抄録
The possibility of measuring the rCBV with CT-scanner, proposed by several authors, was based upon the assumption that extravasation of the contrast medium does not occur within 1 hour after intravenous administration if the blood-brain-barrier is intact. They have estimated the absolute value of rCBV in different slices of CT-scan by subtraction method. However, some authors have criticized the method itself and pointed out several technical disadvantages as well as the causes of failure.
We had opportunity to examine the rCBV with CT-scanner according to Ladurner's method and found that the estimated values showed significant aberrations. This made us to conclude that the enhancement value after the administration of contrast medium is should reflect the relative amplitude of the rCBV. In order to compare the relative value of rCBV of specified region with other cerebral area, for instance, contralateral corresponding area, a computer programming was established and applied to clinical investigation, especially in the cases of cerebrovascular diseases. Results obtained were as follows;
1) In Moya-Moya disease, rCBV in the site of lesion, was significantly less than the value of contralateral region. Although the patients showed neurological symptoms and signs due to ischemic process the CT-scan appeared within normal.
2) In patients with TIA's there was a consistent tendency that rCBV in the affected region was slightly larger than that of corresponding region. The TIA's might be attributed to sudden drops of increased rCBV at the site of lesion.
3) In patients with fresh cerebral infarction, rCBV surrounding the low density area of CT-scan was larger than that of corresponding area. As a possibility luxurious perfusion of the affected area was suspected.
4) The experimental works with 3 Japanese monkeys showed analogous change of rCBV to the clinical observation when acute cerebral infarction of the monkey was successfully established.