Patterns of cerebral blood flow reactivity in adenosine stress-test in patients with carotid stenosis evaluated with MRI and emission tomography with 99m Tc-HMPAO

In this study we evaluated the adenosine stress-test combined with 99mTc-HMPAO SPECT as a possible tool for evaluation of brain perfusion reserve in patients with various degrees of cortical neurologic damage due to internal carotid artery stenosis. The investigation comprised 37 patients with atherosclerotic carotid disease, in everybody of whom the stenosis was detected by echo-Doppler study of carotids and later in 28 verified also using invasive intraarterial digital subtractive angiography. In everybody the 99mTc-HMPAO SPECT study was performed twice: at rest and during stress-test with intravenous injection of adenosine with the patient in the supine position. It was gathered three groups of patients with different kinds of cerebral blood flow reactivity in adenosine stress-test. Henceforth, we conclude that, first, the 99mTc-HMPAO SPECT adenosin stress challenge of cerebral blood flow is a reliable functional test for every group of patients with extensive atherosclerosis and can be used for detection of patients with exhausted or decreased cerebral perfusion reserve in whom the risk of future cerebral vascular ischaemic events is elevated.