Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-der...Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI.展开更多
OBJECTIVE： To identify global research trends in neuroimaging diagnosis for cerebral infarction using a bibliometric analysis of the Web of Science. DATA RETRIEVAL： We performed a bibliometric analysis of data retri...OBJECTIVE： To identify global research trends in neuroimaging diagnosis for cerebral infarction using a bibliometric analysis of the Web of Science. DATA RETRIEVAL： We performed a bibliometric analysis of data retrieval for neuroimaging diagnosis for cerebral infarction containing the key words ＂CT, magnetic resonance imaging, MRI, transcranial Doppler, transvaginal color Doppler, digital subtraction angiography, and cerebral infarction＂ using the Web of Science. SELECTION CRITERIA： Inclusion criteria were： （a） peer-reviewed articles on neuroimaging diagnosis for cerebral infarction which were published and indexed in the Web of Science; （b） original research articles and reviews; and （c） publication between 2004-2011. Exclusion criteria were： （a） articles that required manual searching or telephone access; and （b） corrected papers or book chapters. MAIN OUTCOME MEASURES： （1）Annual publication output; （2） distribution according to country; （3） distribution according to institution; （4） top cited publications; （5） distribution according to journals; and （6） comparison of study results on neuroimaging diagnosis for cerebral infarction. RESULTS： Imaging has become the predominant method used in diagnosing cerebral infarction. The most frequently used clinical imaging methods were digital subtraction angiography, CT, MRI, and transcranial color Doppler examination. Digital subtraction angiography is used as the gold standard. However, it is a costly and time-consuming invasive diagnosis that requires some radiation exposure, and is poorly accepted by patients. As such, it is mostly adopted in interventional therapy in the clinic. CT is now accepted as a rapid, simple, and reliable non-invasive method for use in diagnosis of cerebrovascular disease and preoperative appraisal. Ultrasonic Doppler can be used to reflect the hardness of the vascular wall and the nature of the plaque more clearly than CT and MRI. CONCLUSION： At present, there is no unified standard of classification of cerebral infarction imaging. Detection of clinical super-acute cerebral infarction remains controversial due to its changes on imaging, lack of specificity, and its similarity to a space-occupying lesion. Neuroimaging diagnosis for cerebral infarction remains a highly active area of research and development.展开更多
OBJECTIVE: To evaluate the value of perfusion MR imaging and angiographic evidence of collateral circulation in symptomatic patients with ischemic cerebrovascular diseases (ICVD). METHODS: Cerebral angiography and per...OBJECTIVE: To evaluate the value of perfusion MR imaging and angiographic evidence of collateral circulation in symptomatic patients with ischemic cerebrovascular diseases (ICVD). METHODS: Cerebral angiography and perfusion MR were performed in 16 patients with symptoms of ICVD. Qualitative perfusion maps were calculated for regional cerebral blood volume (rCBV) and mean transit time (MTT). RESULTS: A total of 27 lesions were seen on the perfusion MR maps (6 infarcts and 21 ischemic lesions) and most of them (26/27) showed a prolonged MTT. MTT is sensitive to the presence of ischemic lesions, but not sufficient in distinguishing infarct from ischemia. All of the infarcts showed a decreased rCBV, while most of the ischemic lesions showed a normal or increased rCBV. When collateral circulation was identified on angiography, most ischemic lesions were not infarcts and had a normal or increased rCBV. The absence of angiographically identifiable cerebral collaterals may not always result in an infarct; 50% had decreased rCBV. Despite the absence of angiographic collaterals, the other half had normal or increased rCBV. CONCLUSION: Cerebral angiographic evidence of collateral circulation is important in identifying a favorable outcome in patients with ICVD. However, a lesion with a normal or increased rCBV suggests a sufficient collateral circulation even without angiographic collaterals. Perfusion images may be a potentially useful adjunctive tool in the prediction of the outcome of ICVD, particularly where no apparent collateral macrocirculation is seen on CA.展开更多
基金supported by the Science and Technology Plan Project of Dalian City in China,No.2014E14SF186
文摘Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI.
文摘OBJECTIVE： To identify global research trends in neuroimaging diagnosis for cerebral infarction using a bibliometric analysis of the Web of Science. DATA RETRIEVAL： We performed a bibliometric analysis of data retrieval for neuroimaging diagnosis for cerebral infarction containing the key words ＂CT, magnetic resonance imaging, MRI, transcranial Doppler, transvaginal color Doppler, digital subtraction angiography, and cerebral infarction＂ using the Web of Science. SELECTION CRITERIA： Inclusion criteria were： （a） peer-reviewed articles on neuroimaging diagnosis for cerebral infarction which were published and indexed in the Web of Science; （b） original research articles and reviews; and （c） publication between 2004-2011. Exclusion criteria were： （a） articles that required manual searching or telephone access; and （b） corrected papers or book chapters. MAIN OUTCOME MEASURES： （1）Annual publication output; （2） distribution according to country; （3） distribution according to institution; （4） top cited publications; （5） distribution according to journals; and （6） comparison of study results on neuroimaging diagnosis for cerebral infarction. RESULTS： Imaging has become the predominant method used in diagnosing cerebral infarction. The most frequently used clinical imaging methods were digital subtraction angiography, CT, MRI, and transcranial color Doppler examination. Digital subtraction angiography is used as the gold standard. However, it is a costly and time-consuming invasive diagnosis that requires some radiation exposure, and is poorly accepted by patients. As such, it is mostly adopted in interventional therapy in the clinic. CT is now accepted as a rapid, simple, and reliable non-invasive method for use in diagnosis of cerebrovascular disease and preoperative appraisal. Ultrasonic Doppler can be used to reflect the hardness of the vascular wall and the nature of the plaque more clearly than CT and MRI. CONCLUSION： At present, there is no unified standard of classification of cerebral infarction imaging. Detection of clinical super-acute cerebral infarction remains controversial due to its changes on imaging, lack of specificity, and its similarity to a space-occupying lesion. Neuroimaging diagnosis for cerebral infarction remains a highly active area of research and development.
文摘OBJECTIVE: To evaluate the value of perfusion MR imaging and angiographic evidence of collateral circulation in symptomatic patients with ischemic cerebrovascular diseases (ICVD). METHODS: Cerebral angiography and perfusion MR were performed in 16 patients with symptoms of ICVD. Qualitative perfusion maps were calculated for regional cerebral blood volume (rCBV) and mean transit time (MTT). RESULTS: A total of 27 lesions were seen on the perfusion MR maps (6 infarcts and 21 ischemic lesions) and most of them (26/27) showed a prolonged MTT. MTT is sensitive to the presence of ischemic lesions, but not sufficient in distinguishing infarct from ischemia. All of the infarcts showed a decreased rCBV, while most of the ischemic lesions showed a normal or increased rCBV. When collateral circulation was identified on angiography, most ischemic lesions were not infarcts and had a normal or increased rCBV. The absence of angiographically identifiable cerebral collaterals may not always result in an infarct; 50% had decreased rCBV. Despite the absence of angiographic collaterals, the other half had normal or increased rCBV. CONCLUSION: Cerebral angiographic evidence of collateral circulation is important in identifying a favorable outcome in patients with ICVD. However, a lesion with a normal or increased rCBV suggests a sufficient collateral circulation even without angiographic collaterals. Perfusion images may be a potentially useful adjunctive tool in the prediction of the outcome of ICVD, particularly where no apparent collateral macrocirculation is seen on CA.
