TY - JOUR
T1 - Clinical significance of T1-weighted MR images following transient cerebral ischemia
AU - Aoe, Hisami
AU - Takeda, Yoshimasa
AU - Kawahara, Hidero
AU - Tanaka, Akio
AU - Morita, Kiyoshi
PY - 2006/2/15
Y1 - 2006/2/15
N2 - To try to determine the cause of hyperintensity of T1-weighted MR images that occurred on and after day 7 following transient cerebral ischemia, dynamic changes in T1-weighted images and histology of rats subjected to 20 min of 4-vessel occlusion were observed. T1-weighted images showed no remarkable alteration on days 1 and 3, although high signal intensity in the striatal region, in which the T1 value was significantly lower than the values on days 1 and 3, was observed on day 7. High signal intensity in T1-weighted images indicates low T1 values. Histological observation revealed accumulation of microglia in the striatal region on day 7 by lectin staining. There was a tight correlation between T1 values and number of lectin-positive cells. Microglia had stout processes and hypertrophic cell bodies on day 7, resembling lipid-laden phagocytes. Sudan black B staining showed the presence of many fatty droplets in the striatal region on day 7. Furthermore, double staining with lectin and Sudan black B revealed the presence of fatty droplets in bodies of lectin-positive cells on day 7. These results suggest that hyperintensity of T1-weighted images on day 7 following transient ischemia and reperfusion indicates accumulation and phagocytic activation of microglia. T1-weighted images seem to represent the progression of non-reversible tissue injury after transient ischemia and reperfusion.
AB - To try to determine the cause of hyperintensity of T1-weighted MR images that occurred on and after day 7 following transient cerebral ischemia, dynamic changes in T1-weighted images and histology of rats subjected to 20 min of 4-vessel occlusion were observed. T1-weighted images showed no remarkable alteration on days 1 and 3, although high signal intensity in the striatal region, in which the T1 value was significantly lower than the values on days 1 and 3, was observed on day 7. High signal intensity in T1-weighted images indicates low T1 values. Histological observation revealed accumulation of microglia in the striatal region on day 7 by lectin staining. There was a tight correlation between T1 values and number of lectin-positive cells. Microglia had stout processes and hypertrophic cell bodies on day 7, resembling lipid-laden phagocytes. Sudan black B staining showed the presence of many fatty droplets in the striatal region on day 7. Furthermore, double staining with lectin and Sudan black B revealed the presence of fatty droplets in bodies of lectin-positive cells on day 7. These results suggest that hyperintensity of T1-weighted images on day 7 following transient ischemia and reperfusion indicates accumulation and phagocytic activation of microglia. T1-weighted images seem to represent the progression of non-reversible tissue injury after transient ischemia and reperfusion.
KW - Basal ganglia
KW - Cardiopulmonary resuscitation
KW - Cerebral ischemia
KW - Magnetic resonance imaging
KW - Microglia
KW - T1-weighted images
UR - http://www.scopus.com/inward/record.url?scp=30944464200&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=30944464200&partnerID=8YFLogxK
U2 - 10.1016/j.jns.2005.10.013
DO - 10.1016/j.jns.2005.10.013
M3 - Article
C2 - 16386758
AN - SCOPUS:30944464200
VL - 241
SP - 19
EP - 24
JO - Journal of the Neurological Sciences
JF - Journal of the Neurological Sciences
SN - 0022-510X
IS - 1-2
ER -