[Magnetic resonance imaging of subarachnoid hemorrhage due to ruptured intracranial aneurysm].
We report MRI (magnetic resonance imaging) findings of 31 cases with subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysm. Among these cases, 25 were studied within 72 hours after onset of SAH. A resistive type MRI scanner operating at a field of 0.2 Tesla was used in obtaining inversion recovery (IR) and saturation recovery (SR) images. IR 1500/43/400 (T1 weighted image, T1W), SR 1000/60 (SR image) and SR 2000/100 (T2 weighted image, T2W) were chosen for analysis. The SR image was usually adopted and coronal and/or sagittal images were added when there was enough time for examination. Slice thickness was 10 mm and slice interval was 15 mm. The scan was not necessarily aimed at the visualization of aneurysm itself. 1) In the acute phase of SAH, subarachnoid spaces near the ruptured aneurysm were appeared as isointensity areas on T1W and as high intensity areas on SR image. In the subacute phase, they were depicted as high intensity areas on both T1W and SR images, and as high intensity areas on T2W. 2) Intraventricular hemorrhage was visualized as a niveau-like high intensity area, especially, within the posterior horns on the SR images. 3) SR and T2W images were suitable for detection of aneurysm itself. In a resistive-type scanner, small aneurysms were not easily visualized due to the lack of high resolution. However, 29% of aneuysms, which were not giant, could be visualized on MRI. 4) Identification of intracerebral hemorrhage and cerebral ischemia from various causes was easy on both T1W and T2W images.(ABSTRACT TRUNCATED AT 250 WORDS)
Yamagami
T
T
Department of Neurosurgery, Ijinkai Takeda General Hospital, Kyoto, Japan.
Higashi
K
K
Tashiro
Y
Y
Hashimoto
K
K
Minamikawa
J
J
Akiyama
Y
Y
Hashimoto
N
N
Kikuchi
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012422:Rupture, Spontaneous; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed