Prediction of recurrence after HCC resection. Faint oily deposits on preoperative Lipiodol-CT of remnant liver tissue.

In trying to clarify the high recurrence rate after removal of small hepatocellular carcinoma (HCC), we assessed the postoperative evolution of minute hepatic Lipiodol deposits which had been diagnosed as artifacts on the preoperative Lipiodol-CT. Of 27 patients with solitary HCC less than 5 cm in diameter, 14 had such Lipiodol deposits in the preoperative CT and 9 of them (64%) developed recurrent tumors. On the other hand, 6 of the 13 patients without deposits (46%) suffered recurrence, but in 5 of these 6 patients the HCC was metachronous multicentric. The cumulative survival rate of the non-deposit group was better than that of the deposit group (p < 0.1). The present study suggested that, even in patients with small HCC, minute concomitant tumors invisible by conventional imaging techniques may exist at the time of surgery. Some of these lesions without sufficient tumor vasculature showing a hypervascular blush on angiography appear to retain small, vague Lipiodol deposits.

Amyotrophic lateral sclerosis: T2 shortening in motor cortex at MR imaging.

PURPOSE: To determine whether decreased signal intensity of the motor cortex (T2 shortening) at magnetic resonance (MR) imaging is a useful finding for supporting the diagnosis of amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS: High-field-strength (1.5-T) MR images of 15 patients (seven men and eight women, aged 28-80 years) and 49 neurologically normal age-matched control patients were examined for T2 shortening in the motor cortex. In addition, brains of patients with ALS were examined at autopsy. RESULTS: The MR images of 14 of the 15 patients showed T2 shortening in precentral cortices, while the images of all but one of the control patients showed no such finding. In three of eight brains at autopsy, sections from the precentral cortex showed sparsely distributed, intensely stained astrocytes and macrophages. CONCLUSION: Abnormal iron deposition associated with the degenerative process could be the source of T2 shortening, which is a useful MR imaging finding in the diagnosis of ALS.

Dense parenchymal accumulation of Lipiodol after transarterial chemoembolization.

Dense accumulation of Lipiodol in hepatic segmental parenchyma was studied by computed tomography (CT) after transarterial chemoembolization (TACE) for hepatic tumor. Six patients showed dense accumulation of Lipiodol in hepatic segmental parenchyma on CT two weeks after TACE. Four of the six showed parenchymal accumulation of Lipiodol as dense as that in a tumor at three weeks after TACE. Therefore, it was considered that evaluation with CT should be performed after one month or more in order to differentiate between Lipiodol accumulation in tumors and that in non-neoplastic liver parenchyma.

[MR imaging of amyotrophic lateral sclerosis].

Magnetic resonance imaging (MR imaging) provides a sensitive method for mapping the normal and pathological distribution of iron in the brain. High field strength MR imaging (1.5 T) was used to evaluate eight patients with amyotrophic lateral sclerosis (ALS) and 49 neurological normal control patients. All eight ALS patients showed decreased signal intensity in the motor cortex on T2-weighted images, while only one of the normal control patients showed this finding. The results suggested that the decreased signal intensity in the motor cortex in ALS was caused by the deposition of iron in this area.

Exophytic regenerating nodule of the liver: misleading appearance on iodized-oil CT.

Iodized-oil CT in a patient with chronic liver disease revealed focal accumulation of iodized oil in an exophytic mass. Single photon emission CT (SPECT) with [99mTc]phytate showed the existence of functioning Kupffer cells, excluding hepatocellular carcinoma. Biopsy revealed a regenerating nodule. Positive iodized-oil CT does not always indicate hepatoma. In such cases, SPECT with [99mTc]phytate will help to make a correct diagnosis.

Newly developed transarterial chemoembolization material: CDDP-lipiodol suspension.

Cis-Diamminedichloroplatinum (CDDP)-lipiodol suspension (CLS) was developed as a transarterial chemoembolization (TACE) material. The CLS was injected into the proper hepatic artery or distal branches of patients with hepatocellular carcinoma. Strong anticancer effects were observed. Plasma concentrations of total and filtrable CDDP following TACE were much lower than those following intravenous administration of CDDP solution. No major adverse complications were noted, presumably due to low CDDP concentrations in circulating plasma. The CLS appears to be an excellent TACE material.

Detection of mutagenic activity in automobile exhaust.

Using the Ames Salmonella-microsome system, we detected mutagenic activity in the exhaust from two kinds of 4-cycle gasoline engines of unregulated and regulated cars, and from diesel engines, as well as in the particulates from air collected in tunnels. The mutagenicity of particulates from a car equipped with a catalyst (regulated car), as compared with that from an unregulated car, was reduced very much (down to 500 from 4500 revertants/plate/m3 in tester strain TA98). However, the mutagenicity of the ether-soluble acid and neutral fractions from the condensed water of emissions from a regulated car was still high (down to 2880 from 10 900 revertants/plate/m3 in tester strain TA100). The mutagenic activity of emission exhaust from old diesel car engines was very high; the particulates showed 9140 and 19 600 revertants/plate/m3 from strain TA98 incubated with an activating rat-liver S9 fraction. A small diesel engine of the type used for the generation of electric power or in farm machinery also produced exhaust with highly mutagenic particulates. The mutagenic activity of a methanol extract of particulate air pollutants collected in a highway tunnel showed 39 revertants/plate/m3 toward strain TA98 and 87 toward strain TA100. The ether-soluble neutral fraction yielded 86 revertants/plate/m3 from strain TA98 and 100 from strain TA100. This fraction also contained carcinogenic compounds, including benzo[a]pyrene, benzo[e]pyrene, benz[a]anthracene, benzo[ghi]perylene and chrysene. Very high mutagenic activity was detected, especially in the particulate air pollutants collected at night, in another tunnel on a superhighway: 60-88 revertants/plate/m3 from strain TA100 for the sample collected by day, but 121-238, by night. Night traffic includes many more diesel-powered vehicles compared with gasoline-powered automobiles.