| 摘要 |
<p>A negative contrast agent for MRI is an aqueous suspension having a quantity of barium sulfate between 25 and 40 percent by weight and a quantity of bentonite between two and four percent by weight. Such a negative contrast agent provides dark imaging in a T2 weighted pulse sequence; namely a relative signal intensity (RSI) approaching zero. It also provides a relative signal intensity (RSI) of under thirty percent of that of a reference that approximates tissue in a T1 weighted pulse sequence.</p> |
