Objective To investigate the role of peffusion-weighted magnetic resonance imaging （MRI） in evaluation of cirrhotic fiver. Methods With a 4F catheter, 1% diluted carbon tetrachloride （ 1 ml/kg） was selectively in...Objective To investigate the role of peffusion-weighted magnetic resonance imaging （MRI） in evaluation of cirrhotic fiver. Methods With a 4F catheter, 1% diluted carbon tetrachloride （ 1 ml/kg） was selectively injected into fight or left hepatic artery of 12 dogs fortnightly. The half fiver into which carbon tetrachloride was injected was called as study side （SS）, while the other half fiver without carbon tetrachloride injection was called as study control side （SCS）. Conventional and peffusion-weighted MRI were performed in every 4 weeks. Via a 4F catheter, 5ml gadolinium diethylentriamine pentaaceti acid （Gd-DTPA） dilution was injected into superior mesenteric artery at the 5th scan. The signal intensity-thne curves of SS, SCS, and portal vein were completed in MR workstation. The maximal relative signal increase （ MRSI）, peak time （ tp）, and slope of the curves were measured. Results On conventional MR images, no abnormalities of externality and signal intensity were observed in both SS and SCS of fiver at each stage. The mean tp, MP, SI, and slope of intensity-time curves in normal fiver were 10. 56 seconds, 1.01, and 10. 23 arbitrary unit （au）/s, respectively. Three parameters of curves didn＇t show obvious change in SCS of fiver at every stage. Abnormal perfusion curves occurred in SS of fiver at the 12th week after the 1st injection. The abnormality of perfusion curve in SS was more and more serious as the times of injection increased. The mean tp, IVlRSI, and slope intensity-time curves in SS of fiver were 19.45 seconds, 0. 43, and 3. 60 au/s respectively at the 24th week. Conclusion Perfusion-weighted imaging can potentially provide information about portal peffusion of hepatic parenchyma, and to some degree, reflect the severity of cirrhosis.展开更多
Objective To investigate the difference in interictal perfusion patterns between refractory and non-refractory temporal lobe epilepsies evaluated with flow-sensitive alternating inversion recovery (FAIR) magnetic reso...Objective To investigate the difference in interictal perfusion patterns between refractory and non-refractory temporal lobe epilepsies evaluated with flow-sensitive alternating inversion recovery (FAIR) magnetic resonance (MR) sequence. Methods Nine patients with refractory temporal lobe epilepsy, 21 patients with non-refractory temporal lobe epilepsy, and 13 normal volunteers underwent FAIR MR scanning. The relative cerebral blood flow (rCBF) in bilateral hemispheres and mesial temporal lobes were measured. And we also calculated the asymmetry index (AI) values. Results The AI values of bilateral hemispheres in refractory and non-refractory epilepsy patients were both significantly different from those of volunteers (P=0.012 and 0.029, respectively). There was significant difference in AI values of bilateral mesial temporal lobes between non-refractory epilepsy patients and volunteers (P=0.049), while no significant difference between refractory epilepsy patients and volunteers. Conclusions The hypoperfusion pattern of interictal refractory temporal lobe epilepsy patients is different from that of non-refractory patients. Although the hypoperfusion tends to extend out of temporal lobes in all patients, the refractory epilepsy patients have a preference of bilateral mesial temporal hypoperfusion, which may be valuable for evaluating prognosis.展开更多
文摘Objective To investigate the role of peffusion-weighted magnetic resonance imaging （MRI） in evaluation of cirrhotic fiver. Methods With a 4F catheter, 1% diluted carbon tetrachloride （ 1 ml/kg） was selectively injected into fight or left hepatic artery of 12 dogs fortnightly. The half fiver into which carbon tetrachloride was injected was called as study side （SS）, while the other half fiver without carbon tetrachloride injection was called as study control side （SCS）. Conventional and peffusion-weighted MRI were performed in every 4 weeks. Via a 4F catheter, 5ml gadolinium diethylentriamine pentaaceti acid （Gd-DTPA） dilution was injected into superior mesenteric artery at the 5th scan. The signal intensity-thne curves of SS, SCS, and portal vein were completed in MR workstation. The maximal relative signal increase （ MRSI）, peak time （ tp）, and slope of the curves were measured. Results On conventional MR images, no abnormalities of externality and signal intensity were observed in both SS and SCS of fiver at each stage. The mean tp, MP, SI, and slope of intensity-time curves in normal fiver were 10. 56 seconds, 1.01, and 10. 23 arbitrary unit （au）/s, respectively. Three parameters of curves didn＇t show obvious change in SCS of fiver at every stage. Abnormal perfusion curves occurred in SS of fiver at the 12th week after the 1st injection. The abnormality of perfusion curve in SS was more and more serious as the times of injection increased. The mean tp, IVlRSI, and slope intensity-time curves in SS of fiver were 19.45 seconds, 0. 43, and 3. 60 au/s respectively at the 24th week. Conclusion Perfusion-weighted imaging can potentially provide information about portal peffusion of hepatic parenchyma, and to some degree, reflect the severity of cirrhosis.
文摘Objective To investigate the difference in interictal perfusion patterns between refractory and non-refractory temporal lobe epilepsies evaluated with flow-sensitive alternating inversion recovery (FAIR) magnetic resonance (MR) sequence. Methods Nine patients with refractory temporal lobe epilepsy, 21 patients with non-refractory temporal lobe epilepsy, and 13 normal volunteers underwent FAIR MR scanning. The relative cerebral blood flow (rCBF) in bilateral hemispheres and mesial temporal lobes were measured. And we also calculated the asymmetry index (AI) values. Results The AI values of bilateral hemispheres in refractory and non-refractory epilepsy patients were both significantly different from those of volunteers (P=0.012 and 0.029, respectively). There was significant difference in AI values of bilateral mesial temporal lobes between non-refractory epilepsy patients and volunteers (P=0.049), while no significant difference between refractory epilepsy patients and volunteers. Conclusions The hypoperfusion pattern of interictal refractory temporal lobe epilepsy patients is different from that of non-refractory patients. Although the hypoperfusion tends to extend out of temporal lobes in all patients, the refractory epilepsy patients have a preference of bilateral mesial temporal hypoperfusion, which may be valuable for evaluating prognosis.
