Development and aging of the cerebrum: assessment with proton MR spectroscopy

BACKGROUND AND PURPOSE

MR spectroscopy allows the noninvasive evaluation of in vivo brain metabolites. Our purpose was to use this technique to assess metabolic alterations in the human cerebrum during growth, maturation, and aging.

METHODS

Ninety normal human brains in subjects aged 4 to 88 years were examined with multivoxel proton MR spectroscopy. Spectra were obtained from specific voxels of 2.5 cm3 in the gray and white matter of the centrum semiovale. The ratios of N-acetylaspartate (NAA) to choline (Cho) were calculated to describe age-dependent alterations in cerebral metabolites.

RESULTS

White matter NAA/Cho ratios showed rapid growth during the first decade and reached a maximum value in the second or early third decade, followed by a steady decline starting in the latter half of the third decade. The maximum peak ages for NAA/Cho were 21.9, 17.6, and 15.9 years (mean, 18.5 years) for the anterior, middle, and posterior white matter, respectively. A significant cerebral laterality of the white matter NAA/Cho was found in male subjects during development. The growth spurt and age-related decline of the white matter NAA/Cho were steeper in male than in female subjects. In contrast, the gray matter NAA/Cho showed a gradual decline with age.

CONCLUSION

Proton MR spectroscopy shows significant regional and sex differences in the level of cerebral metabolites during the process of growth, maturation, and aging. This technique may play an important role in clinical applications for various conditions of metabolic disorders of the human brain.

Low-cost soft-copy display accuracy in the detection of pulmonary nodules by single-exposure dual-energy subtraction: comparison with hard-copy viewing

This study endeavored to clarify the usefulness of single-exposure dual-energy subtraction computed radiography (CR) of the chest and the ability of soft-copy images to detect low-contrast simulated pulmonary nodules. Conventional and bone-subtracted CR images of 25 chest phantom image sets with a low-contrast nylon nodule and 25 without a nodule were interpreted by 12 observers (6 radiologists, 6 chest physicians) who rated each on a continuous confidence scale and marked the position of the nodule if one was present. Hard-copy images were 7 x 7-inch laser-printed CR films, and soft-copy images were displayed on a 21-inch noninterlaced color CRT monitor with an optimized dynamic range. Soft-copy images were adjusted to the same size as hard-copy images and were viewed under darkened illumination in the reading room. No significant differences were found between hard- and soft-copy images. In conclusion, the soft-copy images were found to be useful in detecting low-contrast simulated pulmonary nodules.

Comparison between computer-aided diagnosis and radiologists: assessment of pulmonary blood flow on chest radiographs

To evaluate the performance of a computer-aided diagnosis (CAD) scheme for estimating increased pulmonary blood flow on chest radiographs, we compared computerized assessment with findings by radiologists. Our CAD scheme extracts selectively linear opacities corresponding to vessels in regions of interest (ROIs) in the right upper and lower lung zones on digitized chest radiographs, and then calculates a radiographic index as a physical measure that reflects the area of the extracted opacities in selected ROIs. As a measure of increased pulmonary blood flow, the upper/lower radiographic index ratio was calculated for each patient. Seven radiologists estimated the degree of increased pulmonary blood flow for the same images of ROI sets presented on a cathode-ray tube monitor in a randomized order. Between the normal-pulmonary capillary wedge pressure (PCWP) group and increased-PCWP groups, there was no significant difference in performance between CAD and radiologists (p = 0.105). However, when the normal and mild PCWP groups were compared, the performance of CAD was superior to that of radiologists (p = 0.001). This study indicates that our CAD scheme is promising for quantitative estimation of increased pulmonary blood flow, especially in mild cases.

Ground-glass opacity on thin-section CT: value in differentiating subtypes of adenocarcinoma of the lung

OBJECTIVE

The purpose of this study was to determine whether thin-section CT could be used to differentiate small localized bronchioloalveolar carcinoma from peripheral adenocarcinoma having a bronchioloalveolar (replacement) growth pattern of alveolar lining cells and from adenocarcinoma not having a replacement growth pattern on the basis of the extent of ground-glass opacity revealed by thin-section CT.

MATERIALS AND METHODS

One hundred twenty-four small, surgically resected, peripheral adenocarcinomas from 119 patients (67 men and 52 women; mean age, 60 years) were studied. Lesion diameters were 0.4-2.0 cm (median, 1.5 cm). The extent of ground-glass opacity within lesions on preoperative thin-section CT was reviewed retrospectively by three thoracic radiologists. On the basis of replacement growth of alveolar lining cells, small adenocarcinomas were classified histologically as localized bronchioloalveolar carcinomas (n = 42) or as adenocarcinomas with (n = 53) or without (n = 29) a replacement growth pattern of alveolar lining cells.

RESULTS

The percentage of lesions that had ground-glass opacity was significantly greater in localized bronchioloalveolar carcinomas (mean, 56.7%+/-33.0%) than in adenocarcinomas with a replacement growth pattern (mean, 26.3%+/-25.3%, p < .001) or in adenocarcinomas without a replacement growth pattern (mean, 8.3%+/-4.7%, p < .001).

CONCLUSION

Determination of the ground-glass opacity area in each tumor as revealed on thin-section CT was useful for differentiating small localized bronchioloalveolar carcinomas from small adenocarcinomas not having a replacement growth pattern.

Survey of 222Rn concentrations in the air of a tunnel located in Nagano City using the solid-state nuclear track detector method

The survey of 222Rn concentration in the air of tunnels constructed during World War II has been performed using a solid-state nuclear track detector technique. For the practical application of this technique to the determination of 222Rn concentrations in air, some basic properties were experimentally examined on the cellulose nitrate film, Kodak LR 115 type II. The calibration coefficient of the cellulose nitrate film used is determined from a correlation between the 222Rn concentration in air and the observed number of perforated etched tracks for widespread radon concentrations. The slope of the linear relationship observed yields a calibration coefficient of (0.00209 +/- 0.00018) tracks cm(-2) (Bq m(-3) h)(-1). From the survey of 222Rn concentration in the air of tunnels, the concentration of several thousand Bq m(-3) was observed at the inner most area of the tunnel, and the seasonal variation was clearly observed. The exponential distribution of radon concentration as a function of distance from the openings of the tunnel suggests that the radon concentration in the tunnel is basically governed by diffusion and mixing of radon gas with air.

Interstitial lung diseases: evaluation of the performance of a computerized analysis system versus observers

We have been developing a computerized analysis system to detect interstitial lung abnormalities on chest radiographs. In this study, we evaluated the performance of our computerized analysis system and compared it with that of radiologists. The performance of the computerized analysis system was inferior to the mean performance of the chest radiologists. However, the performance of the computerized analysis system was superior to the mean performance of the residents. From our results, the outputs obtained from the computerized analysis system can be used by radiologists as a "second opinion", and this system could be especially useful to obtain quantitative data for follow-up of known interstitial lung diseases.

Minute carcinoma of the pancreas measuring 1 cm or less in diameter--collective review of Japanese case reports

BACKGROUND/AIMS

According to Tsuchiya's collective review on small pancreatic cancer measuring 2 cm or less in diameter (5), more than half of them had obstructive jaundice and the 5-year survival rate was as low as 30%. Thus, a more aggressive diagnostic approach is needed to detect a smaller and more curable cancer of the pancreas.

METHODOLOGY

Thus, we collected 36 reported cases of "minute" pancreatic cancer measuring 1 cm or less in diameter, from Japanese medical literature, to analyze the relationships between the diagnostic processes and long-term results.

RESULTS

Excluding 3 patients with obstructive jaundice, the other 33 patients did not show any specific initial symptoms. However, 28 (78%) out of 36 patients showed an elevation in serum pancreatic enzyme levels and/or glucose intolerance. Among the 35 patients who had received ultrasonography (US) and/or computed tomography (CT), 20 (57%) patients showed duct dilation alone, whereas only 9 patients (26%) showed tumor mass. Among 35 patients who received an endoscopic retrograde pancreatography (ERP), all patients showed positive findings such as obstruction/stenosis, filling defect or duct dilation. All 36 patients underwent pancreatectomy and the 5-year survival rate was 57%. However, the 5-year survival rate was 34% in the 13 patients with jaundice and/or tumor mass depicted in US/CT, while it was 69% for the 22 patients without these two findings (p < 0.05).

CONCLUSIONS

These data lead us to conclude that an elevation of serum pancreatic enzyme levels, glucose intolerance, and duct dilation alone depicted by US/CT should not be overlooked. ERP should be more widely applied to such patients, instead of persisting in delineating the tumor mass by US/CT or follow-up by tumor marker.

Comparison of computed tomography and pathologic examination for evaluation of response of primary lung cancer to neoadjuvant therapy

Twenty-four patients (nine with squamous cell carcinoma, 14 with adenocarcinoma, and one with large cell carcinoma) underwent neoadjuvant therapy followed by surgical resection. The authors studied changes in tumor size, shape, and contrast enhancement on computed tomography (CT), and compared them with results of pathologic examination of surgical specimens. The size of tumors on CT was evaluated according to the criteria of the World Health Organization. Surgical specimens were evaluated histologically on the basis of the area of viable cancer cells. Of 14 patients considered to have a partial response on the basis of World Health Organization criteria, five had pathologic changes of complete response. After therapy, the residual tumors in these five patients showed irregular shapes with concave tumor margins on CT images and no enhancement. The authors found that CT size criteria tended to underestimate the therapeutic effect demonstrated by pathologic examination. On the basis of these results, the authors propose three CT criteria for complete response: 1) more than 50% size reduction, 2) a change in tumor morphologic features from round or oval to irregular after neoadjuvant therapy, and 3) disappearance of contrast enhancement.

Oxygen administration during hepatic DSA

The research presented in this article examined the role of oxygen in preventing diaphragmatic motion artifacts in delayed-phase hepatic digital subtraction angiography (DSA). The results demonstrate that administering oxygen to patients before the examination substantially reduces artifacts due to motion.

Pancreatic invasion as the prognostic indicator of duodenal adenocarcinoma treated by pancreatoduodenectomy plus extended lymphadenectomy

Pancreatoduodenectomy has become the standard procedure in resection of the duodenal adenocarcinoma, and some adjuvant therapies can be added to obtain further improvement in postoperative outcome. However, for patient selection, it is necessary to have a predictive indicator showing, if possible before laparotomy, which instances are noncurable by surgery alone or need adjuvant therapies.

METHODS

A retrospective analysis was made for 24 consecutive patients whose duodenal adenocarcinoma were treated by pancreatoduodenectomy plus a wide range of lymphadenectomies without any adjuvant therapies at Osaka Medical Center for Cancer and Cardiovascular Diseases. Patient survival rates were related to macroscopic and microscopic findings and to findings obtained by preoperative imaging techniques.

RESULTS

The overall survival rate was 69% at 3 years and 57% at 5 years; locoregional recurrence was the primary cause of death. Although the 5-year survival rate was 44% in patients with nodal involvement and 76% in those without, this difference did not reach statistical significance (P = .079). Instead, invasion into the pancreatic parenchyma at a macroscopic level was the most significant prognostic factor; the 5-year survival rate was 78% in the 16 patients without and 16% in the 8 patients with pancreatic invasion (P = .0047). Invasion into the pancreas correlated well with the angiographic findings; the 5-year survival rate was 25% in patients whose angiograms delineated the pancreatic invasion and 83% in patients whose angiograms did not (P = .0084).

CONCLUSION

When duodenal adenocarcinoma was treated by pancreatoduodenectomy plus a wide range of lymphadenectomy, pancreatic invasion at a macroscopic level was most associated with patient survival. Pancreatic invasion was well delineated by the preoperative angiogram, which would be helpful in patient selection.

[A measure to continue intra-arterial infusion chemotherapy long-term for locally advanced pancreatic cancer]

For locally advanced non-resectable cancer of the pancreas, we have routinely performed intra-arterial chemotherapy: Each catheter is placed in the splenic artery and gastroduodenal artery during laparotomy, and a mixture of Methotrexate and Angiotensin-II is infused within 30 minutes. This treatment is repeated weekly at our outpatient clinic as long as possible. However, obstruction of the catheter or corresponding artery is the major cause of interruption of treatment. The present paper reports a case in which intra-arterial chemotherapy was possible by repeated catheterization for the catheter obstruction. A 54-year-old woman with non-resectable pancreatic cancer underwent catheter placement during laparotomy, but they became occluded one month later. Another catheter was placed into the common hepatic artery by the Seldinger method. After this catheter was occluded again, another catheter was placed into the inferior pancreaticoduodenal artery via the superior mesenteric artery by the Seldinger method. By repeating this catheter placement, we succeeded in continuing the intra-arterial chemotherapy, and the patient has remained alive (30 postoperative months) without losing her quality of life.

Quantification of interstitial lung abnormalities with chest radiography: comparison of radiographic index and fractal dimension

RATIONALE AND OBJECTIVES

The authors performed this study to evaluate two physical measures used for quantifying interstitial lung abnormalities on chest radiographs: the normalized radiographic index (RI) and the fractal dimension (FD).

MATERIALS AND METHODS

The RI and FD were obtained from 50 regions of interest (ROIs) in lungs with mild interstitial abnormalities, 50 ROIs in lungs with severe interstitial abnormalities, and 50 ROIs in normal lungs. The RI was defined as the normalized percentage area of extracted opacities in selected ROIs. FD was calculated with a box-counting algorithm. To extract linear opacities selectively, the authors processed ROIs with four-directional Laplacian-Gaussian filtering and binarization, linear opacity judgment (LOJ), and linear opacity subtraction (LOS). The usefulness of the physical measures for quantifying interstitial lung abnormalities was evaluated with receiver operating characteristic analysis.

RESULTS

In normal and mild abnormality groups, observer performance with the RI was worse with LOJ images (area under the receiver operating characteristic curve [Az] = .812 +/- .042) than with LOS images (Az = .912 +/- .028, P < .05), and performance with FD was better with LOJ images (Az = .867 +/- .037) than with LOS images (Az = .750 +/- .048, P < .05). In the normal and severe abnormality groups, performance with RI and FD was better with LOJ images (RI: Az = .992 +/- .007; FD: Az = .968 +/- .016) than with LOS images (RI: Az = .883 +/- .034, P < .001; FD: Az = .767 +/- .047, P < .0001).

CONCLUSION

The RI is considered to reflect the sensitivity in the detection of interstitial lung abnormalities on chest radiographs. Conversely, the FD is considered to reflect specifically the linear opacities processed with LOJ.

Malignant glioma. Evaluation with 3D time-of-flight MR angiography

PURPOSE

To investigate the clinical utility of 3D time-of-flight (TOF) MR angiography (MRA) in the evaluation of pathological vessels in patients with malignant glioma.

MATERIAL AND METHODS

Sixteen patients with malignant glioma (12 with glioblastoma multiforme and 4 with anaplastic astrocytoma) were examined with 3D TOF MRA before and after the injection of gadopentetate dimeglumine. The 3D TOF MRA study was compared with conventional angiography in all patients.

RESULTS

The unenhanced 3D TOF MRAs successfully depicted the feeding arteries in 9 patients but failed to depict small feeding arteries in 2 patients in whom these arteries were shown by conventional angiography. The enhanced MRAs demonstrated draining veins from the lesions in 8 patients but failed to depict a draining vein in 1 patient that was shown by conventional angiography. The stereoscopic view projection effectively depicted displacements of the major cerebral arteries in 14 patients, and deep venous structures in 11 patients which almost accorded with the findings at conventional angiography.

CONCLUSION

Our results indicate that 3D TOF MRA can provide an accurate visualization of pathological vascular structures and thus help establish a diagnosis in patients with malignant glioma.

[The usefulness of fractal geometry for the diagnosis of small peripheral lung tumors]

PURPOSE

To assess the usefulness of fractal geometry in quantitatively evaluating the convergence of peripheral vessels on peripheral lung tumors in maximum intensity projection (MIP) images.

MATERIALS AND METHODS

We studied the MIP images of 34 pathologically proved small peripheral lung tumors (lung cancer in 21, hamartoma in 13) in 34 patients. To obtain MIP images, spiral CT (SOMATOM PLUS; Siemens) was performed during a single breath hold (24-second scan time, 2-mm section thickness, and 2 mm/sec table feed time, reconstructed at 1-mm increments). To evaluate the convergence of the peripheral vessels and bronchi towards the tumor, we fixed a region of interest (ROI) on the hilar side of the lung tumor, parallel to the chest wall, which consisted of 64 x 64 square pixels, in the images that divided at the center of the window width. We counted the overlapping pixels by the two-dimensional box-counting method and obtained fractal dimensional data on lung cancers and hamartomas.

RESULTS

There was a statistically significant difference in the fractal dimension (D) between lung cancers (D = 1.81 +/- 0.13) and hamartomas (D = 1.67 +/- 0.10) (P = 0.0067).

CONCLUSION

Fractal geometry could be useful in the diagnosis of small peripheral lung tumors.

Spiral CT during pharmacoangiography with angiotensin II in patients with pancreatic disease. Technique and diagnostic efficacy

PURPOSE

To compare the diagnostic efficacy of pancreatic pharmacoangiographic CT using angiotensin II with conventional angiographic CT.

MATERIAL AND METHODS

Eighteen patients with space-occupying pancreatic disease were examined in this study. Pharmacoangiographic CT was performed with a 1-3 micrograms/6-ml solution of angiotensin II injected through a catheter into the celiac artery during spiral CT.

RESULTS

In 17 of the 18 (94%) patients, the area of pancreatic parenchymal enhancement was the same or larger at pharmacoangiographic CT than at conventional angiographic CT. The attenuation value of the pancreatic parenchyma was significantly increased at pharmacoangiographic CT (p = 0.0010). Although the attenuation value of tumors was also increased on images obtained after the injection of angiotensin II, the tumor-to-pancreas contrast was significantly greater at pharmacoangiographic CT (p = 0.0479). The mean differences in attenuation between tumor and pancreas at angiographic CT with and without angiotensin II were respectively 182 HU and 115 HU.

CONCLUSION

Pharmacoangiographic CT with angiotensin II proved superior to conventional angiographic CT in the diagnosis of pancreatic disease. We therefore recommend it as a supplementary technique at the angiographic examination of patients with suspected pancreatic tumor.

[Our initial experience with SMANCS in TAE for liver cancer]

To evaluate the efficacy and adverse reaction of SMANCS, we reviewed 10 cases treated by TAE with SMANCS among 896 cases treated by TAE for liver cancer during the past three years at our institute. Our criteria for using SMANCS were as follows: a) reduced effectiveness of past TAE with Lipiodol, hydrophilic drugs and gelatin sponge; b) sufficient caliber and blood flow in the hepatic artery; and c) good hepatic function. The 1- and 2-year survival rates after treatment with SMANCS were 50% and 25%, respectively. The 3- and 5-year survival rates after initial treatment (first TAE, etc.) were 40% and 20%, respectively. There were no significant complications in clinical course, however, subsequent hepatic arteriogram often showed arterial change that may interfere with further regional therapy for the liver.

Double phase CT arteriography of the whole liver in the evaluation of hepatic tumors

PURPOSE

Our goal was to evaluate the contribution of double phase CT arteriography (CTA) of the whole liver to differentiate hepatic tumors from false-positive areas on CT during arterial portography (CTAP).

METHODS

In 38 candidates for surgical resection of hepatic tumors, both CTAP and double phase CTA were performed. A total of 68 perfusion defects were identified at CTAP. Of 68 perfusion defects, 47 were found to represent hepatic tumors [hepatocellular carcinoma (HCC), n = 31; hepatic metastasis, n = 13; cholangiocarcinoma n = 2; focal nodular hyperplasia, n = 1]. The other 21 perfusion defects were defined as perfusion abnormalities in which focal hepatic masses had not been identified at surgery or pathologic analysis. The phase one CTA scanning started 12 s after the beginning of the injection of contrast material, and the phase two CTA scanning started 20 s after the end of the phase one CTA, with 60 ml of contrast agent (150 mg I/ml) injected at a rate of 2 ml/s.

RESULTS

On phase one CTA, only 1 lesion in 31 HCCs showed rim enhancement and 26 HCCs (84%) had rim enhancement on phase two CTA. Twelve lesions (80%) of the hepatic metastases and cholangiocarcinomas had rim enhancement on phase one CTA and 11 lesions (73%) showed rim enhancement on phase two CTA. Twenty-one perfusion abnormalities on CTAP did not show rim enhancement on either phase one or phase two CTA.

CONCLUSION

Double phase CT arteriography of the whole liver was useful to differentiate hepatic tumors from perfusion abnormalities on CTAP.

[Unruptured intracranial aneurysms: evaluation with high-resolution MR angiography with magnetization transfer contrast (MTC) and tilted optimized nonsaturating excitation (TONE)]

Forty-one patients with suspected intracranial aneurysms were evaluated by conventional three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA) or high-resolution 3D TOF MRA with magnetization transfer contrast (MTC) and tilted optimized nonsaturating excitation (TONE). Correlative study was done with conventional angiography in all patients. 3D TOF MRA detected 30 of 36 aneurysms depicted at conventional angiography. The overall rate of sensitivity for the detection of aneurysms was 83%. Unruptured aneurysms were unlikely to occur in the anterior communicating artery (3%), but were frequently found at the bifurcation of the middle cerebral artery (33%). Conventional MRA showed 7 of 9 aneurysms demonstrated at catheter angiography. The rate of sensitivity of conventional MRA for aneurysms smaller than 5 mm and greater than or equal to 5 mm were 0% and 100%, respectively. High resolution MRA with MTC and TONE demonstrated 23 of 27 aneurysms detected by catheter angiography. Sensitivities of high resolution MRA with MTC and TONE for aneurysms smaller than 5 mm and greater than or equal to 5 mm were 71% and 100%, respectively. Our results indicate that high-resolution 3D TOF MRA with MTC and TONE can provide precise, accurate depiction of intracranial aneurysms larger than or equal to 5 mm.

Computerized radiographic assessment of pulmonary blood flow in patients with and those without mitral stenosis

The authors investigated whether a computerized analysis system can be used with chest radiography for estimating the redistribution of pulmonary blood flow in patients with and those without mitral stenosis (MS). Their system uses four-directional Laplacian-Gaussian filtering and binarization. As a physical measure, the radiographic index, which reflects the area of opacity in selected regions of interest (ROIs), was used. Fifteen men with MS and 15 men without MS were included in the study. ROIs were selected in the right upper and lower lung zones on radiographs, and the images were processed with the system. The radiographic indexes were determined in each ROI. As a measure of pulmonary blood flow redistribution, the upper-to-lower lung zone radiographic index ratio (U/L) was calculated. The U/L values correlated with pulmonary capillary wedge pressure values (r = .405, P = .025). The mean U/L value of the MS group was significantly higher than that of the non-MS group (1.16 +/- 0.14 vs 1.05 +/- 0.09, respectively; P = .016). These preliminary results indicate that this system can be used for quantitative estimation of the redistribution of pulmonary blood flow.

[A case report of preoperative intra-arterial infusion chemotherapy for pancreatic head carcinoma]

Intra-arterial infusion chemotherapy was given preoperatively to one patient with pancreatic head adenocarcinoma, in order to prevent local failure after surgery. Under an angiographic procedure, a catheter was placed in the gastroduodenal artery after embolizing the right gastric artery and gastroepiploic artery. Before surgery, 5-fluorouracil (250 mg/day) had been continuously infused for 2 weeks and bolus infusion of methotrexate (25 mg) with 5 micrograms of angiotensin-II had been performed every 3 days. As a results, the maximum diameter of the pancreatic tumor decreased from 3 cm to 2 cm on the CT-Scan. An extended pancreatoduodenectomy with portal vein reconstruction was performed. In histologic study, degenerative tumor cells were shown not only in the primary tumor but also in the extrapancreatic perineural invasion.

[An adult case of mediastinal lymphangioma]

Mediastinal lymphangioma is rare (less than 1%) and is usually not discovered until adulthood because of its asymptomatic nature and deeply seated location. We experienced an adult case of mediastinal lymphangioma. CT and MRI showed a non-invasive multilocular cystic mass spreading in the potential space of the mediastinum including the precardiovascular region and central region. To determine the extent of the tumor, the concept of the potential space of the mediastinum was useful in making the differential diagnosis of cystic mediastinal tumor.

Reducing misregistration of mask image in hepatic DSA

When performing hepatic digital subtraction angiography, misregistration of the mask image can cause artifacts that obscure pathology. For this article, researchers analyzed the breath expiration times of 59 patients and found that expiration times ranged from 1.8 seconds to 6 seconds. Thirty DSA series were obtained taking into account the patient's breath expiration time, and 35 series were obtained without taking the expiration time into consideration. Artifacts were detected in 20% of the DSA series where expiration time was taken into consideration and in 42.9% of series where it was not (p < 0.05). The research showed that misregistration of the mask image during hepatic DSA can be reduced by starting the exposure at the end of breath expiration.

Paradoxic uptake of Gd-EOB-DTPA by hepatocellular carcinoma in mice: quantitative image analysis

To determine whether paradoxic uptake of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) occurs only with highly differentiated hepatocellular carcinomas, quantitative image analysis was performed in 37 mice with 133 hepatocellular carcinomas. The results of lesion/ liver signal intensity measurement and relative enhancement calculation indicate that paradoxic positive enhancement occurs independently of cellular differentiation.

Types of diaphragmatic motion during hepatic angiography

To determine the types and causes of diaphragmatic motion during hepatic angiography, the authors used transarterial cut-film portography (TAP) to study movement of the diaphragm during breath-holding. Thirty-three TAP sequences were studied, and the patients' diaphragmatic motions were classified into four categories according to the distance their diaphragms moved. Results showed that the diaphragm was stationary in 33% of the TAP studies, while perpetual motion occurred in 15% of the studies, early-phase motion occurred in 12% and late-phase motion occurred in 40%. Ten sequences showed diaphragmatic motion of more than 10 mm, with eight sequences showing caudal motion and two showing cranial motion. This article discusses the cause of diaphragmatic motion during breath-holding for hepatic angiography and presents suggestions to reduce motion artifacts during the exam.

A computerized analysis system in chest radiography: evaluation of interstitial lung abnormalities

We evaluated the usefulness of a computerized analysis system in the detection of interstitial lung abnormalities in digitized chest radiography. This system uses the processes of four-directional Laplacian-Gaussian filtering, linear opacity judgment, and linear opacity subtraction. For qualitative analysis, we employed a combined radiographic index, which was calculated from two normalized radiographic indices obtained by linear opacity judgment and subtraction of linear opacities. We selected 50 regions of interest (ROIs) in patients with mild interstitial lung abnormalities, 50 ROIs in patients with severe interstitial lung abnormalities, and 50 ROIs in individuals with normal lung parenchyma. High-resolution computed radiography (HRCT) findings were used as the standard of reference for this study. These ROIs were processed by our computerized analysis system, and radiographic indices were obtained from each ROI. The area under the receiver operating characteristic curve (Az) was used as the measure of performance. The combined radiographic index provided better results in the mild interstitial lung abnormality group (Az = 0.94 +/- 0.02), but it also yielded good results in the severe interstitial lung abnormality group (Az = 0.98 +/- 0.01). These results indicate that this system of combining radiographic indices has improved the detection performance over that with our previous system.

Prospective and randomized trial of lipiodol-transcatheter arterial chemoembolization for treatment of hepatocellular carcinoma: a comparison of epirubicin and doxorubicin (second cooperative study). The Cooperative Study Group for Liver Cancer Treatment of Japan

A randomized, controlled clinical trial was conducted to compare the use of epirubicin (EPI) and doxorubicin (DOX) in Lipiodol (Laboratoire Guerbet, Roissy-Charles-de-Gaulle Cedex, France)-transcatheter arterial chemoembolization as a treatment of hepatocellular carcinoma. One hundred ninety-two hospitals participated, and 415 patients were enrolled in the study during the period between October 1989 and December 1990. The patients were randomly allocated to group A (EPI) or group B (DOX) by a centralized telephone registration. The actual doses of EPI and DOX were 72 mg/body and 48 mg/body, respectively. The 1-, 2-, and 3-year survival rates were, respectively, 69%, 44%, and 33% for group A and 73%, 54%, and 37% for group B. There were no statistically significant differences (P = .2296, log-rank test). When each group of patients was classified retrospectively into high-risk and low-risk subgroups based on the severity index calculated by the Cox regression model from the significant prognostic factors (the pretreatment tumor size, the pretreatment serum alpha-fetoprotein level, tumor encroachment, and Child's classification), the survival curve of the low-risk DOX subgroup was significantly superior to that of the low-risk EPI subgroup (P = .0182). However, there was no significant difference between the high-risk subgroups (P = .4606). The change in the serum alpha-fetoprotein level, the extent of Lipiodol accumulation in the tumor, and the extent of tumor reduction after the treatment did not show any significant differences between the groups. The white blood cell count in group B showed a tendency to decrease slightly more than in group A at 3 weeks after Lipiodol-transcatheter arterial chemoembolization. In conclusion, there was no statistically significant difference between the survival curves of the EPI and DOX groups in Lipiodol-transcatheter arterial embolization treatment of hepatocellular carcinoma.

MR imaging evaluation of renal cell carcinoma

BACKGROUND

This study examines the minimally required imaging protocol needed for detection and staging of renal cell carcinoma (RCC).

METHODS

In 81 patients (21 women, 60 men; mean age = 62 years) with 85 RCCs, T1-weighted (T1WI), contrast-enhanced T1-weighted (Gd-T1WI), T2-weighted (T2WI), and gradient recalled echo-fast low flip angle shot (GRE/FLASH) images were evaluated alone and in combination. Surgical-pathological findings were available in all patients and were considered the standard of reference.

RESULTS

Tumor detection for lesions smaller than 3 cm was better on Gd-T1WI than on any other sequence, but only the comparison with noncontrast T1WI and GRE/FLASH was statistically significant (detection: T1WI = 33%, Gd-TIWI = 80%, T2WI = 60%, GRE = 47%). The respective accuracies of T1WI, Gd-T1WI, T2WI, and GRE/FLASH images were 81%, 78%, 71%, and 62% for evaluating local tumor extension; 90%, 88%, 89%, and 85% for lymphadenopathy; and 89%, 81%, 91%, and 95% for renal vein thrombus. The combination of T1WI and GRE sequences rendered the highest overall staging accuracy.

CONCLUSION

For tumor detection, contrast-enhanced T1WI is necessary for lesions smaller than 3 cm. For tumor staging, although the addition of GRE results in significant improvement in the evaluation of venous thrombus, any combination of two sequences will result in similar accuracy, and the use of multiple sequences is not necessary.

Using compensating filters to reduce radiation dose

The study described in this article explores the role of compensating filters in reducing radiation exposure. Radiation exposure levels with and without filters were compared in skull radiographs, hepatic angiographs and one-shot full-length lower extremity radiographs. Absorbed doses were measured with and without a skull filter in a phantom at a depth of 5 cm. Results showed that filters reduced exposure by 29% in skull radiographs, 47% in hepatic angiographs and 80% in one-shot full-length lower extremity radiographs. Absorbed doses were reduced by more than 26% in the skull phantom in the filtered area. To reduce patient dose, the filters were positioned between the x-ray tube and the patient.

MR of xanthogranuloma of the choroid plexus

We present a case of a xanthogranuloma of the lateral ventricle choroid plexus in association with focal areas of abnormal T2 signal in the tegmentum of the pons as well as within the middle cerebellar peduncles. The characteristic MR appearance of this rare entity is described along with a pathologic basis suggesting an association with posterior fossa lesions.

Contrast enhancement with Gd-EOB-DTPA in MR imaging of hepatocellular carcinoma in mice: a comparison with superparamagnetic iron oxide

The purpose of this study was to evaluate the ability of the new liver-specific magnetic resonance contrast agent gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) to detect hepatocellular carcinoma (HCC). Seventeen mice with 66 chemically induced HCCs underwent magnetic resonance imaging with both Gd-EOB-DTPA (30 mumol/kg) and superparamagnetic iron oxide (SPIO; 10 mumol/kg). After enhancement, lesion-to-liver contrast-to-noise ratios (CNRs) of 47 detected HCCs increased negatively from 3.7 +/- 10.7 (mean +/- SD) to -55.1 +/- 25.8 with Gd-EOB-DTPA (P < .001) and increased positively from 10.4 +/- 10.4 to 26.1 +/- 16.3 with SPIO (P < .001). The improvement of CNR after administration of SPIO was less in smaller lesions (< 4 mm), whereas that after administration of Gd-EOB-DTPA was independent of lesion size. However, Gd-EOB-DTPA positively enhanced four HCCs (8.5%), both highly differentiated (grade 1) and moderately differentiated (grade 2). Gd-EOB-DTPA allows the conspicuous detection of small HCCs; however, moderately differentiated HCCs occasionally may be positively enhanced.

Clinical features of small hepatocellular carcinomas as assessed by histologic grades

BACKGROUND

Ninety-seven patients with small hepatocellular carcinomas (HCCs) measuring 3 cm or less in size and three patients with adenomatous hyperplasia who underwent radical hepatic resection were examined in this study.

METHODS

The lesions were classified into four groups according to the following histologic grading criteria: group A, adenomatous hyperplasia (n = 3); group B, early HCC (n = 6); group C, well-differentiated HCC (wHCC) (n = 32); and group D, moderately or poorly differentiated HCC (n = 59). The involvement factors that seemed to be important or to characterize the progression of HCC and the survival rates were compared among the four histologic groups.

RESULTS

The frequency of patients with tumors larger than 2.0 cm in size and that of patients with 200 or more ng/ml serum alpha-fetoprotein increased with the progression of histologic malignancy. Tumor staining on the angiogram, capsular formation, and extranodular invasion were never seen in groups A and B, but they began to appear in group C and increased remarkably in group D. The 5-year survival rates of the patients in groups B, C, and D were 100%, 60%, and 27%, respectively, and statistically significant differences were seen among them. In comparative evaluation of the group C patients the lesions that showed no tumor staining had no capsule, and those that had no capsule had no extranodular invasion. The 5-year survival rate of patients with wHCC without extranodular invasion (81%) was significantly higher than that of patients with extranodular invasion (35%) (p < 0.05).

CONCLUSIONS

It may be recommended to provide the category of wHCC without extranodular invasion for pathologic classification of clinically early HCC (i.e., HCC of high curability).

[Usefulness of spiral CT in the detection of hypovascular, well-differentiated hepatocellular carcinoma]

Whole liver scanning during artery-dominant phase using spiral CT was performed in 14 patients with 17 histologically proven well-differentiated HCCs, which were not depicted by hepatic digital subtraction angiography but by CT during arterial portography. The density of HCC relative to the liver was evaluated with conventional precontrast CT, spiral CT, and following conventional CT during the equilibrium phase. Comparison between spiral CT and magnetic resonance (MR) imaging of dynamic contrast studies was also investigated. Four tumors of 17 HCCs (24%) were shown as a high-density area by the artery-dominant phase using spiral CT. Consequently, the total sensitivity of these three kinds of CT techniques was elevated to 82%. The sensitivity of dynamic MR imaging was slightly greater than that of spiral CT. However, spiral CT sometimes made the diagnosis more conspicuous by it's good spatial resolution. Our results indicate that spiral CT has a potential benefit in the detection of hypovascular well-differentiated HCC, and MR imaging and spiral CT may be complement each other.

[Double lumen--coaxial catheter system for combined CT during arterial portography and CT hepatic angiography]

The high sensitivity of CT during arterial portography (CTAP) for hepatic lesions is accompanied with a lack of specificity for diagnosis. Combined CTAP and CT hepatic angiograpy (CTHA) had been proved to improves lesion detection and heightens confidence in interpreting perfusion abnormalities. We describe a new double lumen - coaxial catheter system for performing combined CTAP and CTHA without the need for repeated transfer of the patient or bilateral arterial punctures. This technique was employed in eight patients with liver neoplasms. In all eight patients, CTAP and CTA images were obtained successfully. We concluded that this method was useful for the evaluation of liver tumors.

G10BP, an E1A-inducible negative regulator of Sp1, represses transcription of the rat fibronectin gene

Downregulation of the fibronectin (FN) gene in a rat 3Y1 derivative cell line, XhoC, transformed by the adenovirus E1A and E1B genes seems to be caused by the induction of a negative regulator, G10BP, which binds to three G-rich sequences in the promoter (T. Nakamura, T. Nakajima, S. Tsunoda, S. Nakada, K. Oda, H. Tsurui, and A. Wada, J. Virol. 66:6436-6450, 1992). These are the G10 stretch and two GC boxes consisting of the G10 stretch with one internal C residue insertion. The recognition sequences of G10BP and Sp1 (GGGCGG) overlap in these GC boxes. To analyze the mechanism of the downregulation, G10BP was purified by DNA affinity chromatography, and its molecular mass was estimated to be about 30 kDa. The promoter was modified by substituting the sequence GGGG with ATCC or CTTA in these G-rich sequences, leaving the Sp1 motif intact, and by replacing the Sp1 motif by the T stretch. Transcription of FN promoter-chloramphenicol acetyltransferase fusion genes carrying the base substitution in one or more of these G-rich sequences both in vivo and in vitro revealed that the base substitution in any G-rich sequence results in reduction of promoter activity, although the downstream GC box (GCd) plays a primary role. The addition of G10BP severely inhibited the activities of the FN promoters carrying the wild-type GCd in vitro, while the promoters carrying the mutant GCd were unaffected. The binding affinity of G10BP and Sp1 to each of the G-rich sequences, analyzed by gel shift assays, indicated that G10BP binds strongly to the GCd, moderately to the G10 stretch, and weakly to GCu, while Sp1 binds strongly to GCu, moderately to GCd, and weakly to the G10 stretch. Sp1 binding to GCd and the G10 stretch was inhibited by G10BP, while binding to GCu was unaffected. These results indicate that FN gene transcription is inhibited in XhoC cells primarily by exclusion of Sp1 binding to GCd by G10BP and that G10BP is a new class of Sp1 negative regulator.

Comparative safety and efficacy of two immune globulin products in Kawasaki disease

OBJECTIVE

To compare the safety and efficacy of various intravenously administered immune globulin (IVGG) products in patients with Kawasaki disease.

METHODS

We performed a retrospective matched-pair study of 45 pairs of patients, matched by age, gender, hospital, and illness day when IVGG therapy was initiated. All patients received aspirin, 80 to 100 mg/kg per day; one of each pair received Venoglobulin, 2 gm/kg (product A), and the other received Iveegam, 2 gm/kg (product B). Safety was assessed during and after IVGG infusion by recording rigors, pruritus, hypotension, urticaria, and nausea. Treatment efficacy was evaluated by posttreatment height and duration of fever, and subsequent echocardiographic changes.

RESULTS

Untoward reactions during infusions occurred more often with product A (25%) than with product B (2%) (p < 0.025); most reactions were rigors (18% vs 2%) (p < 0.05). Therapy was completed in all patients. Height of fever and proportion of patients febrile each day after product A or B did not differ significantly. No differences were found in the frequency of coronary artery abnormalities 1 year after illness.

CONCLUSIONS

No significant differences in efficacy appeared between the two IVGG products, but they differed significantly in non-life-threatening adverse reactions, especially infusion-related rigors. Other IVGG products should be evaluated in a similar fashion.

Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.

Hepatocellular carcinoma: efficacy of transcatheter oily chemoembolization in relation to macroscopic and microscopic patterns of tumor growth among 100 patients with partial hepatectomy

PURPOSE

To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatocellular carcinoma (HCC) on the basis of microscopic and macroscopic findings postembolization.

METHODS

HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings: single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth type.

RESULTS

Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis) to the SNE type (21%), and the other types (9%).

CONCLUSION

TOCE appears to be most efficacious for HCC with the expanding growth pattern and HCC forming single nodules. Poor results are to be expected in HCC of replacing growth type and multinodular or massive growth types.

Dye-injection method for placement of an infusion catheter in regional hepatic chemotherapy

PURPOSE

To evaluate the usefulness of a dye-injection method in the placement of an infusion catheter and port via proximal branches of the axillary artery for hepatic infusion chemotherapy.

MATERIALS AND METHODS

Sixteen patients with surgically unresectable hepatic cancer underwent transfemoral hepatic arteriography. Then a 3-F coaxial catheter was inserted into a proximal branch of the left axillary artery. Dye injected through the coaxial catheter during the surgical procedure improved the visualization of the target branch. The coaxial catheter was also used as a guide for retrograde insertion through the target branch of an infusion catheter into the descending aorta.

RESULTS

In 13 of 16 patients (81%), catheterization was successful without exposure of the axillary artery. In these patients, the acromial-deltoid branch of the thoracoacromial artery was chosen as the target.

CONCLUSION

Injection of dye simplifies the surgical procedure for placement of a hepatic infusion catheter via proximal branches of the axillary artery. The depth and extent of incisions, as well as the risk of nerve injury, are reduced.

Developing a new picture archiving and communication system for the new Osaka University Hospital

Osaka University Hospital moved into a new hospital building on the suburban Suita campus in October 1993. A newly developed hospital information system, a new radiologic information system and phase I of a completely new Picture Archiving and Communication System (PACS) also began operating. Work began in 1986 on this PACS. The PACS effort has been guided by one working group and two committees during the last 7 years. A survey of the previous diagnostic and image delivery system was performed as part of the preamble to designing an optimal PACS. Extensive analysis and measurement of pre-existing operational conditions was undertaken. These studies and technical research projects are described in a companion paper in this issue. The phase I hardware installation and initial testing were completed in March 1994. Subsequent phases will build incrementally until the completely new, hospital-wide PACS is realized.

Initial data-element selection for the evaluation of picture archiving and communication system performance

The completely new, hospital-wide picture archiving and communication system (PACS) now being implemented at Osaka University Hospital is described elsewhere in this issue. This paper lists the many studies of the department and hospital that were performed before the PACS for the purpose of identifying data elements for use in evaluating a PACS system. A second purpose of the initial data-element collection was to assist in the overall Osaka University PACS design. Selected studies from this work are presented here.

A comparison of conventional screen-film radiography and hard copy of computed radiography in full and two-thirds sizes in detection of interstitial lung disease

This study examined whether hard-copy radiographs produced from computed radiography (CR) images show the subtle interstitial pulmonary disease equally well to conventional screen-film radiographs, because a digital radiography should be chosen for introduction of the digital picture archiving and communication system (PACS) for the new Osaka University Hospital. Eleven radiologists examined 20 abnormal and 20 control chest radiographs presented in each of three groups: conventional screen-film radiographs and two sizes of hard-copy radiographs made from CR images. This study of digital image quality of chest examinations found that some findings on conventional screen-film radiography images are not reproduced by current CR (2,000 x 2,000 x 10 bits in matrix), especially when the experienced radiologists were observed. This finding suggested improvements are needed in CR before CR of chest should fully replace conventional screen-film radiography.