Kazuhiro Yoshizumi

Prognostic factors in the treatment of hepatocellular carcinoma with transcatheter arterial embolization and arterial infusion

From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy‐five patients were included. Okudas staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti‐cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti‐cancer agent (protocol 1b); or iodized oil mixed with an anti‐cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti‐cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.

Value of dynamic susceptibility contrast magnetic resonance imaging in the evaluation of intracranial tumors.

The degree of tumor malignancy generally correlates to tumor grade, and the direct measurement of tumor vasculature is desired. Dynamic susceptibility contrast magnetic resonance imaging can provide relative cerebral blood volume and, therefore, is one of the most reliable methods to evaluate tumor vasculature in vivo. Tumor vessel size is extremely variable due to complex tumor angiogenesis, and the gradient-echo echo-planar imaging (GE-EPI) technique, which is sensitive to the total vascular bed, is well suited for this purpose. As many studies have shown, dynamic susceptibility contrast magnetic resonance imaging is more useful for grading glioma than conventional magnetic resonance imaging. We found that this technique can also provide supplementary information to differentiate between malignant lymphoma and glioma because the absence of tumor neovascularization of malignant lymphoma leads to low rCBV, which is in contrast to those of malignant gliomas. Indeed, this technique can be used for the differentiation of extra-axial tumors such as between meningioma and neurinoma. Recently, this technique has been focused toward determining the stereotactic biopsy site, monitoring the embolization of effect in meningioma, or evaluation of treatment effects after radiation therapy. However, the value of tumor rCBV is affected by many conditions such as the T1 relaxivity effects of gadolinium in the extravascular space. To establish the usefulness of this technique, further examination will be needed.

Radiation therapy of invasive thymoma

Between 1978 and 1987, 30 cases of invasive thymomas were treated with radiotherapy after surgery. Surgical therapy consisted of total resection in 15 patients, subtotal resection in 1 patient, and biopsy in 14 patients. Myasthenia gravis (MG) was associated in nine patients (MG(+) group), but in 21 patients there was no evidence of myasthenia gravis (MG(-) group). Irradiation in the dose range of 30 to 58.7 Gy was delivered. The total average 5-year survival rate was 71.8%; it was 39.2% in MG(+) group and 78.3% in MG(-) group, though there was no significant statistical difference. Myasthenia gravis was well controlled by the tumorectomy and associated radiotherapy in 7 of the 9 patients. However, in 3 of 7 patients (42.9%) myasthenia gravis recurred at 2 years, 2 years and 7 months, and 5 years and 8 months after initial therapy. Total body irradiation of 2 Gy with 0.1 Gy fractions was administered for uncontrollable myasthenia gravis in one patient with marked improvement. Radiation therapy is an important therapeutic modality for unresectable malignant thymoma as well as for postoperative combined therapy. Total body irradiation may be an effective method to treat patients with otherwise resistant myasthenia gravis.

MRI findings of hypothalamic hamartoma : Report of five cases and review of the literature

Hypothalamic hamartoma is a relatively rare congenital malformation, associated with the clinical presentation of precocious puberty of central type. Five cases with hypothalamic hamartoma are reported here, with an emphasis on MR appearance. The most common presentation of hypothalamic hamartoma was a small and well defined mass in the inferior aspect of the hypothalamus, showing isointensity on T1 weighted images and hyperintensity on T2 weighted images compared with the gray matter. The previous reports with MRI description are reviewed and compared with the present results.

Three cases of spinal dural AVF: Evaluation with first-pass, gadolinium-enhanced, three-dimensional MR angiography

A first‐pass, contrast‐enhanced three‐dimensional (3D) magnetic resonance (MR) angiography with short acquisition time was performed for three consecutive cases with suspected spinal arteriovenous fistula (AVF). This MR technique demonstrated the feeding arteries and draining veins of the spinal dural AVF, and was very useful for the definite diagnosis of the lesions as a disease with arteriovenous shunt. With this MR technique, we could localize the feeding artery and shunt before conventional angiography. J. Magn. Reson. Imaging 2000;12:949–952.

Prognostic factors in liver metastases after transcatheter arterial embolization or arterial infusion.

From January 1986 to December 1988, 85 patients (55 men and 30 women, mean age 59 years) with metastatic liver tumors were treated with hepatic artery embolization (TAE) or infusion (HAI). Sixty-eight patients with successful catheterization were treated with TAE using iodized oil (Lipiodol) mixed with anticancer agent (ACA). In 12 of 68 patients with hypervascular tumors gelatin sponge was added. Patients with unsuccessful catheterization were treated with hepatic artery infusion of ACA. Forty-three patients received oral chemotherapy following TAE or HAI. Overall, the 6-month, and 1- and 2-year survival rates were 69.5, 31.8 and 4.1 per cent, respectively (mean 233 days). A univariate analysis of prognostic factors showed that number of metastases, stage, treatment times and oral chemotherapy were all significant factors (p<0.05). Ascites, jaundice, percentage of hepatic replacement and treatment protocol also had some influence (p<0.1). Sex, age, primary site, elevation of tumor markers, other metastatic lesions, portal vein involvement and difference in anticancer agent had no prognostic significance. A multivariate analysis using Coxs proportional hazard model revealed that the number of treatments had the most important prognostic significance, followed by oral chemotherapy, stage and percentage of hepatic replacement.

Skull base tumors: evaluation with contrast-enhanced MP-RAGE sequence

The purpose of this study is to assess the value of contrast-enhanced MP-RAGE sequence for evaluation of skull base tumors. A total of 36 patients were prospectively evaluated. MP-RAGE showed relatively higher CNRs than other sequences, and there was a significant difference of CNR between the MP-RAGE and contrast T1-weighted SE images when fat tissue was chosen as the background. MP-RAGE was significantly superior to other sequences in the diagnosis of the extent of tumors. Contrast-enhanced MP-RAGE sequence is useful in evaluation of skull base tumors because of its higher contrast, higher spatial resolution, multiplanar capability, and suppression of the fat signal.

MRI evaluation of sequential changes of the injured spinal cord

Thirty-seven cases of acute spinal cord injury were studied with MRI and correlated with the neurological findings. Nineteen out of 37 cases were followed by sequential MRI for 10 days to 1 year. Cord abnormalities, including cord compression, cord swelling, and abnormal signal intensities were observed on the initial MR images, followed by various changes, depending on the nature of the initial damage on the subsequent MR images. The most frequent initial changes within the cord included isointensity on both T1- and T2-weighted images or isoin-tensity on T1-weighted images and hyperintensity on T2-weighted images, followed at 2 months by persistence of isointensity on T1-weighted images and hyperintensity on T2-weighted images. The most common final MR appearance was hypointensity on T1-weighted images and hyperintensity on T2-weighted images. The size of the hyperintense area on T2-weighted images was the most important finding in predicting the prognosis of spinal cord injuries.

Intracranial and Cervical Three-Dimensional Computed Tomography Angiography Using a Multislice Computed Tomography System: Initial Clinical Experience

After the introduction of a new multislice computed tomography (MSCT) scanner, it has become possible to produce high-speed CT angiography (CTA) of high quality for the intracranial and cervical vessels. In our initial experience, 66 consecutive patients with known or suspected carotid and/or intracranial arterial lesions underwent CTA using a MSCT scanner. Three scanning techniques were adopted for 1. high-speed CTA covering both cervical and intracranial vessels; 2. high-quality intracranial imaging and high-speed cervical imaging with double injection of contrast materials; and 3. high-quality CTA for intracranial vessels. A total of 90-105 ml of contrast material (300 mgI, non-ionic) was injected at a rate of 3 ml/s using a power injector. With a MSCT scanner, three-dimensional (3D) CTA images of excellent quality were obtained in all cases without overlapping of cavernous sinuses and intracranial veins because of shorter acquisition time. Approximately 25 cm of scanning extent, enough to cover from the carotid bifurcation to distal cerebral arteries, could be obtained in 16 s with good image quality. In the visualization of small branches, high-speed CTA of high quality was equivalent to intra-arterial digital subtraction angiography (IADSA) and superior to magnetic resonance angiography. The MSCT scanner can provide 3D CTA of excellent quality with significantly shorter acquisition time in the intracranial and cervical regions.

Comparison of MRI, CT and myelography in the diagnosis of lumbar disc disease

The records of 96 herniated lumbar discs of 94 patients were retrospectively analysed as to the diagnostic accuracy of MRI, myelography and CT myelography. Myelography and CT myelography were able to show certain associated findings, especially nerve root compression, but overall diagnostic accuracy of MRI was better than that of myelography and CT myelography.