[Measurement of cerebral blood flow with 99mTc-ECD SPECT and its potential clinical implications--analyzing the relationships between CBF and lifestyle disease].

The Patlak plot method of measuring cerebral blood flow (CBF) to improve the repeatability and quantitative capability, by using technetium-99m ethyl cysteinate dimer (99mTc-ECD). We calculated CBF and then statistically analyzed its relationships with various hematological and biochemical parameters. There were significant statistical correlations between these clinical parameters and the measured values of mean CBF (mCBF), also between these biochemical parameters and post-acetazolamide (p-ACZ) mCBF, in terms of estimated glomerular filtration rate (eGFR), serum albumin level, red blood cell count, blood urea nitrogen level, and random blood glucose level. In addition, statistically significant correlations were found between these parameters and increased mCBF. Another significant correlation was found between cerebrovascular reserve capacity (CVR) and platelet count. Values of p-ACZ mCBF and CVR were lower in a group with HbA(1C) >7% and high blood glucose levels than in healthy subjects. In addition, values of resting mCBF and p-ACZ mCBF were lower in a group with kidney dysfunction (eGFR <30 ml/min/1.73 m2) than in subjects with normal renal function or mild dysfunction. A multiple linear regression analysis showed a correlation between resting mCBF value and eGFR. Therefore, there were correlations between CBF and the levels of these parameters of diabetes or chronic kidney disease. These results suggest that our Patlak plot modified method may be a potentially useful tool for analyzing the relationships between CBF and underlying diseases and/or the pathophysiology of CBF dysfunction. The post-ACZ ECD Patlak resting and vascular reserve (p-ACZ ECD Patlak RVR) test provides a way of detecting minor changes in CBF, which is difficult to reveal by only resting Patlak plot method, in patients with lifestyle diseases such as diabetes or chronic kidney disease. In addition, we believe that a new modified method contribute to predict risk of cerebral vascular disorders along with clinical parameters.