| Summary: | 博士 === 國立臺灣大學 === 電機工程學研究所 === 94 === Pulmonary perfusion is a fundamental parameter of lung function, since matched distribution of the regional pulmonary blood flow and ventilation is a prerequisite for gas exchange to occur efficiently. Radionuclide techniques using intravenous administration of radioactive macroaggregates have been used for the clinical assessment of regional lung perfusion. Recently, magnetic resonance imaging has become feasible using ultra-short echo time sequence. In this thesis, we present recent advances in magnetic resonance pulmonary perfusion imaging, including magnetic resonance perfusion imaging using gadolinium contrasts agents (CE-MRI) or spin labeling of blood using naturally flowing spins as the source of intravascular signal (ASL). First, we apply flow-sensitive alternating inversion recovery (FAIR) and CE-MRI techniques in normal subjects, and demonstrate that FAIR imaging for pulmonary perfusion in the coronal plane provides equivalent rPBF information with CE-MRI only in the absence of tracer saturation effects, hence, FAIR should be carefully exercised to avoid misleading interpretations. Second, we show that discrepancy exists between lung perfusion scintigraphy (PS) and CE-MRI, resulted from the abnormal flow dynamic in patients with complex cardiovascular circulation such us patients with congenital heart diseases. A remedy using limited integration has been proposed, which provides consistent perfusion result as PS. We conclude that CE-MRI is facilitate in pulmonary perfusion and has significant potential for clinical use.
|
|---|
