Hiroyasu Yoshioka

Struma ovarii: CT and MR findings.

A case of pure struma ovarii is reported with its CT, magnetic resonance (MR), and pathologic findings. Both MR and CT revealed a complex mass composed of solid elements and multiple cysts; CT revealed calcifications not apparent on MR.

Comparison between conventional and spiral CT in patients with hypervascular hepatocellular carcinoma

To determine the usefulness of spiral CT in the detection of hypervascular hepatic lesions, we compared conventional contrast enhanced CT (CECT) with whole liver dynamic scanning during the artery-dominant phase by spiral CT (SDCT), using hypervascular hepatocellular carcinoma (HCC) as a model. Twenty-nine patients with 56 hypervascular nodular type HCCs detected by hepatic digital subtraction angiography were examined by both CT techniques. These nodular type HCCs were divided into three groups according to diameter: < 10 mm (n = 7), 10-20 mm (n = 17), and over 20 mm (n = 32). None of seven lesions less than 10 mm in diameter was seen by either technique. Of 17 lesions 10-20 mm in diameter, four (24%) were detected by precontrast CT plus CECT, whereas 14 (82%) were detected by precontrast CT plus SDCT. There were no lesions detected by CECT only, whereas 10 lesions were detected by SDCT only (P < 0.01 by signed test). For 32 lesions over 20 mm in diameter, there was no significant difference in detection rates between the CT techniques. Our results indicate that spiral CT is useful for the detection of relatively small hypervascular hepatic lesions such as hypervascular HCCs.

CT findings in «pseudoalveolar» sarcoidosis

To determine the specific high resolution CT (HRCT) features for “pseudoalveolar” sarcoidosis, we reviewed HRCT of 10 patients with pathologically proven sarcoidosis. On HRCT the lesions of pseudoalveolar sarcoidosis were shown as homogeneous or inhomogeneous opacities 1–4 cm in diameter located either along the bronchovascular bundles or in the lung periphery adjacent to the pleural surface. The margin was irregular, and numerous nodules 1–2 mm in diameter were observed in the surrounding lung. Air bronchograms were observed in 6 patients. In addition to these lesions, other CT abnormalities such as nodules, groundglass opacities, thickened bronchovascular bundles, and interlobular septa were found in all 10 cases. Good response of pseudoalveolar sarcoid lesions to administration of corticosteroid was observed in all three cases in which follow-up CT was available.

MAGNETIC RESONANCE IMAGING-HISTOLOGIC CORRELATION OF SMALL HEPATOCELLULAR CARCINOMAS AND ADENOMATOUS HYPERPLASIAS

RATIONALE AND OBJECTIVES.Hepatocellular carcinomas (HCCs) usually consist of components of different histologic grade. Using surgically resected specimens, the authors obtained high-resolution magnetic resonance (MR) images and studied the relationship between histologic grade of HCCs and MR signal intensity. METHOD.In vitro MRI was performed on 15 small (less than 20-mm diameter) HCCs and 2 patients with adenomatous hyperplasia (AH) within 1 hour of surgical resection. In these 17 lesions, 24 macroscopic nodular components corresponding to MR images were recognized pathologically. The difference in MR signal intensity was examined by using tumor/phantom (T/P) signal-intensity ratio. In addition, the correlations between signal intensity on MRI and histologic criteria for grading HCC were studied. RESULTS.On T2-weighted images, grade II HCCs had significantly greater T/P values than grade I HCCs (P < .01). There is the correlation (r = .88, P < .001) between nucleocytoplasmic (N/C) ratio and signal intensity of small HCCs and AHs on T2-weighted images. CONCLUSION.The N/C ratio is an important factor relating the signal intensity to the histologic grade of these lesions on T2-weighted images.

Small PACS for digital medical images - reliability and security in a clinical setting

Recently we introduced a small Picture Archiving Communication System (PACS) for handling CT and MRI data. Our experience with this system has been useful in identifying potential problems in a clinical setting. Since the use of PACS raises both medical and social concerns, it cannot be instituted without addressing concerns related to the reliability and security issues. Although PACS is useful in the management of medical images, there are concerns about their reliability and security in a clinical setting. Reliability encompassed image quality, timeliness of the reports, and the PACS to the Radiological Information System (RIS) interface including the retrieval of the previously obtained images. The security of the patients medical data is also essential.

Clinical trials of intrasplenic arterial infusion of interleukin-2 (IS-IL-2) to patients with advanced cancer

We tried a infusion of interleukin-2 (IL-2) of a relatively low dose via an intrasplenic arterial catheter connected to a chronometric infusion (IS-IL-2). Eighteen patients of colorectal cancer with metastases to the liver or lung or of unresectable hepatoma received a 24 hour continuous infusion with low dose recombinant of IL-2 (mainly 8 × 105 JRU/day) for 25–40 days. All patients tolerated this protocol of the therapy and the main toxic effects were fever and general fatigue. Such serious toxicity as previously reported by high dose IL-2 therapy was not observed. Data of hepatic and renal functions were normal. IS-IL-2 therapy induced a high incidence of eosinophilia (12/18) and thrombocythemia (12/18). Peripheral natural killer (NK) and LAK activities were augmented in all patients and total white blood cell counts were increased during IS-IL-2 therapy. An increase in IL-2 receptor expression of peripheral blood mononuclear cells and significant rises in numbers of Leull (CD16)+, OKMl(CD11)+ and OKIal(HLA-DR)+ were observed. Of 18 patients 12 were evaluable for their response to therapy. Partial response (PR) was observed in one unresectable hepatoma and 11 demonstrated no change (NC) or progressive disease (PD). Six patients were not evaluable because of additional therapy (3 cases) or decreasing tumor cell markers having no measurable lesions (3 cases). Three patients of colorectal cancer from an unresectable group were presumed to have micrometastases to the liver as suggested by an elevated serum CEA level. After receiving IS-IL-2 therapy they demonstrated a decrease in the serum CEA level for more than 3 years after treatment. We conclude that continuous IS-IL-2 administration can result in an increase of their therapeutic efficacy of IL-2 administration and in a decrease its toxicity.

P-31 MR spectrum and histologic changes after intrahepatic arterial injection of iodized oil in normal and cirrhotic rat liver

Injection of iodized oil (Lipiodol) into the hepatic artery is widely used in the diagnosis and treatment of hepatocellular carcinoma. However, no reports have yet appeared concerning temporal changes in hepatic metabolism following Lipiodol injection. In the present study, Lipiodol was injected into the hepatic arteries of normal and cirrhotic rats, successive P-31 MR measurements were performed, and temporal changes in metabolism were compared with histologic findings. Both normal and cirrhotic rats displayed minimum levels of β-ATP/PME and β-ATP/Pi 5 days after hepatic arterial injection of Lipiodol. However, 10 days after injection these values had reverted to the preinjection levels. The metabolic dysfunction observed in the liver following hepatic arterial injection of 0.3 ml/kg b.w. Lipiodol was transient. Moreover, no distinct differences were observed between P-31 MR changes in normal and cirrhotic rats. Conversely, histologic impairment assessed on the basis of hepatic necrosis ratios was most severe 2 days after hepatic arterial injection in both normal and cirrhotic rats, and this did not coincide with the time of the most pronounced metabolic impairment as inferred from P-31 MR changes.