正常腦下垂體在正中矢狀面的磁振斷層影像：其信號強度和其T1，T2值

The Normal Pituitary Gland: Its Relative Signal Intensity in the Midline Sagittal MRI Study and Its T1 and T2

鄧木火(Michael Mu-Huo Teng)

《中華放射線醫學雜誌》 10卷1期 (1985/03) Pp. 19-26

摘要

本研究探討正常腦下垂體在旋轉回波(spin echo)的磁振斷層影像(magnetic resonance imaging)在下列不同的波間間隔(interpulse time)變化：TR300mSec/TE30 mSec（25例），TR300mSec/TE60 mSec（15例），TR1500mSec/TE30mSec（20例），及TR1500mSec/TE120mSec（20例）之下，在正中矢狀面上的信號強度，並以其與同平面上各常見組織之信號強度作比較。其中5例並量取各組織之信號強度，直接代入而在SE300/30用SE1500/30求取腦下垂體－腦灰質／腦白質－腦灰質之值，在SE1500/120求取腦下垂體－腦灰質／腦脊液－腦灰質之值。再分別計算每例各組織之T1，T2及旋轉質子密度(ρ)。
在SE300/30，SE1500/30，SE1500/120三種常用影像下，正常的腦下垂體信號強度約介於灰質與白質之信號強度間。而其T1值亦介於灰質與白質之T1間。T'2值則可略大於灰質之T2，如計算腦下垂體T2-灰質T2／腦脊液T2-灰質T2，其值最大為182。
以直接量得之信號強度計算，在SE300/30，腦下垂體－腦灰質／腦白質－腦灰質之值為0.76~1.93；在SE1500/30，腦下垂體－腦灰質／腦灰質－腦白質之值為-0.39~+2.6；在SE1500/120，腦下垂體－腦灰質／腦白質－腦灰質之值為0.21~0.57。

並列摘要

In order to understand the signal intensity of the normal pituitary gland in various images of MRI study with these interpulse time changes: TR 300 mSec/TE 30 mSec, TR 300 mSec/TE 60 mSec/TE 60 mSec, TR 1500 mSec/TE 30 mSec, TR 1500 mSec/TE 120 mSec, cases of MRI studies with normal pituitary gland were reviewed. The signal intensity of the pituitary gland were compared with those of other tissues in the same image with eyes directly. The pixel value of signal intensity of these tissues in five of these cases are measured to calculate the ratio of (pixel value difference between the pituitary gland and gray matter) to (the pixel value difference between gray matter and white matter) on SE 300/30 and SE 1500/30. On SE 1500/120, the ratio of (the pixel value difference between the pituitary gland and gray matter) to (the pixel value difference between CSF and gray matter) were calculated. Then T1, T2 and proton density of these five cases are calculated.
The signal intensity of normal pituitary gland are between those of white matter and gray matter in these most useful diagnostic images of SE 300/30, SE 1500/30, and SE 1500/120.
The ratio of (the pixel value difference between pituitary gland and gray matter) to (the pixel value difference between white matter and gray matter) ranges from 0.76 to 1.93 on SE 300/30. The ratio of (the pixel value of pituitary gland-the pixel value of gray matter) to (the pixel value of gray matter-the pixel value of white matter) ranges from -0.39 to+2.6 on SE 1500/30. The ratio of (the pixel value of pituitary gland-value of gray matter) to (the value of CSF-the value of gray matter) ranges from 0.21 to 0.57 on SE 1500/120.
T1 of normal pituitary gland are between those of gray matter and white matter in all these five cases. The ratio of (T2 of pituitary gland-T2 of gray matter) to (T2 of CSF-T2 of gray matter) ranges from 0 to 18% in these five cases.
These observations are made on midline sagittal views obtained from a 0.35 Telsa Siemens Superconductive magnetic resonance imager (Magnetom). The thickness of each image is 10mm.