腎癌におけるLarge Volume Renal Arteriography - その適応について -

Abstract

腎癌の症例21例を対象に, 腎静脈病変の診断を目的としてlarge volume renal arteriography (LVRAG)をおこなった.1) LVRAGによる腎静脈腫瘍塞栓の正診率は76%, 誤診率は24%であった.誤診はすべてfalse positiveであった.2) LVRAGによる腎静脈の造影の良否は, 残存実質量の多寡に大きく影響される.3)残存実質量比が0.5以上保たれている場合には, 比較的小さい腫瘍(10 cm×10 cm以下)を有する症例や, 巨大な腫瘍でもvascularityの低い腫瘍を有する症例では, 腎静脈が開存していれば, LVRAGによって良好な腎静脈像を得ることが可能で本法の良い適応となる.4)残存実質量比が0.5未満の症例では, たとえ腎静脈が開存していても, 腎静脈の描出は不良となり, LVRAGにてfalse positiveとなる場合が多く, 判定上注意を要する.総造影剤量制限を考慮すると, このような症例にLVRAGをおこなうことは造影剤の浪費となってしまう可能性が大きいので, 本法は適応しない方が良い

Between April 1980 and June 1982, 21 patients with renal cell carcinoma underwent large volume renal arteriography (LVRAG) to examine the involvement of the main renal vein. Angiographic interpretations were compared with surgical or autopsy findings in all cases. This paper reports the accuracy of L VRAG in predicting the involvement of renal vein and analyzes the factors that affect the opacification of renal vein on 17 cases proved to be Vo. We discuss the limitations and indications of this method. In 16 cases (76%) the diagnosis of renal vein involvement on L VRAG was verified to be correct at surgery or autopsy. The remaining (5 cases, 24%) were all false positive cases. The major factor affecting the opacification of the renal vein was the residual volume of the parenchyma of involved kidney. We estimated the volume of residual renal parenchyma by the ratio residual parenchymal volume/parenchymal volume of contralateral kidney. Volume of renal tissue was measured by computer tomography. When the ratio was over 0.5, dense opacification of patent main renal vein was always obtained. The indication of L VRAG was good in such cases. In those cases with less preservation of the parenchyma we could not obtain satisfactory opacification of renal vein in spite of its patency. Taking the dosage limit of contrast medium into consideration, L VRAG is not a good indication in such cases.