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Objective To investigate the feasibility of automatic spectral imaging protocol selection (ASIS) and adaptive statiatical iterative reconstruction (ASiR) technique to reduce radiation dose and dose of contrast agent.Methods Sixtyfour patients underwent routine abdominal examination were randomly divided into two groups.The test group used ASIS technique,with 30％ ASiR and 50％ ASiR reconstruction algorithm.The control group used 120 kVp tube voltage,FBP reconstruction method.The noise of liver,pancreas,sacrospinal muscle,CNR of liver and pancreas,subjective image score in arterial phase and portal venous phase were compared between the image of 70 keV+30％ ASIR and control group.CNR of abdominal aorta and its branchs,CNR of portal vein,and subjective image score were statistically analyzed between im age 55 keV+50％ ASiR and control group in the arterial phase and portal venous phase.Results Compared with control group,CT dose index volume for arterial phase and portal venous phase in test group decreased by 23.68％,23.57％ and dose length product decreased by 25.61％,18.45 ％,total contrast injection decreased 16.86 ％,the noise of liver,pancreas and sacrospinal muscle in 70 keV+30％ ASiR were lower than those of control group in abdominal arterial and portal phase (all P＜0.05).CNR of abdominal aorta,superior mesenteric artery,celiac axis and score in 55 keV+50％ ASiR were higher than those of control group in abdominal arterial phase (all P＜0.05),CNR of portal vein and score in portal phase had no statistically difference (all P＞ 0.05).Conclusion Combining of ASIS and ASiR including 70 keV + 30％ ASiR and 55 keV+50％ ASiR,images are superior to that of the conventional 120 kVp+FBP scan mode for abdominal CT image and vessel image quality,which can reduce the radiation dose and the dose of contrast agent.
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Objective To investigate the hemodynamics of basilar artery and its blood-supply area in patients with vertigo by 3.0 T MR.Methods Fifty patients with vertigo were selected as case group and 50 healthy volunteers were selected as control group.All subjects in the case group and in control group were examined by brain magnetic resonance imaging (MRI),magnetic resonance angiography(MRA),fast cine phase contrast(Fast CINE PC) and flow-sensitive alternating inversion recovery sequence (FAIR).After image postprocessing,the velocity and the blood flow volume of basilar artery were measured and calculated.The FAIR value of bilateral occipital lobe,cerebellum,pons and medulla oblongata was measured.Statistical testing was performed.Results The average velocity,peak velocity and blood flow volume of the basilar artery in case group were significantly lower than those in the control group(the average velocity:(22.47 ±9.14) cm/s vs (31.41 ±5.97) cm/s,t =-5.79,P ＜ 0.0001 ; peak velocity:(31.60 ± 13.18) cm/s vs (44.00 ± 7.84) cm/s,t =-5.71,P ＜0.0001 ;blood flow volume:(91.14 ±43.92) ml/min vs (127.49 ± 28.33) ml/min,t =-4.92,P ＜0.0001).The perfusion of the posterior circulation in the case group was lower than that in the control group ((882.35 ±35.22) vs (906.34 ±36.82),t =-3.33,P =0.0012).The average velocity,peak velocity and blood flow volume of the basilar artery in case group whose brain parenchyma and blood vessels were normal were (26.31 ±5.16) cm/s,(36.33 ±6.60) cm/s,(95.38 ±28.16) ml/min respectively,which were all less than those in the control group (average velocity:t =-2.72,P =0.0086 ; peak velocity:t =-3.12,P =0.0027 ;blood flow volume:t =-3.53,P =0.0008).The perfusion of the basilar artery blood-supply area in case group whose brain parenchyma and blood vessels were normal was (904.00 ± 35.82),there was no difference when compared with the control group (906.00 ± 36.82,t =-0.20,P =0.8427).Conclusion Whether the brain parenchyma and blood vessels is normal or not,the velocity and blood flow volume of the basilar artery in patients with vertigo are decreased,but the perfusion of the basilar artery blood-supply area are different,it depends on whether there is ischemia.
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Objective To evaluate the diagnostic value of physical examination,digital mammography and color Dopplor ultrasonography for breast masses.Methods The materials of clinic,digital mammography and color Dopplor ultrasonogrpahy(US)in 92 women(raged from 18～80 years old in age,with average of 49.8 years old)with breast masses confirmed by pathology were retrospectively analysed,including benign in 43 and malignant in 49.Digital mammographic findings including the location,shape,margins,calcifications and the lymph node of axillary of the breast lesions,and color Dopplor ultrasonographic findings including mainly the characteristics of lesions on two-dimensional sonography,the distribution of the internal and peripheral vessels of the lesions were observed,the physical examination mainly observed the skin and nipple,and the margins,texture and movement of the lesions.Results In diagnosing breast masses,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy were 85.71%,79.07%,82.35%,82.93% and 82.61%,respectively with digital mammography,79.59%,83,72%,84.78%,78.26% and 81.52%,respectively with US,71.42%,76.74%,77.78%,70.21%,73.91%,respectively with physical examination,while were 91.84%,93.02%,93.75%,93.3% and 90.91%,respectively in combination with three methods,which were significantly higher than that of each single examination(P＜0.05),but there were no differences between each examination(P＞0.05).Conclusion It can improve the diagnosing accuracy of breast masses by suitable combination of three of digital mammography,color Dopplor ultrasonography and physical examination.
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Objective To evaluate the changes of cerebral perfusion and hemodynamics in the patients with mono-carotid artery stenosis after stenting with the technique of DSA parametric imaging. Methods 15 patients with mono-carotid artery stenosis(the stenosis>75%) undergone carotid stenting were choosed. Digital subtraction imagines of diplo-carotid arteries were acquired before and after operation, then the imagines were processed by special soft ware in personal computer. The region of interest (ROI)were selected in the brain,internal carotid artery and superior sagittal sinus separately, the time-gray scale curves of the ROIs were drawn with the soft ware, from which,then acquired the following parameters from the time-gray scale curves,the largest gray values of brain in disordered side pre-and post-operation, and the parameters including peak value (PV), mean transit time (MTT) ,time to peak (TP), time of appearance to the peak , the max slope rate of the curve and relative time of cerebral circulation were also evalua-ted, respectively. The imaging speed was 7.5 pictures per second. The results were statistically evaluated by using matched-t test. Results Before the stenting, the values of the parameters peak value, the max slope rate of the curve,TP,MTT,relative time of cer-ebral circulation were 108.20±5.58 , 1.23±0.37 , (4.78±0.24)s , (8.20±0.42)s and(4.92±1.03)s , respectively; after the stenting , the values of the parameters above-mentioned were 114.20±7.58, 2.01±0.36, (4.14±0.40)s, (3.55±0.56)sand(4.18±0.89) s , respectively, the difference of the parame-ters above-mentioned pre-and post-operation were statisti-cally significant (t=5.97 , 8.00 , 0.21 , 10.21 , 10.12 and 4.14,P<0.05). Before and after operation, the values of time of appearance to the peak were (5.39±0.24) s and)(5.37±0.78) s , respectively , there was no statistical significance (t=0.21, P> 0.05). Conclusion DSA parametric imaging can be used to evaluate the changes of cerebral perfusion and hemodynamics before and after arterial stenting.
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MR-T1ρ imaging is one of the novelest MRI techniques in recent years,T1ρ relaxation mainly reflect the interaction between water molecules and the surrounding macromolecu]es.Due to the unique point of view,the technique has been used to investigate a variety of pathological mechanisms in early stage of diseases,such as the content of collagen protein in articular cartilage,neuron apoptosis in neurodegenerative diseases and so on,which provides a new tool for detecting lesions in ultra-early stage or the evaluation of treatment effect.
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Objective To assess the value of a fibrin-targeted contrast agent (EP-2104R) for MR detection of thrombus, and to compare this modality with non-contrast-enhanced (NCE) MRI and Gd-DTPA injection at acute period after thrombus generation. Methods Thrombus was induced with external injury and stasis in 5 rabbits. MRI was performed before and after contrast agent injection at 6.0 h after injury, and the MRI findings were compared with that of histopathologically examinations. Results EP-2104R enhanced MRI accurately detected thrombus, which was superior to both NCE and Gd-DTPA injection (P<0.001). Gd-DTPA injection was not associated with improvement of thrombus detection. Conclusion Being a fibrin-targeted MR contrast agent for in vivo detection of acute thrombus, EP-2104R is superior to NCE MRI and Gd-DTPA injection.
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Objective To explore the dynamic changes of diffusion tensor imaging(DTI) in spinal cord of goats with persistent compression injury. Methods Eighteen goats weighted 20--25 kg were divided into three groups with completely random design: A, B and C. A balloon catheter was inserted into the epidural space at C3-4 level via intervertabral foramen for each goat. The balloon was inflated by injection of variable volumes of saline in group A and B 10 days following operation. The volume of saline was 0. 3 ml in group A and 0. 2 ml in group B,respectively. The compression sustained for 40 days. Group C served as uncompressed control without injection of saline. The locomotor rating score was applied to each group. Conventional MRI and DTI were performed. The apparent diffusion coefficient (ADC)and fractional anisotropy (FA) values were measured. Histopathological assessments of the compressed spinal cord were performed 50 days following operation with light microscope and transmission electron microscopy. Results Before operation, the locomotor rating score was 5, the ADC value was ( 1.23 ± 0. 05 ) × 10-3 mm2/s and the FA value was (0. 72 ± 0. 05 ) each group. Of six goats in Group A, the locomotor rating score severely decreased and reached( 1.5±0. 4)on the 40 th day after compression. The ADC value at compression site decreased soon and reached the minimum (0. 75±0. 04) × 10-3mm2/s on the 5 th day after compression. Then the ADC value increased gradually, restored normal on the 10 th day or so, then became markedly higher than normal and reached( 1.61±0. 05) × 10-3mm2/s on the 40 th day. The FA value at compression site decreased soon, reached(0. 54±0. 04)on the 1st day, then decreased gradually and reached(0. 43 ± 0.05) on the 40 th day. It appeared high signal intensity on T2WI on the 10 th day. In Group B, the locomotor rating score was moderately decreased and reached(3.4±0. 5 )on the 40 th day. The ADC value at compression site decreased slightly firstly, reached( 1.08±0. 04) × 10-3mm2/s on the 1st day, restored normal on the 20 th day or so, then increased gradually, became higher than normal and reached ( 1.27 ± 0. 05) × 10-3mm2/s on the 40 th day. The FA value increased slightly firstly, reached (0. 78±0. 05 )on the 1st day, then decreased gradually, restored normal on the 15 th day or so, became lower than normal and reached(0. 67±0. 05) on the 40 th day. There was no abnormality on conventional MRI. In Group C, the locomotor rating score, ADC value and FA value remained unchanged. There was no abnormality on conventional MRI. There were dynamic changes over time of the ADC value and FA value in Group A and B, which was more marked in Group A than that in Group B ( repeated measurements analysis of variance, F=426. 7 for the ADC value and F =7895.2 for the FA value, P < 0. 01 ). Histopathologically, swelling and degeneration of axons and neurons as well as the disarrangement of myelin sheathes could be seen. The pathological changes were more marked in Group A than in Group B. In Group C, no abnormality could be seen. Conclusion There are dynamic changes of DTI in cervical spinal cord with compressive injury that correlated with the degree and duration of compression. The ADC value decreased firstly, restored normal and then increased. The FA value increased firstly, restored normal and then decreased in mild compression while solely decreased in serious compression.
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Objective To observe the diffusion characteristics and pathology changes with DTI in rabbit models with mild cerebral contusion and laceration (CCL). Methods Thirty rabbits were randomly selected and made into models of mild CCL by free fall, while other 10 rabbits were cut only in the skull as control. T2WI and DTI were performed 1, 3, 6, 12, 24, 48 and 72 h after the operation. DTI value of average diffusion coefficient (DCavg) and fractional anisotropy (FA) of mild CCL and its peripheral area were measured and compared. Histological examination was also performed. Results One hour after operation, CCL area showed high signal on T2WI, and no abnormal signal was found in the peripheral area, but both had abnormal color on DTI map. T2WI signal intensity in peripheral area of 22 rabbits (73.33%) increased gradually and had much abnormal color on T2WT map after 3 h. There was significant difference of FA and DCavg between CCL and the mirror region, the peripheral area and the mirror region (P<0.05). The value of FA decreased slightly since 12 h. More prominent tissue necrosis, edema and hemorrhage were found in CCL area than in the peripheral area with pathology examination. No abnormal manifestations of the brain were detected with both pathology and MR examination in the control rabbits. Conclusion DTI is sensitive for detecting mild CCL and can show it directly on color map, and thus may be used as a routine examination in the evaluation of mild CCL.
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The research of hemorrhagic transformation (HT) after cerebral infarction is now focus on HT after thrombolytic therapy. However, attention should also be aroused to the occurrence of spontaneous HT in most patients who cannot receive thrombolysis promptly because of various reasons, for it has important influence on the treatment of cerebral infarction and prognosis. This article reviews the concept, typing, pathogenesis, correlation factors, imaging diagnosis and prediction of HT, as well as the effects of non-thrombolytic therapies on HT, such as antiplatelet, defibrase, anticoagulant, anti-free radical, and the relations between HT typing and prognosis.
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To observe the morphology and anatomic variations of the circle of Willis and its clinical significance. To measure and establish the normal reference parameters of average diameters of its component vessels in the healthy Chinese by using 3D-TOF MR angiograms and to determine whether age-or sex-related differences exists in the circle' anatomy. MRA was performed in 153 healthy subjects. According to its integrity, Willis'circle was divided into four types: (1) Type I, showing an intact circle. (2) Type II, having a complete anterior circulation but an incomplete posterior circulation. (3) Type III, having an incomplete anterior circulation but a complete posterior circulation. (4) Type IV, having an incomplete anterior and posterior circulation. Based on the development of the components of the circle, each type was subdivided into four subtypes: typical, variable, hypoplastic and mixed. The statistically significant differences were not found in each type or subtypes between the different age and sex groups. Result of 153 cases, Type I, II, III and IV was found in 53 (34.64%), 73 (47.71%), 8 (5.23%), and 19 (12.42%) respectively. The display rate of the anterior and the posterior communicating arteries was 87.58%o (134/153) and 65.34% (100/153) respectively. Display rate of fetaltype posterior cerebral artery(PCA) was 20.92%. 3D-TOF MR angiography has important clinical significance for evaluating morphology and anatomic variations of circle of Willis. The normal values of diameter of cerebral arteries on MR angiograms may play a reference role in diagnosing cerebral vascular diseases.
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Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Anthropometry , Circle of Willis , Diagnostic Imaging , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Methods , RadiographyABSTRACT
Objective To observe the effect of NGF on the caspase-12 in cerebral ischemia/reperfusion. MethodsTwenty-six healthy male white rabbits were randomly divided into sham, ischemia/reperfusion and NGF group. The tissues were sampled to detect the expression of caspase-12, caspase-3 by immunohistochemistry, and to detect the cerebral apoptosis by flow cytometry and TUNEL staining methods.Results Compared with sham group, the expression of caspase-12 and caspase-3 in I/R group was higher (P
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BACKGROUND:It has been found that central nervous system is involved in Guillain-Barre syndrome and Miller-Fisher syndrome, and the involved sites include optic nerve, brain stem and cerebellum. Abnormal signal of MRI can be observed in the brainstem and spinocerebellar tract of patients with Miller-Fisher syndrome. To establish an animal model of encephalitis after infection of Campylobacter jejuni, and investigate the mechanism of formation by means of imaging, immunology and pathology.OBJECTIVE: To construct an animal model of lesion of central nervous system after infection of Campylobacter jejuni Penner 4.DESIGN: A randomized grouping designed, controlled animal experiment.SETTING: Department of Imaging and Department of Neurology, Second Hospital of Hebei Medical University.MATERIALS: The experiment was carried out in the Laboratory of Molecular Imaging, the Second Hospital of Hebei Medical University between August and December 2003. Fifteen healthy flap-eared rabbits were randomly divided into experimental group (n=10) and control group (n=5).METHODS: In the experimental group, Campylobacter jejuni inactivated bacteria liquor was completely emulsified with complete Freund adjuvant (CFA) of the same volume in week 1, and then the rabbits were immunized with subcutaneous injection at multiple points of bilateral axilla, bilateral groins and side of back spine, 1 mL for each site, and 5 mL for each rabbit; The rabbits were further immunized with intraperitoneal injection of simple Campylobacterjejuni inactivated bacteria liquor in the following every two weeks, 5 mL for each time in each rabbit for 5 times. In the control group, the Campylobacter jejuni inactivated bacteria liquor was replaced by saline of the same volume, the injected method and time were all the same as those in the experimental group. Evaluative methods: ①Symptoms and physical signs: their mental status, conditions of diet, urine and excrement, and activities of limbs were observed; ② Serological examination: the contents of anti-Campylobacterjejuni antibody, anti-IgG GM1 antibody and myelin basic protein (MBP) were detected with enzyme-linked immunoadsorbent assay (ELISA); ③ MRI examination was applied to the randomly selected rabbits before every immunization with Toshiba 1.5 T MRI instrument. The scanning sequence included spin-echo T1-weighted image with the scanning parameter of 500/15 ms (TR/TE); rapid spin-echo T2-weighted image, 4 000/108 ms (TR/TE); fluid attented inversion recovery (Flair) sequence, the parameter was 10 000/120 ms (TR/TE), inversion angle was 90°. The thickness of scanning layer was 4.0 mm, and the layer space was 0.8 mm. ④ Histological examination: At 4 weeks after the first immunization, the attacked animals were induced to death by cardiac perfusion, and the skull was opened immediately to remove optic nerve, part white matter, hippocampus, brainstem, cerebellum and spinal cords of neck, chest and waist, which were fixed with formaldehyde solution (40 g/L),and hematoxylin-eosin (HE) staining, fast blue staining and MBP immunohistochemical staining were performed respectively. At 10 weeks after immunization, 5 randomly selected rabbits in the experimental group and the 5 rabbits in the control group were treated with the same methods to obtain the histological samples.MAIN OUTCOME MEASURES: The symptoms and physical signs,contents of anti-Campylobacterjejuni antibody, anti-IgG GM1 antibody and MBP, imaging observation and histological examination were mainly observed.RESULTS: Fifteen animals were enrolled, 14 were involved in the analysis of results, 1 rabbit in the experimental group died at 4 weeks after immunization. ① Mental symptoms and disorder of limb's activity occurred in 1 rabbit in the experimental group at 2 weeks after immunization. ② In the experimental group, titre of anti-Campylobacterjejuni-IgG antibody in serum reach the peak at 2-4 weeks. From week 2, the serum A value was significantly higher in the experimental group than in the control group (1.923±0.403, 0.973±0.633, P ＜ 0.05). The IgG type GM1 (A value) was obviously elevated at week 8, but insignificantly different from that in the control group (0.115±0.042, 0.097±0.039, P ＞ 0.05). The MBP content (Avalue) in serum was significantly elevated at the 8th week (0.134±0.041).③ The imaging examination showed that abnormal MRI signal of different degree occurred at 2-4 weeks after immunization in the experimental group. ④ The histological changes showed that there was swelling of myelin sheath at the sites of brainstem, medulla oblongata, cervical spinal cord, thoracic spinal cord and lumbar spinal cord in the experimental group, no inflammatory cell infiltration and deletion of myelin sheath were observed. No obvious changes at the above site were observed in the contro1 group.CONCLUSION: Campylobacterjejuni Penner 4 can induce lesion of central nervous system.
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BACKGROUND: Vascular endothelium growth factor (VEGF) is an endothelium mitogen and angiogenic factor with strong potential during recovery from cerebral infarction (CI). Can such therapeutic effect be detected with magnetic resonance diffusion imaging?OBJECTIVE: To study the therapeutic efficacy of VEGF plasmid in treating focal cerebral infarction in a dog experimental model with the aid of diffusion- and hemodynamic-weighted magnetic resonance imaging (MRI),with the morphological results compared with those of immunohistochemical examination.DESIGN: Completely randomized controlled, double blind evaluation,analysis of variance, Pearson correlation analysis, follow-up for 2 weeks.SETTING: Department of Medical Iconography, the Second Affiliated Hospital of Hebei Medical University.MATERIALS: This study was carried out at the Department of Medical Iconography, the Second Affiliated Hospital of Hebei Medical University,between April 2001 and March 2002. Totally 18 healthy adult dogs weighing 10-15 kg were randomly divided into control group and experiment group with half in each.METHODS: All dogs were subjected to femoral intubation and then made into CI model by the occlusion of middle cerebral artery with an embolus injected through the internal carotid artery. Dogs in control group were put to death at postoperative 24 hours, 1 week and 2 weeks with three at each time point, while four dogs in experiment group were put to death at postoperative 1 week and five at 2 weeks. Dogs in experiment group received microinjection of 0.5 mL fluid containing pcD2/hVEGF121 (500-600 μg)instantly after operation, which was replaced with physical saline of the same volume at the same time point in control group. Then they were subjected to MRI scanning once an hour for 4 times, with the sequence of T1WI, T2WI, 3D-TOFMRA, DWI and CET1WI, which was repeated at postoperative 24 hours, 3 days, 1 week and 2 weeks. Based on the MR images, pathological focuses were selected for morphological observation of cells with the aid of HE staining, and CD34 IHC staining was used for counting micrangium, as well as VEGF staining for VEGF positive cells.Then the apparent distribution coefficient (ADC) was calculated, and the differences between different time points and groups were analyzed by analysis of variance. The number of capillaries and VEGF positive cells of each high-power field was counted, with the results compared with those of MR scanning so as to explore the correlation between MR signal changes and IHC results.MAIN OUTCOME MEASURES: ① The number of capillaries and VEGF positive cells in each high-power field was counted at postoperative 24 hours, 1 week and 2 weeks; ② MR images of each group.RESULTS: Data of the 18 dogs entered the final analysis. ① Diffusionweighted imaging (DWI) showed higher signals at infarctional region at postoperative 1 hour, which became strengthened as time went by. ②ADC decreased to (5.61 ±1.39) mm2/s at postoperative 3-4 hours, about 43% lower than that of the opposite hemisphere [(9.85±2.04) mm2/s]. It resumed to (9.83±1.11) mm2/s, but was still lower than the normal level.③ The subsequent MR scanning proved that ADC ratio presented an increasing tendency in contrast with the decreasing tendency at super-acute stage. The increment was even more marked in control group and the difference was significant at postoperative 2 weeks (P=0.032, 0.006). ④ The number of capillary positive cells on the affected side in experiment group was significantly higher than that in control group at postoperative 2 weeks [(28.80±3.29)/field, (20.70±4.47)/field, (P ＜ 0.01)]. ⑤ The number of VEGF positive cells on the affected side in experiment group was significantly higher than that in control group at postoperative 1 and 2weeks [(64.20±9.40)/field, (51.90±5.74)/filed; (72.70±6.98)/filed,(58.40±6.35)/field, (P ＜ 0.01)].⑥ The results of MR scanning and IHC were subjected to correlation analysis and revealed that ADC ratio was closely correlated with the number of capillary positive cells, with Pearson correlation coefficient being 0.679 (P ＜ 0.01). Moreover, the number of capillaries and the number of VEGF positive cells were significantly correlated (r=0.668, P ＜ 0.01).CONCLUSION:Morphological observation and IHC revealed that both the local capillaries and VEGF protein content increased markedly in timedependant manner due to VEGF plasmid gene therapy.Meanwhile,the change of ADC ratio was found to be closely correlated with the number of VEGF positive cells and the number of capillaries.
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Objective To evaluate the clinical and MRI features of choroid metastatic tumors.Methods Clinical and MRI findings in 4 cases with choroid lung carcinoma metastasis based on pathological results were retrospectively analyzed.Results Lung metastatic carcinomas were the most common primary cancers metastasizing to the choroid all the 4 cases had a decrease of visual acuity rapidly.MRI showed diffuse or local thickness of bulbar wall,and revealed T 1 isointense and T 2 iso-or hyperintense signals.A mass extruding into the bulb was seen in 1 patient.Conclusion MRI of choroid metastatic carcinoma has characteristic manifestations,and MRI is an effective and useful technique for the diagnosis of this lesion.
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Objective To establish a stable model of intraluminal thread approach in making focal cerebral ischemia/reperfusion modelin rabbit.Methods Forty New Zealand white rabbits were randomly divided into three groups:A,B,and C.Angiography of ICA wasperformed in group A(n=5). Control group B(n=5) was sham-operated.In group C(n=30),the focal cerebral ischemia/reperfusionmodel was made by inserting a wire ( d=0.45 mm ) into MCA through ICA and CCA directly and pulling it out 3 hours later . MRI andneurological deficit score were used to evaluate the effectiveness of models.Results Angiography could show the course and bifurcation of ICA clearly.22 models were successful.The pathological changes were shown on MRI.The neurological deficit score (reperfusion 1 h) were 2.8?0.45.Conclusion The focal cerebral ischemia/reperfusion model made by inserting a wire(d=0.45 mm) into MCA through ICA and CCA directly and pulling it out 3 hours later was stable and fit for imaging research.
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Objective To study the effects of basic fibroblast growth factor (bFGF) and Gingkgo biloba extra(GbE) on experimental cerebral infarction. Methods 40 healthy adult cats were equally devided into group A with sodiumchloride, group B with bFGF, group C with GbE and group D with bFGF+GbE in random.All animals were operated to establish the feline models of cerebral focal ischemia-reperfusion by the approach of left transorbital. The certain madicine intervene were take at 0 h,24 h,48 h after the models established.The neurological defects score was evaluated by Philips' criteria score in 1 d and 7 d. The physiological changes were observed by HE stained and electron microscope.Results The neurological defects score was singificiant lower in D group(41.50?8.18) than that in group A(82.20?8.08),B(63.60?6.22) and C (61.00?6.58)(allP
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Objective To evaluate the utility of diffusion-weighted MRI(DWI)and the correlation between the abnormalities in DWI and the clinical factors in patients with transient ischemic attack of the brain(TIA).Method Clinical,conventional MRI,and DWI data were collected on 59 consecutive patients with TIA between March and July 2006 within 7 days of the onset of TIA symptoms.The relationship between DWI-detected findings and patients' clinical manifestations was then analyzed.Results DWI-detected abnormalities were displayed in 22 of 59 cases(37%,positive group).Prolonged TIA duration(TIA duration≥30 minutes),repeated episodes,motor deficits,aphasia,history of either stroke or TIA,diabetes mellitus,and atrial fibrillation were observed more frequently in the positive group than in the negative group.In 9 of 22 cases,the identified lesions were not detected by conventional MRI(T2-weighted imaging or fluid-attenuated inversion recovery).In other 13 cases,abnormalities were present on both DWI and conventional MRI.Conclusions In TIA patients,prolonged TIA duration(TIA duration≥30 minutes),repeated episodes,motor deficits,aphasia,history of either stroke or TIA,diabetes mellitus,and atrial fibrillation were significantly correlated with detectable abnormalities on DWI.