Mutsumasa Takahashi

Transcatheter Arterial Chemoembolization of Renal Cell Carcinoma with Microencapsulated Mitomycin C

Ethylcellulose microcapsules of mitomycin C were prepared for intra-arterial use in an attempt to enhance the antineoplastic effects of mechanical arterial embolization. The potential therapeutic effects of intra-arterial mitomycin C microcapsules were considered to be a function of microembolization and prolonged drug action, that is chemoembolization. A total of 33 patients with renal cell carcinoma was subjected to transcatheter arterial chemoembolization with mitomycin C microcapsules supplemented with gelatin sponge, and 10 patients were subjected to chemoembolization with non-encapsulated mitomycin C and gelatin sponge. Comparative studies on objective tumor decrease, angiographical findings and histological effects between the 2 treated groups indicated that mitomycin C microcapsules definitely enhanced the therapeutic responses to gelatin sponge embolization. Bioassay of the peripheral blood revealed that intra-arterial mitomycin C microcapsules reduced markedly mitomycin C levels in the blood compared to non-encapsulated mitomycin C, leading to a decrease in hematological toxicity. The results may prove that chemoembolization with mitomycin C microcapsules is effective as a preoperative and palliative measure in the treatment of renal cell carcinoma.

Computed tomography of the paranasal sinuses and their adjacent structures

Forty-five computed tomographic examinations were performed on 34 patients with diseases of the paranasal sinuses and their adjacent structures. Coronal sections were obtained in addition to transverse axial tomographic sections. Evaluation was made whether CT could provide more informations compared with plain roentgenography and whether there were additional informations on coronal sections. CT showed soft tissue abnormality and its extension to better advantage. Especially, involvement of the orbits, pterygoid fossa, nasopharynx, skull base and brain were shown well. Coronal sections were useful in evaluation of superior and inferior extension of the tumors such as involvement of the superior and inferior orbital walls and skull base as well as intracranial extension. Since CT has the ability to better define the total extent of the lesion, this technique should be added to the conventional roentgenologic techniques preferably with the use of coronal sections.

Evaluation of therapeutic arterial embolization in renal cell carcinoma using microencapsulated mitomycin C

The therapeutic arterial embolization in the case of renal cell carcinoma using microencapsulated mitomycin C (MMC) was investigated by an angiographic evaluation in comparison with nonencapsulated MMC. The Gelfoam embolization supplemented with nonencapsulated MMC could not necessarily prevent the recanalization and collateral circulation, while the Gelfoam embolization supplemented with microencapsulated MMC completely or considerably eliminated the revascularization with a distinct advantage in this degree. Moreover, peripheral blood MMC level after the embolization using microencapsulated MMC was reduced to 39 per cent of that after nonencapsulated MMC infusion. The result was consistent with the previous experiments, indicating that the transcatheter infusion of microencapsulated MMC is the therapeutic arterial embolization of the tumor-supplying vessels together with regional anticancer chemotherapy. Further clinical application to various malignancies is in progress.

Metrizamide spinal computed tomography following myelography

Abstract Spinal computed tomography was performed following metrizamide myelography in five cases of spinal lesions. A metrizamide computed tomogram with myelogram revealed the extent of spinal tumors and disk herniation more precisely than a myelogram alone. In addition, syrinx of syringomyelia was demonstrated by sequential metrizamide computed tomography. This technique will play an essential role in the diagnosis of various spinal lesions.

Abdominal angiography with stereoscopic magnification.

A new technique for stereoscopic magnification angiography has been developed and combined with routine abdominal angiography. The technique utilizes two divergent x-ray beams at a 34° angle, with a 3.5 cm focal spot separation at a 94 cm focalfilm distance, produced by a synchronous arc rotation of a microfocus x-ray tube. The synchronous motion of the tube is maintained by using an electromechanical device. A magnification factor of 2.0 to 3.0 is used, and 12 films are exposed in a series, the fastest sequence being 1.5 films per second. This technique provides the advantages of magnification and stereoscopic angiography, with excellent demonstration of small arterial branches and abnormal vascularity in three dimensions.

Magnification angiography of dural carotid-cavernous sinus fistulae

SummaryEleven patients with dural carotid-cavernous sinus fistulae were studied with selective magnification angiography. The angiographic features of this condition were analyzed in detail. The arterial plexus normally present in and around the cavernous sinus has been thought to rupture into the sinus and establish an arteriovenous fistula with an extensive dural arterial supply. Changeable angiographic and clinical findings, including spontaneous regression, can be explained on the basis of thrombosis and occlusion in the arterial network. The indications for and methods of embolization are also discussed.