Radiology, Vol 196, 773-777, Copyright © 1995 by Radiological Society of North America
Acute subarachnoid hemorrhage: MR imaging with fluid-attenuated inversion recovery pulse sequences
K Noguchi, T Ogawa, A Inugami, H Toyoshima, S Sugawara, J Hatazawa, H Fujita, E Shimosegawa, I Kanno and T Okudera
Department of Radiology, Research Institute of Brain and Blood Vessels- Akita, Japan.
PURPOSE: To evaluate the usefulness of fluid-attenuated inversion recovery
(FLAIR) magnetic resonance (MR) imaging sequences in the detection of acute
subarachnoid hemorrhage (SAH). MATERIALS AND METHODS: MR imaging with FLAIR
sequences was performed with a 0.5-T superconducting unit in 20 patients
(aged 30-72 years) with acute SAH due to a ruptured aneurysm and in 27
control subjects (aged 32-72 years). FLAIR images were obtained 2 hours to
2 days after ictus. Findings were evaluated and compared with computed
tomographic (CT) findings. RESULTS: In all patients, acute SAH was clearly
demonstrated as an area with signal intensity that was high relative to
that of the normal cerebrospinal fluid and surrounding brain parenchyma at
FLAIR imaging. This sequence was especially useful in demonstration of
acute SAH in the posterior fossa, which was difficult to show at CT because
of beam-hardening artifacts. In a double-blind comparison, no FLAIR images
acquired in control subjects were confused with those acquired in control
subjects were confused with those acquired in patients. CONCLUSION: FLAIR
sequences reliably provide diagnostic images in patients with acute SAH.
