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Objective T o study the correlation of daily living activities with location and severity of trau-m atic brain injury (TBI) and to provide a theoretical basis for im proving the accuracy of expert opinion. Methods Five hundred and one cases of patients with TBI were selected. D etailed records included fol-lowing: pre-injury situation, location and severity of injury, treatm ent and education. D aily living activi-ties scale (B arthel index) was applied to test the subjects’daily living activities. T he relevance am ong location and severity of TBI and B arthel index was statistically analyzed. Results In m ild TBI group, there wasnosignificantdifferenceinBarthelindex among each location (P>0.05).Inmoderate TBIgroup, there were significant differences in B arthel index between subarachnoid hem orrhage and cerebral lobe injury, also between parietal, occipital lobes injury and frontal lobe injury, parietal, occipital lobes injury and temporallobe(P0.05).In severe TBI,there were significant differences in Barthel index between every two different locations (P<0.05). Conclusion T here is som e correlation between the location of TBI and B arthel index, which provides an im portant reference value for analyzing and deter-m ining daily living activities after TBI.
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Objective To quantitatively evaluate the influence of fluid attenuated inversion prepared recovery (FLAIR) on apparent diffusion coefficient (ADC) and its clinical application value. Methods The data of DWI and FLAIR-DWI of 139 stroke were retrospectively reviewed. Paired t-test was used to analyze DWI (ADCCON ) and FLAIR-DWI (ADCFLAIR) values at varying time points from hyperacute to chronic stage. All of the lesions were further divided into cortex involved infarction and subcortical infarction. The ADCCON and ADCFLAIR values in the lesion sides and the contralateral sides were compared separately. Results The mean ADCCON values for lesions less than 6 hours, 7--12 hours, 13--24 hours, within 2 days, 3-4 days, 5-7 days and 8--14 days were not significantly different from those of the ADCFLAIR values(P >0.05) [ADCCON were (0.55±0.07), (0.50±0.09), (0.50±0. 13), (0.50 ± 0. 13), (0.62 ± 0. 14), ( 0. 60 ± 0. 12), (0. 72 ± 0. 20) × 10-3 mm2/s; ADCFLAIR were ( 0. 53 ± 0. 09 ), (0.49±0.06),(0.49±0.10),(0.48±0.08),(0.58±0. 14), (0.60±0.09),(0.73±0.15) × 10-3 mm2/s]. Lesions of 15 to 30 days [ (0. 95±0. 21 ) × 10-3 mm2/s and ( 1.02±0. 27) × 10-3 mm2/s for ADCFLAIR and ADCCON ] and the chronic stage ( >31 days) [ ADCFLAIR and ADCCON were (1.10 ± 0. 30) × 10-3 mm2/s and (1.36±0. 41 ) × 10-3 mm2/s respectively], had a significantly lower ADCFLAIR than those of the ADCCON (P <0. 01 ). For patients with a symptom duration of less than 14 days, the mean ADCFLAIR values of the cortex involved and subcortical lesions were all not significantly different from the mean ADCCON (P > 0. 05 ) [ ADCCON were ( 0. 55 ± 0. 16 ), ( 0. 61 ± 0. 14 ) × 10-3 mm2/s ; ADCFLAIR were (0.53±0. 14), (0.60±0. 13) × 10-3 mm2/s]. For patients with a symptom duration of longer than 14 days, the mean ADCFLAIR values of the cortex involved and subeortical lesions were all significantly lower than those of the mean ADCCON values [ ( 1.16±0. 36) × 10-3 mm2/s vs. ( 1.35±0. 48) × 10-3 mm2/s for cortex involved lesions and (0. 97±0. 19) × 10-3 mm2/s vs. ( 1.15±0. 33) × 10-3 mm2/s for subcortical lesions ] (P < 0. 01 ). The ADC values of the normal contralateral sides were significantly decreased after the fluid inversion prepared pulse was conducted [ ADCFLAIR, ( 0. 76 ± 0. 05 ) × 10-3 mm2/s and ADCCON, (0. 82 ± 0. 11 ) × 10-3 mm2/s ] ( p < 0. 01 ). Conclusions The FLAIR significantly decrease the absolute ADC values of the ischemic lesions 14 days later after the stroke onset, which may be helpful in determining individual lesion age. Meanwhile, the application of FLAIR can have a more accurate relative ADC value by reducing the free fluid partial volume effect of the normal contralateral side, and hence enhance the ability of detecting the subtle ischemic pathophysiological changes.
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Objective To evaluate the value of dynamic susceptibility-contrast (DSC) MR perfusion imaging in differentiating benign and malignant meningiomas on the basis of differences in their vascularity in both tumor parenchyma and peritumoral region. Methods 33 patients with pre-operation meningiomas(25 benign and 8 malignant) underwent conventional and DSC MR perfusion imaging. Maximum relative cerebral blood volume (rCBV) and corresponding relative mean transit time (rMTT) values of the same part in both tumor parenchyma and peritumoral region were calculated (compared with contralateral normal white matter). The peritumoral region was defined as the area immediately adjacent (0.05) in parenchyma part and both were statistically significant (t test, ?
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Objective To evaluate the accuracy of MR diffusion weighted imaging (DWI) in the diagnosis of hyperacute cerebral infarction. Methods Twenty one patients with onset of strokelike symptoms underwent conventional MRI and DWI within 6 hours. Results DWI indicated cerebral infarction in 16 patients, all of whom had a final diagnosis of acute stroke. DWI was negative in 5 patients, all of whom had a final diagnosis of TIA. The abnormality seen at DWI was confirmed with follow up study. DWI had a sensitivity of 100% and a specificity of 100% in the diagnosis of hyperacute cerebral infarction, and conventional MRI interpretation yielded a sensitivity and specificity of 25% and 100%, respectively. Conclusion DWI is highly accurate in diagnosing hyperacute cerebral infarction and is superior to conventional MRI.
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Objective To determine the reliability of CT perfusion scans and its parameters of ?-variate curve in evaluating the acute myocardial infarction for clinical reference of diagnosis on coronary artery disease and myocardial infarction. Methods Imatron C-150 electron beam CT (EBCT) were used to scan a hydrodynamic model which could mimic a change of contrast medium by intravenous injection in vivo. Then 6 adult canines were employed in the experiment with thoracic operation, and branches of the anterior descending and circumflex of left coronary arteries (LCA) were ligated so that myocardial infarction was made out. After intravenous administration of contrast medium, the hearts were scanned with perfusion EBCT and ?-variate curves were manifested. Some heterogeneities and differentiations between the normality and the infarctions were put forward when the parameters of all these curves were analyzed and statistically processed. Two myocardial infarctions were also verified by SPECT, and all the samples stained with TTC method were compared with those on the perfusion images. The pathological study with optical microscope and electron microscope were further carried on. Results The ascending slopes of ?-variate curves were different in the perfusion quantity. The normal curve of canine myocardium showed a somewhat quick ascending pattern first, and then a gradual descending pattern successively, with the ascending time of about 10-13 s, ascending CT value of about 34-37 HU, and peak CT value of about 70-81 HU. Whereas the curve on myocardial infarction demonstrated a prolonged ascending time of about 19.9 s, diminished ascending CT value of only about 20 HU, and peak CT value of about 53.8 HU, which were significantly different from the normality (P
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Objective To study the imaging features and the cause of the cystic meningiomas so as to avoid the misdiagnosis and improve the understanding and knowledge. Methods CT and MRI features in 27 pathologically proved cystic meningiomas were analyzed. There were 10 men and 17 women, and the age ranged from 16 to 80 years with the average age of 49 years. Twenty-six patients were examined by using MRI (24 with enhanced scan), and 15 patients by CT (seven with enhanced scan). 15 patients were examined by both CT and MRI. The image features were analyzed according to Nauta and were compared with operative and pathological findings. Results The cystic meningiomas were mostly epithelial type, but fibrous type, angiomatous type, or papillary type may also be seen. Mostly, the locations were cerebral convexity, but tumors of the tentorium, alisphenoid, olfactory groove, and skull base were also seen. And all were sessile. On imaging, most tumors were parenchymatous with cystic parts, and marked enhancement of the parenchymatous part could be seen. Some were entirely cystic with parenchymatous nodule, the nodule enhanced markedly and the wall of the cyst may be or not be enhanced. Of the 27 cases, four cases were NautaⅠ, seven cases were NautaⅡ, one case was Nauta Ⅲ, and ten cases were Nauta Ⅳ. Three were both Nauta Ⅱand Ⅲ in 3 cases, Nauta Ⅱ, Ⅲ, and Ⅳ in 1 and both Nauta Ⅲ and Ⅳ in 1, respectively. Conclusion The cystic meningiomas have characteristic imaging features. CT and MRI, especially MRI, are valuable in the diagnosis.
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Objective To assess the clinical history and MRI findings of pituitary adenoma of different hormonesecreting type.Methods We retrospectively studied 200 postoperated patients,from 1996 to 2000,who all had the preoperated MRI exams.All cases had histopathological evalutions.Both clinical presentation(age,sex,symtom,sign)and MRI findings(size,form,signal intensity,extension)were investigated.Results There was a great span of age with sixty percent owing for 35~55 years old.The male and female proportion was 1∶2 in PRL hormone-secreting pituitary adenoma.12 cases with luleinizing hormone-secreting and 2 cases with thyrotropin hormone-secreting pituitary adenoma were just male.In other types the incidences were similar in man and woman.Clinical symptom and sign present overlapping.The volume of tumor was from 0.5 cm?0.8 cm?1 cm to 6 cm?7 cm?8 cm with most multihormone adenoma's maxium dimension out of 5 cm.The signal intensity was not characteristic pre-and post-enhancement.No calcification could be seen.In term of extension,most was to suprasellar,then infrasellar,unilateral or bilateral sinus cavernous,last was to lower part of the third ventricle.Conclusion Different hormonesecreting pituitary adenomas have some speciality in clinical and MRI presentation.Although an accurate diagnosis can not be made according to it,more information have been obtained.
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Objective To obtain magnetic resonance imaging(MRI) symptoms that could be used in medical diagnosis and identification by analyzing the diverse MRI appearance of brain multiple sclerosis(MS).Methods MRI findings of 41 samples of clinically definite MS, including the numbers, distributions, sizes, and shapes of the lesions were analyzed. The symbolic characteristics and enhanced expression are also covered.Results Brain MS might happen singly and multiply, and more frequently with multiple happening. In a multiple case, 4—15 lesions were observed the most. Some samples showed with diffuse lesions which were unable to be counted accurately presenting as a “dirty-appearing white matter”. The distribution of the lesions was observed most frequently at the two sides of periventricle, and following by the subcortical, corpus callosum, and brainstem. Only two lesions were observed at cerebrum. The size of most lesions range from a few millimeters to 2 cm, accounting for about 75% of the total samples. Lesions with size above 2 cm were seen seldomly, with the biggest one of 6—7 cm. According to the shapes and symptoms, lesions might be categorized as an acute and chronic ones. The acute lesions had a shape of oval or circle, with a swelling appearance, low signal of T_1WI, and isointensity or a slightly higher signal on the circle. T_2WI showed a high signal, with different increase and showing “core+lunar” sign. This kind of lesions showed an enhancement with the circle enhancement as the most typical one, which had a complete circle or non-conplete arc shape enhancement, even the big lesions. The chronic lesion might also be divided into two categories. One was the quasi-symmetric lesion, with the distribution along two sides of periventricle and with the shape of small puncture/patch, part of them merged into the big patch; another kind of lesions was found scattered sparsely at frontal, parietal lobes and two sides of the periventricle, with small patches in shape. The chronic lesions had an appearance of shrinking, sharp edge, even signals, and had no lunar circle phenomena and obvious enhancement.Conclusion Brain MS have diverse MRI appearence, with some of which are unique and symbolic.
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Objective To study the different patterns of hippocampal atrophy by MRI segmental analysis and to investigate the etiology and pathogenesis of temporal lobe epilepsy Methods GE 1 5 T Signa Horizon LX MRI scanner was used Oblique coronal T 1 weighted images perpendicular to the long axis of the hippocampus were obtained The mesial temporal structures were divided into four parts: the amygdala, hippocampal head, body and tail MRI patterns of atrophy in 50 patients with histologically confirmed hippocampal sclerosis were investigated by MRI volumetric measurement and segmental analysis, and the differences of clinical features and surgical outcome in different groups were compared Results Diffuse hippocampal atrophy was found in 22 of 50 patients (44%), 5 of the 50 patients (10%) showed diffuse atrophy involving both the amygdala and hippocampus 20 of the 50 patients (40%) had hippocampal focal atrophy and 8 of 50 patients (16%) had no obvious atrophy 38 of 50 (76%) hippocampal sclerosis had atrophy in the hippocampal body, 29 of 50 (58%) had hippocampal head atrophy, 24 of 50 (48%) had hippocampal tail atrophy, and the least involved part was the amygdala (16%, 8/50) 10 patients who had normal hippocampal volume showed focal hippocampal atrophy by segmental analysis Various patterns of hippocampal atrophy were found to be statistically related to the duration of epilepsy, the frequency of seizure and the outcome of surgery, respectively ( P 0 05) Conclusion MRI segmental analysis can improve the diagnostic sensitivity of temporal lobe epilepsy and help to investigate its etiology and pathogenesis
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Objective To explore the MRI and pathologic characteristics of hippocampal sclerosis. Methods 16 patients with hippocampal sclerosis were examined with transvers and oblique coronal T 1 weighted,T 2 weighted and fluid attenuated inversion recovery(FLAIR) MR imaging. Results Of 16 patients,1 case had bilateral hippocampal sclerosis;15 cases were ipsilateral(left n =9,right n =6) proved by pathology.The MR features of hippocampal sclerosis were as follows:hippocampal atrophy present in all patients;hyperintensity on coronal FLAIR in all patients and on coronal T 2W images present on 15 sides; loss of superficial sulci hippcampal head seen in 11 sides;disruption of the internal structures present on 13 sides; atrophy of lateral white matter present on 7 sides; enlargement of the ipsilateral temporal horn present on 6 sides;atrophy of the ipsilateral temporal lobe seen on 2 sides. Conclusion Atrophy and hyperintensity on coronal FLAIR and T 2 weighted images were the most common features of hippocampal sclerosis and had positive diagnostic value. Combination of coronal FLAIR and T 2 weighted imaging could improve the diagnostic sensitivity and accuracy for hippocampal sclerosis.
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0.05). Four lesions were only revealed on CE FLAIR whereas 7 lesions were only found on postcontrast T_1WI. Enhancing lesions located in cerebral hemisphere or the forth ventricle was revealed much more on T_1WI than that on CE FLAIR. However, postcontrast fast FLAIR images may be useful in detecting superficial abnormalities and those located in sulcus or lateral ventricle. The enhancement degree of enhanced T_1WI was much more intense than that of CE FLAIR(P0.05) and statistical significance in GWC, CNR and CER(P
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Objective To study the imaging features of the ventricular meningioma, in order to improve the understanding knowledge. Methods Compared with operative and pathological findings,the CT and MRI features of ventricular meningioma were analyzed in 22 patients (8 males and 14 females,range from 17~72 years old with average age 45 years).21 cases were examined by MRI(17 with enhanced scan),11 cases by CT(4 with enhanced scan).Results The ventricular meningioma were mostly fibrous type. Mostly, the locations were in the trigone of the lateral ventricle with regular shape. On imaging, the most were parenchymatous with markedly enhancement. Calcification may be found, but cystic changes and hemorrhage were very rare.Conclusion The ventricular meningiomas have characteristic imaging features. CT and MRI are valuable in diagnosis, especially MRI.