 1-19 months). Of the 105 patients, 97% had Grade 0-2 RTOG/EORTC acute morbidities, while the remaining 3% had Grade 3. Tumor response after irradiation was CR for 35% of the lesions, PR for 25%, SD for 22%, PD for 9%, and not evaluated for 9%.

Conclusion: The proton beam therapy conducted at the new facility of the University of Tsukuba was safe and effective.

Purpose: To examine on HRCT whether there is a difference in the respiratory moving distance of bronchial mucus plugs between ventral and dorsal bronchi.

Materials and methods: We examined 36 ventral and dorsal bronchi of the same order in 18 patients with mucoid impaction depicted on HRCT. CT data were obtained by multidetector-row CT. HRCT images of 0.5 mm thickness and 0.3 mm interval were reconstructed. We selected one slice including a mucus plug take-off from each bronchus. When they were not included in a slice, we reconstructed a 1-3 mm slab-thickness MIP image. In these images we measured the distance between the take-off of each bronchus and the hilar margin of the mucus in same-order ventral and dorsal bronchi. We also measured CT attenuation in the ROI of the subpleural region excluding vessels in the same slice. When the differences in distances (delta D) and CT attenuations (delta C) between inspiration and expiration were obtained, we analyzed the correlation between delta D and delta C in ventral and dorsal bronchi, respectively. We also compared delta D between ventral and dorsal bronchi.

Results: Mean delta C was 36.26 +/- 2.78 HU. Ventral delta D was 6.46 +/- 3.75 mm, and dorsal delta D was 2.57 +/- 1.59 mm. The correlation between delta C and dorsal delta D was significant (r = -0.78, p < 0.005), whereas that between delta C and ventral delta D was not (r = 0.23, p = 0.64). The ventral delta D was significantly smaller than the dorsal (p < 0.05).

Conclusion: Between inspiration and expiration in the supine position, mucus plugs in the ventral bronchi travel less distance than those in the dorsal bronchi.

We encountered a case of giant peritoneal loose body, which was detected on barium enema by chance. Unenhanced CT showed a round mass with calcified center. On MR examination, the mass moved to the pelvic cavity from the position at CT examination. T1- and T2-weighted images showed a mass with low signal intensity. The contrast-enhanced T1-weighted images showed no enhancement. From these findings, peritoneal loose body, in addition to teratoma, granuloma, and foreign body, was suspected. However, the wide window width CT clearly showed a concentric calcification, a finding that is characteristic of peritoneal loose body.

In patients with suspected pneumonia, chest radiography and CT play an important role in making the differential diagnosis and evaluating disease severity and progress. The radiologic patterns of both community-acquired and opportunistic pneumonias were reviewed and compared with those of non-infectious lung diseases. The important findings in the diagnosis of pneumonias were as follows: 1) the relationship between the extent of consolidation and segment or lobe; 2) homogeneity or heterogeneity of opacity; 3) presence of thickening of bronchi and bronchioli; centrilobular, acinar, lobular, and segmental opacities; air bronchogram; tree-inbud appearance, and mosaic perfusion; and 4) size and distribution of nodules.

Seven patients who had elevated amylase activity in the bile at cholecystectomy and seven normal volunteers were prospectively examined by secretin-stimulated dynamic MRCP. Thirty-five consecutive MR cholangiopancreatograms were acquired at intervals of approximately 10 sec after secretin injection; the acquisition time was 4 sec per image. In all normal volunteers, no apparent signal intensity (SI) changes were noted in the intra- and extrahepatic ducts. Of the 7 patients, the extrahepatic duct showed a sequential SI increase from downstream to upstream in 6; its caliber increased subsequent to pancreatic fluid secretion in 5; and duodenal filling grade tended to be lower in the patients (p < 0.01). These findings were thought to be suggestive of pancreaticobiliary reflux.