Published online before print February 19, 2003, 10.1148/radiol.2271020067
(Radiology 2003;227:124.)
A more recent version of this article appeared on April 1, 2003
Acute Cerebral Infarction: Effect of JPEG Compression on Detection at CT1
Yoshimitsu Ohgiya, MD,
Takehiko Gokan, MD,
Hiroshi Nobusawa, MD,
Masanori Hirose, MD,
Noritaka Seino, MD,
Hidefumi Fujisawa, MD,
Maiko Baba, MD,
Kyoko Nagai, MD,
Keisuke Tanno, MD,
Nobuyuki Takeyama, MD and
Hirotsugu Munechika, MD
1 From the Department of Radiology, Showa University School of Medicine, Tokyo, Japan (Y.O., T.G., H.N., M.H., N.S., M.B., K.N., K.T., N.T., H.M.); and Department of Radiology, Showa University Northern Yokohama Hospital, Japan (H.F.). From the 2001 RSNA scientific assembly. Received February 8, 2002; revision requested April 18; final revision received July 16; accepted August 29. Address correspondence to Y.O., Department of Radiology, Showa University School of Medicine, 1-5-8 Hatanodai Shinagawa-ku, Tokyo 142-0064, Japan (e-mail: yogiya@gd5.so-net.ne.jp).
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Figure 1a. Transverse CT images show acute cerebral infarction in the left insular cortex in a 72-year-old man. A small area of hypoattenuation (arrows) can be seen on (a) the noncompressed original image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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Figure 1b. Transverse CT images show acute cerebral infarction in the left insular cortex in a 72-year-old man. A small area of hypoattenuation (arrows) can be seen on (a) the noncompressed original image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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Figure 1c. Transverse CT images show acute cerebral infarction in the left insular cortex in a 72-year-old man. A small area of hypoattenuation (arrows) can be seen on (a) the noncompressed original image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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Figure 2a. Transverse CT images show acute cerebral infarction in the left middle cerebral artery area in a 72-year-old man.Obscuration of sulci (arrows) in the left temporal lobe can be seen on (a) the original noncompressed image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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Figure 2b. Transverse CT images show acute cerebral infarction in the left middle cerebral artery area in a 72-year-old man. Obscuration of sulci (arrows) in the left temporal lobe can be seen on (a) the original noncompressed image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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View larger version (114K):
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Figure 2c. Transverse CT images show acute cerebral infarction in the left middle cerebral artery area in a 72-year-old man. Obscuration of sulci (arrows) in the left temporal lobe can be seen on (a) the original noncompressed image and remains visible on (b, c) JPEG compressed images obtained at a ratio of 10:1 (b) and 20:1 (c).
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Copyright © 2003 by the Radiological Society of North America.
) and 10:1 (
) and 20:1 (
) JPEG compressed CT images used for the diagnosis of acute cerebral infarction. The diagnostic accuracy with images compressed at a ratio of 20:1 was slightly worse than that with noncompressed images, but the difference was not significant (P > .05).